CN217903362U

CN217903362U - Secondary battery assembly and secondary battery

Info

Publication number: CN217903362U
Application number: CN202221279321.6U
Authority: CN
Inventors: 胡鹏; 喻先锋; 王兴东; 蔡云龙; 刘婵; 侯敏; 曹辉
Original assignee: Shanghai Ruipu Energy Co Ltd
Current assignee: Shanghai Ruipu Energy Co Ltd; Rept Battero Energy Co Ltd
Priority date: 2022-05-25
Filing date: 2022-05-25
Publication date: 2022-11-25
Anticipated expiration: 2032-05-25

Abstract

The application relates to a secondary battery assembly and a secondary battery, including: the battery core assembly comprises at least two battery cores arranged side by side, and tabs extend out of the battery cores; the adapter conductor is provided with a lug assembling hole; the insulating base plate is positioned between the electric core assembly and the adapter conductor, and is provided with a tab through hole; and the lug of the battery cell sequentially penetrates through the lug through hole and the lug assembling hole and then is welded and connected with the switching conductor. The secondary battery assembly of this application passes insulating backing plate and switching conductor through utmost point ear and rubs to flatten and spread welded fastening connection on the switching conductor, can solidify the form of utmost point ear completely, and every layer utmost point ear is unanimous to the route of switching conductor welding department, the lax state is the same, and utmost point ear can not be redundant, sink, and utmost point ear does not have the risk of inserting in the pole piece, and secondary battery does not have the short circuit risk. Through solidifying the shape of the tab, the tab is not extruded, thereby improving the performance of the battery and prolonging the service life of the battery.

Description

Secondary battery assembly and secondary battery

Technical Field

The present invention relates to the field of secondary battery technology, and more particularly, to a secondary battery module and a secondary battery.

Background

At present, secondary battery usually includes top cap, casing, electric core, switching piece, and the inside assembly structure of battery usually includes two kinds, and first assembly structure adopts welded connection with the switching piece with one or more utmost point ear setting in the below of switching piece, connects the switching piece of electric core utmost point ear again with the utmost point post welded connection of top cap. The second kind of assembly structure is to set up one or more utmost point ear in the below of utmost point post directly with top cap utmost point post welded connection, after realizing the connection of utmost point ear and utmost point post, through buckling utmost point ear, accomplish secondary battery's structural assembly with electric core packing casing.

The two assembling structures have various problems respectively, the first assembling structure is that the lug is positioned below the adapter plate, the lug folding space is reduced, meanwhile, the paths from each layer of lug to the welding position of the adapter plate are inconsistent, the loosening states are different, the problems of lug redundancy, lug sinking and the like can be caused, the lug is in contact with the pole piece, and the short circuit safety risk of the battery is increased. Meanwhile, the tab of the connection mode is longer, so that the internal resistance of the battery is increased, the performance of the battery is influenced, and the capacity density of the battery is also influenced. On the other hand, the tabs are extruded, the tabs on the outer side are stressed, the tabs are easy to damage and break, overcurrent capacity is reduced, and performance and service life of the battery are affected.

The second assembly structure is that the tabs are positioned below the poles, and although the switching piece is cancelled, the problems of inconsistent paths and different loosening states of the welding part of each layer of tabs to the switching piece still exist, the tabs are not supported by the switching piece, the problems of tab redundancy, tab sinking and the like are easily caused, the tabs are easily inserted into the pole pieces, and the safety risk of short circuit of the battery is increased. Meanwhile, the assembly structure is only suitable for the secondary battery with smaller thickness and size and has larger limitation. The secondary battery with larger thickness dimension has longer length of the electrode lug of the battery core, the redundancy and sinking problems of the electrode lug are more serious, the performance of the battery is influenced, and the short circuit safety risk of the battery is higher.

Disclosure of Invention

The embodiment of the application provides a secondary battery assembly and a secondary battery, which are used for solving the problems of long lug length and high safety risk of a secondary battery connecting structure in the related art.

A first aspect of embodiments of the present application provides a secondary battery assembly including:

the battery cell assembly comprises at least two battery cells arranged side by side, and tabs extend out of the battery cells;

the switching conductor is provided with a lug assembling hole;

after being folded, the lugs of the battery cell sequentially penetrate through the lug through holes and the lug assembling holes upwards and then are connected with the switching conductor in a welding mode;

or the lugs of the battery cells outside the battery assembly upwards sequentially penetrate through the lug through holes and the two sides of the switching conductor after being collected, and are connected with the switching conductor in a welding mode, and the lugs of the other battery cells upwards sequentially penetrate through the lug through holes and the lug assembling holes after being collected, and are connected with the switching conductor in a welding mode.

In some embodiments: the projection of the lug assembling hole and the projection of the lug penetrating through the lug assembling hole in the height direction are overlapped.

In some embodiments: the lug sequentially penetrates through the lug through hole and the lug assembling hole and then is welded and connected with the hole wall of the switching conductor;

or the lug sequentially penetrates through the lug through hole and the lug assembly hole and then is connected with the top surface of the switching conductor in a welding mode through bending.

In some embodiments: the battery core assembly comprises at least three battery cells arranged side by side, and tabs of the battery cells positioned at the outermost side penetrate through the tab through holes and are then welded and connected with the side walls of the adapter conductors;

or the lug of the battery cell positioned at the outermost side passes through the lug through hole and then is wound to the upper part of the adapter conductor from the side part of the adapter conductor to be connected with the top surface of the adapter conductor in a welding mode.

In some embodiments: the number of the battery cores is n, n is a positive integer larger than or equal to 3, and the number of the lug assembly holes formed in the switching conductor is n-2.

In some embodiments: the battery core assembly comprises at least three battery cores arranged side by side, the height of the pole lug of the battery core positioned at the outermost side is larger than that of the pole lug of the battery core positioned at the inner side, and the pole lug of each battery core is bent towards the direction of the battery core positioned at the innermost side and is in welded connection with the pole lug of the battery core positioned at the innermost side.

In some embodiments: the tabs comprise positive tabs and negative tabs which are arranged on the battery cell at intervals;

the switching conductor includes anodal switching piece and negative pole switching piece, utmost point ear pilot hole is including being located anodal pilot hole on the switching piece of anodal to and be located the negative pole pilot hole on the switching piece of negative pole.

In some embodiments: and chamfers or fillets are arranged around the orifices of the lug assembling holes, positioning grooves matched with the profiles of the switching conductors are formed in the tops of the insulating base plates, and the switching conductors are positioned in the positioning grooves.

A second aspect of embodiments of the present application provides a secondary battery including:

the casing, the casing is open-top and encloses hollow structure all around, be equipped with above-mentioned any embodiment in the casing secondary battery subassembly, the top of casing is equipped with the top cap that seals secondary battery subassembly in the casing, be equipped with the utmost point post of being connected with the switching conductor on the top cap.

A third aspect of the embodiments of the present application provides a method of assembling a secondary battery using the above-described secondary battery, including the steps of:

laminating and ultrasonically pre-welding a plurality of layers of pole pieces led out of the battery core into a pole lug;

bundling a plurality of battery cores side by side, and bundling and combining the plurality of battery cores into a battery core assembly;

arranging an insulating base plate at the top of the electric core assembly, wherein the pole lugs of each electric core penetrate through the pole lug through holes of the insulating base plate;

arranging a switching conductor on the top of the insulating base plate, wherein the pole lugs of each battery cell penetrate through the pole lug assembly holes of the switching conductor;

bending the pole lugs penetrating through the pole lug assembling holes, and attaching and welding the pole lugs to the top surfaces of the switching conductors to form a secondary battery assembly;

a top cover connected with the switching conductor is arranged at the top of the secondary battery component, and a pole of the top cover is electrically connected with the switching conductor;

the secondary battery assembly is put into a case having an open top, and the secondary battery assembly is enclosed in the case by a top cover.

The beneficial effect that technical scheme that this application provided brought includes:

the embodiment of the application provides a secondary battery assembly and a secondary battery, because the secondary battery assembly is provided with an electric core assembly, the electric core assembly comprises at least two electric cores arranged side by side, and lugs extend out of the electric cores; the adapter conductor is provided with a lug assembling hole; the insulating base plate is positioned between the electric core assembly and the adapter conductor, and is provided with a tab through hole; after being folded, the lugs of the battery cell sequentially penetrate through the lug through holes and the lug assembling holes upwards and then are connected with the switching conductor in a welding mode; or the lugs of the battery cells outside the battery assembly upwards sequentially penetrate through the lug through holes and the two sides of the switching conductor after being folded and then are connected with the switching conductor in a welding mode, and the lugs of the other battery cells upwards sequentially penetrate through the lug through holes and the lug assembling holes after being folded and then are connected with the switching conductor in a welding mode.

Therefore, the secondary battery assembly of the application can completely solidify the form of the tab by collecting the tab, penetrating the insulating base plate and the switching conductor to rub and flatten and spread the tab on the switching conductor for welding and fixing connection, the path from each layer of tab to the welding position of the switching conductor is consistent, the relaxation state is the same, the tab cannot be redundant and sink, the tab does not have the risk of being inserted into a pole piece, and the secondary battery does not have the safety risk of short circuit. Through the solidification utmost point ear form, make utmost point ear can not extruded, utmost point ear atress, utmost point ear can not damage and fracture to promote the performance and the increase of service life of battery. The insulating backing plate acts on between electric core subassembly and the switching conductor, when solidification utmost point ear form, makes the insulation protection and prevents the short circuit, can also provide the location for the switching conductor.

The secondary battery of this application has reduced the height between top cap to the electric core through solidification utmost point ear form, has promoted the height of electric core, very big promotion secondary battery's volume energy density. And through solidifying the lug shape, the lug height of the battery cell is shortened, the internal resistance of the secondary battery is reduced, and the voltage platform and the performance of the secondary battery are improved. The secondary battery's assembly structure application of this application is extensive, is applicable to two cores, four cores, six cores or even eight core structures, and secondary battery thickness size is big more, and electric core is more, and secondary battery volume energy density is high more. The secondary battery assembly structure is simple, and the manufacturing cost of the secondary battery is reduced.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 is a schematic structural view of a battery pack according to an embodiment of the present application;

fig. 2 is a schematic structural diagram of a battery cell according to an embodiment of the present application;

fig. 3 is a schematic structural diagram of a four-cell battery assembly according to an embodiment of the present application;

fig. 4 is a schematic structural view of a four-cell battery pack according to an embodiment of the present invention before electrode welding;

fig. 5 is a schematic view illustrating a structure of a four-cell battery module according to an embodiment of the present invention after welding electrodes;

fig. 6 is an exploded view of the structure of a four-cell battery pack according to an embodiment of the present application;

fig. 7 is a schematic structural view of a two-cell battery assembly according to an embodiment of the present application;

fig. 8 is a schematic view of a structure of a two-cell battery pack according to an embodiment of the present invention before electrode welding;

fig. 9 is a schematic view showing a structure of a two-cell battery module according to an embodiment of the present invention after electrode welding;

fig. 10 is an exploded view of the structure of a two-cell battery pack according to an embodiment of the present application;

fig. 11 is a schematic structural view of a six-cell battery pack according to an embodiment of the present application;

fig. 12 is a schematic structural view of a six-cell battery pack according to an embodiment of the present application before electrode welding;

fig. 13 is a schematic view of a six-cell battery pack according to an embodiment of the present invention after electrode welding;

fig. 14 is an exploded view of the structure of a six-cell battery pack according to an embodiment of the present application;

fig. 15 is a schematic structural view of an eight-cell battery assembly according to an embodiment of the present application;

fig. 16 is a schematic structural view of an eight-cell battery pack according to an embodiment of the present application before electrode welding;

fig. 17 is a schematic view of an electrode welded structure of an eight-cell battery pack according to an embodiment of the present application;

fig. 18 is an exploded view of the structure of an eight-cell battery pack according to an embodiment of the present application;

fig. 19 is a schematic structural view of a battery assembly with different tab heights according to an embodiment of the present disclosure;

fig. 20 is a schematic structural view of a battery assembly with different tab heights before electrode welding according to an embodiment of the present application;

fig. 21 is a schematic structural view of a battery assembly with different tab heights after electrode welding according to an embodiment of the present application;

fig. 22 is an exploded view of the structure of a battery pack with different tab heights according to an embodiment of the present invention;

fig. 23 is a schematic structural diagram of a distance between a transit conductor and a cell according to an embodiment of the present application;

fig. 24 is a schematic structural view of a secondary battery according to an embodiment of the present application;

fig. 25 is an exploded view of the structure of a secondary battery according to an embodiment of the present application.

Reference numerals are as follows:

1. a secondary battery; 11. a top cover; 111. a top cover plate; 112. a lower insulating member;

12. a positive electrode patch; 12a to 12f are first to twelfth positive electrode mounting holes, respectively;

13. a negative pole switching piece; 13a to 13f are first to twelfth negative electrode mounting holes, respectively;

14. an insulating base plate; 14a to 14d are respectively a first tab through hole to a fourth tab through hole;

15. an electric core; 151 to 158 are first to eighth cells, respectively;

151a to 158a are first to eighth positive electrode tabs, respectively, and 151b to 158b are first to eighth negative electrode tabs, respectively;

16. a housing;

s1 to S16 are the first to sixteenth welding portions, respectively.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

The embodiment of the application provides a secondary battery assembly and a secondary battery, which can solve the problems of long lug length and high safety risk of a secondary battery connecting structure in the related art.

Referring to fig. 1 and 2, a first aspect of an embodiment of the present application provides a secondary battery assembly including:

the battery cell assembly comprises at least two battery cells 15 arranged side by side, and the battery cells 15 extend to form electrode lugs which comprise anode electrode lugs and cathode electrode lugs positioned on two sides of the top of the battery cells 15. The battery cell 15 is made by winding or laminating, and includes a positive electrode sheet, a negative electrode sheet, and a separator for separating the positive electrode sheet and the negative electrode sheet. The positive and negative electrode tabs each include a coated portion coated with an active material and an uncoated portion not coated with an active material, and may have polarities different from each other due to the difference in the materials of the active materials coated thereon. The uncoated part of the positive plate forms a positive electrode tab, the uncoated part of the negative plate forms a negative electrode tab, and the positive electrode tab and the negative electrode tab respectively extend out of the top of the battery core 15.

The adapter conductor is provided with a tab assembling hole for penetrating the tab. The switching conductor comprises a positive electrode switching sheet 12 and a negative electrode switching sheet 13, wherein the positive electrode switching sheet 12 is a copper sheet, and the negative electrode switching sheet 13 is a copper sheet or an aluminum sheet. The tab assembly holes comprise positive electrode assembly holes located on the positive electrode adapter sheet 12 and negative electrode assembly holes located on the negative electrode adapter sheet 13, the positive electrode assembly holes are located above the positive electrode tabs, and the negative electrode assembly holes are located above the negative electrode tabs. The projection of the positive pole assembling hole and the positive pole lug penetrating through the positive pole assembling hole in the height direction is superposed to shorten the length of the positive pole lug; the negative pole pilot hole coincides with the projection of the negative pole utmost point ear in the direction of height that passes this negative pole pilot hole to shorten the length of negative pole utmost point ear. The number of the positive electrode assembly holes and the negative electrode assembly holes is specifically set according to the number of the cells 15 of the cell assembly. For example, if the number of the battery cells 15 is n, the number of the positive electrode assembly holes and the number of the negative electrode assembly holes may be n-2, for example, if the number of the battery cells 15 is six, the number of the positive electrode assembly holes and the number of the negative electrode assembly holes are four.

And the insulating base plate 14 is positioned between the core assembly and the positive adapter plate 12 and the negative adapter plate 13 of the adapter conductor, and the insulating base plate 14 is provided with a tab through hole for penetrating a tab. The insulating pad 14 is disposed above the battery cell 15 and below the positive electrode adaptor sheet 12 and the negative electrode adaptor sheet 13, and the positive electrode adaptor sheet 12 and the negative electrode adaptor sheet 13 are separated from the battery cell 15 by the insulating pad 14. The number of the tab through holes of the insulating base plate 14 is at least four, and the four tab through holes are respectively located at four corners of the insulating base plate 14 and used for respectively penetrating the tabs of the battery cells 15. Due to the presence of the insulating spacer 14, when the top cover 11 is assembled with the housing 16, even under the pressing action of the assembly force, the positive electrode adaptor piece 12 and the negative electrode adaptor piece 13 do not contact the battery cell 15, and an internal short circuit is not caused by the contact, thereby improving the safety of the secondary battery 1.

After the positive electrode tab and the negative electrode tab of the battery cell 15 are folded and upwards sequentially pass through the tab through holes of the insulating base plate 14, the positive electrode tab penetrates into the positive electrode assembly hole of the positive electrode adapter sheet 12 to be welded with the positive electrode adapter sheet 12, and the negative electrode tab penetrates into the negative electrode assembly hole of the negative electrode adapter sheet 13 to be welded with the negative electrode adapter sheet 12. Or after being folded, the positive electrode tab and the negative electrode tab of the battery pack outer side battery cell 15 sequentially penetrate through the tab through hole and the two sides of the positive electrode adapter sheet 12 and the negative electrode adapter sheet 13 upwards and are then welded with the positive electrode adapter sheet 12 and the negative electrode adapter sheet 13; after the positive electrode tabs and the negative electrode tabs of the rest of the battery cells 15 upwards sequentially pass through the tab through holes after being folded, the positive electrode tabs penetrate into the positive electrode assembly holes of the positive electrode adapter pieces 12 to be welded with the positive electrode adapter pieces 12, and the negative electrode tabs penetrate into the negative electrode assembly holes of the negative electrode adapter pieces 13 to be welded with the negative electrode adapter pieces 12.

The positive assembly hole of the positive adapter plate 12 is positioned right above the positive pole lug, so that the distance between the positive pole lug and the positive adapter plate 12 is shortest; the negative pole assembly hole of the negative pole adapter plate 13 is positioned right above the negative pole tab, so that the distance between the negative pole tab and the negative pole adapter plate 13 is shortest. The positive pole adapter plate 12 and the negative pole adapter plate 13 can respectively and effectively support a positive pole lug and a negative pole lug, so that the positive pole lug and the negative pole lug are kept in a good fixed form, the paths from each layer of lugs to the welding position of the adapter conductor are consistent, the loosening state is the same, redundancy and sinking are avoided, and no short circuit risk exists.

The secondary battery assembly of the embodiment of the application can completely solidify the shape of the tab by collecting the tab, penetrating through the insulating base plate 14 and the switching conductor, rubbing, flattening and paving the tab on the switching conductor for welding and fixing connection, the path from each layer of tab to the welding position of the switching conductor is consistent, the relaxation state is the same, the tab cannot be redundant and sink, the tab does not have the risk of being inserted into a pole piece, and the secondary battery does not have the safety risk of short circuit. Through the solidification utmost point ear form, make utmost point ear can not extruded, utmost point ear atress, utmost point ear can not damage and fracture to promote the performance and the increase of service life of battery. The insulating backing plate 14 acts on the electrode core assembly and the adapter conductor, and when the electrode lug shape is solidified, the insulating backing plate can perform insulating protection to prevent short circuit and can also provide positioning for the adapter conductor.

In some alternative embodiments: referring to fig. 3 to 6, an embodiment of the present application provides a secondary battery assembly employing a four-cell battery assembly, which includes a first cell 151, a second cell 152, a third cell 153, and a fourth cell 154 arranged side by side. A first positive electrode tab 151a and a first negative electrode tab 151b are respectively disposed on two sides of the top of the first cell 151. A second positive electrode tab 152a and a second negative electrode tab 152b are respectively disposed on two sides of the top of the second cell 152. A third positive electrode tab 153a and a third negative electrode tab 153b are respectively arranged on two sides of the top of the third cell 153. A fourth positive electrode tab 154a and a fourth negative electrode tab 154b are respectively disposed on two sides of the top of the fourth cell 154.

The switching conductor comprises a positive electrode switching sheet 12 and a negative electrode switching sheet 13, wherein the positive electrode switching sheet 12 is a copper sheet, and the negative electrode switching sheet 13 is a copper sheet or an aluminum sheet. The positive electrode adaptor piece 12 is provided with a first positive electrode assembly hole 12a for inserting the second positive electrode tab 152a and a second positive electrode assembly hole 12b for inserting the third positive electrode tab 153 a. The negative adapter plate 13 is provided with a second negative assembling hole 13b for penetrating the second negative tab 152b and a first negative assembling hole 13a for penetrating the third negative tab 153b. The positive electrode transition piece 12 is not provided with a positive electrode assembly hole for penetrating the first positive electrode tab 151a and the fourth positive electrode tab 154a, and the first positive electrode tab 151a and the fourth positive electrode tab 154a are both positioned on the outer side of the positive electrode transition piece 12, so that the material is saved and the processing cost is reduced. The negative pole adapter sheet 13 is not provided with a negative pole assembling hole for penetrating the first negative pole lug 151b and the fourth positive pole lug 154b, and the first negative pole lug 151b and the fourth positive pole lug 154b are both positioned at the outer side of the negative pole adapter sheet 13, so that the material is saved and the processing cost is reduced.

An insulating pad 14, the insulating pad 14 is located between the positive pole transition piece 12 and the negative pole transition piece 13 of the core assembly and the transition conductor, a first tab through hole 14a penetrating the first positive pole tab 151a and the second positive pole tab 152a is opened on the insulating pad 14, a second tab through hole 14b penetrating the third positive pole tab 153a and the fourth positive pole tab 154a, a third tab through hole 14c penetrating the third negative pole tab 153b and the fourth negative pole tab 154b, and a fourth tab through hole 14d penetrating the first negative pole tab 151b and the second negative pole tab 152b. The insulating pad 14 is disposed above the battery cell 15 and below the positive electrode adaptor sheet 12 and the negative electrode adaptor sheet 13, and the positive electrode adaptor sheet 12 and the negative electrode adaptor sheet 13 are separated from the battery cell 15 by the insulating pad 14.

The first positive electrode tab 151a passes through the first tab through hole 14a and then winds from the side of the positive electrode tab 12 to the upper side of the positive electrode tab 12, and the first positive electrode tab 151a is bent and then welded to the top surface of the positive electrode tab 12 to form a first welding portion S1. The second positive electrode tab 152a sequentially passes through the first tab through hole 14a and the first positive assembly hole 12a from bottom to top, and the top surfaces of the positive electrode adapter pieces 12 are welded and connected to form a second welding portion S1 after the second positive electrode tab 152a is bent. The third positive electrode tab 153a sequentially passes through the second tab through hole 14b and the second positive electrode assembly hole 12b from bottom to top, and is bent and then welded to the top surface of the positive electrode adaptor plate 12 to form a third welding portion S3. The fourth positive electrode tab 154a passes through the second tab through hole 14b and then winds from the side of the positive electrode tab 12 to the upper side of the positive electrode tab 12, and the fourth positive electrode tab 154a is bent and then welded to the top surface of the positive electrode tab 12 to form a fourth welding portion S4.

The first negative electrode tab 151b passes through the fourth tab through hole 14d, and then winds from the side of the negative electrode tab 13 to the upper side of the negative electrode tab 13, and the first negative electrode tab 151b is bent and then welded to the top surface of the negative electrode tab 13 to form a fifth welded portion S5. The second negative electrode tab 152b sequentially passes through the fourth tab through hole 14d and the second negative electrode assembly hole 13b from bottom to top, and the second negative electrode tab 152b is bent and then welded to the top surface of the negative electrode adaptor plate 13 to form a sixth welding portion S6. The third negative electrode tab 153b sequentially passes through the third tab through hole 14c and the first negative electrode assembly hole 13a from bottom to top, and the third negative electrode tab 153b is bent and then welded to the top surface of the negative electrode adapter sheet 13 to form a seventh welding portion S7. The fourth negative electrode tab 154b passes through the third tab through hole 14c and then winds from the side of the negative electrode adaptor piece 13 to the upper side of the negative electrode adaptor piece 13, and the fourth negative electrode tab 154b is bent and then welded to the top surface of the negative electrode adaptor piece 13 to form an eighth welding portion S8.

Of course, after the positive electrode tabs and the negative electrode tabs of the second battery cell 152 and the third battery cell 153 sequentially pass through the tab through holes and the tab assembly holes, the positive electrode tabs and the negative electrode tabs can be directly and respectively welded to the hole walls of the tab assembly holes of the positive electrode adapter plate 12 and the negative electrode adapter plate 13. After the positive electrode tabs and the negative electrode tabs of the first battery cell 151 and the fourth battery cell 154 penetrate through the tab through holes, the positive electrode tabs and the negative electrode tabs can be directly and respectively welded to the side walls of the positive electrode adaptor sheet 12 and the negative electrode adaptor sheet 13.

In some alternative embodiments: referring to fig. 7 to 10, an embodiment of the present application provides a secondary battery assembly using a two-cell battery assembly, which includes a first cell 151 and a second cell 152 arranged side by side. A first positive electrode tab 151a and a first negative electrode tab 151b are respectively disposed on two sides of the top of the first cell 151. A second positive electrode tab 152a and a second negative electrode tab 152b are respectively disposed on two sides of the top of the second cell 152. The switching conductor comprises a positive electrode switching piece 12 and a negative electrode switching piece 13, wherein the positive electrode switching piece 12 is a copper sheet, and the negative electrode switching piece 13 is a copper sheet or an aluminum sheet. In order to reduce the material cost and the processing cost, the positive pole adapter plate 12 and the negative pole adapter plate 13 are not required to be provided with pole lug assembling holes for penetrating pole lugs. The positive electrode tab 12 is disposed between the first positive electrode tab 151a and the second positive electrode tab 152a, and the negative electrode tab 13 is disposed between the first negative electrode tab 151b and the second negative electrode tab 152b.

The first positive electrode tab 151a passes through the first tab through hole 14a and then winds from the side of the positive electrode tab 12 to the upper side of the positive electrode tab 12, and the first positive electrode tab 151a is bent and then welded to the top surface of the positive electrode tab 12 to form a first welding portion S1. The second positive electrode tab 152a passes through the second tab through hole 14b and then winds from the side of the positive electrode adaptor sheet 12 to the upper side of the positive electrode adaptor sheet 12, and the second positive electrode tab 152a is bent and then welded to the top surface of the positive electrode adaptor sheet 12 to form a second welding portion S2. The first negative electrode tab 151b passes through the fourth tab through hole 14d, and then winds from the side of the negative electrode tab 13 to the upper side of the negative electrode tab 13, and the first negative electrode tab 151b is bent and then welded to the top surface of the negative electrode tab 12 to form a third welding portion S3. The second negative electrode tab 152b passes through the third tab through hole 14c and then winds from the side of the negative electrode adaptor piece 13 to the upper side of the negative electrode adaptor piece 13, and the second negative electrode tab 152b is bent and then welded to the top surface of the negative electrode adaptor piece 13 to form a fourth welding portion S4.

In some alternative embodiments: referring to fig. 11 to 14, an embodiment of the present application provides a secondary battery assembly using a six-cell battery assembly having an addition of a fifth cell 155 and a sixth cell 156, as compared to a four-cell battery assembly. A fifth positive electrode tab 155a and a fifth negative electrode tab 155b are respectively disposed on two sides of the top of the fifth cell 155. A sixth positive electrode tab 156a and a sixth negative electrode tab 156b are respectively disposed on two sides of the top of the sixth cell 156. Correspondingly, a third positive electrode assembly hole 12c and a fourth positive electrode assembly hole 12d are added on the positive electrode adapter sheet 12 used by the six-core battery pack, and a third negative electrode assembly hole 13c and a fourth negative electrode assembly hole 13d are added on the negative electrode adapter sheet 13 used by the six-core battery pack.

The mounting modes of the first to sixth positive electrode tabs, the first to sixth negative electrode tabs of the six-core battery assembly and the positive electrode adapter sheet 12 and the negative electrode adapter sheet 13 are the same as the mounting modes of the first to fourth positive electrode tabs, the first to fourth negative electrode tabs of the four-core battery assembly and the positive electrode adapter sheet 12 and the negative electrode adapter sheet 13, and specific mounting and connecting modes are not repeated. The first to sixth positive electrode tabs of the six-core battery assembly according to the embodiment of the present application are welded to the positive electrode tab 12, and a first welding portion S1, a second welding portion S2, a third welding portion S3, a fourth welding portion S4, a fifth welding portion S5, and a sixth welding portion S6 are sequentially formed. The first to sixth negative electrode tabs are welded to the negative electrode adaptor sheet 13, and a seventh welding portion S7, an eighth welding portion S8, a ninth welding portion S9, a tenth welding portion S10, an eleventh welding portion S11, and a twelfth welding portion S12 are formed in this order.

In some alternative embodiments: referring to fig. 15 to 18, an embodiment of the present application provides a secondary battery assembly using an eight-core battery assembly in which a seventh battery cell 157 and an eighth battery cell 158 are added as compared to a six-core battery assembly. And a seventh positive electrode tab 157a and a seventh negative electrode tab 157b are respectively arranged on two sides of the top of the seventh battery cell 157. An eighth positive electrode tab 158a and an eighth negative electrode tab 158b are respectively disposed on two sides of the top of the eighth cell 158. The positive pole adapter sheet 12 used by the corresponding eight-core battery assembly is additionally provided with a fifth positive pole assembling hole 12e and a sixth positive pole assembling hole 12f, and the negative pole adapter sheet 13 used by the eight-core battery assembly is additionally provided with a fifth negative pole assembling hole 13e and a sixth negative pole assembling hole 13f.

The mounting modes of the first to eighth positive electrode tabs, the first to eighth negative electrode tabs of the eight-core battery assembly and the positive electrode adapter sheet 12 and the negative electrode adapter sheet 13 are the same as the mounting modes of the first to sixth positive electrode tabs, the first to sixth negative electrode tabs of the six-core battery assembly and the positive electrode adapter sheet 12 and the negative electrode adapter sheet 13, and specific mounting and connecting modes are not repeated. First to eighth positive electrode tabs of the eight-element battery assembly according to the embodiment of the present application are welded to the positive electrode tab 12, and a first welding portion S1, a second welding portion S2, a third welding portion S3, a fourth welding portion S4, a fifth welding portion S5, a sixth welding portion S6, a seventh welding portion S7, and an eighth welding portion S8 are sequentially formed. The first to eighth negative electrode tabs are welded to the negative electrode adaptor sheet 13, and a ninth welding portion S9, a tenth welding portion S10, an eleventh welding portion S11, a twelfth welding portion S12, a thirteenth welding portion S13, a fourteenth welding portion S14, a fifteenth welding portion S15, and a sixteenth welding portion S16 are formed in this order.

In some alternative embodiments: referring to fig. 19 to 22, the present embodiment provides a secondary battery assembly using a four-cell battery assembly having different tab heights, which is different from the four-cell battery assembly of the above embodiment in that: in the embodiment of the present application, the heights of the first positive electrode tab 151a, the first negative electrode tab 151b, the fourth positive electrode tab 154a, and the fourth negative electrode tab 154b of the first cell 151 and the fourth cell 154 of the four-cell battery assembly having different tab heights are the same. The heights of the second positive electrode tab 152a, the second negative electrode tab 152b, the third positive electrode tab 153a and the third negative electrode tab 153b of the second cell 152 and the third cell 153 are the same. And the heights of the first positive electrode tab 151a, the first negative electrode tab 151b, the fourth positive electrode tab 154a and the fourth negative electrode tab 154b are all higher than the heights of the second positive electrode tab 152a, the second negative electrode tab 152b, the third positive electrode tab 153a and the third negative electrode tab 153b.

After the second positive electrode tab 152a and the third positive electrode tab 153a pass through the tab assembly holes of the positive electrode adaptor sheet 12, the second positive electrode tab 152a and the third positive electrode tab 153a are bent towards the central axis direction of the positive electrode adaptor sheet 12 and are welded to the top surface of the positive electrode adaptor sheet 12. After the second negative electrode tab 152b and the third positive electrode tab 153a penetrate through the tab assembly holes of the negative electrode adaptor piece 13, the second negative electrode tab 152b and the third positive electrode tab 153a are bent towards the central axis direction of the negative electrode adaptor piece 13 and are welded to the top surface of the negative electrode adaptor piece 13.

The first positive electrode tab 151a and the fourth positive electrode tab 154a penetrate through the tab assembly holes of the positive electrode adapter sheet 12 and then bend towards the direction of the second positive electrode tab 152a and the direction of the third positive electrode tab 153a, the first positive electrode tab 151a and the second positive electrode tab 152a are welded to form a first welding portion S1, and the fourth positive electrode tab 154a and the third positive electrode tab 153a are welded to form a second welding portion S2. The first negative electrode tab 151b and the fourth negative electrode tab 154b penetrate through tab assembly holes of the negative electrode adapter sheet 13 and then bend towards the second negative electrode tab 152b and the third positive electrode tab 153a, the first negative electrode tab 151b and the second negative electrode tab 152b are welded to form a third welding portion S3, and the fourth negative electrode tab 154b and the third negative electrode tab 153b are welded to form a fourth welding portion S4.

In some alternative embodiments: referring to fig. 3 to 6, embodiments of the present invention provide a secondary battery assembly, in which a chamfer or fillet is formed around an orifice of a tab assembly hole, and the chamfer or fillet is beneficial to supporting a tab and does not tear the tab due to burrs and sharp corners. The top of the insulating base plate 14 is respectively provided with a positioning groove matched with the outlines of the positive adapter plate 12 and the negative adapter plate 13, and the positive adapter plate 12 and the negative adapter plate 13 are respectively positioned in the positioning grooves to provide mounting and fixing positions for the positive adapter plate 12 and the negative adapter plate 13.

Referring to fig. 23 to 25, a second aspect of the embodiment of the present application provides a secondary battery, the secondary battery 1 including:

a housing 16 having a hollow structure with a top opening and a periphery closed, the secondary battery module according to any of the above embodiments being mounted in the housing 16, a top cover 11 for closing the secondary battery module in the housing 16 being provided on the top of the housing 16, and a pole connected to the switching conductor being provided on the top cover 11 for leading the current of the secondary battery module out of the housing 16. The top cap 11 includes a top cap plate 111 and a lower insulating member 112 positioned at the bottom of the top cap plate 111, and the assembly of the secondary battery 1 is completed after the transfer conductor of the secondary battery pack, which is mounted in the case 16, is connected to the post on the top cap 11. The tab of the secondary battery 1 of this assembly structure is completely fixed in the space formed by the adaptor conductor and the insulating spacer 14; meanwhile, the height H1 of the battery cell from the top cover plate 111 to the battery cell is = T1 (the thickness of the lower insulating part 112) + T2 (the thickness of the switching conductor) + T3 (the thickness of the insulating base plate 14), so that the height of the battery cell is increased, and the volume energy density of the secondary battery is greatly increased.

Referring to fig. 24 and 25, a third aspect of the embodiment of the present application provides a secondary battery assembling method using the above-described secondary battery 1, the secondary battery 1 assembling method including the steps of:

step 101, laminating multiple layers of pole pieces led out from the battery cell 15, and then ultrasonically pre-welding the pole pieces to form pole lugs, wherein the pole lugs comprise a positive pole lug and a negative pole lug.

102, bundling a plurality of battery cores 15 side by side, and bundling and combining the plurality of battery cores 15 into a battery core assembly.

Step 103, arranging an insulating base plate 14 on the top of the battery cell assembly, and enabling the positive electrode tab and the negative electrode tab of each battery cell 15 to penetrate through the tab through holes of the insulating base plate 14.

Step 104, arranging a switching conductor on the top of the insulating base plate 14, wherein the positive pole lug and the negative pole lug of each battery cell 15 penetrate through the lug assembly holes of the switching conductor, and the switching conductor comprises a positive pole switching piece 12 and a negative pole switching piece 13.

And 105, bending the positive electrode tab and the negative electrode tab which penetrate through the tab assembling holes, and respectively attaching and welding the positive electrode tab and the negative electrode tab to the top surfaces of the positive electrode adapter plate 12 and the negative electrode adapter plate 13 to form a secondary battery assembly.

And 106, arranging a top cover 11 connected with the anode adapter sheet 12 and the cathode adapter sheet 13 on the top of the secondary battery assembly, wherein a pole of the top cover 11 is electrically connected with the adapter conductor, the pole comprises an anode pole and a cathode pole, and the anode pole and the cathode pole are respectively connected with the anode adapter sheet 12 and the cathode adapter sheet 13.

Step 107, the secondary battery assembly is loaded into the case 16 with the top opened, and the secondary battery assembly is enclosed in the case 16 by the top cover 11.

According to the secondary battery assembling method, the height requirement on the tab is greatly reduced, the raw material cost is reduced, and the rolling and stretching effects can be effectively improved after the tab is shortened (due to the fact that poor stretching of a hollow foil area can cause burrs to be generated on the die-cut tab, and safety risks exist). After the tabs are shortened, the volume energy density of the battery core is improved, the space utilization rate of the secondary battery is improved, and the problem of a section caused by pressing the positive tabs and the negative plates when the tabs are bent is solved.

In the description of the present application, it should be noted that the terms "upper", "lower", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, which are only for convenience in describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and operate, and thus, should not be construed as limiting the present application. Unless expressly stated or limited otherwise, the terms "mounted," "connected," and "connected" are intended to be inclusive and mean, for example, that they may be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.

It is noted that, in the present application, relational terms such as "first" and "second", and the like, are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrases "comprising a," "8230," "8230," or "comprising" does not exclude the presence of additional like elements in a process, method, article, or apparatus that comprises the element.

The above description is merely exemplary of the present application and is presented to enable those skilled in the art to understand and practice the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A secondary battery assembly, comprising:

the battery pack comprises a battery core assembly, wherein the battery core assembly comprises at least two battery cores (15) arranged side by side, and tabs extend out of the battery cores (15);

the adapter conductor is provided with a lug assembling hole;

the insulation backing plate (14) is positioned between the electric core assembly and the adapter conductor, and a tab through hole is formed in the insulation backing plate (14);

the lug of the battery cell (15) penetrates through the lug through hole and the lug assembling hole upwards in sequence after being folded and then is connected with the switching conductor in a welding mode;

or the lugs of the battery pack outer side battery cells (15) are welded with the switching conductor after upwards sequentially penetrating through the lug through holes and the two sides of the switching conductor after being folded, and the lugs of the other battery cells (15) are welded with the switching conductor after upwards sequentially penetrating through the lug through holes and the lug assembly holes after being folded.

2. A secondary battery assembly according to claim 1, wherein:

the projection of the lug assembling hole and the projection of the lug penetrating through the lug assembling hole in the height direction are overlapped.

3. A secondary battery assembly according to claim 1, wherein:

the lug sequentially penetrates through the lug through hole and the lug assembling hole and then is welded and connected with the hole wall of the switching conductor;

or the lug sequentially penetrates through the lug through hole and the lug assembling hole and then is connected with the top surface of the switching conductor in a welding mode after being bent.

4. A secondary battery assembly as claimed in claim 1, wherein:

the battery core assembly comprises at least three battery cores (15) arranged side by side, and a tab positioned on the outermost battery core (15) penetrates through the tab through hole and then is welded and connected with the side wall of the switching conductor;

or the pole lug of the battery cell (15) positioned at the outermost side passes through the pole lug through hole and then is wound to the upper part of the adapter conductor from the side part of the adapter conductor to be connected with the top surface of the adapter conductor in a welding way.

5. A secondary battery assembly as claimed in claim 1, wherein:

the number of the battery cores (15) is n, n is a positive integer larger than or equal to 3, and the number of the lug assembly holes formed in the switching conductor is n-2.

6. A secondary battery assembly as claimed in claim 1, wherein:

the battery pack assembly comprises at least three battery cores (15) arranged side by side, the height of a lug positioned on the outermost battery core (15) is larger than that of a lug positioned on the inner battery core (15), and the lug of each battery core (15) is bent towards the direction of the innermost battery core (15) and is in welded connection with the lug of the innermost battery core (15).

7. A secondary battery assembly according to claim 1, wherein:

the lugs comprise positive lugs and negative lugs which are arranged on the battery cell (15) at intervals;

the switching conductor includes anodal switching piece (12) and negative pole switching piece (13), utmost point ear pilot hole is including being located anodal pilot hole on switching piece (12) to and being located the negative pole pilot hole on negative pole switching piece (13).

8. A secondary battery assembly as claimed in claim 1, wherein:

and chamfers or fillets are arranged around the orifices of the lug assembling holes, positioning grooves matched with the profiles of the switching conductors are formed in the tops of the insulating base plates (14), and the switching conductors are positioned in the positioning grooves.

9. A secondary battery, characterized by comprising:

the secondary battery assembly comprises a shell (16), wherein the shell (16) is of a hollow structure with an open top and a closed periphery, the secondary battery assembly of any one of claims 1 to 8 is arranged in the shell (16), a top cover (11) for sealing the secondary battery assembly in the shell (16) is arranged at the top of the shell (16), and a pole connected with a switching conductor is arranged on the top cover (11).