Embodiment
Battery provided by the invention has higher energy density, stable cycle performance, and as portable type electronic products such as mobile phone, notebook computers, electric automobile, the fields such as electric tool have considerable application prospect.
A kind of battery comprises positive pole 10, negative pole 20 and electrolyte (not shown).Anodal 10 comprise plus plate current-collecting body 12 and participate in the positive active material 14 of electrochemical reaction, and positive active material 14 can be reversible be deviate from-embedded ion; Negative pole 20 comprises negative current collector 22 at least; Electrolyte comprises at least a solvent that can dissolve electrolyte and make electrolyte ionization; Electrolyte can ionize out at least a charge and discharge process and reduce at negative pole-deposits and the active ion 28 of oxidation-dissolving.
See also shown in Figure 1ly, Fig. 1 is first embodiment of the invention battery structure schematic diagram, and in the first embodiment, battery cathode 20 only comprises negative current collector 22.
Positive active material 14 participates in anodal reaction, and can be reversible deviates from-embedded ion or functional group.Concrete, lithium ion, sodium ion, zinc ion or magnesium ion can reversiblely be deviate from-embed to positive active material 14.
Positive active material 14 can be to meet general formula Li
1+xMn
yM
zO
kCan the reversible compound of deviating from-embed the spinel structure of lithium ion, wherein ,-1≤x≤0.5,1≤y≤2.5,0≤z≤0.5,3≤k≤6, M is selected from least a in Na, Li, Co, Mg, Ti, Cr, V, Zn, Zr, Si, Al.Preferably, positive active material 14 contains LiMn
2O
4Preferred, positive active material 14 contains the LiMn through overdoping or coating modification
2O
4
Positive active material 14 can be to meet general formula Li
1+xM
yM′
zM″
cO
2+nCan the reversible compound of deviating from-embed the layer structure of lithium ion, wherein ,-1<x≤0.5,0≤y≤1,0≤z≤1,0≤c≤1 ,-0.2≤n≤0.2, M, M ', M " be selected from respectively Ni, Mn, Co, Mg, Ti, Cr, V, Zn, Zr, Si or Al at least a.Preferably, positive active material 14 contains LiCoO
2
Positive active material 14 can be to meet general formula Li
xM
1-yM′
y(XO
4)
nCan the reversible compound of deviating from-embed the olivine structural of lithium ion, wherein, 0<x≤2,0≤y≤0.6,1≤n≤1.5, M is selected from Fe, Mn, V or Co, M ' be selected from Mg, Ti, Cr, V or Al at least a, X is selected from least a in S, P or Si.Preferably, positive active material 14 contains LiFePO
4
In present Lithium Battery Industry, nearly all positive active material 14 all can be through modifications such as overdoping, coatings.But doping, it is complicated that the means such as coating modification cause the chemical general formula of material to express, as LiMn
2O
4Can not represent the general formula of now widely used " LiMn2O4 ", and should be with general formula Li
1+xMn
yM
zO
kBe as the criterion, comprise widely the LiMn through various modifications
2O
4Same, LiFePO
4And LiCoO
2Also should be interpreted as widely to comprise through modifications such as various doping, coatings, general formula meets respectively Li
xM
1-yM′
y(XO
4)
nAnd Li
1+xM
yM′
zM " cO
2+nPositive active material.
Positive active material of the present invention 14, can be selected as LiMn when deviating from-embedding the lithium ion compound for reversible
2O
4, LiFePO
4, LiCoO
2, LiM
xPO
4, LiM
xSiO
yCompounds such as (wherein M are a kind of variable valency metal).In addition, can deviate from-embed compound such as the NaVPO of sodium ion
4F can deviate from-embed compound such as the γ-MnO of zinc ion
2, can deviate from-embed compound such as the MgM of magnesium ion
xO
y(wherein M is a kind of metal, 0.5<x<3,2<y<6) and have similar functions, can deviate from-compound of embedded ion or functional group can be as the positive active material 14 of battery of the present invention.
In concrete execution mode, when the preparation anode sizing agent, except positive active material 14, also need add conductive agent and binding agent in anode sizing agent.
Conductive agent is selected from one or more in conducting polymer, activated carbon, Graphene, carbon black, carbon fiber, metallic fiber, metal dust and sheet metal.
Binding agent is selected from polyethylene oxide, polypropylene oxide, mixture and the derivative of a kind of or above-mentioned polymer in polyacrylonitrile, polyimides, polyester, polyethers, fluorinated polymer, poly-divinyl polyethylene glycol, polyethyleneglycol diacrylate, polyethylene glycol dimethacrylate.In embodiment, binding agent is selected from polytetrafluoroethylene (PTFE) or Kynoar (PVDF).
Plus plate current-collecting body 12 is only as the carrier of electrical conductivity and collection, do not participate in electrochemical reaction, namely in battery operated voltage range, plus plate current-collecting body 12 can be stable is present in electrolyte and does not have other side reactions to occur, thereby guarantees that battery has stable cycle performance.The material of plus plate current-collecting body 12 is selected from a kind of in carbon-based material, metal or alloy.
Concrete, carbon-based material is selected from vitreous carbon, graphite, carbon felt, carbon fiber or has a kind of in the electric conducting material of 3D bicontinuous structure.Wherein, the electric conducting material that has a 3D bicontinuous structure includes but are not limited to foamy carbon.Graphite includes but are not limited to graphite foil and graphite cake.
Metal is selected from Al, Fe, Cu, Pb, Ti, Cr, Mo, Co, Ag or a kind of through in the above-mentioned metal of Passivation Treatment.
Alloy is selected from stainless steel, aluminium alloy, Ni alloy, Ti alloy, Cu alloy, Co alloy, Ti-Pt alloy, Pt-Rh alloy or a kind of through in the above-mentioned alloy of Passivation Treatment.Stainless steel comprises stainless steel foil or stainless (steel) wire, and is concrete, and stainless model can be but be not limited to the stainless steel of 300 series, as stainless steel 304,316,316L or 316P.The model of aluminium alloy can be but be not limited to the aluminium alloy of 6000 series, as aluminium alloy 6061.
Negative pole 20 only comprises negative current collector 22, and negative current collector 22 does not participate in electrochemical reaction only as the carrier of electrical conductivity and collection.
The material of negative current collector 22 is selected from metal Ni, Cu, Ag, Pb, Mn, Sn, Fe, Al, Zn or at least a through in the above-mentioned metal of Passivation Treatment, perhaps elemental silicon, perhaps carbon-based material, wherein, carbon-based material comprises graphite material, such as the paper tinsel of business-like graphite compacting, wherein the shared part by weight scope of graphite is 90-100%.The material of negative current collector 22 can also be selected from stainless steel or through the stainless steel of Passivation Treatment.Stainless steel includes but are not limited to stainless (steel) wire and stainless steel foil, and is same, and stainless model can be but be not limited to the stainless steel of 300 series, as stainless steel 304,316,316L or 316P.
In addition, negative current collector 22 can also be selected from the metal that contains the high plating/coating of hydrogen-evolution overpotential, thereby reduces the generation of negative pole side reaction.Plating/coating is selected from the simple substance that contains C, Sn, In, Ag, Pb, Co, Zn, and alloy is perhaps at least a in oxide.The thickness range of plating/coating is 1-1000nm.For example: tin on the negative current collector plated surface of Copper Foil or graphite foil, plumbous or silver-colored.
The main purpose that plus plate current-collecting body 12 or negative current collector 22 are carried out Passivation Treatment is to make the surface of collector form the oxide-film of one deck passivation, thereby in battery charge and discharge process, can play stable collection and the effect of conduction electron, and can not participate in cell reaction, guarantee that battery performance is stable.The collector deactivating process for the treatment of comprises chemical passivation processing or electrochemical passivation processing.
Chemical passivation is processed and is comprised by oxidant oxidation collector, makes collection liquid surface form passivating film.The principle that oxidant is selected is that oxidant can make collection liquid surface form one deck passivating film and can not dissolve collector.Oxidant is selected from but is not limited only to red fuming nitric acid (RFNA) or ceric sulfate (Ce (SO
4)
2).
Concrete, the chemical passivation treatment step is: collector is inserted in oxidizing agent solution, kept 0.5-1 hour, make collection liquid surface form passivating film, take out at last collector and clean also dry.
In an embodiment with chemical passivation processing stainless (steel) wire or stainless steel foil, concrete Passivation Treatment process is: under 50 ℃, stainless steel is inserted 20% concentrated nitric acid solution, kept 0.5 hour, make stainless steel surfaces form passivating film, take out at last stainless steel water cleaning and dry in the drying box of 50 ℃.
In another processed the embodiment of stainless (steel) wire or stainless steel foil with chemical passivation, concrete Passivation Treatment process was: the Ce (SO that stainless steel is inserted 0.75mol/L
4)
2In solution, kept 0.5 hour, make stainless steel surfaces form passivating film, take out at last stainless steel water cleaning and dry in the drying box of 50 ℃.
Electrochemical passivation is processed and to be comprised collector is discharged and recharged or the battery that contains collector is discharged and recharged processing, makes collection liquid surface form passivating film.
Directly collector is discharged and recharged, namely is used for the battery assembling pre-Passivation Treatment of row of advancing at collector, concrete, to discharging and recharging with the three-electrode system of collector as work electrode, more corresponding selection suitable to electrode and reference electrode.During charging, voltage all is charged to 2.35-2.45V, and during discharge, voltage is all put to 1.35-1.45V.Collector can be metal, as metallic aluminium; Collector can be also alloy, as stainless steel or aluminium alloy.Certainly, also can adopt two electrode systems take collector as work electrode to discharge and recharge, during charging, voltage all is charged to 2.35-2.45V, and during discharge, voltage is all put to 1.35-1.45V.
In the execution mode of a direct passivation aluminium alloy collector, with aluminium alloy as work electrode, the conduct of zinc paper tinsel is to electrode and reference electrode, electrolyte is the aqueous solution that contains 1.5mol/L zinc acetate and 3mol/L lithium acetate, three-electrode system is discharged and recharged, during charging, voltage is charged to 2.4V, makes aluminum alloy surface oxidation under 2.4V form the oxide-film of one deck passivation, and during discharge, cut-ff voltage is 1.4V.
Reach the purpose of collector being carried out passivation thereby also can discharge and recharge the battery that contains collector, during charging, voltage all is charged to 2.35-2.45V, and during discharge, voltage is all put to 1.35-1.45V, discharges and recharges number of times and is not less than 1.Collector can be metal, as metallic aluminium; Collector can be also alloy, as stainless steel or aluminium alloy.
In carrying out the execution mode of Passivation Treatment after at one, collector being assembled into battery, positive active material 14 is LiMn
2O
4, plus plate current-collecting body 12 is aluminium alloy, negative current collector 22 is Copper Foil, electrolyte is the aqueous solution that contains 1.5mol/L zinc acetate and 3mol/L lithium acetate, during charging, voltage all is charged to 2.4V, and the cut-ff voltage when namely charging is 2.4V, makes aluminum alloy surface oxidation under 2.4V form one deck passivating film; During discharge, cut-ff voltage is 1.4V, battery is discharged and recharged number of times be not less than 1 time.The number of times of battery charging and discharging is more, and the effect of aluminium alloy passivation is better, and is more stable in electrolyte.
Adopting during electrochemical passivation processes the method for aluminium alloy, after during charging, voltage reaches 2.4V and keep a period of time, the corrosion current of aluminium alloy can significantly reduce along with the increase of holding time.Concrete, charging voltage reaches to hold time after 2.4V and progressively extended to 1 hour from 10 minutes, the corrosion current of aluminium alloy can significantly descend, hold time and progressively extended to 24 hours from 1 hour, it is not clearly that corrosion current descends, therefore, preferred, after charging voltage reaches 2.4V and kept at least 1 hour.
Electrolyte is weak acid or neutral aqueous solution, as chlorate, sulfate, nitrate, acetate, formates or phosphate, plus plate current-collecting body 12 and negative current collector 22 can keep stable in electrolyte, namely do not have side reaction to occur under battery operated voltage window, thereby guarantee the stability of battery performance.The deactivating process for the treatment of of collector provided by the invention all is suitable for plus plate current-collecting body 12 and negative current collector 22.
In order to make more even at negative pole 20 surface depositions of active ion 28 in electrolyte, negative pole 20 surfaces are formed with porous layer 30, and porous layer 30 is formed at negative pole 20 surfaces in any suitable mode as modes such as coating, compactings.
The thickness range of porous layer 30 is 0.05-1mm, and porous layer 30 has micron or sub-micron or nanoscale hole, and the volume range that micron or submicron order hole account for porous layer 30 is 50-95%.The nanoscale hole accounts for the 10-99% of porous layer 30 volume ranges, and the scope of the average diameter of nanoscale hole is 1-999nm, and preferred, the scope of the average diameter of nanoscale hole is 1-150nm.
Porous layer 30 does not participate in the electrochemical reaction of negative pole 20, porous layer 30 has very large specific area, larger deposition rate surface area can be provided for the active ion 28 that deposits in charging process-reduce, make active ion 28 more even on negative current collector 22 surface deposition ground, effectively reduce the generation of negative pole dendrite.In addition, by being formed at the porous layer 30 on negative current collector 22 surfaces, can also shorten migration distance in active ion 28 charge and discharge process, 28 of active ions need the shorter distance of diffusion just can complete charge and discharge process, have solved the problem that has diffusional resistance in active ion 28 courses of reaction.Simultaneously, owing to being provided with porous layer 30 at negative pole 20, can use thinner barrier film when the preparation battery, make in battery charging process, the oxygen that when especially overcharging, positive pole produces can more easily move to negative pole 20 and reduce, and strengthens the invertibity of battery.
The material of porous layer 30 is selected from carbon-based material, and carbon-based material is selected from least a in carbon black, activated carbon, carbon nano-tube, carbon fiber, graphite.
Carbon black includes but are not limited to section's qin carbon black (KB), acetylene black.KB has very large specific area and very strong adsorption capacity, can make active ion deposit ground on negative pole 20 more even, and the chemical property of the very strong conductive capability of KB can improve the high current charge-discharge of whole battery the time.
Carbon-based material can be the mixture of activated carbon and binding agent, and the weight range that activated carbon accounts for porous layer 30 is 20-99%.The specific area scope of activated carbon is 200-3000m
2/ g.Concrete, with commercialization activated carbon powder (particle size range 1-200mm) and evenly mixing of Kynoar (PVDF), add 1-METHYLPYRROLIDONE (NMP) to be dissolved into pasty state, be coated on negative current collector 22 surfaces.Porous layer 30 thickness ranges are 0.1-0.2mm, and the weight range that NMP accounts for the porous layer mixture is 50-70%.
The form of activated carbon includes but are not limited to activated carbon powder, active carbon particle, activated carbon-fiber felt or activated carbon fiber cloth, and the specific area scope of activated carbon-fiber felt or activated carbon fiber cloth is 100-2200m
2/ g.
Concrete, active carbon particle is mixed with electrically conductive graphite, then with PVDF, NMP evenly mixes, and is coated in negative current collector 22 surfaces.The thickness of porous layer 30 is between 0.1-0.2mm.The effect of electrically conductive graphite is to increase the electronic conduction ability of negative pole porous layer 30.Wherein, the weight range that activated carbon accounts for porous layer 30 is 20-80%, and the weight range that electrically conductive graphite accounts for porous layer 30 is 5-20%, and the weight range that bonding agent PVDF accounts for porous layer 30 is 5-15%.Active carbon material has loose structure and larger specific area, and also the carbon-based material of carbon nano-tube class is cheap relatively for price.And the technique of specifically making the negative pole that contains porous layer is also relatively simple, easily industrialization.
Preferably, negative pole 20 surfaces are formed with graphene layer.Graphene has outstanding heat conductivility and mechanical property, and theoretical specific area is up to 2600m
2/ g, and at a high speed electron mobility under room temperature, therefore, the graphene layer that is formed at negative pole 20 surfaces can not only provide for the deposition of active ion 28 larger surface area, can also further improve simultaneously the sub-ability of conduction of negative pole 20, thereby improve the chemical property of the large electric current of battery.
In the first embodiment, because negative pole 20 only comprises negative current collector 22, therefore, porous layer or graphene layer are to be formed at negative current collector 22 surfaces.
Electrolyte comprises at least a solvent that can dissolve electrolyte and make electrolyte ionization, and solvent comprises at least a in the aqueous solution or alcoholic solution, and alcoholic solution includes but are not limited to ethanol or methyl alcohol.
Electrolyte can ionize out at least a charge and discharge process at negative pole 20 and reduce-deposit and the active ion 28 of oxidation-dissolving.
The concentration range of active ion 28 is 0.5-15mol/L.In concrete execution mode, active ion 28 comprises metal ion, and metal is selected from least a in Zn, Fe, Cr, Cu, Mn, Ni, Sn.
Metal ion is present in electrolyte with forms such as chlorate, sulfate, nitrate, acetate, formates, phosphate.Preferably, metal ion is present in electrolyte with the form of the mixture of sulfate, acetate or sulfate and acetate.
Preferably, also comprise a kind of electrolyte in electrolyte, electrolyte can ionize out at least a charge and discharge process anodal 10 can the reversible ion of deviating from-embedding 16, thereby improves the ion-exchange speed in positive active material 14 and electrolyte, the high rate charge-discharge performance of raising battery.Concrete, positive active material 14 is for can the reversible compound of deviating from-embed lithium ion, and what electrolyte was corresponding can also ionize out lithium ion.The reversible ion of deviating from-embedding 16 comprises lithium ion or sodium ion or magnesium ion or zinc ion, and the concentration range of the reversible ion of deviating from-embedding 16 in electrolyte is 0.1-30mol/L.
In order to guarantee battery capacity, the concentration of the active ion 28 in electrolyte must reach certain limit, when electrolyte is crossed alkali, can affect the solubility of active ion 28 in electrolyte; When the electrolyte peracid, the problems such as proton embeds altogether in electrode material corrosion and charge and discharge process can appear, and therefore, in the present invention, the pH value scope of electrolyte is 3-7.
Please refer to shown in Figure 2ly, the charge-discharge principle of battery is: during charging, deviate from the reversible ion of deviating from-embedding 16 in positive active material 14, follow simultaneously the interior variable valency metal of positive active material 14 oxidized, and ejected electron; Electronics arrives battery cathode 20 via external circuit, and the active ion 28 in electrolyte obtains electronics at negative pole 20 and is reduced simultaneously, and is deposited on negative current collector 22 surfaces, forms active ion sedimentary deposit 26.Discharge process is the inverse process for charging, as shown in Figure 3.
In the first embodiment, working first of battery is to deviate from the reversible ion of deviating from-embedding 16, active ion 28 in positive active material 14 to reduce-be deposited as the charging process of active ion sedimentary deposit 26 at negative pole 20.The capacity of battery depends on the capacity of positive active material 14, therefore, during the battery initial charge, needs to comprise enough reversible ions of deviating from-embedding 16 in positive active material 14.User's battery before not carrying out charging process can not use as power supply, has therefore guaranteed that the capacity of battery is not subject to any type of loss before use.
The second execution mode
Please refer to shown in Figure 4, second embodiment of the invention provides a kind of battery, with the difference of the battery that discloses in the first execution mode be: in the second execution mode, negative pole 20 also comprises the negative electrode active material 24 that is formed at negative current collector 22 surfaces, negative electrode active material 24 can oxidation in discharge process-be dissolved as active ion 28.
Negative current collector 22 is only as the carrier of electrical conductivity and collection, do not participate in negative pole 20 reactions, and the method for negative electrode active material 24 by coating, plating or sputter is formed on negative current collector 22, and sputtering method includes but are not limited to magnetron sputtering.Concrete, negative current collector 22 is Copper Foil, and negative electrode active material 24 is zinc, and zinc is formed at copper foil surface by electric plating method.
Preferably, negative electrode active material 24 is formed on negative current collector 22 through surface preparation, and the method for surface preparation comprises at least a in mechanical treatment, chemical treatment or electrochemical treatments.Concrete, when negative current collector 22 is Cu, it can be manual/mechanical grinding that Cu is carried out pretreated method, remove the dim part in its surface and make simultaneously its surface have certain roughness, but because hand sand can not be removed the lip-deep impurity of Cu thoroughly, as CuO, therefore Cu is needed further chemical treatment, chemically treated method can be that the mixed liquor of the different acid of preparation soaks it, as sulfuric acid, and nitric acid and hydrochloric acid.Pretreated concrete grammar depends on the selection of negative current collector 22, normally machinery, chemistry, three kinds of method combinations of electrochemistry.
In present embodiment, negative pole 20 comprises negative current collector 22 and negative electrode active material 24, and therefore, porous layer or graphene layer are to be formed at negative current collector 22 surfaces.Negative electrode active material is formed at porous layer by modes such as coating, plating or sputters or graphene layer is surperficial.
Same, anodal 10 comprise plus plate current-collecting body 12 and positive active material 14.plus plate current-collecting body 12 does not participate in electrochemical reaction, positive active material 14 can be reversible be deviate from-embedded ion, as lithium ion, sodium ion, zinc ion or magnesium ion, but in the second execution mode, need not limit positive active material 14 and itself whether contain lithium ion when the preparation battery, sodium ion, zinc ion or magnesium ion, specifically, positive active material 14 can have four kinds of states: do not contain the reversible ion of deviating from-embedding 16, contain and can further embed the reversible ion of deviating from-embedding 16, contain the reversible ion of deviating from-embedding 16 and the reversible ion of deviating from-embedding 16 state that reaches capacity, contain the reversible ion of deviating from-embedding 16 and the reversible ion of deviating from-embedding 16 reaches hypersaturated state.
Electrolyte comprises at least a solvent that can dissolve electrolyte and make electrolyte ionization, and solvent comprises the aqueous solution or alcoholic solution, and alcoholic solution includes but are not limited to ethanol and methyl alcohol.
At this moment, electrolyte can ionize out at least a charge and discharge process negative pole 20 reduce-deposit and the active ion 28 of oxidation-dissolving or at least a charge and discharge process in can the reversible ion of deviating from-embedding 16 or contain simultaneously active ion 28 and the reversible ion of deviating from-embedding 16 anodal 10.
the battery that the second execution mode discloses, positive active material 14 can be reversible in charge and discharge process be deviate from-embedded ion, but for positive active material 14 itself, can not comprise the reversible ion of deviating from-embedding 16, can comprise the hole of accepting the reversible ion of deviating from-embedding 16 can also be arranged in the reversible ion of deviating from-embedding 16 and internal structure, can also be self to comprise the reversible ion of deviating from-embedding 16 and the even hypersaturated state of state that reaches capacity, therefore, the positive active material 14 of battery has very large selection space in selection, further, can comprise active ion 28 and/or the reversible ion of deviating from-embedding 16 in electrolyte, make the battery in the present invention to select different battery operated patterns according to different application scenarios, the battery strong adaptability.Below further set forth the mode of operation of positive active material 14 and the battery that electrolyte consists of of different conditions.
A kind of battery comprises positive pole 10, negative pole 20, electrolyte (not shown).Anodal 10 comprise plus plate current-collecting body 12 and positive active material 14, and positive active material 14 can be reversible be deviate from-embedded ion.Negative pole 20 comprises negative current collector 22 and participates in the negative electrode active material 24 of electrochemical reaction.Electrolyte comprises at least a solvent that can dissolve electrolyte and make electrolyte ionization.Electrolyte can ionize out and at least aly anodal 10, the reversible ion of deviating from-embedding 16 can occur; Positive active material 14 does not contain the reversible ion of deviating from-embedding 16; Working first of battery is that in electrolyte, the reversible ion of deviating from-embedding 16 is embedded into positive active material 14, negative electrode active material 24 oxidations-the be dissolved as discharge process of active ion 28.
Concrete, positive active material 14 is Mn
2O
4, negative electrode active material 24 is Metal Zn, comprises LiAc in electrolyte.Owing to not containing lithium in positive active material 14, and comprise lithium ion in electrolyte, therefore, battery is worked first as lithium ion in electrolyte is embedded into positive active material 14, negative electrode active material 24 Metal Zn oxidations-be dissolved as Zn
2+Discharge process.
Preferably, also comprise the electrolyte that can ionize out active ion 28 in electrolyte, active ion 28 can reduce-deposit and oxidation-dissolving at negative pole 20, like this, when battery discharge, can accelerate negative pole 20 and electrolyte intermediate ion exchange velocity.
If positive active material 14 meets in charge and discharge process and can be reversible to deviate from-this condition of embedded ion gets final product work, must contain the reversible ion of deviating from-embedding 16 and need not limit positive active material 14.Although positive active material 14 does not comprise can the reversible ion of deviating from-embedding 16, battery is required to be discharge process when working first, but during the battery of user in buying the present invention, can directly use as power supply equally, battery is very long simultaneously.
A kind of battery comprises positive pole 10, negative pole 20, electrolyte.Anodal 10 comprise plus plate current-collecting body 12 and positive active material 14, negative pole 20 comprises negative current collector 22 and participates in the negative electrode active material 24 of electrochemical reaction, electrolyte comprises at least a solvent that can dissolve electrolyte and make electrolyte ionization, and electrolyte can ionize out and at least aly reduce-deposit and the active ion 28 of oxidation-dissolving and at least aly at positive pole 10, the reversible ion of deviating from-embedding 16 can occur at negative pole 20; The reversible ion of deviating from-embedding 16 can be deviate from and embed to positive active material 14; Working first of battery is that the reversible ion of deviating from-embedding 16 is deviate from from positive active material 14, active ion 28 reduces and charging process or 16 embedding positive active material 14, negative electrode active material 24 oxidations of the reversible ion of deviating from-embedding that deposit and the discharge process that is dissolved as active ion 28 at negative pole 20.
Concrete, positive active material 14 contains Li
1-xMn
2O
4, negative electrode active material 24 is Metal Zn, comprises zinc acetate and lithium acetate in electrolyte.Positive active material 14 can be deviate from Li
+, simultaneously, but also have Li in the electrolysis liquid of hole in the spinel structure of positive active material 14
+Embed, therefore, battery mode of operation first can be discharge: the Li in electrolyte
+Be embedded into Li
1-xMn
2O
4, negative electrode active material 24 Metal Zn oxidations also are dissolved as Zn
2+Battery mode of operation first can be charging: i.e. Li
1-xMn
2O
4In deviate from Li
+, the Zn in electrolyte
2+Reduce and deposit at negative pole 20 and form active ion sedimentary deposit 26.
Therefore, it can be both charging process that battery is worked first, can be also discharge process.During the battery of user in buying the present invention, be that battery is charged or battery is discharged before need not to consider to use, can use, and battery of the present invention be very long.
Preferably, battery is worked first and is deviate from from positive active material 14 for the reversible ion of deviating from-embedding 16, the charging process that active ion 28 reduces-deposits at negative pole 20.
A kind of battery comprises positive pole 10, negative pole 20, electrolyte, and anodal 10 comprise plus plate current-collecting body 12 and positive active material 14, and negative pole 20 comprises negative current collector 22 and participates in the negative electrode active material 24 of electrochemical reaction; Electrolyte comprises at least a solvent that can dissolve electrolyte and make electrolyte ionization; Electrolyte can ionize out and at least aly anodal 10, the reversible ion of deviating from-embedding 16 can occur; The reversible ion of deviating from-embedding 16 can be deviate from and embed to positive active material 14; Working first of battery is that the reversible ion of deviating from-embedding 16 embeds positive active materials 14, negative electrode active material 24 oxidations-the be dissolved as discharge process of active ion 28.
Concrete, positive active material 14 contains Li
1-xMn
2O
4, negative electrode active material 24 is Metal Zn, comprises lithium acetate in electrolyte.Positive active material 14 can be deviate from Li
+, also can embed Li
+, contain Li in electrolyte
+, therefore, it is Li that battery is worked first
+Be embedded into Li
1-xMn
2O
4, Metal Zn oxidation-be dissolved as Zn
2+Discharge process.
Although working first, battery is required to be discharge process, but during the battery of user in buying the present invention, can directly use as power supply equally, and not affect the performance of battery, and can discharge and recharge normally after battery is worked first, battery is very long simultaneously.
A kind of battery comprises anodal 10, negative pole 20, electrolyte, and anodal 10 comprise plus plate current-collecting body 12 and positive active material 14, and positive active material 14 can be reversible be deviate from-embedded ion; Negative pole 20 comprises negative current collector 22 and participates in the negative electrode active material 24 of electrochemical reaction; Electrolyte comprises at least a solvent that can dissolve electrolyte and make electrolyte ionization; Electrolyte can ionize out and at least aly reduce-deposit and the active ion 28 of oxidation-dissolving at negative pole 20; Battery work first be reversiblely deviate from-embedded ion from positive active material 14 deviate from, active ion 28 is in the charging process of negative pole 20 reduction-deposition.
Concrete, positive active material 14 contains Li
1-xMn
2O
4, negative electrode active material 24 is Metal Zn, contains zinc acetate in electrolyte, positive active material 14 can be deviate from Li
+, also can embed Li
+, therefore, it is Li that battery is worked first
+From Li
1-xMn
2O
4In deviate from, the Zn in electrolyte
2+The charging process of reducing-depositing at negative pole 20.
A kind of battery comprises anodal 10, negative pole 20, electrolyte, and anodal 10 comprise plus plate current-collecting body 12 and positive active material 14, and positive active material 14 can be reversible be deviate from-embedded ion; Negative pole 20 comprises negative current collector 22 and participates in the negative electrode active material 24 of electrochemical reaction; Electrolyte comprises at least a solvent that can dissolve electrolyte and make electrolyte ionization; Electrolyte can ionize out at least a active ion 28 that reduces-deposit at negative pole 20; The reversible ion of deviating from-embedding 16 state that reaches capacity in positive active material 14; Battery work first be the reversible ion of deviating from-embedding 16 from anodal 10 deviate from, active ion 28 is in the charging process of negative pole 20 reduction-deposition.
As well known to those skilled in the art, in positive active material 14, the reversible ion of deviating from-embedding 16 is in saturation condition, be that the reversible ion of deviating from-embedding 16 occupies the VOID POSITIONS in positive active material 14 structures substantially, and positive active material 14 Stability Analysis of Structures can steady operation in battery charge and discharge process.
Battery is worked first and is required to be charging process, and namely the reversible ion of deviating from-embedding 16 is deviate from from positive active material 14, and the active ion 28 in electrolyte reduces-deposits at negative pole 20.Although the user needs it is carried out charging operations when buying this battery, just because of this, battery capacity can not be subject to any type of loss before using first, thereby has guaranteed the performance that battery used in the later stage.
Preferably, also comprise in electrolyte ionizing out the electrolyte that the reversible ion of deviating from-embedding 16 can occur at positive pole 10, like this, when battery discharge, can accelerate the exchange velocity of positive pole 10 and electrolyte intermediate ion, improve battery high rate charge-discharge performance.
Therefore, can reduce-deposit and the active ion 28 of oxidation-dissolving can be able to allow battery operated at negative pole 20 as long as electrolyte comprises, that is to say, in the electrolyte of this battery, only need to add active ion 28, and not mandatory requirement need to contain can the reversible ion of deviating from-embedding 16, can make the battery normal operation.The bath composition of battery is simple, low cost of manufacture, and battery has widely to be used.
A kind of battery comprises anodal 10, negative pole 20, electrolyte, and anodal 10 comprise plus plate current-collecting body 12 and positive active material 14, and positive active material 14 can be reversible be deviate from-embedded ion; Negative pole 20 comprises negative current collector 22 and participates in the negative electrode active material 24 of electrochemical reaction; Electrolyte comprises at least a solvent that can dissolve electrolyte and make electrolyte ionization; Electrolyte can ionize out at least a active ion 28 that reduces-deposit at negative pole 20; In positive active material 14, the reversible ion of deviating from-embedding 16 is in hypersaturated state; Battery work first be the reversible ion of deviating from-embedding 16 from anodal 10 deviate from, active ion 28 reduces-is deposited as the charging process of negative electrode active material 24 at negative pole 20.
As well known to those skilled in the art, in positive active material 14, the reversible ion of deviating from-embedding 16 is in hypersaturated state, when namely preparing positive active material 14, be on saturated basis at positive active material 14, further positive active material 14 is carried out the embedding ion processing, to improve the capacity of positive active material 14, in order to guarantee the Stability Analysis of Structures of positive active material 14, the surface of positive active material 14 is modified or is coated by metal or metal oxide.Concrete, metal includes but are not limited to Al, and metal oxide includes but are not limited to Al
2O
3
Concrete, positive active material 14 is Al
2O
3The Li that coats
1+xMn
2O
4(0<x<0.5), negative electrode active material 24 is Metal Zn, comprises zinc acetate in electrolyte.In positive active material 14, the content of Li+ has reached hypersaturated state, and therefore, it is Li that battery is worked first
+From Li
1+xMn
2O
4In deviate from, the Zn in electrolyte
2+Reduce-be deposited as the charging process of active ion sedimentary deposit 26 at negative pole 20.
Preferably, also comprise in electrolyte ionizing out the electrolyte that the reversible ion of deviating from-embedding 16 can occur at positive pole 10, like this, when battery charges, can accelerate positive pole 10 and electrolyte intermediate ion exchange velocity, improve the battery charging and discharging performance.
The negative electrode active material 24 that comprises negative current collector 22 and participation electrochemical reaction due to the negative pole 20 of battery in the second execution mode, so the mode of operation first of battery has had more selection, thus, the producer can be according to user's application scenario, select the collocation of positive pole 10, negative pole 20 and electrolyte in battery, produce the battery with different charge and discharge modes.
The 3rd execution mode
Third embodiment of the invention has also disclosed a kind of battery, the difference of the battery that discloses with the second execution mode is: in the 3rd execution mode, negative pole 20 only comprises negative current collector 22, but negative current collector 22 is not only as the carrier of electrical conductivity and collection, also be equivalent to simultaneously negative electrode active material and can participate in negative pole 20 reactions, can oxidation in battery discharge procedure-be dissolved as active ion 28, the material that is negative current collector 22 is identical with the simple substance material of active ion 28, for example: active ion 28 is zinc ion, and corresponding negative current collector 22 is metallic zinc.
In the 3rd execution mode, negative pole 20 comprises the negative current collector 22 that participates in electrochemical reaction, and therefore, porous layer or graphene layer are to be formed at negative current collector 22 surfaces.In the 3rd execution mode, the positive active material 14 of anode 10 is LiMn
2O
4, plus plate current-collecting body 12 is stainless (steel) wire, and negative current collector 22 is metallic zinc, and electrolyte is the aqueous solution that contains zinc salt.Preferably, electrolyte is the aqueous solution that contains zinc salt and lithium salts.Metallic zinc can participate in negative pole 20 reactions.
When the battery in the present invention such as need were used barrier film, barrier film can be the porous material of organic or inorganic, and the porosity ranges of barrier film is 20-95%, and pore diameter range is 0.001-100 μ m.
Battery provided by the invention, has energy density high (can reach the 60%-80% of lithium ion battery), power density (is expected to reach 200% of lithium ion battery greatly, even higher), be easy to make, totally nontoxic, environmental protection, easily reclaim and with low cost (battery of same capacity is expected to reach 60% of lead-acid battery, 20% of lithium ion battery, even lower) etc. characteristics, and have good cycle performance, in embodiment, battery capacity after 4000 weeks of circulation still maintains more than 90%.Therefore, the battery in the present invention is as the green energy resource of a new generation, is suitable as very much the energy storage system in large-scale energy storage field and the substitute of lead-acid battery.
Weight, the unit in percent by volume in the present invention are well-known to those skilled in the art, and for example percent by volume refers to the weight of solute in the solution of 100 milliliters.Unless otherwise defined, all specialties of using in literary composition are identical with the meaning that scientific words and one skilled in the art are familiar with.In addition, any method similar or impartial to described content and material all can be applicable in the inventive method.The use that better implementation method described in literary composition and material only present a demonstration.
Below in conjunction with embodiment, be described more specifically content of the present invention.Should be appreciated that enforcement of the present invention is not limited to the following examples, any pro forma accommodation and/or change that the present invention is made all will fall into protection range of the present invention.In the present invention, if not refer in particular to, all part, percentages are unit of weight, and all equipment and raw material etc. all can be buied from market or the industry is commonly used.
By cyclic voltammetry (CV), build three-electrode system and test the stability of different collectors in electrolyte.
Embodiment 1-1
Take stainless steel as work electrode, the stainless steel model is 304, and zinc electrode is to electrode and reference electrode, at stannous sulphate electrolyte 2mol/L ZnSO
4With 2mol/L Li
2SO
4In study stainless electrochemical behavior by cyclic voltammetry, voltage range is 1.0-2.4V.Stainless steel does not pass through Passivation Treatment.
Fig. 5 is the cyclic voltammetry curve of the stainless steel 304 that in embodiment 1-1, unpassivated is processed.As can be seen from the figure stainless steel anode when scanning first, locate to occur a wide oxidation peak at 1.9V (Vs.Zn), obvious O then occurred
2Separate out the peak, be accompanied by electric current and increase.In the scanning of subsequently negative electrode, the reduction peak of less has appearred at the 1.4V place.The oxidation peak at the 1.9V place after 1 time of circulating is hindered, and means in circulating for the first time forming oxide layer at stainless steel surfaces, and oxide layer has suppressed the further oxidation of stainless steel surfaces internal layer.But perhaps oxide layer can cause O
2Separate out.Therefore cause separating out the peak to the low potential migration and becoming increasing of oxygen.
Embodiment 1-2
Take the stainless steel of passivation as work electrode, the stainless steel model is 316, and zinc electrode is to electrode and reference electrode, at stannous sulphate electrolyte 2mol/L ZnSO
4With 2mol/L Li
2SO
4In study the stainless electrochemical behavior of passivation by cyclic voltammetry, voltage range is 1.0-2.4V.
The stainless method of passivation is chemical passivation, and detailed process is: under 50 ℃, Stainless steel 316 is inserted 20% concentrated nitric acid solution, keep 0.5h, make stainless steel surfaces form passivating film, take out at last the stainless steel water and clean also dry.
Fig. 6 is the stainless cyclic voltammetry curve of process Passivation Treatment in embodiment 1-2.
Experimental result is presented at solution such as the dense HNO that contains oxidant
3In solution, after passivation, it is more stable that stainless steel becomes, and O
2Separate out the peak favorable reproducibility, at different cycle period O
2Separate out not significantly difference of peak shape.On the other hand, O
2Evolution or deposition potential moves to high potential a little, and does not occur separating out of obvious oxygen before 2.0V.This result is extremely important to the water system battery, because highly stable in the battery operated voltage range of water system through the stainless steel of transpassivation.
Embodiment 1-3
Take the stainless steel of passivation as work electrode, the stainless steel model is 316P, and zinc electrode is to electrode and reference electrode, at nitrate electrolyte 3mol/L Zn (NO
3)
2With 6mol/L LiNO
3In study the stainless electrochemical behavior of passivation by cyclic voltammetry, voltage range is 1.0-2.4V.
The stainless method of passivation is with embodiment 1-2.
Fig. 7 is the Stainless steel 316 P CV curve in nitrate electrolyte through Passivation Treatment.
Embodiment 1-4
Take aluminium alloy as work electrode, zinc electrode is to electrode and reference electrode, at acetate electrolyte 1.5mol/L Zn (Ac)
2With study the electrochemical behavior of aluminium alloy in 3mol/L LiAc by cyclic voltammetry, voltage range is 1.0-2.4V, aluminium alloy is in 2.4V lower surface generation passivation.
Embodiment 1-5
Take aluminium alloy as work electrode, zinc electrode is to electrode and reference electrode, at stannous sulphate electrolyte 2mol/L ZnSO
4With 2mol/L Li
2SO
4In study the electrochemical behavior of aluminium alloy by cyclic voltammetry, voltage range is 1.0-2.4V, aluminium alloy is in 2.4V lower surface generation passivation.
Fig. 8 and Fig. 9 are respectively the CV curve of aluminium alloy in acetate and stannous sulphate electrolyte in embodiment 1-4 and 1-5.In Fig. 8, during anode scanning first, significant oxidation peak has appearred, and fluctuation appears in electric current slightly, non-faradic currents or other processes that this phenomenon may produce owing to oxidation or the ionic adsorption of aluminum alloy surface.Aluminium alloy surface when 2.4V by electrochemical oxidation, forms passivating film, after anode scanning for the first time, at 1.0-2.1V all without any the peak, and O
2Evolution or deposition potential moves to high potential, analyses the oxygen electric current and diminishes.Show through the aluminium alloy after electrochemical passivation highly stable in the battery operated voltage range of water system.
Embodiment 1-6
Take graphite foil as work electrode, zinc electrode is to electrode and reference electrode, at hydrochloride electrolyte 4mol/L ZnCl
2With study the electrochemical behavior of graphite foil in 3mol/L LiCl by cyclic voltammetry.
Embodiment 1-7
The stainless steel of processing take unpassivated is as work electrode, and zinc electrode is to electrode and reference electrode, at hydrochloride electrolyte 4mol/L ZnCl
2With study by cyclic voltammetry the stainless electrochemical behavior that unpassivated is processed in 3mol/L LiCl.
Figure 10 and Figure 11 are respectively the CV curve of embodiment 1-6 and 1-7.Can find out that by the CV curve graphite foil is relatively stable in solution of chlorate, except the separating out of oxygen occurs under high potential, obvious oxidation or reduction peak do not appear under whole electrochemical window, this phenomenon has been proved carbon-based material and has been adapted in solution of chlorate as collector, and the stainless steel that unpassivated is processed not too is suitable for solution of chlorate.
By the Tafel curve, build three-electrode system and test the corrosion rate of different collectors in acetate electrolyte.
Embodiment 2-1
Take aluminium foil as work electrode, zinc is to electrode and reference electrode, at acetate electrolyte 1.5mol/LZn (Ac)
2In 3mol/L LiAc, study the corrosion behavior of aluminium foil by the Tafel curve.
Embodiment 2-2
As work electrode, its excess-three electrode composition and test condition are with embodiment 2-1 with the stainless steel 304 rod.
Embodiment 2-3
As work electrode, its excess-three electrode composition and test condition are with embodiment 2-1 with graphite rod.
Embodiment 2-4
As work electrode, its excess-three electrode composition and test condition are with embodiment 2-1 with aluminium alloy.
Embodiment 2-5
With the stainless steel 304 of passivation as work electrode, its excess-three electrode form and test condition with embodiment 2-1.Concrete stainless steel is processed by chemical passivation.
Embodiment 2-6
Take the aluminium alloy of passivation as work electrode, its excess-three electrode form and test condition with embodiment 2-1.Aluminium alloy is processed by electrochemical passivation, aluminium alloy is discharged and recharged charge and discharge cycles 1 time.
Embodiment 2-7
With the aluminium alloy of passivation as work electrode, its excess-three electrode form and test condition with embodiment 2-1.Concrete aluminium alloy is processed by electrochemical passivation, aluminium alloy is discharged and recharged electrochemical passivation charge and discharge cycles 50 times.
Corrosion current can obtain from Tafel curve and formula 1.Based on area, density and the possible corrosion mechanism (quantity of electron transfer in corrosion process) of work electrode, obtain the corrosion rate of several different plus plate current-collecting bodies as shown in table 1, wherein.R is corrosion resistance, I
CorrBe corrosion current.
Formula 1:
Table 1
As can be seen from Table 1: the corrosion rate of aluminium foil is the highest, and stainless steel and the aluminium alloy corrosion rate in acetate solution is little 10 times than aluminium foil.Respectively through the stainless steel after chemical passivation and electrochemical passivation processing and corrosion rate decline 6-12 times of aluminium alloy.And the corrosion rate after the further electrochemical oxidation of aluminium alloy also can further descend, and 50 post-etching speed of electrochemicial oxidation circulation descend 150 times.This result and CV result are coincide, and the CV result shows that analysing the oxygen curve after circulation for several times dies down.
Further, study the chemical property of battery by specific embodiment.
Embodiment 3-1
With LiMn
2O
4Be positive active material, positive active material, conductive agent acetylene black (AB), binding agent Kynoar (PVDF) mixed and are dissolved in 1-METHYLPYRROLIDONE (NMP) making anode sizing agent according to the part by weight of 83: 10: 7.Plus plate current-collecting body is graphite foil, and anode sizing agent evenly is coated on plus plate current-collecting body, and under 110 ℃, drying was made positive pole in 24 hours in air.The battery cathode collector is stainless steel.Electrolyte is to contain the aqueous solution that concentration is 4mol/L zinc chloride and 3mol/L lithium chloride, by titration 0.1mol/L lithium hydroxide in electrolyte, the pH value of electrolyte is adjusted to 4.Barrier film is the glass felt-cloth.Positive pole, negative pole are assembled into battery, and the centre separates with barrier film, injects electrolyte.Treat that battery pack began with 4C multiplying power charging and discharging after installing in standing 12 hours subsequently.The charging/discharging voltage interval is 1.4-2.15V.
The voltage of the battery that Figure 12 provides for embodiment of the present invention 3-1 and the relation curve of discharge capacity, the enclosed pasture efficient of battery is about 97%, and showing simultaneously in the good and cyclic process of the chemical property of battery does not almost have side reaction to occur yet.
The discharge capacity of the battery that Figure 13 provides for embodiment of the present invention 3-1 and the relation curve of cycle-index, as can be seen from the figure, the battery initial capacity is 0.35mAh, is 117mAhg based on the specific capacity of positive electrode
-1, and the volumetric efficiency of circulating battery after 1000 weeks still have 90%, shows that the cycle performance of battery is very good.
Embodiment 3-2
In embodiment 3-6, battery positive electrode active material is Li
1.08Co
0.03Al
0.03Mn
1.94O
4, all the other battery formations are identical with embodiment 3-1 with assemble method.
The discharge capacity of the battery that Figure 14 provides for embodiment 3-2 and the relation curve of cycle-index, as can be seen from the figure, the volumetric efficiency of circulating battery after 4000 weeks still has 95%, shows the LiMn that adopts doping vario-property to process
2O
4The cycle life of the battery of positive active material further obtains to improve.
Embodiment 3-3
With Li
1.05Mn
1.89Co
0.03Al
0.03O
4Be positive active material, positive active material, binding agent PVDF, super-p carbon black mixed and are dissolved in 1-METHYLPYRROLIDONE (NMP) making anode sizing agent according to the part by weight of 83: 10: 7, plus plate current-collecting body is the graphite cake of thickness 1mm.The charging/discharging voltage interval is 1.5-2.1V.All the other formations of battery and method of testing are with embodiment 3-1.
Figure 15 is the discharge capacity of the battery that provides of embodiment 3-3 and the relation curve of cycle-index, can clearly find out from figure, the discharge capacity that circulating battery is 4000 times is with discharge capacity is almost equal first, and battery not only cycle performance is highly stable, and has extended cycle life.
Figure 16 is the enclosed pasture efficient of the battery that provides of embodiment 3-3 and the relation curve of cycle-index, and as can be seen from the figure after circulating battery 4000 times, enclosed pasture efficient shows that still near 100% the charge-discharge performance of the battery in the present invention is highly stable.
Embodiment 3-4
With LiMn
2O
4Be positive active material, positive active material, polyfluortetraethylene of binding element (PTFE), super-p carbon black mixed and are dissolved in 1-METHYLPYRROLIDONE (NMP) making anode sizing agent according to the ratio of 83: 10: 7.Plus plate current-collecting body is the stainless (steel) wire of thickness 30 μ m, and stainless steel evenly is coated on anode sizing agent on plus plate current-collecting body without passivation, and under 110 ℃, drying was made positive pole in 24 hours in air.The battery cathode collector is thickness 10 μ m Copper Foils.Electrolyte is to contain the aqueous solution that concentration is 1mol/L lithium acetate and 1.5mol/L zinc acetate, by titration 0.1mol/L lithium hydroxide and 0.1mol/LHAc in electrolyte, the pH value of electrolyte is adjusted to 4.Barrier film is the glass felt-cloth.Positive pole, negative pole are assembled into battery, and the centre separates with barrier film, injects electrolyte.Treat that battery pack began with 0.5C multiplying power charging and discharging after installing in standing 12 hours subsequently.The charging/discharging voltage interval is 1.5-2.1V.
Figure 17 is the discharge capacity of the battery that provides of embodiment 3-4 and the relation curve of cycle-index.Can clearly see from figure: battery discharge capacity first is, the discharge capacity that circulates after 250 times does not almost have difference with discharge capacity first, shows that the cycle performance of battery is highly stable, and battery provided by the invention has excellent chemical property.
Embodiment 4-1
With LiMn
2O
4Be positive active material, ratio according to positive active material 90%, conductive carbon black 6%, bonding agent SBR (butadiene-styrene rubber breast) 2%, thickener CMC (sodium carboxymethylcellulose) 2%, first CMC is mixed with certain water gaging, add again positive active material and conductive carbon black, stirred 2 hours, and added at last SBR to stir and obtained anode sizing agent in 10 minutes.Plus plate current-collecting body is the graphite foil of thickness 0.1mm, anode sizing agent evenly is coated on plus plate current-collecting body, and thickness 0.3mm, positive plate was made in 120 degree oven dry in 12 hours.The battery cathode collector is the graphite foil of thickness 0.1mm.(coconut husk is fired, specific area 1500m with the activated carbon powder
2/ g), and conductive carbon black, PVDF mixes with the ratio of 90: 5: 5, adds NMP that it is dissolved, and evenly is coated on the negative current collector graphite foil and makes porous layer, and thickness is 0.1mm.Electrolyte is to contain the aqueous solution that concentration is 4mol/L zinc chloride and 3mol/L lithium chloride, and barrier film is the nonwoven fabrics barrier film.With positive plate, negative plate is assembled into battery, and the centre separates with barrier film.Inject electrolyte, the electrolyte major part is stored in porous layer, the Zn in charge and discharge process in electrolyte
2+/ Zn reduces at negative pole-deposits and oxidation-solubilizing reaction, especially reduces-deposits and oxidation-solubilizing reaction on the interface between porous layer inside and porous layer and negative current collector.Figure 18 is the structural representation that negative pole currect collecting of the present invention surface is formed with porous layer.In charge and discharge process, zinc is in negative pole deposition/dissolving.In activated carbon, micron-sized hole can effectively adsorb a large amount of electrolyte and zinc deposition basic point is provided.Figure 19 is the partial enlarged drawing of porous layer in Figure 18, can obviously see the active ion sedimentary deposit 26 that is deposited on porous layer inside.Treat that battery pack began with 1C multiplying power charging and discharging after installing in standing 12 hours subsequently.The charging/discharging voltage interval is 1.4-2.15V (namely with the electric current constant current charge of 100mAh to 2.15V, then constant-current discharge is to 1.4V, so cycling).Figure 20 is the LiMn of embodiment of the present invention 4-1
2O
4/ Zn battery first charge-discharge voltage-capacity curve figure.
Embodiment 4-2
The mode identical with embodiment 4-1 made battery, and different is zinc-plated as the battery cathode collector with Copper Foil.Relative graphite foil, the Copper Foil electric conductivity is better, and mechanical strength is higher, and is also thinner.Adopt Copper Foil to be conducive to improve the negative discharge performance of battery, also can reduce the battery volume simultaneously, improve the volume energy density of battery.But simple Copper Foil can not be as the negative pole of ion-exchange battery, because at copper foil surface, the efficient of zinc deposition is very low.Therefore, can plate one deck tin at copper foil surface, to improve deposition efficiency.
Can not greatly affect the performance of battery due to negative current collector itself, substantially similar to execution mode one with the charging and discharging curve of battery that this execution mode is done.
Embodiment 4-3
The mode identical with embodiment 4-1 made battery, and different is as the battery porous layer with commercially available activated carbon fiber cloth.Microstructure and the activated carbon of this activity carbon cloth are similar, and thickness (not compression) is the 0.5mm left and right, and compression is rear between 0.1-0.2mm.The specific area of this activated carbon fiber cloth is 800m
2/ g.Activated carbon fiber cloth and negative current collector are cut into onesize, overlapping successively according to negative current collector-activated carbon fiber cloth-nonwoven fabrics barrier film-anode electrode.Structure with this battery that forms is identical with battery structure shown in Figure 15, and just the material of porous layer comprises activated carbon fiber cloth.Clearly, the battery that top method is made simple in structure can be carried out suitability for industrialized production at faster speed.The same with the porous layer that is comprised of activated carbon of mentioning in execution mode one and execution mode two, activated carbon fiber cloth also can provide enough large negative pole specific area.
Embodiment 5-1
With LiMn
2O
4Be positive active material, mix at 8: 1: 1 according to positive active material, active carbon black, bonding agent PVDF weight ratio, be cut into the disk of diameter 12mm, thickness 0.1-0.2mm, be compressed on the aluminium alloy collector, make positive pole.Negative pole is the metallic zinc of diameter 12mm, thickness 1mm, and metallic zinc doubles as negative electrode active material and negative current collector.Interval 5mm between positive and negative electrode, barrier film are filter paper.Electrolyte is to contain the lithium sulfate of 4mol/L lithium ion and 2mol/L zinc ion and the mixed aqueous solution of zinc sulfate, and the pH that adds the LiOH of 0.1mol/L to regulate electrolyte by titration is 5.
Battery is discharged and recharged, and voltage range is 1.4-2.4V, and sweep speed is 0.5mV/s.Plus plate current-collecting body aluminium alloy surface when high voltage 2.4V forms passivating film.
Embodiment 5-2
In embodiment 5-2, plus plate current-collecting body is the alloy foil of thickness 50 μ m, and negative pole is the metallic zinc paper tinsel of thickness 50 μ m, and electrolyte is 1.5mol/L Zn (Ac)
2With 2mol/L LiAc, barrier film is the glass felt-cloth, and all the other batteries compositions and method of testing are with embodiment 5-1.
Figure 21 and Figure 22 are respectively the CV curve chart of the battery that embodiment 5-1 and 5-2 provide.As can be seen from the figure, anode and negative electrode scanning each time be all to should have two significant oxidation peak (1.95V and 1.85V) and two reduction peak (1.85V and 1.7V), this with lithium ion deviating from organic bath/embed mechanism consistent.Except these two obvious oxidation-reduction pairs, less oxidation peak has also appearred after circulation primary, and peak current appears at 1.6V, and the cause of this oxidation peak may be deviating from-embedding of proton.This result has further been verified the stable fine of battery of the present invention, and has excellent charge-discharge performance.
In addition, the battery in embodiment 5-2 still near 90%, shows that the efficiency for charge-discharge of battery is very high in the enclosed pasture efficient of circulation after 600 times.
Embodiment 5-3
In embodiment 5-3, plus plate current-collecting body is the stainless steel 304 through transpassivation, and the thickness of stainless steel 304 is 50 μ m, and electrolyte is 2mol/L ZnSO
4With 2mol/L Li
2SO
4, barrier film is the glass felt-cloth, and all the other batteries form with embodiment 5-1, and the charging/discharging voltage interval is 1.4-2.1V.The concrete stainless method of passivation is: under 50 ℃, stainless steel is inserted 20% red fuming nitric acid (RFNA) and reach half an hour, make stainless steel surfaces form one deck passivating film.
Figure 23 is the CV curve of battery in embodiment 5-3.
Embodiment 5-4
In embodiment 5-4, plus plate current-collecting body is the stainless steel 304 through transpassivation, and electrolyte is 3mol/LZn (NO
3)
2With 6mol/L LiNO
3, all the other batteries form with embodiment 5-1, and the charging/discharging voltage interval is 1.4-2.2V.The concrete stainless method of passivation is with embodiment 5-3.
Figure 24 is the CV curve of battery in embodiment 5-4.
Embodiment 5-5
The mode identical with embodiment 5-1 made battery, difference is that 304 type stainless steels of the process Passivation Treatment take thickness as 1mm replace graphite foil as plus plate current-collecting body, concrete Passivation Treatment process is: under 50 ℃, stainless steel is inserted 20% nitric acid and reach half an hour, make stainless steel surfaces form one deck passivating film.Electrolyte is to contain the aqueous solution that concentration is 1.5mol/L zinc acetate and 3mol/L lithium acetate.Battery cathode is metallic zinc.Treat that battery pack installed standing 12 hours afterwards, began with the 1mA constant current, battery to be carried out charging and discharging subsequently.The charging/discharging voltage interval is 1.4-2.2V.
Embodiment 5-6
The mode identical with embodiment 5-1 made battery, and difference is that 316 type stainless steels with Passivation Treatment replace 304 type stainless steels as plus plate current-collecting body, and concrete Passivation Treatment process is with embodiment 5-5.Treat battery pack install after standing 12 hours, begin subsequently respectively with the constant current of 1mA and 3mA, battery to be carried out charging and discharging.The charging/discharging voltage interval is 1.4-2.2V.
Figure 25 is the CV curve of battery in embodiment 5-6.
Embodiment 5-7
The mode identical with embodiment 5-6 made battery, and difference is that electrolyte is to contain the aqueous solution that concentration is 3mol/L zinc sulfate and 3mol/L lithium sulfate.Treat battery pack install after standing 12 hours, begin subsequently respectively with the constant current of 1mA, 2mA, 3mA, battery to be carried out charging and discharging.The charging/discharging voltage interval is 1.4-2.2V.
Embodiment 5-8
The mode identical with embodiment 5-7 made battery, and difference is that metallic aluminium with Passivation Treatment is as plus plate current-collecting body.Process to the metallic aluminium Passivation Treatment is: treat that battery pack installed standing 12 hours afterwards, begin subsequently with the 1mA constant current, battery to be carried out charging and discharging, during charging, voltage all is charged to 2.4V, and namely the charging/discharging voltage interval is 1.4-2.4V, makes metallic aluminium surface formation one deck passivating film.
The capability retention test
By embodiment 5-1 is discharged and recharged operation to the battery in 5-8, to detect the cycle performance of battery.
Table 2 discharges and recharges under the 1mA constant current to the battery in 5-8 for embodiment 5-1, and the battery performance of 80 times circulates:
Table 2
As can be seen from Table 2, through the stainless steel of Passivation Treatment the battery performance during as plus plate current-collecting body from capability retention and efficiency for charge-discharge two aspects all than more excellent.
To the constant current charge-discharge test of embodiment 5-6 with 3mA, circulating, capability retention is 94% after 80 times, efficiency for charge-discharge is 98%, and battery performance is better than with 1mA constant current charge-discharge test result, illustrates that the battery in the present invention has excellent battery performance under large electric current.
Embodiment 5-7 with the test of the constant current charge-discharge of 2mA, 3mA, circulate that capability retention is respectively 92% and 72% after 80 times, and efficiency for charge-discharge is battery that 99%, embodiment 5-7 provides with battery performance the best of 2mA constant current charge-discharge.
Embodiment 5-9
With LiMn
2O
4Be positive active material, mix at 8: 1: 1 according to positive active material, active carbon black, bonding agent PVDF weight ratio, be coated on the stainless steel collector of passivation, make positive pole.The passivation for stainless steel method is with embodiment 5-3.Negative pole is the metallic zinc paper tinsel of thickness 50 μ m, and metallic zinc doubles as negative electrode active material and negative current collector.Barrier film is the glass felt-cloth.Electrolyte is the mixed aqueous solution that contains 2mol/L lithium acetate, 1.5mol/L zinc acetate and 1mol/L zinc sulfate, and regulating electrolyte pH is 5.
Battery is discharged and recharged, and voltage range is 1.4-2.1V, and sweep speed is 0.5mV/s.
The CV curve of the battery that Figure 26 provides for embodiment 5-9, experimental result show, battery near 100%, shows that the battery of employing mixed electrolyte salt has stable charge-discharge performance in the enclosed pasture efficient of circulation 200 times.
Embodiment 6-1
With LiMn
2O
4Be positive active material, positive active material, super-p carbon black, bonding agent PVDF are mixed according to part by weight at 83: 10: 7, as dispersant, make anode sizing agent with NMP, evenly be coated on the plus plate current-collecting body graphite foil of thickness 80 μ m, subsequent drying, compacting obtain positive pole.Negative pole is the metallic zinc paper tinsel of thickness 50 μ m, and metallic zinc is negative electrode active material, simultaneously the double negative current collector of doing also.Barrier film is the glass felt-cloth.Electrolyte is the deionized water solution that contains 3mol/L lithium chloride and 4mol/L zinc chloride, and the pH that regulates electrolyte by the LiOH solution that drips 0.1mol/L in electrolyte is 4.Under room temperature, battery is discharged and recharged with the 4C multiplying power at voltage range 1.5-2.1V.
Figure 27 is battery first charge-discharge in embodiment 6-1 and the relation curve of voltage, as can be seen from the figure battery first discharge capacity be about 0.35mAh.
Figure 28 is the relation curve of discharge capacity of the cell and cycle-index, and battery capacity of battery after circulation 1000 times still remains on more than 85%, and capacity attenuation is very little, shows that battery has extraordinary stability.
Figure 29 is the relation curve of battery enclosed pasture efficient and cycle-index, as can be seen from the figure battery in the enclosed pasture efficient of circulation after 1000 times more than 80%.
Embodiment 6-2
With LiMn
2O
4Be positive active material, positive active material, super-p carbon black, bonding agent PVDF are mixed according to part by weight at 83: 10: 7, as dispersant, make anode sizing agent with NMP, evenly be coated on the plus plate current-collecting body graphite foil of thickness 80 μ m, subsequent drying, compacting obtain positive pole.Negative pole is the metallic zinc paper tinsel of thickness 50 μ m, and metallic zinc is negative electrode active material, simultaneously the double negative current collector of doing also.Barrier film is non-woven fibre cloth.Electrolyte is the aqueous solution that contains 3mol/L lithium chloride and 4mol/L zinc chloride, and the pH that regulates electrolyte by the LiOH solution that drips 0.1mol/L in electrolyte is 4.Under room temperature, battery is discharged and recharged with the 1C multiplying power at voltage range 1.5-2.1V.
The discharge capacity of the battery that Figure 30 provides for embodiment 6-2 and the relation curve of cycle-index, battery capacity after circulation 30 times is slightly decayed, but rate of decay is very slow.
Figure 31 is the relation curve of battery enclosed pasture efficient and cycle-index, and battery is in the enclosed pasture efficient of circulation after 30 times nearly 90%.
Embodiment 6-3
With LiMn
2O
4Be positive active material, positive active material, super-p carbon black, bonding agent CMC-SBR are mixed according to part by weight at 83: 10: 7, with NMP as dispersant, make anode sizing agent, evenly be coated on the plus plate current-collecting body stainless steel foil of thickness 50 μ m, stainless steel is without passivation, and subsequent drying, compacting obtain positive pole.Negative pole is the metallic zinc paper tinsel of thickness 40 μ m, and metallic zinc is negative electrode active material, simultaneously the double negative current collector of doing also.Barrier film is the glass felt-cloth.Electrolyte is the aqueous solution that contains 1mol/L lithium acetate and 1.5mol/L zinc acetate, and the pH that regulates electrolyte by LiOH and the 0.1mol/L HAc solution of dropping 0.1mol/L in electrolyte is 4.Under room temperature, battery is discharged and recharged with the 0.5C multiplying power at voltage range 1.5-2.1V.
In embodiment 6-3, the battery experimental result shows, the discharge capacitance that circulating battery is 320 times and enclosed pasture efficient show that all near 100% battery has very excellent cycle performance and life-span.
Embodiment 6-4
In embodiment 6-4, battery is placed under 55 ℃ discharges and recharges, with research battery charge-discharge performance at high temperature, other compositions of battery and method of testing are with embodiment 6-3.
The discharge capacity of the battery that Figure 32 provides for embodiment 6-4 and the relation curve of cycle-index, as can be seen from the figure, battery still has good discharge capacitance under 55 ℃ of high temperature, and circulating battery does not almost have obvious capacity attenuation 160 times.
Embodiment 6-5
With LiMn
2O
4Be positive active material, positive active material, super-p carbon black, bonding agent PVDF are mixed according to part by weight at 83: 10: 7, with NMP as dispersant, make anode sizing agent, evenly be coated on the plus plate current-collecting body stainless (steel) wire of thickness 30 μ m, stainless steel is without passivation, and subsequent drying, compacting obtain positive pole.Negative pole is the metallic zinc paper tinsel of thickness 10 μ m, and metallic zinc is negative electrode active material, simultaneously the double negative current collector of doing also.Barrier film is the glass felt-cloth.Electrolyte is the aqueous solution that contains 1mol/L lithium acetate and 1.5mol/L zinc acetate, and the pH that regulates electrolyte by LiOH and the 0.1mol/L HAc solution of dropping 0.1mol/L in electrolyte is 4.Under room temperature, battery is discharged and recharged with the 0.5C multiplying power at voltage range 1.5-2.1V.
The discharge capacity of the battery that Figure 33 provides for embodiment 6-5 and the graph of relation of cycle-index, as can be seen from the figure, 30 discharge capacities of circulating battery are not decay almost, shows that battery charging and discharging stability provided by the invention is good.
Embodiment 7-1
With LiMn
2O
4Be positive active material, with positive active material, super-p carbon black, bonding agent PVDF according to part by weight 8: 1: mix, as dispersant, make anode sizing agent with NMP, evenly be coated on the plus plate current-collecting body graphite foil of thickness 80 μ m, subsequent drying, compacting obtain positive pole.Negative current collector is the graphite foil of thickness 50 μ m, and metallic zinc is plated on graphite foil as negative electrode active material.Barrier film is the glass felt-cloth.Electrolyte is the aqueous solution that contains 2mol/L lithium acetate and 1.5mol/L zinc acetate, and the pH that regulates electrolyte by the LiOH solution that drips 0.1mol/L in electrolyte is 4.Under room temperature, battery is discharged and recharged with the 0.5C multiplying power at voltage range 1.5-2.1V.
Embodiment 7-2
The mode identical with embodiment 7-1 made battery, and difference is that 316 type stainless steels replace graphite foil as negative current collector.
Embodiment 7-3
The mode identical with embodiment 7-1 made battery, and difference is that Copper Foil replaces graphite foil as negative current collector.
The battery that embodiment 7-1 provides to 7-3, battery have good cycle performance.
Although the inventor has done more detailed elaboration and has enumerated technical scheme of the present invention, be to be understood that, to those skilled in the art, above-described embodiment is modified and/or flexible or to adopt the replacement scheme that is equal to be obvious, all can not break away from the essence of spirit of the present invention, the term that occurs in the present invention is used for elaboration and the understanding to technical solution of the present invention, can not be construed as limiting the invention.