Top cover structure of full-tab battery

Abstract

The invention provides a full-tab battery top cover structure which comprises a core package, two connecting pieces, an aluminum shell and an upper cover, and a positive tab and a negative tab are arranged on the two opposite short sides of the core package respectively; each connecting piece comprises a first part and a second part which are mutually connected and integrally formed, the included angle between the first part and the second part is 90 degrees, the first part extends outwards to form a boss and is inwards attached to the longer part of the core package in an insulating manner, and the second part is connected with the tab; the aluminum shell wraps the outer side of the core bag, an opening is formed in the long face of the core bag, and the aluminum shell abuts against the two short sides of the core bag in an insulating mode. The upper cover is buckled with the opening of the aluminum shell, the upper cover is provided with two through holes, the two connecting sheets are clamped between the upper cover and the core package, and bosses on the two connecting sheets penetrate out of the through holes. The problem of space waste caused by large top tab reservation and structural member occupation is effectively solved, the internal space of the battery is fully utilized, and the cell performance and the energy density are improved.

Description

Technical Field

[0001] The present invention relates to the field of new energy technology, and in particular to a novel battery top cover structure with full pole ears. Background Art

[0002] In recent years, with the reduction of lithium battery manufacturing costs and raw material costs and the gradual improvement of battery cycle life, lithium batteries are now widely used in automobiles and energy storage fields. Whether it is a power battery or an energy storage battery, increasing capacity within the same volume is an important research direction with obvious economic value.

[0003] There are two main directions to improve the volume energy density of battery cells, namely increasing the unit gram capacity of raw materials and improving the utilization of the internal space of the battery cells. Considering safety and battery cell expansion during charging and discharging, the front and back and left and right spaces inside the battery cells have been fully utilized, but there is a huge remaining space on the top of the battery cells. Usually, a space of 10-13mm is reserved during design to place structural parts and tabs. How to reasonably reduce the top space has become an important research aspect to improve the utilization of battery cell space.

[0004] There are two main reasons for the waste of space at the top of the battery cell;

[0005] 1: In traditional connecting piece welding, after the tab is welded to the connecting piece, it needs to be folded 90°. Bending will also occupy the internal height space of the battery cell and there is a risk of internal short circuit caused by the tab being inserted.

[0006] 2: In the prior art, the connection method between the lithium / sodium battery tab and the top cover pole is mainly to weld the tab to the adapter, and then weld the adapter to the pole. In this process, the adapter occupies the battery space, and the cost is high while increasing the internal resistance of the battery cell.

[0007] Therefore, how to effectively solve the problem of space waste caused by the large and structural parts reserved for the top tab, make full use of the internal space of the battery, and improve the performance and energy density of the battery cell is an issue that the industry urgently needs to solve. Summary of the invention

[0008] A main purpose of the present invention is to overcome at least one defect of the above-mentioned prior art and to provide a full-tab battery top cover structure that can effectively solve the problem of space waste caused by the large top tab reservation and the occupation of structural parts, make full use of the internal space of the battery, and improve the performance and energy density of the battery cell.

[0009] In order to achieve the above-mentioned invention object, the present invention adopts the following technical scheme:

[0010] According to one aspect of the present invention, a full-tab battery top cover structure is provided, comprising:

[0011] A core package, wherein the positive electrode tab and the negative electrode tab are respectively disposed on two relatively shorter sides of the core package;

[0012] Two connecting pieces, each of which includes a first part and a second part that are connected to each other and formed as one piece, the angle between the first part and the second part is 90 degrees, the first part has a boss extending outwardly, and is insulated and abutted against a longer part of the core package inwardly, and the second part is connected to the positive electrode tab and the negative electrode tab respectively;

[0013] An aluminum shell, which is wrapped around the outside of the core package and has an opening on a longer side of the core package, and the aluminum shell is insulated and abutted against two shorter sides of the core package;

[0014] An upper cover is buckled with the opening of the aluminum shell, the upper cover is provided with two through holes, two connecting pieces are clamped between the upper cover and the core package, and the bosses on the two connecting pieces pass through the through holes.

[0015] According to one embodiment of the present invention, the positive electrode tab and the negative electrode tab are both full tabs.

[0016] According to one embodiment of the present invention, the connecting sheet is provided with a slot, and the positive electrode tab and the negative electrode tab both pass through the slot and are welded to the connecting sheet.

[0017] According to an embodiment of the present invention, a retaining bracket is disposed on the inner side of the upper cover, and the retaining bracket is located between the upper cover and the connecting piece.

[0018] According to an embodiment of the present invention, an elastic insulating member is provided between the first portion and the core package.

[0019] According to an embodiment of the present invention, an insulating gasket is provided between the boss and the through hole, the boss is respectively two poles, and a pole insulating sheet is attached to the outer surface of the boss.

[0020] According to one embodiment of the present invention, an explosion-proof valve is provided between the two through holes.

[0021] According to one embodiment of the present invention, a protective film is attached to the explosion-proof valve.

[0022] According to an embodiment of the present invention, the upper cover is provided with a liquid injection hole.

[0023] According to one embodiment of the present invention, a transparent insulating film is wrapped outside the core package.

[0024] It can be seen from the above technical solution that the advantages and positive effects of the full-tab battery top cover structure of the present invention are:

[0025] In the present invention, the angle between the first part and the second part is 90 degrees, and the first part has a boss extending outward, which is insulated and abutted against the longer part of the core package inward, effectively solving the problem of space waste caused by the large space reserved for the top tab and the occupation of structural parts, making full use of the internal space of the battery, and improving the performance and energy density of the battery cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the top cover structure and core pack assembly of the full-tab battery of the present invention.

[0027] Figure 2 It is a schematic diagram of the structural components of the top cover of the full-tab battery of the present invention.

[0028] Figure 3 It is a schematic diagram of a partially enlarged structure of the full-tab battery top cover structure after assembly of the present invention.

[0029] Figure 4 It is a schematic diagram of the assembly process of the components of the full-tab battery top cover structure of the present invention.

[0030] Description of the figure number:

[0031] 1- Aluminum shell;

[0032] 2- core package;

[0033] 3- Elastic insulating member;

[0034] 4-first connecting piece; 41-first boss;

[0035] 5-second connecting piece; 51-second boss; 52-opening;

[0036] 6-first insulating gasket;

[0037] 7- second insulating gasket;

[0038] 8-Holding bracket;

[0039] 9-upper cover; 91-liquid injection hole; 92-first pole insulating gasket; 93-second pole insulating gasket; 94-explosion-proof valve; 95-protective film;

[0040] 100-transparent insulating film; DETAILED DESCRIPTION

[0041] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that the present invention will be comprehensive and complete and fully convey the concepts of the example embodiments to those skilled in the art. The same reference numerals in the figures represent the same or similar structures, and thus their detailed description will be omitted.

[0042] In the following description of different examples of the present invention, reference is made to the accompanying drawings, which form a part of the present invention and in which different exemplary structures, systems and steps that can implement multiple aspects of the present invention are shown by way of example. It should be understood that other specific schemes of components, structures, exemplary devices, systems and steps can be used, and structural and functional modifications can be made without departing from the scope of the present invention. Moreover, although the terms "top", "bottom", "front", "rear", "side", etc. may be used in this specification to describe different exemplary features and elements of the present invention, these terms are used herein only for convenience, such as according to the direction of the examples described in the accompanying drawings. Nothing in this specification should be construed as requiring a specific three-dimensional orientation of the structure to fall within the scope of the present invention.

[0043] In order to make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the technical scheme in the embodiments of the present invention will be described clearly and completely below. If the specific conditions are not specified in the embodiments, they are carried out according to conventional conditions or conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments used is not specified, they are all conventional products that can be purchased commercially.

[0044] Figure 1 It is a schematic diagram of the top cover structure and core pack assembly of the full-tab battery of the present invention.

[0045] Figure 2 It is a schematic diagram of the structural components of the top cover of the full-tab battery of the present invention.

[0046] Figure 3 It is a schematic diagram of a partially enlarged structure of the full-tab battery top cover structure after assembly of the present invention.

[0047] Figure 4 It is a schematic diagram of the assembly process of the components of the full-tab battery top cover structure of the present invention.

[0048] like Figures 1 to 4 As shown, the present invention provides a full-tab battery top cover structure, comprising:

[0049] A core package 2, wherein two relatively shorter sides of the core package 2 are respectively provided with a positive electrode tab and a negative electrode tab;

[0050] A first connecting sheet 4 and a second connecting sheet 5, each of the first connecting sheet 4 and the second connecting sheet 5 comprises a first portion and a second portion which are connected to each other and formed integrally, the angle between the first portion and the second portion is 90 degrees, a first boss 41 extends outward from the first portion of the first connecting sheet 4, a second boss 51 extends outward from the first portion of the second connecting sheet, the first portion is insulated and abuts against a longer portion of the core package 2, and the second portion is connected to the positive electrode tab and the negative electrode tab respectively;

[0051] An aluminum shell 1, wherein the aluminum shell 1 is wrapped around the outside of the core package 2 and is opened on a longer side of the core package 2, and the aluminum shell 1 is insulated and abutted against two shorter sides of the core package 2;

[0052] The upper cover 9 is buckled with the opening of the aluminum shell 1, and the upper cover 9 is provided with two through holes. The first connecting piece 4 and the second connecting piece 5 are clamped between the upper cover 9 and the core package 2. The boss 41 on the first connecting piece 4 and the boss 51 on the second connecting piece 5 pass through the through holes to form a first pole and a second pole respectively.

[0053] According to one embodiment of the present invention, the positive electrode tab and the negative electrode tab are both full tabs.

[0054] According to one embodiment of the present invention, the first connecting sheet 4 and the second connecting sheet 5 are both provided with slots, and the positive electrode tab and the negative electrode tab both pass through the slots and are welded to the first connecting sheet 4 and the second connecting sheet 5. Since the materials are the same, laser welding between them is simple and quick, and welding fracture and explosion welding due to different melting points of different metals will not occur.

[0055] According to one embodiment of the present invention, a retaining bracket 8 is disposed inside the upper cover 9 , and the retaining bracket 8 is located between the upper cover 9 and the first connecting piece 4 and the second connecting piece 5 .

[0056] According to one embodiment of the present invention, an elastic insulating member 3 is disposed between the first portion and the core package 2 .

[0057] According to one embodiment of the present invention, a first insulating gasket 6 and a second insulating gasket 7 are respectively arranged between the first boss 41, the second boss 51 and the through hole, the first boss 41 and the second boss 51 are respectively the first pole and the second pole, and the first pole insulating sheet 92 and the second pole insulating sheet 93 are respectively attached to the outer surfaces of the first boss 41 and the second boss 51.

[0058] According to one embodiment of the present invention, an explosion-proof valve 94 is disposed between the two through holes.

[0059] According to one embodiment of the present invention, a protective film 95 is attached to the explosion-proof valve 94 .

[0060] According to one embodiment of the present invention, the upper cover 9 is provided with a liquid injection hole 91 .

[0061] According to one embodiment of the present invention, a transparent insulating film 100 is wrapped around the outside of the core package.

[0062] In some embodiments, the first boss 41 and the second boss 51 are separate terminal structures, and a welding platform between the first boss 41 and the second boss 51 and the connecting piece needs to be reserved below the top cover structure, which increases the process and reduces the overall battery cell assembly space.

[0063] In some embodiments, the bracket 8 and the connecting piece 5 below the injection hole 91 are not provided with guide grooves or holes, which affects the penetration efficiency of the electrolyte and reduces the production efficiency.

[0064] In some embodiments, no elastic insulating sheet 3 is added between the core package 2 and the first connecting sheet 4 and the second connecting sheet 5. During assembly, metal may easily scratch the diaphragm and cause a short circuit. During charging and discharging, large overcurrent may cause the metal to heat and melt the diaphragm, resulting in a short circuit.

[0065] In some embodiments, the first insulating gasket 6 and the second insulating gasket 7 are not designed as an embedded structure, and cannot perfectly utilize the surplus space below the retaining bracket 8, thereby increasing the thickness of the overall structure by 0.5-1 mm and reducing the overall battery cell assembly space.

[0066] In some embodiments, the first connecting piece 4 and the second connecting piece 5 are not L-shaped structures and need to be welded on the top of the battery cell. A 7-9 mm tab extension space must be reserved on the top to avoid tab tearing, which greatly reduces the overall battery cell assembly space and reduces the overall energy density.

[0067] In some embodiments, the first pole insulating gasket 92 and the second pole insulating gasket 93 are not designed as embedded structures. In order to achieve a good sealing effect, they need to be placed between the top cover 9 and the retaining bracket 8 for sealing, which increases the overall structure thickness by 1-1.5 mm and reduces the overall battery cell assembly space.

[0068] In some embodiments, the explosion-proof valve protective film 95 is not designed with embossing. If a safety problem such as an internal short circuit occurs, the explosion-proof valve cannot release pressure according to the set safety threshold and safe injection direction, increasing safety hazards.

[0069] It can be seen from the above technical solution that the advantages and positive effects of the full-tab lithium battery of the present invention are:

[0070] In the present invention, the angle between the first part and the second part is 90 degrees, and the first part has a boss extending outward, which is insulated and abutted against the longer part of the core package inward, effectively solving the problem of space waste caused by the large space reserved for the top tab and the occupation of structural parts, making full use of the internal space of the battery, and improving the performance and energy density of the battery cell.

[0071] Take the manufacturing process of square aluminum shell battery as an example, Figure 4 The specific steps are as follows:

[0072] 1. The square aluminum shell battery in this embodiment includes a shell 1, a battery core pack 2, a first connecting plate 4, a second connecting plate 5, and other structural parts.

[0073] 2. The shell 1 has an opening and accommodates the battery core pack. The top cover assembly includes a top cover plate 9, a liquid injection hole 91, a first insulating gasket 92, a second insulating gasket 93, an explosion-proof valve 94, and a protective film 95.

[0074] 3. The upper cover plate retaining bracket 8 is provided with mounting holes on the left and right sides to facilitate the passage of the poles. The two sides are hollowed out to facilitate the penetration of the electrolyte downwards. Reinforcing ribs are provided at the bottom to enhance the overall structure.

[0075] 4. The first connecting piece 4 and the second connecting piece 5 comprise a first pole 41 and a second pole 51. An opening 52 is provided on the top of the second connecting piece 5 to facilitate the penetration of the electrolyte.

[0076] 6. Put the first connecting piece 4, the second connecting piece 5, the first sealing ring 6, the second sealing ring 7, the upper cover plate holding bracket 8, the upper cover plate 9, the first pole insulating gasket 92, the second pole insulating gasket 93 of the above structure, press Figure 4 Assemble in sequence.

[0077] 7. The assembled structure is assembled and welded to the battery cell 2.

[0078] 8. After assembly and welding, use a transparent insulating film 100 for packaging.

[0079] 9. The packaged whole structure is placed into a shell, and the aluminum shell 1 and the upper cover plate 9 are sealed by laser welding.

[0080] 10. Assembly is complete.

[0081] The prior art has many structural parts, which makes assembly complicated and wastes space. The present invention makes the following substantial improvements to the top cover:

[0082] 1. The connecting piece is made into a boss, the upper cover is made into a through hole, and the pole is integrated

[0083] 2. The traditional top cover design is optimized, retaining only the insulating pad, top cover, retaining bracket, and sealing gasket, which are sealed through structural coordination, thus optimizing the waste of top space and improving the utilization rate of the internal space of the battery.

[0084] The structure and technical effects of the present invention also include the following:

[0085] 1. The present invention comprises an upper insulating pad, a top cover, a retaining bracket, a sealing gasket, a connecting piece, and an elastic insulating member.

[0086] 2. The boss structure is designed at the junction of the connecting piece and the top cover to be inserted into the cover plate pole. The cover plate pole hole is a through hole. The integrated pole can effectively reduce the space waste of structural parts and reduce the internal resistance of the battery.

[0087] 3. A sealing gasket is designed between the connecting piece boss and the retaining bracket. The sealing gasket is an upper embedded structure, which ensures the sealing effect while making full use of the hollow space below the retaining bracket.

[0088] 4. The insulating gasket above the cover adopts a bottom-embedded design, which ensures insulation while improving the sealing of the battery.

[0089] Although the embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and cannot be understood as limiting the present invention. A person of ordinary skill in the art may change, modify, replace and modify the above embodiments within the scope of the present invention. A person of ordinary skill in the technical field to which the present invention belongs shall understand that the specific structures and process steps shown in the above specific implementation methods are merely exemplary and non-restrictive. Moreover, a person of ordinary skill in the technical field to which the present invention belongs may combine the various technical features shown above in various possible ways to form a new technical solution, or make other changes, all of which are within the scope of the present invention.

Claims

1. A full-tab battery top cover structure, characterized in that: include: A core package, wherein the positive electrode tab and the negative electrode tab are respectively disposed on two relatively shorter sides of the core package; Two connecting pieces, each of which includes a first part and a second part that are connected to each other and formed as one piece, the angle between the first part and the second part is 90 degrees, the first part has a boss extending outwardly, and is insulated and abutted against a longer part of the core package inwardly, and the second part is connected to the positive electrode tab and the negative electrode tab respectively; An aluminum shell, which is wrapped around the outside of the core package and has an opening on a longer side of the core package, and the aluminum shell is insulated and abutted against two shorter sides of the core package; An upper cover is buckled with the opening of the aluminum shell, the upper cover is provided with two through holes, two connecting pieces are clamped between the upper cover and the core package, and the bosses on the two connecting pieces pass through the through holes.

2. The full-tab battery top cover structure according to claim 1, characterized in that: The positive electrode tab and the negative electrode tab are both full tabs.

3. The full-tab battery top cover structure according to claim 2, characterized in that: The connecting sheet is provided with a slot, and the positive electrode tab and the negative electrode tab both pass through the slot and are welded to the connecting sheet.

4. The full-tab battery top cover structure according to claim 1, characterized in that: A retaining bracket is arranged on the inner side of the upper cover, and the retaining bracket is located between the upper cover and the connecting piece.

5. The full-tab battery top cover structure according to claim 4, characterized in that: An elastic insulating member is arranged between the first portion and the core package.

6. The full-tab battery top cover structure according to claim 1, characterized in that: An insulating gasket is arranged between the boss and the through hole, the boss is respectively two poles, and a pole insulating sheet is attached to the outer surface of the boss.

7. The full-tab battery top cover structure according to claim 6, characterized in that: An explosion-proof valve is arranged between the two through holes.

8. The full-tab battery top cover structure according to claim 7, characterized in that: A protective film is attached to the explosion-proof valve.

9. The full-tab battery top cover structure according to claim 1, characterized in that: The upper cover is provided with a liquid injection hole.

10. The full-tab battery top cover structure according to claim 1, characterized in that: The core package is wrapped with a transparent insulating film on the outside.

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