KR101308096B1 - Anode for rechargeable lithium thin film battery, method of preparing thereof, and rechargeable lithium thin film battery comprising the same - Google Patents

Abstract

The present invention relates to a negative electrode for a lithium secondary thin film battery, a method for manufacturing the same, and a lithium secondary thin film battery including the same, and more particularly, a silicon-metal active layer including a metal that reacts with silicon without reacting with lithium, and the silicon A negative electrode thin film including a metal layer or a silicon-metal layer having a low silicon concentration on the metal active layer, and including a multilayer thin film in which the silicon-metal active layer and the buffer layer are alternately stacked, and a method of manufacturing the same. And it relates to a lithium secondary thin film battery comprising the same.

The negative electrode of the multilayer thin film structure prevents mechanical cracking occurring in the conventional negative electrode thin film by controlling the volume change when silicon generated during the charge and discharge reaction with lithium, so that the chemical As the mechanical stability is greatly improved, the life characteristics of the lithium secondary thin film battery are improved.

Thin Film Cell, Silicon, Multilayer Cathode Thin Film

Description

Anode for a lithium secondary thin film battery, a method of manufacturing the same, and a lithium secondary thin film battery including the same.

1A is a cross-sectional view of a cathode including a multilayer thin film structure in which a silicon-metal (Si-Ma) active layer and an alloy (Ma-Mb) layer are alternately stacked.

1B is a cross-sectional view of a cathode including a multilayer thin film structure in which a silicon-alloy (Si-Ma-Mb) active layer and a metal (Ma) layer are alternately stacked.

1C is a cross-sectional view of a cathode including a multilayer thin film structure in which a silicon-alloy (Si-Ma-Mb) active layer and an alloy (Ma-Mb) layer are alternately stacked.

FIG. 2A is a cross-sectional view of a cathode including a multilayer thin film structure in which a silicon-metal (Si-Ma) active layer and a low silicon concentration silicon-metal layer (Si′-Ma) are alternately stacked.

2B is a cross-sectional view of a cathode including a multilayer thin film structure in which a silicon-alloy (Si-Ma-Mb) active layer and a low silicon concentration silicon-metal (Si'-Ma) layer are alternately stacked.

FIG. 2C is a cross-sectional view of a cathode including a multilayer thin film structure in which a silicon-metal (Si-Ma) active layer and a low silicon concentration (Si'-Ma-Mb) layer are alternately stacked.

2D is a cross-sectional view of a cathode including a multilayer thin film structure in which a silicon-alloy (Si-Ma-Mb) active layer and a low silicon concentration (Si'-Ma-Mb) layer are alternately stacked.

3 is an electrically insulating substrate; Anode current collector; anode; Solid electrolytes; cathode; Cathode current collector; And a cross-sectional view of a lithium secondary thin film battery having a structure in which protective films are sequentially stacked.

4 is an electrically conductive substrate or anode current collector; anode; Solid electrolytes; cathode; Cathode current collector; And a cross-sectional view of a lithium secondary thin film battery having a structure in which protective films are sequentially stacked.

5 is an electrically insulating substrate; Cathode current collector; cathode; Solid electrolytes; anode; Anode current collector; And a cross-sectional view of a lithium secondary thin film battery having a structure in which protective films are sequentially stacked.

6 is an electrically conductive substrate or cathode current collector; cathode; Solid electrolytes; anode; Anode current collector; And a cross-sectional view of a lithium secondary thin film battery having a structure in which protective films are sequentially stacked.

Figure 7 is a graph showing the charge and discharge capacity change according to the cycle of the battery comprising a negative electrode film prepared in Example 1 of the present invention.

8 is a graph showing the charge-discharge capacity change according to the cycle of the battery including the negative electrode film prepared in Example 2 of the present invention.

9 is a graph showing a change in discharge capacity according to the cycle of the thin film battery prepared in Example 4 of the present invention.

10 is a charge and discharge graph of the first cycle of the thin film battery prepared in Example 4 of the present invention.

11 is a graph showing the change in discharge capacity according to the cycle of the thin film battery prepared in Example 5 of the present invention.

12 is a charge and discharge graph of the first cycle of the thin film battery prepared in Example 5 of the present invention.

The present invention relates to a negative electrode for a lithium secondary thin film battery, a method for manufacturing the same, and a lithium secondary thin film battery including the same. More specifically, the silicon thin film battery generated during the charge / discharge process controls the volume change when reacting with a lithium thin film machine. A negative electrode for a lithium secondary thin film battery, a method of manufacturing the same, and a lithium secondary thin film battery comprising the same, by improving the chemical and mechanical stability of the interface between the negative electrode and the solid electrolyte layer by preventing a crack, thereby improving the life characteristics of the lithium secondary thin film battery. It is about.

Thin film batteries are expected to be greatly used as miniature power supply systems for driving them as portable electronic devices and information and communication devices are miniaturized. Moreover, in recent years, development and research of polymer electronic devices and devices using advantages such as flexibility, low cost, and ease of manufacture have been actively conducted. Therefore, it is necessary to develop a technology for forming a thin film battery on a substrate with flexibility characteristics including a polymer.

In such a thin film battery, lithium transition metal oxides such as LiCoO ₂ and LiMn ₂ O ₄ are used as the positive electrode active material, and lithium metal has been mainly used as the negative electrode active material. However, lithium metal is highly reactive with oxygen and moisture in the air, which makes the deposition process complicated and difficult to handle the manufactured thin film battery. In addition, lithium metal has a low melting point (181 ℃) has a problem that the use is limited.

On the other hand, to overcome the above problems, a tin oxide-based (tin oxide and its derivatives) negative active material was used. However, a problem arises that an initial irreversible reaction in which lithium is consumed occurs because the cathode oxide is reduced by lithium ions during the initial charging reaction. The initial irreversible lithium loss should be minimized since lithium is supplied from the lithium transition metal oxide anode during the initial charge reaction.

Silicon (Si) reacts with a large amount of lithium in a low voltage range with respect to lithium, and is used as a negative electrode active material because lithium can be reversibly inserted and detached. However, due to the large volume change of Si during insertion and desorption of lithium during charging and discharging, mechanical stress may occur and degradation of the thin film anode may occur.

Furthermore, when the negative electrode thin film is used in an all-solid-state thin-film battery, the adhesion between the electrolyte and the negative electrode is lowered, and the lifespan characteristics of the battery are greatly reduced.

The present inventors have a current collector and a negative electrode active material layer formed thereon to supplement the above problems of silicon, and as a negative electrode thin film for a lithium secondary thin film battery, without reacting with lithium, silicon in a matrix made of a metal that reacts with silicon The dispersed silicon-metal active layer and a negative electrode film for a lithium secondary battery, which is a multilayer thin film in which a metal layer reacting with silicon without reacting with lithium, are alternately stacked and registered with Korean Patent No. 563081.

On the other hand, the positive electrode thin film for a lithium secondary battery is manufactured by depositing a lithium transition metal oxide (for example, LiCoO ₂ ) by the same method as sputtering. In general, the lithium transition metal oxide is known to have excellent lithium insertion-desorption reaction and electrical conductivity in a well-developed state of crystallinity. To this end, the process includes a heat treatment at a high temperature of about 700 ℃ after deposition. However, the heat treatment process at such a high temperature is not suitable for the process including the negative electrode active material, since the charge and discharge reversible capacity is greatly reduced in the case of the negative electrode thin film to be used in the present invention at a temperature of 400 ° C. or higher. not.

Therefore, it is necessary to develop a method for manufacturing a thin film battery having excellent and stable characteristics as a thin film battery including the negative electrode thin film without significantly reducing the lithium storage capacity of the negative electrode thin film.

In order to solve the above problems, an object of the present invention is to control the volume change when the silicon generated during the charge and discharge reaction with lithium negative electrode for a lithium secondary thin film battery to prevent mechanical cracking occurring in the conventional negative electrode thin film and It is to provide a preparation method thereof.

In addition, another object of the present invention is to provide a lithium secondary thin film battery having improved life characteristics as the chemical and mechanical stability of the interface between the anode and the solid electrolyte membrane is greatly improved, including the cathode of the multilayer thin film structure.

In order to achieve the above object,

(a) a silicon-metal active layer comprising a metal that reacts with silicon without reacting with lithium,

(b) a cathode thin film including a metal layer or a silicon-metal layer having a low silicon concentration on the silicon-metal active layer,

Provided is a negative electrode for a lithium secondary thin film battery including a multilayer thin film in which the silicon-metal active layer and the buffer layer are alternately stacked.

Also,

(i) forming a buffer layer of either a metal layer or a silicon-metal layer having a low silicon concentration on the substrate,

(ii) a method of manufacturing a negative electrode for a lithium secondary thin film battery which performs at least one or more steps of forming a silicon-metal active layer on the buffer layer.

In another aspect, the present invention provides a lithium secondary thin film battery comprising a negative electrode of the multilayer thin film structure.

Hereinafter, the present invention will be described in more detail.

Silicon originally exhibits a large capacity in the low voltage range with respect to lithium (Li) and reacts with lithium according to the following equation.

Si + 4.4 Li ↔ Li _{4 .4} Si

Although the energy density of silicon is 9320 mAh / cm 3, it has many advantages such as a very large capacity, and as the charge and discharge process proceeds, lithium is repeatedly inserted and desorbed, causing volume expansion and contraction of silicon particles to be cracked. It breaks while it happens. As a result, a problem arises in that the silicon particles which are not in electrical contact with each other generate charge and discharge capacities, thereby limiting their use as a negative electrode active material.

Accordingly, the present invention provides a cathode having a multilayer thin film structure that prevents mechanical cracking occurring in a conventional cathode thin film. The negative electrode of the multi-layered thin film structure has the disadvantages of silicon, that is, to relieve the stress caused by the volume expansion of silicon and structurally improve the stability of the negative electrode active material layer has the effect of improving the charge and discharge characteristics. As a result, it is possible to control the volume change when silicon generated during the charge and discharge reaction with lithium. In addition, as the chemical and mechanical stability of the interface between the anode and the solid electrolyte layer is greatly improved, there is an advantage that the life characteristics are improved.

In this case, the cathode has a structure of a multilayer thin film in which a silicon-metal active layer and a buffer layer are alternately stacked. As used herein, the term "alternatively" is used to mean that two layers are formed alternately with each other and any one of the two layers may be started first.

In this case, the buffer layer may be a metal layer or a silicon-metal layer having a low silicon concentration, and each case will be described in more detail below.

(a) When the buffer layer is a metal layer

The cathode of the multilayer thin film structure according to the first preferred embodiment of the present invention forms a buffer layer by depositing a metal layer on a substrate, and simultaneously forms a silicon-metal active layer by depositing metal together with silicon on the buffer layer. The negative electrode comprising the buffer layer and the silicon-metal active layer is preferably manufactured so that the metal layer is located on the top.

The silicon-metal active layer is represented by the following Chemical Formula 1:

Si _1-x -M _x

In Formula 1, M _x is Ma or Ma-Mb,

In this case, Ma is titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zirconium (Zr), niobium ( Nb), molybdenum (Mo), thallium (Ta), tungsten (W), hafnium (Hf), rhenium (Re) and one kind of metal selected from the group consisting of

Mb is one metal selected from the group consisting of silver (Ag), gold (Au), aluminum (Al), zinc (Zn), tin (Sn), antimony (Sb), and combinations thereof,

x is a real number from 0.2 to 0.5.

Such a silicon-metal active layer has a strong chemical affinity between silicon and metal in the structure, thereby limiting the amount of reaction between silicon and lithium during the reaction with lithium, so that structural stability is expected to be higher than that of pure silicon during repeated lithium insertion and desorption processes. .

Specifically, in the case of Ma metal, the volume expansion of the silicon itself is alleviated and the electrical conductivity of the silicon is improved. In addition, in the case of Mb metal, it is possible to further improve the electrical conductivity of the negative electrode having a multi-layered thin film structure, thereby further improving the buffering property against mechanical cracking during the charge and discharge reaction.

Preferably, the silicon-metal active layer may be a 'silicon-metal active layer' using Ma alone or a 'silicon-alloy active layer' using Ma-Mb alloy.

In this case, x is 0.2 to 0.5 is preferably present in the same or higher concentration than the metal. If x exceeds the above range, many metal atoms are surrounded around the fine particles of silicon, which is a reactive active material with lithium, and the silicon is shielded by the surrounding metal. As a result, the silicon atoms cannot react with lithium, so that the electrode capacity is much lower than the actual designed capacity.

The metal layer formed on the silicon-metal active layer may be any one metal of Ma metal or Ma-Mb alloy. In this case, Ma is titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zirconium (Zr), niobium ( Nb), molybdenum (Mo), thallium (Ta), tungsten (W), hafnium (Hf), rhenium (Re), and one metal selected from the group consisting of a combination thereof, Mb is silver (Ag), gold One metal selected from the group consisting of (Au), aluminum (Al), zinc (Zn), tin (Sn), antimony (Sb), and combinations thereof is possible.

In the present specification, the metal layer includes both the 'metal layer' using Ma alone or the 'alloy layer' using Ma-Mb alloy.

The metal layer does not react with lithium and maintains a metal bond with silicon at the interface with the silicon-metal active layer. The metal layer acts as a medium through which lithium ions can move together with the electrons, and serves to buffer the stress that may occur during the lithium-silicon reaction, thereby securing stability of the active material structure.

However, when M _x of the silicon-metal active layer is Ma, the metal layer is preferably formed of an alloy of Ma-Mb.

1A to 1C are cross-sectional views showing the structure of an active layer of silicon-metal or silicon-alloy and a cathode in which a metal layer or an alloy layer is laminated as a buffer layer. In this case, the case of using Ma alone as a metal layer, and the case of using Ma-Mb, is referred to as an 'alloy layer' for better understanding of the drawings.

Specifically, FIG. 1A is a cross-sectional view of a cathode including a multilayer thin film structure in which a silicon-metal active layer and an alloy layer are alternately stacked.

Referring to FIG. 1A, in the cathode of a multilayer thin film structure, an alloy layer (Ma-Mb, 103a) is formed on a substrate or a cathode current collector 101, and a silicon-metal active layer (Si−) is formed on the alloy layer 103a. Ma and 105a are formed, the alloy layer 103a and the silicon-metal active layer 105a are sequentially stacked on top of each other, and the alloy layer 103a is stacked on the uppermost layer.

1B is a cross-sectional view of a cathode including a multilayer thin film structure in which a silicon-alloy active layer and a metal layer are alternately stacked.

Referring to FIG. 1B, the cathode of the multilayer thin film structure includes metal layers Ma and 103b formed on a substrate or an anode current collector 101, and a silicon-alloy active layer Si-Ma-Mb, formed on the metal layer 103b. 105b) is formed, the metal layer 103b and the silicon-alloy active layer 105b are sequentially stacked on top of each other, and the metal layer 103b is stacked on the top layer.

1C is a cross-sectional view of a cathode including a multilayer thin film structure in which a silicon-alloy active layer and an alloy layer are alternately stacked.

Referring to FIG. 1C, in the cathode of the multilayer thin film structure, an alloy layer (Ma-Mb, 103a) is formed on a substrate or an anode current collector 101, and a silicon-alloy active layer (Si-) is formed on the alloy layer 103a. Ma-Mb and 105b are formed, the alloy layer 103a and the silicon-alloy active layer 105b are sequentially stacked on top of each other, and the alloy layer 103a is stacked on the uppermost layer.

(b) the buffer layer is a silicon-metal layer having a low silicon concentration

In the cathode of the multilayer thin film structure according to the second preferred embodiment of the present invention, a silicon-metal active layer is formed by simultaneously depositing metal together with silicon, and the concentration of silicon is higher than the silicon-metal active layer on the silicon-metal layer as a buffer layer. Prepared by depositing a low silicon-metal layer.

The silicon-metal layer having a low silicon concentration is represented by the following Chemical Formula 2:

Si _1-y -M _y

In Formula 2, M _y is Ma or Ma-Mb,

In this case, Ma is titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zirconium (Zr), niobium ( Nb), molybdenum (Mo), thallium (Ta), tungsten (W), hafnium (Hf), rhenium (Re) and one kind of metal selected from the group consisting of

Mb is one metal selected from the group consisting of silver (Ag), gold (Au), aluminum (Al), zinc (Zn), tin (Sn), antimony (Sb), and combinations thereof,

y is a real number between 0.4 and 1.0.

The silicon-metal layer having a low silicon concentration has an effect of increasing the diffusion rate of lithium ions during charging and discharging. In this case, the content of the metal in the silicon-metal (Si _1-y -M _y ) layer having a low concentration of silicon is preferably in the range of 0.4 <y <1.0. If y is less than the above range, it causes a problem that the stress relaxation effect to the buffer layer is insufficient.

In this specification, the silicon-metal layer having a low silicon concentration includes both a 'low silicon concentration silicon-metal layer' using Ma as a metal or a 'low silicon concentration silicon-alloy layer' used as an alloy of Ma-Mb.

2A to 2D are cross-sectional views illustrating a cathode of a multilayer thin film structure according to a second embodiment. In this case, the case of using Ma alone as a metal layer, and the case of using Ma-Mb, is referred to as an 'alloy layer' for better understanding of the drawings.

Specifically, FIG. 2A is a cross-sectional view of a cathode including a multilayer thin film structure in which a silicon-metal active layer and a silicon-metal layer having a low silicon concentration are alternately stacked.

Referring to FIG. 2A, the cathode of the multilayer thin film structure has a silicon-metal layer (Si′-Ma, 203a) having a low silicon concentration formed on a substrate or a cathode current collector 201, and the silicon-metal layer having a low silicon concentration ( A silicon-metal active layer (Si-Ma, 205a) is formed on 203a, and a silicon-metal layer 203a and a silicon-metal active layer 205a having a low silicon concentration are sequentially stacked on top of the silicon-metal active layer (Si-Ma, 205a). The silicon-metal layer 203a having a low concentration is laminated.

FIG. 2B is a cross-sectional view of a negative electrode including a multilayer thin film structure in which a silicon-alloy active layer and a low silicon concentration silicon-metal layer are alternately stacked.

Referring to FIG. 2B, in the cathode of the multilayer thin film structure, a silicon-metal layer (Si′-Ma) 203a having a low silicon concentration is formed on a substrate or a cathode current collector 201, and the silicon-metal layer having a low silicon concentration ( A silicon-alloy active layer (Si-Ma-Mb, 205b) is formed on 203a, a silicon-metal layer 203a and a silicon-alloy active layer 205b having a low silicon concentration are sequentially stacked on top of each other, and a top layer is formed. Has a structure in which a silicon-metal layer 203a having a low silicon concentration is laminated.

2C is a cross-sectional view of a cathode including a multilayer thin film structure in which a silicon-metal active layer and a silicon-alloy layer having a low silicon concentration are alternately stacked.

Referring to FIG. 2C, in the cathode of the multilayer thin film structure, a silicon-alloy layer (Si′-Ma-Mb, 203b) having a low silicon concentration is formed on a substrate or a cathode current collector 201, and the silicon concentration is low. A silicon-metal active layer (Si-Ma, 205a) is formed on the alloy layer 203b, and a silicon-alloy layer 203b and a silicon-metal active layer 205a having a low silicon concentration are sequentially stacked thereon. The silicon-alloy layer 203b having a low silicon concentration is stacked on the uppermost layer.

2D is a cross-sectional view of a cathode including a multilayer thin film structure in which a silicon-alloy active layer and a silicon-alloy layer having a low silicon concentration are alternately stacked.

In the cathode of the multilayer thin film structure according to FIG. 2D, a silicon-alloy layer (Si′-Ma-Mb, 203b) having a low silicon concentration is formed on a substrate or a cathode current collector 201, and the silicon-alloy having a low silicon concentration is formed. A silicon-alloy active layer (Si-Ma-Mb, 205b) is formed on the layer (Si'-Ma-Mb, 203b), and the silicon-alloy layer 203b and the silicon-alloy active layer having a low silicon concentration are formed thereon. 205b) is sequentially stacked, and a silicon-alloy layer 203b having a low silicon concentration is stacked on the top layer.

As described above, the cathode of the multilayer thin film structure according to the present invention includes a multilayer thin film in which a silicon-metal active layer and a buffer layer of a metal layer or a silicon-metal layer having a low silicon concentration are alternately stacked. At this time, it is preferable that the uppermost layer of the cathode of the multilayer thin film structure is made of a metal layer or a silicon-metal layer having a low silicon concentration.

Preferably, since the thickness of the silicon-metal active layer and the number of stacked layers of the negative electrode of the multilayer thin film structure according to the present invention are proportional to the amount of the negative electrode active material, the negative electrode may be variously changed according to the requirements of the device and the capacity of the positive electrode. It is preferable that it is the range of 5000 kPa. If the thickness of the silicon-metal active layer exceeds the above range, there is a problem that the buffer layer does not sufficiently suppress the volume expansion of silicon. If the silicon-metal active layer is less than the above range, the total number of the multilayer thin films is increased to design the required capacity. Increasing above a predetermined range, there is a problem that the over-voltage (over potential) of the cathode having a multi-layer thin film structure increases.

In addition, the buffer layer is preferably formed in a range of 10 to 500 kPa and deposited to a minimum thickness capable of acting as a medium through which lithium ions can move together with electrons and to mitigate the volume change of the silicon-metal active layer. If the thickness of the buffer layer is less than the range, the effect of suppressing the volume change of the silicon-metal active layer is small. On the contrary, if the thickness exceeds the range, it is difficult to move lithium ions through the buffer layer.

As described above, the cathode of the multilayer thin film structure in which the silicon-metal active layer and the buffer layer are alternately stacked has a thickness of 0.1 μm to 3 μm, and the silicon-metal active layer and the buffer layer are laminated in at least two layers, up to 500 layers. do.

The cathode of the multilayer thin film structure

(i) forming a buffer layer of a metal layer or a silicon-metal layer having a low silicon concentration on the substrate,

(ii) forming the silicon-metal active layer on the buffer layer at least once or more.

In this case, the silicon-metal active layer, the metal layer, and the buffer layer of the silicon-metal layer having a low silicon concentration are typically magnetron sputtering, DC diode sputtering, electron beam vapor deposition, and electron beam vapor deposition used in the art. It is formed by performing one method selected from the group consisting of ion beam sputtering.

In this case, after the heat treatment, the interfacial bonding strength between layers may be increased through the DC bias process as described above, and the bonding strength of the interface may be increased through the process of heating the substrate, the ion beam irradiation process, or the plasma treatment process, as well as ensuring the safety of the interface. Etc. physical properties of the interface can be improved.

The negative electrode of the multilayer thin film structure having the above structure is applied as a negative electrode of the lithium secondary thin film battery to prevent mechanical cracking occurring in the conventional negative electrode thin film, thereby greatly improving the chemical and mechanical stability of the interface between the negative electrode and the solid electrolyte membrane. Accordingly, the life characteristics of the lithium secondary thin film battery are improved.

At this time, the charge / discharge cycle characteristics of the lithium secondary thin film battery are characterized by the thickness and arrangement order of the silicon-metal active layer and the metal layer or the silicon-metal layer having low silicon concentration, the overall thickness of the cathode, the thin film formation conditions, and the silicon and metal. Various properties can be expected by controlling the stability of the laminated structure by the mixing ratio and the like.

3 is a cross-sectional view schematically showing the structure of a lithium secondary thin film battery. The structure of the lithium secondary thin film battery applied at this time is not particularly limited in the present invention, and all of the structures commonly used in this field are possible.

Referring to FIG. 3, a lithium secondary thin film battery may include an electrically insulating substrate; Anode current collector; anode; Solid electrolytes; cathode; Cathode current collector; And a protective film sequentially stacked.

The substrate 2 may be an insulating substrate having flexibility characteristics including a polymer.

The positive electrode current collector 4 is not particularly limited as long as it has high conductivity without causing chemical change in the battery. For example, silver (Ag), gold (Au), platinum (Pt), palladium (Pd), aluminum (Al), nickel (Ni), copper (Cu), titanium (Ti), vanadium (V), chromium One selected from the group consisting of (Cr), iron (Fe), cobalt (Co), manganese (Mn), stainless steel, and combinations thereof may be used. The positive electrode current collector 4 may increase the adhesion of the positive electrode active material by forming minute unevenness on the surface as necessary, and may be in various forms such as a film, a sheet, a foil, a net, a porous body, a foam, and a nonwoven fabric. In this case, the substrate 2 may be selectively unused according to the material of the anode current collector 4.

The anode 6 is preferably a lithium metal oxide layer laminated on any one pair of electrically conductive active layers. The electrically conductive active layer includes silver (Ag), gold (Au), platinum (Pt), palladium (Pd), copper (Cu), carbon (C), cobalt (Co), and these alloys, and Ti, Cr, HF Ni, Mo, Nb, V, Ta, Zr, and at least one selected from the group consisting of a combination of the group consisting of RuO ₂ and Li ₂ RuO ₃ , including one selected from the group consisting of 5 to It is preferable that it is 1 micrometer.

In addition, the lithium oxide layer is LiCoO ₂ , LiMn ₂ O ₄ , LiNiO ₂ , LiCo _{1 -x} Ni _x O ₂ (0.2 <x <0.8), LiM _y Mn _{2 - y} O ₄ (where M is Cr, Ni, Co , Al, Fe, Cu, Mg and one selected from the group consisting of a combination thereof, 0.2 <y <1.8.), Li ₂ MMn ₃ O ₈ (where M is Co or Fe), LiFePO ₄ , LiVOPO ₄ and at least one selected from the group consisting of a mixture, it is preferable to form a thickness of 0.5 to 3.0 ㎛. The lithium oxide layer exhibits a charge / discharge capacity close to a theoretical capacity in a nano-crystalline state, and when the heat treatment is performed at a temperature of about 300 ° C. after deposition, electrochemical properties as an anode are further improved.

The electrically conductive active layer and the lithium oxide layer of the anode 6 are formed in a thin film form by a deposition method, and are typically magnetron sputtering, pulsed laser deposition, and ion beam sputtering. After the deposition by one method selected from the group consisting of, prepared by low-temperature heat treatment of 300 ℃ or less.

The solid electrolyte 8 may be a material that is not reactive with an electrolyte, has lithium ion conductivity, and is not electrically conductive, and typically includes lithium phosphorous oxynitride (LiPON), lithium silicon phosphorous oxynitride (LiSiPON), lithium silicon oxynitride (LiSiON), and LiBPON. (lithium boron phosphorous oxynitride) and one inorganic electrolyte selected from the group consisting of, polyethylene derivatives, polyethylene oxide derivatives, polypropylene oxide derivatives, phosphate ester polymers, agitation lysine, polyester sulfide One type of polymer electrolyte is selected from the group consisting of: fused, polyvinyl alcohol, polyvinylidene fluoride, polymers containing ionic dissociation groups, and combinations thereof.

The solid electrolyte 8 acts as a protective film on the surface of the positive electrode where the positive electrode material and the electrolyte mainly react to reduce the reaction of the positive electrode material and the electrolyte, so that the battery performance is not deteriorated compared to a battery using only the solid electrolyte as the electrolyte. The battery life can be improved by lowering the degree of dissolution of the positive electrode material in the electrolyte solution as well as improving the safety of the battery.

The solid electrolyte 8 is manufactured in the form of a thin film, and the thin film material is formed into a gel by a vapor deposition method such as chemical vapor deposition (CVD) and sputtering, or a sol-gel method and then spin- Wet coating methods such as spin coating are formed.

At this time, the cathode 10 is a multilayer thin film cathode having a structure shown in Figures 1a to 2d.

The cathode current collector 12, like the cathode current collector 4, is not particularly limited as long as it has conductivity without causing chemical changes in the battery. Film, sheet, foil, net, porous material, foam, nonwoven fabric It can be used in various forms such as a sieve.

The protective film 14 isolates the battery from the atmosphere, and typically does not chemically react with Li such as ceramic, metal, paraline-metal or para-metal-ceramic thin films, chromium, nickel, and vanadium. Metal films stable, such as metal films, nitrides or oxides, or polymer compounds such as paralines, which are stable in the atmosphere, are possible.

4 shows an electrically conductive substrate 22 or a positive current collector 22; Anode 26; Solid electrolyte 28; Cathode 30; Cathode current collector 32; And a cross section of a lithium secondary thin film battery having a structure in which protective films 34 are sequentially stacked.

An electrically conductive substrate is used as the substrate 22, which plays the same role as the anode current collector. The substrate 22 may include copper (Cu), nickel (Ni), titanium (Ti), vanadium (V), chromium (Cr), iron (Fe), cobalt (Co), molybdenum (Mo), and niobium (Nb). ), Thallium (Ta), tungsten (W), stainless steel, and combinations thereof.

At this time, each component of the battery is as described in the third embodiment.

5 shows an electrically insulating substrate 42; Cathode current collector 52; Cathode 50; Solid electrolyte 48; An anode 46; Anode current collector 44; And a lithium secondary thin film battery having a structure in which protective films 54 are sequentially stacked. At this time, each component of the battery is as described above.

6 shows an electrically conductive substrate 62 or cathode current collector 62; Cathode 70; Solid electrolyte 68; Anode 66; Anode current collector 64; And a lithium secondary thin film battery having a structure in which the protective film 74 is sequentially stacked.

The electrically conductive substrate used as the substrate 62 of the lithium secondary thin film battery can be used as a cathode current collector. At this time, each component of the battery is as described above.

Meanwhile, the lithium secondary thin film battery of the present invention includes an additional diffusion barrier layer at the interface between the cathode and the electrolyte, or between the anode and the electrolyte to suppress excessive cross diffusion at each interface during deposition or post-deposition heat treatment. Can be.

The diffusion barrier layer is selected from the group consisting of Au, Ag, Pt, Pd, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zr, Nb, Mo, Ta, W, Hf, Re, and combinations thereof At least one metal or alloy; Nitrides including one selected from the group consisting of Ti, Cr, HF, Mo, Nb, V, Ta, Zr, and combinations thereof; RuO ₂ ; Li ₂ RuO ₃ ; and combinations thereof. The diffusion barrier layer is preferably formed in a thickness of 10 kPa to 500 kPa.

In this case, in addition to the diffusion barrier layer, a lithium composite metal compound layer may be included between the negative electrode and the electrolyte to react with lithium ions during charge and discharge and to reduce initial irreversibility by using good charge and discharge efficiency.

Examples of the compound included in the lithium composite metal compound layer include Li _{3 - x} M _x N (wherein M is one selected from the group consisting of Co, Cu, Ni, and combinations thereof, and 0≤x≤0.5), Li ₄ One selected from the group consisting of Ti ₅ O ₁₂ and a combination thereof is possible, and a chemical affinity is imparted to the interface between the cathode and the electrolyte by forming a layer having a thickness of 10 kPa to 500 kPa between the cathode and the electrolyte.

Hereinafter, examples of the present invention will be described. However, the following examples are merely examples of the present invention and the present invention is not limited to the following examples.

(Example)

(Example 1)

A cathode having a multilayer thin film structure was prepared by laminating a Zr thin film (buffer layer: metal layer) and a Si ₇₀ -Zr ₁₇ -Ag ₁₃ thin film (silicon-metal active layer) on a Ni substrate using a sputtering method.

At this time, the initial vacuum degree during deposition was maintained at 2.0 × 10 ⁻⁶ torr or less, and the deposition pressure was maintained at 5 m Torr in Ar atmosphere during deposition. The Zr thin film was deposited at a thickness of 100 kHz and the Si ₇₀ -Zr ₁₇ -Ag ₁₃ thin film was deposited at a thickness of 500 kHz.

(Example 2)

A negative electrode having a multilayer thin film structure was fabricated by stacking a Si ₅₈ -Zr ₄₂ thin film (buffer layer: a silicon-metal layer containing low concentration of silicon) and a Si ₈₅ -Zr ₁₅ thin film (silicon-metal active layer) on a Ni substrate. The conditions were carried out in the same manner as in Example 1.

The Si ₅₈ -Zr ₄₂ thin film was deposited to a thickness of 100 GPa, and the Si ₈₅ -Zr ₁₅ thin film was deposited to a thickness of 250 GPa.

(Example 3)

A Zr thin film (buffer layer: metal layer) was formed on a Ni substrate, and a Si ₇₀ -Zr ₁₇ -Ag ₁₃ thin film (silicon-metal active layer) and a Si ₅₀ -Zr ₄₁ -Ag ₉ thin film (buffer layer: low concentration silicon) were formed on top of the Ni substrate. Containing a silicon-metal layer) sequentially and the Si ₇₀ -Zr ₁₇ -Ag ₁₃ thin film and the Si ₅₀ -Zr ₄₁ -Ag ₉ thin film were sequentially stacked on top of each other to prepare a cathode having a multilayer thin film structure. Deposition conditions were performed in the same manner as in Example 1.

At this time, the Zr thin film is 100 Å thick, Si ₇₀ -Zr ₁₇ -Ag ₁₃ The thin film was deposited to a thickness of 500 mm 3 and the thin film of Si ₅₀ -Zr ₄₁ -Ag ₉ to 100 mm thick.

Table 1 shows the laminated structure of the cathode of the multilayer thin film structure of Examples 1 to 3.

Cathode laminated structure Example 1 Zr / Si ₇₀ -Zr ₁₇ -Ag ₁₃ ⁽¹⁾ / Zr / Si ₇₀ -Zr ₁₇ -Ag ₁₃ ⁽²⁾ / Zr / Si ₇₀ -Zr ₁₇ -Ag ₁₃ ⁽³⁾ / Zr / Si ₇₀ -Zr _17- Ag ₁₃ ⁽⁴⁾ / Zr / Si ₇₀ -Zr ₁₇ -Ag ₁₃ ⁽⁵⁾ / Zr / Si ₇₀ -Zr ₁₇ -Ag ₁₃ ⁽⁶⁾ / Zr / Si ₇₀ -Zr ₁₇ -Ag ₁₃ ⁽⁷⁾ / Zr / Si ₇₀ -Zr ₁₇ -Ag ₁₃ ⁽⁸⁾ / Zr / Si ₇₀ -Zr ₁₇ -Ag ₁₃ ⁽⁹⁾ / Zr / Si ₇₀ -Zr ₁₇ -Ag ₁₃ ⁽¹⁰⁾ / Zr Example 2 Si ₅₈ -Zr ₄₂ / Si ₈₅ -Zr ₁₅ ⁽¹⁾ / Si ₅₈ -Zr ₄₂ / Si ₈₅ -Zr ₁₅ ⁽²⁾ / Si ₅₈ -Zr ₄₂ / Si ₈₅ -Zr ₁₅ ⁽³⁾ / Si ₅₈ -Zr ₄₂ / Si ₈₅ -Zr ₁₅ ⁽⁴⁾ / Si ₅₈ -Zr ₄₂ / Si ₈₅ -Zr ₁₅ ⁽⁵⁾ / Si ₅₈ -Zr ₄₂ / Si ₈₅ -Zr ₁₅ ⁽⁶⁾ / Si ₅₈ -Zr ₄₂ / Si ₈₅ -Zr ₁₅ ⁽⁷⁾ / Si ₅₈ -Zr ₄₂ / Si ₈₅ -Zr ₁₅ ⁽⁸⁾ / Si ₅₈ -Zr ₄₂ / Si ₈₅ -Zr ₁₅ ⁽⁹⁾ / Si ₅₈ -Zr ₄₂ / Si ₈₅ -Zr ₁₅ ⁽¹⁰⁾ / Si ₅₈ -Zr ₄₂ / Si ₈₅ -Zr ₁₅ ⁽¹¹⁾ / Si ₅₈ -Zr ₄₂ / Si ₈₅ -Zr ₁₅ ⁽¹²⁾ / Si ₅₈ -Zr ₄₂ / Si ₈₅ -Zr ₁₅ ⁽¹³⁾ / Si ₅₈ -Zr ₄₂ / Si ₈₅ -Zr ₁₅ ⁽¹⁴⁾ / Si ₅₈ -Zr ₄₂ Example 3 Zr / Si ₇₀ -Zr ₁₇ -Ag ₁₃ ⁽¹⁾ / Si ₅₀ -Zr ₄₁ -Ag ₉ / Si ₇₀ -Zr ₁₇ -Ag ₁₃ ⁽²⁾ / Si ₅₀ -Zr ₄₁ -Ag ₉ / Si ₇₀ -Zr _17- Ag ₁₃ ⁽³⁾ / Si ₅₀ -Zr ₄₁ -Ag ₉ / Si ₇₀ -Zr ₁₇ -Ag ₁₃ ⁽⁴⁾ / Si ₅₀ -Zr ₄₁ -Ag ₉ / Si ₇₀ -Zr ₁₇ -Ag ₁₃ ⁽⁵⁾ / Si ₅₀ -Zr ₄₁ -Ag ₉ / Si ₇₀ -Zr ₁₇ -Ag ₁₃ ⁽⁶⁾ / Si ₅₀ -Zr ₄₁ -Ag ₉ / Si ₇₀ -Zr ₁₇ -Ag ₁₃ ⁽⁷⁾ / Si ₅₀ -Zr ₄₁ -Ag ₉ / Si ₇₀ -Zr ₁₇ -Ag ₁₃ ⁽⁸⁾ / Si ₅₀ -Zr ₄₁ -Ag ₉ / Si ₇₀ -Zr ₁₇ -Ag ₁₃ ⁽⁹⁾ / Si ₅₀ -Zr ₄₁ -Ag ₉ / Si ₇₀ -Zr ₁₇ -Ag ₁₃ ^{( 10)} / Si ₅₀ -Zr ₄₁ -Ag ₉

(Experimental Example 1)

In order to measure the electrochemical characteristics of the anode thin films prepared in Examples 1 and 2, a lithium metal was used as a counter electrode and a reference electrode, and a coin cell type half cell was manufactured using the anode active materials of Examples 1 to 2. .

As an electrolyte, a mixed solution of EC / DEC (1: 1 vol%) in which 1M LiPF ₆ was dissolved was used, and a product composed of three layers of PP / PE / PP was used as a separator. The conditions for the evaluation of the electrochemical characteristics were evaluated according to the method of charging and discharging with lithium at a current density of 30 mA / cm 2 in a cut-off section of lithium from 0 to 1.2 V.

7 is a graph showing the charge and discharge capacity according to the cycle of the negative electrode prepared in Example 1, Figure 8 is a graph showing the charge and discharge capacity according to the cycle of the negative electrode prepared in Example 8.

7 and 8, it can be seen that the cathodes prepared in Examples 1 and 2 do not have a change in capacity per unit area even when charge and discharge proceed, and thus have excellent charge and discharge cycle characteristics.

(Example 4)

A cathode prepared in Example 2 on a Ni substrate; Solid electrolyte (LiPON); A positive electrode (LiCoO ₂ ) and a positive electrode current collector (Pt); were sequentially stacked to fabricate a lithium secondary thin film battery (structure of FIG. 6).

The negative electrode, solid electrolyte, positive electrode and positive electrode current collector were deposited using a sputtering method. Cathode and anode current collectors were deposited while maintaining an initial vacuum of 2.0 × 10 ⁻⁶ torr or less during deposition and then maintaining a pressure control pressure of 5 m Torr in an argon atmosphere during deposition. At this time, the solid electrolyte (LiPON) was deposited while maintaining the initial vacuum level of 1.0 X 10 ^-6 torr or less, and maintaining a pressure pressure of 10 m Torr in a nitrogen atmosphere during deposition. In addition, the anode was maintained at an initial vacuum level of 4.0 X 10 ^-6 torr or less, and during deposition, argon gas and oxygen gas were flowed at 45 and 5 sccm, respectively, and the deposition pressure was maintained at 5 m Torr.

At this time, the thickness of the negative electrode was 0.6 μm, the solid electrolyte (LiPON) was deposited to a thickness of 1.8 μm, the positive electrode (LiCoC ₂ ) to 1.3 μm, and the positive electrode current collector (Pt) to 0.3 μm.

(Experimental Example 2)

In order to measure the electrochemical characteristics of the all-solid-state thin film battery prepared in Example 4, a cut-off voltage was applied at 2.5 to 3.9 V, and the charging and discharging was performed in a constant current manner at a current density of 30 mA / cm 2. Evaluated according to.

9 is a graph showing the discharge capacity according to the cycle of the thin film battery prepared in Example 4.

9, it can be seen that the thin film battery manufactured in Example 4 has no change in capacity per unit area during discharge. This result is due to the fact that volume expansion and contraction of the cathode of the multilayer thin film structure according to the present invention is suppressed, thereby greatly improving cycle characteristics.

10 is a graph of charge and discharge of the first cycle of the thin film battery prepared in Example 4 of the present invention. Referring to Figure 10, it can be seen that the negative electrode thin film battery produced by the present invention has an operating voltage of about 3.3V.

(Example 5)

An anode current collector Pt on the PES substrate; Positive electrode (LiCoO ₂ ); Solid electrolyte (LiPON); And a negative electrode prepared in Example 2; A negative electrode current collector (Zr); was sequentially stacked to manufacture a lithium secondary thin film battery (structure of FIG. 5).

Each component was deposited under the same conditions as in Example 4, and 100 Å of Li ₄ Ti ₅ O ₁₂ was inserted between the cathode and the electrolyte, and 100 Å of TiN was inserted between the anode and the electrolyte. Heat treatment was carried out at 30 ° C. for 30 minutes.

At this time, the thickness of the negative electrode was 0.6 μm, the solid electrolyte (LiPON) was deposited to a thickness of 1.5 μm, the positive electrode (LiCoC ₂ ) to 1.3 μm, and the positive electrode current collector (Pt) to 0.3 μm.

(Experimental Example 3)

In order to measure the electrochemical characteristics of the all-solid-state thin film battery prepared in Example 5, a cut-off voltage was applied at 2.5 to 3.9 V, and the charging and discharging was performed in a constant current manner at a current density of 30 mA / cm 2. Evaluated according to.

11 is a graph showing the discharge capacity according to the cycle of the thin film battery prepared in Example 5.

Referring to FIG. 11, it can be seen that in the thin film battery manufactured in Example 5, the thin film battery manufactured in the same manner as in Example 4 has no change in capacity per unit area during discharge. These results show that the volume expansion and contraction of the cathode of the multilayer thin film structure according to the present invention is suppressed to have excellent cycle characteristics.

12 is a graph of charge and discharge of the first cycle of the thin film battery prepared in Example 5 of the present invention.

12, it can be seen that the thin film battery produced by the present invention has an operating voltage of about 3.3V.

As described above, in accordance with the present invention, by using a multilayer thin film of a silicon-based alloy which greatly improves cycle characteristics by suppressing volume expansion and contraction in place of lithium as a cathode, the chemical and mechanical stability of the electrode and electrolyte interfaces are greatly improved. Let's do it.

Claims (26)

(a) a silicon-metal active layer comprising a metal that reacts with silicon without reacting with lithium, and (b) a buffer layer located on the silicon-metal active layer Including a cathode thin film comprising a, The buffer layer is a silicon-metal layer having a low silicon concentration, The silicon-metal layer having a low silicon concentration is represented by the following Chemical Formula 2, The negative electrode thin film is a negative electrode for a lithium secondary thin film battery comprising a multilayer thin film in which the silicon-metal active layer and the buffer layer alternately stacked. [Formula 2] Si _1-y -M _y (In Formula 2, M _y is Ma or Ma-Mb, In this case, Ma is titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zirconium (Zr), niobium ( Nb), molybdenum (Mo), thallium (Ta), tungsten (W), hafnium (Hf), rhenium (Re) and one kind of metal selected from the group consisting of Mb is one metal selected from the group consisting of silver (Ag), gold (Au), aluminum (Al), zinc (Zn), tin (Sn), antimony (Sb), and combinations thereof, y is a real number between 0.4 and 1.0.) The method of claim 1, The silicon-metal active layer is a negative electrode for a lithium secondary thin film battery is represented by the following formula (1): [Formula 1] Si _1-x -M _x In Formula 1, M _x is Ma or Ma-Mb, In this case, Ma is titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zirconium (Zr), niobium ( Nb), molybdenum (Mo), thallium (Ta), tungsten (W), hafnium (Hf), rhenium (Re) and one kind of metal selected from the group consisting of Mb is one metal selected from the group consisting of silver (Ag), gold (Au), aluminum (Al), zinc (Zn), tin (Sn), antimony (Sb), and combinations thereof, x is a real number from 0.2 to 0.5. delete delete delete The method of claim 1, The silicon-metal active layer is a negative electrode for a lithium secondary thin film battery having a thickness of 50 to 5000 kPa. The method of claim 1, The buffer layer is a negative electrode for a lithium secondary thin film battery having a thickness of 10 to 500 kPa. The method of claim 1, The negative electrode is a negative electrode for a lithium secondary thin film battery having a thickness of 0.1 ㎛ to 3 ㎛. The method of claim 1, The uppermost layer of the negative electrode is a negative electrode for a lithium secondary thin film battery consisting of the buffer layer. (i) forming a buffer layer on the substrate, and (ii) forming a silicon-metal active layer on the buffer layer Including, The buffer layer is a silicon-metal layer having a low silicon concentration, The silicon-metal layer having a low silicon concentration is represented by the following Chemical Formula 2, The forming of the silicon-metal active layer may be performed at least once or more. [Formula 2] Si _1-y -M _y (In Formula 2, M _y is Ma or Ma-Mb, In this case, Ma is titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zirconium (Zr), niobium ( Nb), molybdenum (Mo), thallium (Ta), tungsten (W), hafnium (Hf), rhenium (Re) and one kind of metal selected from the group consisting of Mb is one metal selected from the group consisting of silver (Ag), gold (Au), aluminum (Al), zinc (Zn), tin (Sn), antimony (Sb), and combinations thereof, y is a real number between 0.4 and 1.0.) The method of claim 10, The silicon-metal active layer is a method of manufacturing a negative electrode for a lithium secondary thin film battery is represented by the following formula (1): [Formula 1] Si _1-x -M _x In Formula 1, M _x is Ma or Ma-Mb, In this case, Ma is titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zirconium (Zr), niobium ( Nb), molybdenum (Mo), thallium (Ta), tungsten (W), hafnium (Hf), rhenium (Re) and one kind of metal selected from the group consisting of Mb is one metal selected from the group consisting of silver (Ag), gold (Au), aluminum (Al), zinc (Zn), tin (Sn), antimony (Sb), and combinations thereof, x is a real number from 0.2 to 0.5. delete delete delete The method of claim 10, The silicon-metal active layer and the silicon-metal layer having low silicon concentration perform one method selected from the group consisting of magnetron sputtering, DC diode sputtering, electron beam vapor deposition, and ion beam sputtering. Method for producing a negative electrode for a lithium secondary thin film battery that is formed by. The method of claim 10, After forming the buffer layer, Performing any one of a process of applying a direct current bias to the multilayer thin film, a process of heating a substrate, an ion beam irradiation process, and a plasma treatment process A negative electrode manufacturing method for a lithium secondary thin film battery further comprising. Electrically insulating substrates; Anode current collector; anode; Solid electrolytes; The negative electrode of claim 1; Cathode current collector; And a lithium secondary thin film battery in which protective films are sequentially stacked. Electrically conductive substrates or anode current collectors; anode; Solid electrolytes; The negative electrode of claim 1; Cathode current collector; And a lithium secondary thin film battery in which protective films are sequentially stacked. Electrically insulating substrates; Cathode current collector; The negative electrode of claim 1; Solid electrolytes; anode; Anode current collector; And a lithium secondary thin film battery in which protective films are sequentially stacked. Electrically conductive substrates or cathode current collectors; The negative electrode of claim 1; Solid electrolytes; anode; Anode current collector; And a lithium secondary thin film battery in which protective films are sequentially stacked. The method according to any one of claims 17 to 20, The anode is LiCoO ₂ , LiMn ₂ O ₄ , LiNiO ₂ , LiCo _{1- x} Ni _x O ₂ (0.2 <x <0.8), LiM _y Mn _{2 - y} O ₄ (where M is Cr, Ni, Co, Al, Fe, Cu, Mg and one selected from the group consisting of a combination of 0.2 <y <1.8, Li ₂ MMn ₃ O ₈ (wherein M is Co or Fe), LiFePO ₄ , LiVOPO ₄ and mixtures thereof Lithium secondary thin film battery containing one material selected from the group consisting of. The method according to any one of claims 17 to 20, The solid electrolyte may include at least one inorganic electrolyte selected from the group consisting of lithium phosphorous oxynitride (LiPON), lithium silicon phosphorous oxynitride (LiSiPON), lithium silicon oxynitride (LiSiON), lithium boron phosphorous oxynitride (LiBPON), and combinations thereof; or Polyethylene derivatives, polyethylene oxide derivatives, polypropylene oxide derivatives, phosphate ester polymers, polyitation lysine, polyester sulfides, polyvinyl alcohols, polyvinylidene fluorides, polymers including ionic dissociating groups and combinations thereof One polymer electrolyte selected from the group consisting of Lithium secondary thin film battery comprising one electrolyte selected from the group consisting of. The method according to any one of claims 17 to 20, And a diffusion barrier layer between the negative electrode and the solid electrolyte or between the positive electrode and the solid electrolyte. 24. The method of claim 23, The diffusion barrier layer is selected from the group consisting of Au, Ag, Pt, Pd, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zr, Nb, Mo, Ta, W, Hf, Re, and combinations thereof At least one metal or alloy; Nitrides including one selected from the group consisting of Ti, Cr, HF, Mo , Nb, V, Ta, Zr, and combinations thereof; RuO ₂ ; Li ₂ RuO ₃ ; And a lithium secondary thin film battery comprising one selected from the group consisting of a combination thereof. The method according to any one of claims 17 to 20, Lithium secondary thin film battery further comprises a lithium composite metal compound layer between the negative electrode and the solid electrolyte. 26. The method of claim 25, The lithium composite metal compound layer is Li _{3 - x} M _x N (wherein M is one selected from the group consisting of Co, Cu, Ni and combinations thereof, 0≤x≤0.5), Li ₄ Ti ₅ O ₁₂ And A lithium secondary thin film battery comprising one selected from the group consisting of a combination thereof.

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