Battery cell internal parallel type square battery top cover and battery structure

Abstract

The utility model discloses a battery core internal parallel type square battery top cover and a battery structure, relates to the technical field of power batteries, and provides the following scheme aiming at the problems that the process difficulty is increased, the yield is reduced and the battery charging and discharging are unbalanced due to external parallel connection after the capacity of an existing battery core monomer is too large. The battery comprises a top cover assembly, a cover plate in the top cover assembly is integrally formed, positive pole columns are arranged at the two ends of the cover plate, positive pole column concave parts are arranged at the positions, opposite to the positive pole columns, of the bottom of the cover plate, a positive switching piece is welded to one side of each positive pole column concave part, only a negative pole column is arranged in the middle of the cover plate, and a negative pole column concave part is arranged on the other side of each negative pole column. And a negative electrode adapter sheet is welded on the outer side of the concave part of the negative electrode post. According to the utility model, the battery core internal parallel structure is adopted, the yield is improved, and when the large-capacity battery monomer integrated module is designed, the number of the battery monomers connected in parallel can be reduced, so that the complexity of a management system and the system design and maintenance cost are reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of power batteries, in particular to a battery core inner parallel type square battery top cover and a battery structure. Background Art

[0002] Driven by the dual-carbon economy, the development of emerging industries such as domestic new energy vehicles and energy storage power stations is extremely rapid, driving the explosive development of the lithium battery industry. Energy storage lithium batteries have become an extremely important link in the electric vehicle and wind, solar and storage industry chain, and have a huge driving effect on the development of upstream and downstream industries.

[0003] In the prior art, in order to meet the requirements of low cost and easy management in applications such as long driving range of electric vehicles and large-scale power storage in energy storage power stations, one of the measures is to make the capacity of the single battery very large, so as to reduce the weight of auxiliary components such as the shell cover plate, thereby increasing the energy density of the single battery, and then reducing the number of single batteries to be connected in series and parallel when the storage capacity is certain, thereby achieving the purpose of reducing the complexity of the management system and the application cost; if the capacity of the battery cell is too large, the process difficulty of battery cell production, winding, lamination, etc. will increase, the yield rate will decrease, and the safety of the battery will deteriorate, making it difficult to pass safety tests such as short circuit, overcharging, and needle puncture, and the battery application risk is relatively large.

[0004] In the prior art, in order to meet the requirements of long-range electric vehicles and large-scale power storage in energy storage power stations, the second measure is to connect many battery cells in parallel externally to increase the storage capacity of the battery module; connecting many battery cells in parallel externally requires a complex management system, which will increase the cost of system design and maintenance; secondly, due to the differences in capacity, internal resistance, etc. of each single battery, external parallel connection will lead to imbalance in battery charging and discharging. Utility Model Content

[0005] The utility model proposes a square battery top cover and battery structure for internally parallel cells, which solves the problem in the prior art that when the capacity of the battery cell single body is too large, the process difficulty of battery cell production, winding, lamination, etc. will increase, the yield rate will decrease, the safety of the battery will deteriorate, it will be difficult to pass the safety tests such as short circuit, overcharge, needle puncture, etc., and the application risk of the battery will be relatively large; at the same time, connecting many battery cells in parallel externally, firstly, requires a complex management system, which will increase the system design and maintenance costs; secondly, due to the differences in the capacity, internal resistance, etc. of each single battery, the external parallel connection will lead to the problem of unbalanced battery charging and discharging.

[0006] In order to achieve the above-mentioned purpose, the utility model adopts the following technical scheme: a top cover of a square battery with an inner parallel core, comprising: a top cover assembly, the top cover assembly is composed of a cover plate, an explosion-proof valve, an explosion-proof valve protective film, a positive pole, a negative pole, an insulating sealing plastic part, and an insulating plastic part, the cover plate is integrally formed, and circular or polygonal protrusions are provided at both ends of the top of the cover plate during molding, the protrusions are positive poles, and a positive pole concave part is provided at the bottom of the cover plate opposite to the positive pole, and the positive pole concave part is used for laser welding with a positive adapter;

[0007] The negative pole is located in the middle of the cover plate, and the negative pole is insulated and sealed with the cover plate by an insulating sealing plastic part; a negative pole recess is provided on the other side of the negative pole, and the negative pole recess is used for laser welding with the negative pole adapter.

[0008] Preferably, the cover plate is provided with a liquid injection hole and an exhaust hole; an explosion-proof valve is disposed below the exhaust hole, and the explosion-proof valve protection film is fixed to the upper part of the exhaust hole to prevent sharp objects from piercing the explosion-proof valve and causing failure of the explosion-proof valve.

[0009] Preferably, when the top cover assembly is assembled to the battery housing, when the gas pressure in the battery rises to reach the upper explosion pressure limit of the explosion-proof valve, the explosion-proof valve explodes, thereby achieving pressure relief inside the battery.

[0010] Preferably, the insulating plastic part is arranged at the bottom of the cover plate, and is used for insulation between the battery cells and the negative electrode adapter plate after internal connection, the cover plate, and the battery casing.

[0011] Preferably, the cover plate, the positive electrode column and the negative electrode column may be made of a variety of metal materials.

[0012] A square battery structure with inner cells connected in parallel, comprising a battery shell, a battery cell, a positive electrode adapter, a negative electrode adapter and a battery top cover, wherein the battery cell is installed inside the battery shell, and a positive electrode tab and a negative electrode tab are provided at the upper end of the battery cell, the positive electrode tab is connected to the positive electrode adapter, and the negative electrode tab is connected to the negative electrode adapter, and the upper end of the battery shell is encapsulated by a cover plate.

[0013] Preferably, the positive electrode adapter plate and the negative electrode adapter plate may be made of a variety of metal materials.

[0014] Preferably, the battery cell is a square battery cell with winding or stacked structures and tabs on the same side.

[0015] The beneficial effects of the utility model are:

[0016] 1. The utility model adopts a structure of internally parallel battery cells. The capacity of the internally parallel battery cells is not large (<200AH), the difficulty of the process of battery cell production, battery cell winding or stacking is reduced, and the yield rate is improved. In addition, if a short circuit occurs in an internally parallel battery cell, the short-circuit current is small and the heat generation is small. The battery can smoothly pass the safety tests such as short circuit, overcharge, and needle puncture. The application risk of the battery is reduced, and the problems of excessive single cell capacity, increased difficulty in the preparation process, reduced yield rate and poor safety are solved.

[0017] 2. The utility model is different from the previous method of simply increasing the capacity of single battery cells. The utility model realizes the preparation of large-capacity battery cells by connecting small-capacity (<200AH) battery cells in parallel. When using the large-capacity battery cell integrated module designed in this way, the number of parallel-connected battery cells can be reduced, thereby reducing the complexity of the management system and the system design and maintenance costs.

[0018] 3. The utility model adopts a structure of multiple battery cells connected in parallel. The internally connected battery cells are in the same electrolyte system, and there is no difference in capacity and internal resistance. This can effectively solve the problem of unbalanced battery charging and discharging caused by external parallel connection of batteries. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the battery housing structure of the present utility model.

[0020] Figure 2 It is a cross-sectional view of the top cover assembly of the utility model.

[0021] Figure 3 It is a schematic diagram of the structure of the top cover assembly of the utility model.

[0022] Figure 4 It is a schematic diagram of the exhaust hole structure of the top cover assembly of the utility model.

[0023] Figure 5 It is a schematic diagram of the negative pole structure of the utility model.

[0024] Figure 6 It is a schematic diagram of the positive pole structure of the utility model.

[0025] Figure 7 This is a schematic diagram of the battery cell structure of the utility model.

[0026] Figure 8 It is a schematic diagram of the structure of a two-cell parallel adapter and a four-cell parallel adapter of the utility model.

[0027] Fig. 9 It is a schematic diagram of the structure of a two-cell parallel adapter and a four-cell parallel adapter of the utility model.

[0028] Fig.10It is a schematic diagram of the assembly of the two battery cells in parallel structure of the utility model.

[0029] Fig.11 It is a schematic diagram of the assembly of the four-cell parallel structure of the utility model.

[0030] Fig.12 The positive and negative electrode adapters of the utility model include a structural schematic diagram.

[0031] Numbers in the figure:

[0032] 1. Battery housing;

[0033] 2. Top cover assembly; 21. Cover plate; 22. Liquid injection hole; 23. Exhaust hole; 24. Explosion-proof valve; 25. Explosion-proof valve protection film; 26. Positive pole; 261. Positive pole recess; 27. Negative pole; 271. Negative pole recess; 28. Insulating sealing plastic part; 29. ​​Insulating plastic part;

[0034] 3. Battery cell; 31. Positive electrode tab; 32. Negative electrode tab;

[0035] 4. Positive electrode adapter;

[0036] 5. Negative electrode adapter. DETAILED DESCRIPTION

[0037] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0038] Reference Figure 1-Figure 12 The utility model provides a top cover of a square battery in parallel with a cell, comprising: a top cover assembly 2, the top cover assembly 2 is composed of a cover plate 21, an explosion-proof valve 24, an explosion-proof valve protection film 25, a positive pole 26, a negative pole 27, an insulating sealing plastic part 28, and an insulating plastic part 29. The cover plate 21 is integrally formed. During the forming process, circular or polygonal protrusions are arranged at both ends of the top of the cover plate 21, and the protrusions are the positive poles 26. A positive pole concave part 261 is arranged at the bottom of the cover plate 21 opposite to the positive pole 26, and the positive pole concave part 261 is used for laser welding with the positive electrode adapter 4; the negative pole 27 is located in the middle of the cover plate 21, and the negative pole 27 is insulated and sealed with the cover plate 21 by the insulating sealing plastic part 28; a negative pole concave part 271 is arranged on the other side of the negative pole 27, and the negative pole concave part 271 is used for laser welding with the negative electrode adapter 5.

[0039] Furthermore, if Figure 3 , Figure 4 , Figure 5 , Figure 6As shown, the cover plate 21 is provided with a liquid injection hole 22 and an exhaust hole 23; an explosion-proof valve 24 is placed below the exhaust hole 23, and an explosion-proof valve protection film 25 is fixed to the upper part of the exhaust hole 23 to prevent sharp objects from piercing the explosion-proof valve 24 and causing the explosion-proof valve 24 to fail. When the top cover assembly 2 is assembled to the battery housing 1, the air pressure in the battery increases to reach the upper limit of the explosion pressure of the explosion-proof valve 24, and the explosion-proof valve 24 explodes, thereby achieving internal pressure relief of the battery to prevent the battery from exploding due to excessive pressure in the battery housing 1. An insulating plastic part 29 is arranged at the bottom of the cover plate 21, and is used for insulation between each battery cell 3 and the negative electrode adapter 5 after internal connection and the cover plate 21 and the battery housing 1.

[0040] Furthermore, the cover plate 21, the positive electrode column 26, and the negative electrode column 27 can be made of various materials, such as aluminum, aluminum alloy, copper, copper alloy, iron, stainless steel, nickel, or copper-plated nickel and other metal materials.

[0041] like Figure 1 , Figure 2 , Figure 7 As shown, a square battery structure with inner cells connected in parallel includes a battery shell 1, a battery cell 3, a positive electrode adapter plate 4, a negative electrode adapter plate 5 and a battery top cover. The battery cell 3 is installed inside the battery shell 1, and a positive electrode tab 31 and a negative electrode tab 32 are provided at the upper end of the battery cell 3. The positive electrode tab 31 is connected to the positive electrode adapter plate 4, and the negative electrode tab 32 is connected to the negative electrode adapter plate 5. The upper end of the battery shell 1 is encapsulated by a cover plate 21.

[0042] Furthermore, the positive electrode adapter plate 4 and the negative electrode adapter plate 5 can be made of various materials, such as aluminum, aluminum alloy, copper, copper alloy, nickel or copper-plated nickel and other metal materials; the battery cell 3 is a square battery cell with a winding or stacked structure and the pole ears on the same side.

[0043] like Fig.12 As shown, the positive electrode adapter 4 and the negative electrode adapter 5 are not limited to the pictures shown in the text, and square, oval and other special shapes are all within the protection scope.

[0044] The above are only preferred specific implementation methods of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes based on the technical solution and concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A square battery top cover with parallel cells, characterized in that ,include: A top cover assembly (2), the top cover assembly (2) being composed of a cover plate (21), an explosion-proof valve (24), an explosion-proof valve protective film (25), a positive pole (26), a negative pole (27), an insulating sealing plastic part (28), and an insulating plastic part (29); the cover plate (21) is integrally formed, and during the forming process, circular or polygonal protrusions are provided at both ends of the top of the cover plate (21), the protrusions being the positive pole (26); a positive pole concave part (261) is provided at the bottom of the cover plate (21) opposite to the positive pole (26), and the positive pole concave part (261) is used for laser welding with the positive electrode adapter (4); The negative pole column (27) is located in the middle of the cover plate (21), and the negative pole column (27) is insulated and sealed with the cover plate (21) by an insulating sealing plastic part (28); a negative pole column recess (271) is provided on the other side of the negative pole column (27), and the negative pole column recess (271) is used for laser welding with the negative electrode adapter (5).

2. The square battery top cover for parallel cells according to claim 1, characterized in that: The cover plate (21) is provided with a liquid injection hole (22) and an exhaust hole (23); an explosion-proof valve (24) is arranged below the exhaust hole (23); and the explosion-proof valve protection film (25) is fixed to the upper part of the exhaust hole (23) to prevent the explosion-proof valve (24) from being pierced by sharp objects and causing failure of the explosion-proof valve (24).

3. The square battery top cover of claim 1, characterized in that: When the top cover assembly (2) is assembled to the battery housing (1), when the gas pressure inside the battery rises to reach the upper explosion pressure limit of the explosion-proof valve (24), the explosion-proof valve (24) explodes, thereby achieving pressure relief inside the battery.

4. The square battery top cover for parallel cells according to claim 1, characterized in that: The insulating plastic part (29) is arranged at the bottom of the cover plate (21) and is used for insulation between the battery cells (3) and the negative electrode adapter (5) after internal connection, the cover plate (21), and the battery housing (1).

5. The cell-in-parallel square battery top cover according to claim 1, characterized in that: The cover plate (21), the positive pole (26) and the negative pole (27) are made of metal.

6. A square battery structure with parallel cells, characterized in that: The invention comprises a battery casing (1), a battery cell (3), a positive electrode adapter plate (4), a negative electrode adapter plate (5) and a battery top cover according to any one of claims 1 to 5, wherein the battery cell (3) is installed inside the battery casing (1), and a positive electrode tab (31) and a negative electrode tab (32) are provided at the upper end of the battery cell (3), the positive electrode tab (31) is connected to the positive electrode adapter plate (4), and the negative electrode tab (32) is connected to the negative electrode adapter plate (5), and the upper end of the battery casing (1) is encapsulated by a cover plate (21).

7. The cell-in-parallel square battery structure according to claim 6, characterized in that: The positive electrode adapter plate (4) and the negative electrode adapter plate (5) are made of metal.

8. The cell-in-parallel square battery structure according to claim 6, characterized in that: The battery cell (3) is a square battery cell with a wound or laminated structure and tabs on the same side.

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