Combined integrated battery cell structure

Abstract

The utility model discloses a combined type integrated battery cell structure which comprises a battery cell shell, the battery cell shell is formed by jointly enclosing an integrated shell and two groups of symmetrically distributed battery cell end covers, a heat-conducting top plate is arranged at the top in the battery cell shell, a heat-conducting bottom plate is arranged at the bottom in the battery cell shell, and heat-conducting partition plates which are uniformly distributed at intervals are connected between the heat-conducting top plate and the heat-conducting bottom plate; a plurality of vertical interlayer spaces are formed between the heat-conducting partition plates and the battery cell shell and between the adjacent heat-conducting partition plates; an upper horizontal interlayer is formed between the heat-conducting top plate and the battery cell shell, a lower horizontal interlayer is formed between the heat-conducting bottom plate and the battery cell shell, and uniformly distributed through holes are formed in the heat-conducting top plate and the heat-conducting bottom plate corresponding to vertical interlayer spaces; a battery cell pole is arranged on the battery cell end cover; wherein one battery cell end cover is provided with an electrolyte injection port, and the other battery cell end cover is provided with a battery cell explosion-proof valve. According to the utility model, the assembly difficulty can be reduced, the production offline efficiency can be improved, the heat conductivity coefficient can be improved, the battery temperature consistency is improved, and the service life of the battery cell is guaranteed.

Description

Technical Field

[0001] The utility model belongs to the technical field of battery core structures, and in particular relates to a combined integrated battery core structure. Background Art

[0002] Winding and lamination are the two mainstream technical routes in the lithium battery manufacturing process. The winding process combines the positive and negative electrodes and the separator by winding, which has high consistency and low manufacturing cost; the lamination process stacks the positive and negative electrodes alternately like building blocks, which has high volume energy density. Blade battery cell electrodes adopt the lamination technology route.

[0003] Commercial vehicles have a higher demand for battery pack power, and battery packs generally increase power by increasing the number of cells connected in series. When blade cells are stacked in multiple layers or stacked for a long length, it is easy for the flatness of the planes forming the sides of the cells to be large, resulting in a small actual contact area between the sides of the cells and the heat exchange device, and low heat exchange efficiency. When a heat exchange device is arranged at the top or bottom of the cell, it is difficult for the blade cells to transfer heat quickly and evenly from one end to the other in the height direction; in the thickness direction, the thermal conductivity is also affected by the height of the stack, which is not conducive to the heat inside the cell being transferred to the cell casing, causing the actual service life of the cell to fall short of the estimated cycle life.

[0004] In addition, when the battery cells are assembled into battery packs, a large number of battery cells need to be stacked one by one, which complicates the process and reduces the efficiency of battery pack production. Utility Model Content

[0005] The purpose of the utility model is to provide a combined integrated battery cell structure, which can reduce the difficulty of assembly, avoid the problem of large flatness of the battery pack side, improve the production line efficiency, effectively improve the thermal conductivity, improve the battery temperature consistency, and ensure the service life of the battery cell.

[0006] To achieve the above-mentioned purpose, the utility model provides a combined integrated battery structure, including a battery shell, wherein the battery shell is formed by an integrated shell and two sets of symmetrically distributed battery end covers, wherein a heat-conducting top plate is provided at the top of the battery shell, and a heat-conducting bottom plate is provided at the bottom, and heat-conducting baffles evenly spaced and distributed are connected between the heat-conducting top plate and the heat-conducting bottom plate;

[0007] A plurality of vertical interlayer spaces are formed between the heat-conducting partition and the battery core housing and between adjacent heat-conducting partitions, and the vertical interlayer spaces are limitedly filled with pole piece diaphragms;

[0008] An upper horizontal interlayer is formed between the heat-conducting top plate and the battery cell shell, a lower horizontal interlayer is formed between the heat-conducting bottom plate and the battery cell shell, and evenly distributed through holes are provided on the heat-conducting top plate and the heat-conducting bottom plate corresponding to the vertical interlayer space;

[0009] The corresponding vertical interlayer spaces on the two groups of battery cell end covers are provided with battery cell poles, and the positive and negative battery cell poles are arranged in a staggered and parallel manner;

[0010] An electrolyte injection port is arranged on one of the battery cell end covers, and a battery cell explosion-proof valve is arranged on the other battery cell end cover.

[0011] As a further solution of the utility model: the electrolyte injection port is centrally arranged on the upper part of the battery cell end cover.

[0012] As a further solution of the utility model: the battery core explosion-proof valves are provided in multiple groups, corresponding one to one with the vertical interlayer spaces.

[0013] As a further solution of the utility model: when the vertical interlayer space is an even number, a positive battery cell pole and a negative battery cell pole are reserved at both ends of one of the battery cell end covers, and adjacent battery cell poles in the middle are connected in pairs by connecting plates, and adjacent battery cell poles on the other battery cell end cover are connected in pairs by connecting plates.

[0014] As a further solution of the utility model: when the vertical interlayer space is an odd number, the diagonals of the two groups of battery cell end covers are respectively reserved for positive battery cell poles and negative battery cell poles, and the remaining adjacent battery cell poles are connected in pairs through connecting sheets.

[0015] Compared with the prior art, the beneficial effects of the utility model are as follows:

[0016] The integrated shell is combined with the cell end cover to form a cell shell, and multiple cells can be combined into a combined cell. Compared with the original solution, the combined integrated cell structure reduces the thickness of two cell insulation films and one cell shell between every two interlayers, which reduces the cell quality and further improves the integration of the cell.

[0017] By setting a heat-conducting partition, a single small battery cell is combined into a large battery cell while retaining the advantages of the small battery cells being set separately. The heat-conducting partition has good thermal conductivity and can improve the temperature consistency inside the battery cell. At the same time, the heat-conducting partition can quickly conduct or import heat into the battery cell with the help of the heat exchange structure on the outer side of the battery cell, maintain the battery cell in a comfortable temperature range, and extend the cycle life of the battery cell.

[0018] The electrolyte flow channel is formed by the upper horizontal interlayer, the vertical interlayer space and the lower horizontal interlayer. During the battery charging and discharging process, when the temperature in the electrolyte flow channel differs, the electrolyte density changes, and the electrolyte can circulate in the electrolyte flow channel to balance the battery core temperature.

[0019] It can reduce tedious and complicated operation steps, improve assembly accuracy, avoid the problem of large flatness of the battery pack side, and reduce assembly cost and labor cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the structure of the first embodiment of the utility model Figure 1 .

[0021] Figure 2 This is a schematic diagram of the structure of the first embodiment of the utility model Figure 2 .

[0022] Figure 3 This is a schematic diagram of the structure of the second embodiment of the utility model Figure 1 .

[0023] Figure 4 This is a schematic diagram of the structure of the second embodiment of the utility model Figure 1 .

[0024] Figure 5 The utility model is a schematic diagram of the connection structure of the heat-conducting top plate, the heat-conducting bottom plate and the heat-conducting partition plate.

[0025] In the figure: 1. integrated shell, 2. battery cell end cover, 3. electrolyte filling port, 4. battery cell pole, 5. positive electrode mark, 6. connecting piece, 7. negative electrode mark, 8. thermal conductive bottom plate, 9. lower horizontal interlayer, 10. thermal conductive partition, 11. explosion-proof valve, 12. thermal conductive top plate, 13. through hole, 14. vertical interlayer space. DETAILED DESCRIPTION

[0026] The utility model will be further described below in conjunction with the accompanying drawings.

[0027] Embodiment 1: Figure 1 , Figure 2 and Figure 5 As shown, the combined integrated battery structure includes a battery shell, which is formed by an integrated shell 1 and two groups of symmetrically distributed battery end covers 2. The integrated design can not only reduce the assembly process and the difficulty of the process, but also reduce the amount of materials used, and improve the battery integration and energy density. A heat-conducting top plate 12 is provided on the top of the battery shell, and a heat-conducting bottom plate 8 is provided on the bottom. Evenly spaced heat-conducting partitions 10 are connected between the heat-conducting top plate 12 and the heat-conducting bottom plate 8; the heat-conducting partitions 10, the heat-conducting top plate 12, and the heat-conducting bottom plate 8 are all made of materials with high thermal conductivity, such as copper-aluminum alloy, which is conducive to conducting the heat generated locally to the area with lower temperature, thereby reducing the probability of thermal runaway of the battery cell;

[0028] A plurality of vertical interlayer spaces 14 are formed between the heat-conducting baffle 10 and the cell housing, and between adjacent heat-conducting baffles 10, and the vertical interlayer spaces 14 are limitedly filled with pole piece diaphragms (not shown in the figure);

[0029] An upper horizontal interlayer is formed between the heat-conducting top plate 12 and the battery cell shell, and a lower horizontal interlayer 9 is formed between the heat-conducting bottom plate 8 and the battery cell shell. The heat-conducting top plate 12 and the heat-conducting bottom plate 8 are provided with evenly distributed through holes 13 corresponding to the vertical interlayer space 14; so that the upper horizontal interlayer, the lower horizontal interlayer 9 and the vertical interlayer space 14 form an electrolyte flow channel, which is conducive to quickly conducting the heat generated locally during the charging and discharging process to the area with lower temperature, increasing the temperature consistency of the integrated battery cell and reducing the risk of thermal runaway of the battery cell;

[0030] The corresponding vertical interlayer spaces 14 on the two groups of battery cell end covers 2 are both provided with battery cell poles 4, and the positive and negative battery cell poles 4 are arranged in a staggered and parallel manner;

[0031] An electrolyte injection port 3 is provided on one of the battery cell end covers 2 , and a battery cell explosion-proof valve 11 is provided on the other battery cell end cover 2 .

[0032] The combined integrated cell structure combines multiple cells into one, which not only retains the high voltage of traditional independent cells in series, but also has the advantages of highly integrated single cells. The combined integrated cell structure can reduce material usage, reduce process difficulty, and reduce the number of processes.

[0033] In addition, the characteristics of traditional battery cell structures result in the cells being made of anisotropic materials. The combined integrated battery cell structure uses high thermal conductivity materials that intersect horizontally and vertically inside, allowing the electrolyte to circulate within the battery cell, further reducing the anisotropy caused by the internal structure of the battery cell.

[0034] In order to facilitate the electrolyte to flow from the middle to both sides during electrolyte injection, preferably, the electrolyte injection port 3 is centrally arranged on the upper part of the battery cell end cover 2.

[0035] In order to facilitate the battery cell to quickly eject the contents in a vertical interlayer space 14 when thermal runaway occurs, further, multiple groups of battery cell explosion-proof valves 11 are provided, corresponding one to one to the vertical interlayer spaces 14, and all battery cell explosion-proof valves 11 are located on the same battery cell end cover 2, which is convenient for designing the thermal runaway eruption channel to avoid mutual influence between high-temperature erupting materials and electrical connectors, thereby causing secondary hazards of thermal runaway.

[0036] When the vertical interlayer space 14 is an even number, a battery pole 4 with a positive pole mark 5 and a battery pole 4 with a negative pole mark 7 are reserved at both ends of one of the battery cell end covers 2, and adjacent battery poles 4 in the middle are connected in pairs by connecting plates 6, and adjacent battery poles 4 on the other battery cell end cover 2 are connected in pairs by connecting plates 6.

[0037] Embodiment 2, as Figure 3 and Figure 4 As shown, different from the first embodiment, the vertical interlayer space 14 is an odd number, and the distribution of the battery cell poles 4 is adjusted.

[0038] When the vertical interlayer space 14 is an odd number, the diagonals of the two groups of cell end covers 2 are reserved for the cell poles 4 with the positive pole mark 5 and the cell poles 4 with the negative pole mark 7 , respectively, and the remaining adjacent cell poles 4 are connected in pairs through the connecting pieces 6 .

[0039] The adjacent cell poles 4 of the combined integrated battery structure are connected in series by connecting plates 6. When the connecting plates 6 connect the positive and negative cell poles 4, the number of cell poles 4 and the arrangement of the cells in the battery pack need to be considered. Finally, the combined integrated battery structure outputs a positive cell pole 4 and a negative cell pole 4. The voltage of the single battery is determined by the number of thermally conductive partitions 10, that is, the number of cell combinations.

Claims

1. A combined integrated battery cell structure, including a battery cell housing, characterized in that: The battery cell housing is formed by an integrated housing (1) and two groups of symmetrically distributed battery cell end covers (2), a heat-conducting top plate (12) is provided at the top of the battery cell housing, a heat-conducting bottom plate (8) is provided at the bottom, and evenly spaced heat-conducting baffles (10) are connected between the heat-conducting top plate (12) and the heat-conducting bottom plate (8); A plurality of vertical interlayer spaces (14) are formed between the heat-conducting partition (10) and the battery cell housing, and between adjacent heat-conducting partitions (10), and the vertical interlayer spaces (14) are limitedly filled with pole piece diaphragms; An upper horizontal interlayer is formed between the heat-conducting top plate (12) and the battery cell shell, a lower horizontal interlayer (9) is formed between the heat-conducting bottom plate (8) and the battery cell shell, and evenly distributed through holes (13) are provided in the corresponding vertical interlayer spaces (14) on the heat-conducting top plate (12) and the heat-conducting bottom plate (8); The corresponding vertical interlayer spaces (14) on the two groups of battery cell end covers (2) are both provided with battery cell poles (4), and the positive and negative battery cell poles (4) are arranged in a staggered and parallel manner; One of the battery cell end covers (2) is provided with an electrolyte injection port (3), and the other battery cell end cover (2) is provided with a battery cell explosion-proof valve (11).

2. The combined integrated battery cell structure according to claim 1, characterized in that: The electrolyte injection port (3) is centrally arranged on the upper part of the battery cell end cover (2).

3. The combined integrated battery cell structure according to claim 2, characterized in that: The battery core explosion-proof valves (11) are provided in multiple groups, corresponding one to one with the vertical interlayer spaces (14).

4. The combined integrated battery cell structure according to any one of claims 1 to 3, characterized in that: When the number of vertical interlayer spaces (14) is an even number, a cell pole (4) with a positive pole mark (5) and a cell pole (4) with a negative pole mark (7) are reserved at both ends of one of the cell end covers (2), adjacent cell poles (4) in the middle are connected in pairs via connecting pieces (6), and adjacent cell poles (4) on the other cell end cover (2) are connected in pairs via connecting pieces (6).

5. The combined integrated battery cell structure according to any one of claims 1 to 3, characterized in that: When the vertical interlayer space (14) is an odd number, the diagonals of the two groups of battery cell end covers (2) respectively reserve battery cell poles (4) with positive pole markings (5) and battery cell poles (4) with negative pole markings (7), and the remaining adjacent battery cell poles (4) are connected in pairs via connecting sheets (6).

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