Battery module

Abstract

The utility model provides a battery module, which relates to the technical field of battery modules and comprises a shell, a mounting chamber is arranged in the shell, a plurality of battery cells are mounted in mounting grooves in the mounting chamber, and the side surfaces and the bottom surfaces of the battery cells are separated from the mounting chamber to form cooling cavities surrounding the side surfaces and the bottom surfaces of the battery cells. And the cooling cavity is provided with a liquid inlet and a liquid outlet on two sides of the shell. The shell comprises a box body and a top cover assembly, a plurality of reinforcing ribs are distributed outside the box body, the top cover assembly sequentially comprises an upper cover plate, a current collecting row and a fixed cover from top to bottom, the fixed cover is used for fixing the upper end of the battery cell, a sealing piece is arranged between the fixed cover and the box body to form a first seal, and the current collecting row abuts against the box body to form a second seal. According to the utility model, cooling circulation and pressure relief are realized through the liquid inlet and the liquid outlet, when the battery cell is subjected to thermal runaway, cooling liquid can permeate into the battery cell to prevent explosion, and the reinforcing ribs outside the box body limit the damage of thermal runaway in the box body.

Description

Technical Field

[0001] The utility model relates to the technical field of battery modules, in particular to a battery module. Background Art

[0002] At present, with the increasing demand in new energy vehicles, electrochemical energy storage and other fields, battery modules are being used more and more widely. Among them, large-capacity cylindrical cells have become an important development direction in the field of battery module technology due to their high production efficiency, mature technology and high safety. However, cylindrical cells have poor radial heat dissipation. When the internal temperature of the battery exceeds a certain threshold, it may trigger a chain reaction, causing the battery module temperature to rise rapidly, and even cause a fire or explosion.

[0003] With the advancement of technology, more and more battery modules have introduced cooling structures such as heat sinks and cooling liquid pipes. However, the heat dissipation efficiency of heat sinks is low, and the cooling liquid pipes make the internal structure of the battery module complex and increase the volume, thereby reducing the energy density of the battery module. In addition, traditional modules usually glue the single battery cells into the module, making it difficult to replace a single battery cell. Utility Model Content

[0004] In order to overcome the defects of the prior art, the technical problem to be solved by the present invention is to propose a battery module, which adopts the following technical solutions:

[0005] A battery module comprises a shell, an installation chamber is arranged inside the shell, at least one battery cell is installed inside the installation chamber, and an electrode terminal is arranged on the top of the battery cell. It is characterized in that the side surface of the battery cell and the installation chamber are spaced apart from each other to form a cooling cavity surrounding the side surface of the battery cell, and the cooling cavity is provided with a liquid inlet and a liquid outlet on both sides of the shell.

[0006] As a further improvement, the plurality of battery cells are spaced apart from each other in the installation chamber, and the cooling cavity is connected to and surrounds the sides of the plurality of battery cells.

[0007] As a further improvement, the bottom surface of the above-mentioned installation chamber is provided with an installation groove for clamping the above-mentioned battery cell, and the above-mentioned installation groove is provided with a step surface for abutting the bottom of the battery cell, so that the inner bottom surface of the above-mentioned installation groove is spaced from the bottom of the battery cell to form another component of the above-mentioned cooling cavity.

[0008] As a further improvement, the shell includes a box body and a top cover assembly, the top cover assembly is detachably fixed to the upper end of the box body to form the installation chamber, and a sealing member is provided between the box body and the top cover assembly.

[0009] As a further improvement, the top cover assembly includes an upper cover plate, a current collector and a fixing cover from top to bottom. The fixing cover is used to fix the upper end of the battery cell and is provided with a plurality of fixing holes. The electrode terminals of the battery cell are passed through the fixing holes and abut against the current collector.

[0010] As a further improvement, the upper end surface of the box body is provided with a fixing groove, the sealing member is arranged around the fixing groove, and the fixing cover presses the sealing member and is fixedly connected to the fixing groove.

[0011] As a further improvement, the edge of the fixing hole is provided with a groove, the outer edge of the upper end of the battery cell is provided with a flange, the battery cell is passed through the fixing hole and placed in the upper installation chamber, and the flange and the groove fit together.

[0012] As a further improvement, the collector cover is arranged on the fixed cover, and the edge thereof abuts against the box body.

[0013] As a further improvement, the fixing cover and the collecting bar are fixedly connected to the fixing groove by bolts.

[0014] As a further improvement, the side wall of the installation chamber is provided with an arc surface, and the outside of the box body is provided with a plurality of reinforcing ribs.

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

[0016] First, the utility model sets an installation groove on the bottom surface of the installation chamber to clamp the bottom of the battery cell, fixes the top of the battery cell with a fixed cover, and forms a cooling chamber between the battery cell and the installation chamber. The coolant is circulated in the cooling chamber through the liquid inlet and the liquid outlet to cool the battery. Since the positive and negative pole terminals of the battery cell are set at the top, it is only necessary to seal at the top of the installation chamber. Through such a structure, the coolant fills the entire module, effectively improving the cooling efficiency of the battery module. At the same time, the structure is simple and does not occupy the module space.

[0017] Secondly, the utility model provides a step surface in the installation groove to form a gap between the bottom of the battery cell and the bottom of the installation groove, so that the coolant can flow into the gap to cool the bottom of the battery cell, thereby effectively improving the poor radial heat dissipation of the cylindrical battery cell.

[0018] Thirdly, the shell of the utility model includes a box body and a top cover assembly, and the top cover assembly is detachably fixed to the upper end of the box body. When a battery cell becomes abnormal and needs to be replaced, the abnormal battery cell can be taken out and replaced by removing the top cover assembly.

[0019] Fourthly, the utility model includes a first seal formed by a fixed cover, a sealing member and a box body, and also includes a second seal formed by a collecting bar and the box body, so as to further improve the overall sealing effect.

[0020] Fifth, in the utility model, the side wall of the installation room is provided with an arcuate surface, and the outside of the box is provided with a plurality of reinforcing ribs. When the battery module has thermal runaway, if damage occurs, the coolant can directly enter the battery cell to reduce the possibility of explosion. If the thermal runaway seriously causes the battery cell to explode, the above-mentioned arcuate surface and the reinforcing ribs on the outside of the box can limit the damage caused by the explosion to the inside of the box as much as possible to avoid causing greater losses. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solution of the implementation mode of the utility model, the following is a brief introduction to the drawings required for use in the implementation mode. It should be understood that the following drawings only show certain embodiments of the utility model and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 It is a schematic diagram of the explosion of the structure of the utility model;

[0023] Figure 2 It is a structural schematic diagram of the fixed cover in the utility model;

[0024] Figure 3 It is a structural schematic diagram of the box body in the utility model;

[0025] Figure 4 It is a top view of the box body in the utility model;

[0026] Figure 5 It is a front cross-sectional view of the box body in the utility model;

[0027] Figure 6 It is a front view of the box body in the utility model;

[0028] Figure 7 for Figure 5 The enlarged view of point A in the middle;

[0029] Figure 8 for Figure 5 Enlarged view of point B in the middle.

[0030] Reference numerals:

[0031] 1-battery cell; 2-box; 3-top cover assembly; 4-seal;

[0032] 11- flange;

[0033] 21-installation chamber; 211-installation slot; 2111-step surface; 21a-cooling chamber; 22-liquid inlet; 23-liquid outlet; 24-fixing slot; 25-reinforcement rib;

[0034] 31-upper cover; 32-collector bar; 33-fixing cover; 331-fixing hole; 3311-groove. DETAILED DESCRIPTION

[0035] In order to facilitate understanding by those skilled in the art, the structure of the present invention is further described in detail with reference to the accompanying drawings:

[0036] In the description of the present invention, the terms "first" and "second" are used only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. The orientation or position relationship indicated by the terms "portion", "side", "end", etc. is based on the orientation or position relationship shown in the drawings and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention.

[0037] like Figure 1 As shown, the present application provides a battery module, including a box body 2 and a top cover assembly 3, combined with Figure 5 The box body 2 and the top cover assembly 3 are buckled together to form an installation chamber 21. A plurality of battery cells 1 are installed inside the installation chamber 21. The top of the battery cell 1 is provided with an electrode terminal at the top cover assembly 3. The inner bottom surface of the box body 2 is provided with a mounting groove 211, and the mounting groove 211 is provided with a step surface 2111.

[0038] The bottoms of the plurality of battery cells 1 are embedded in the mounting groove 211 at intervals, and the bottom surfaces of the battery cells 1 are in contact with the step surface 2111, so that the bottom surfaces of the battery cells 1 and the bottom surfaces of the mounting groove 211 are spaced from each other, and there are intervals between the side surfaces of the plurality of battery cells 1 and the mounting chamber 21, and these intervals together form a cooling cavity 21a connecting the plurality of battery cells 1; the cooling cavity 21a is provided with a liquid inlet 22 and a liquid outlet 23, and the liquid inlet 22 is provided on both sides of the box body 2.

[0039] refer to Figure 3 , Figure 4 and Figure 5In a specific embodiment shown, three cylindrical cells 1 are arranged in the box 2, and the positive and negative terminals of the cells 1 are arranged at the upper end. The three cells 1 are arranged at intervals. More specifically, the installation chamber 21 is formed by three cylindrical cavities whose inner diameter is larger than the outer diameter of the cell 1, which are connected to each other. The lower end of the installation chamber 21 is provided with the above-mentioned step surface 2111 around the edge. The step surface 2111 is non-closed, ensuring that the bottom surface of the installation chamber 21 can be connected to each other, forming a cooling chamber 21a around the side wall and bottom surface of the cell 1. The coolant circulates through the liquid inlet 22 and the liquid outlet 23. At the same time, the gap formed between the bottom of the cell 1 and the bottom of the installation groove 211 can enable the coolant to circulate the cooling of the side and bottom of the cell 1, effectively improving the problem of poor radial heat dissipation of the cylindrical cell 1, and the structure is simple and does not occupy too much module space.

[0040] In particular, liquid flame retardant can also be filled and circulated in the cooling chamber 21a. When the battery cell 1 inside the box 2 experiences thermal runaway and is damaged, the coolant / liquid flame retardant can quickly enter the battery cell 1 to prevent the thermal runaway from further spreading, thereby controlling the hazard range within the box 2 and significantly reducing the hazards caused by the thermal runaway of the battery cell 1.

[0041] Further, refer to Figure 1 , Figure 3 as well as Figure 6 In one embodiment provided, a transverse reinforcing rib 25 is arranged around the middle of the outer side of the box body 2, and a plurality of longitudinal reinforcing ribs 25 are arranged perpendicular to the transverse reinforcing rib 25, and the inner wall of the box body 2, that is, the inner wall of the cooling chamber 21a, is provided with a plurality of arc structures. When a thermal runaway explosion occurs in the battery, the impact generated by the explosion will be transmitted inside the box body 2, and the arc surface structure can disperse the impact in multiple directions, thereby reducing damage to the box body 2 and the battery. The transverse reinforcing ribs 25 and the longitudinal reinforcing ribs 25 together form a grid-like skeleton structure, which can significantly improve the overall strength and stability of the box body 2. When a thermal runaway explosion occurs in the battery, the structure can effectively resist the impact force generated by the explosion and prevent the box body 2 from breaking or deforming, thereby limiting the explosion hazard to the inside of the box body 2 and avoiding affecting external equipment and causing greater damage.

[0042] like Figure 1 As shown, the top cover assembly 3 includes an upper cover plate 31, a current collector 32 and a fixing cover 33 from top to bottom. The fixing cover 33 is used to fix the upper end of the battery cell 1. Figure 2 The fixing cover 33 is provided with a plurality of fixing holes 331 , and the electrode terminals of the battery cell 1 are passed through the fixing holes 331 and abut against the BMS control components on the collector bar 32 .

[0043] refer to Figure 2In a specific embodiment shown, the lower end of the fixing cover 33 is rectangular, the middle part is convex upward and has three fixing holes 331, and the edge of the fixing hole 331 is provided with a groove 3311. Furthermore, the upper edge of the battery cell 1 package is provided with a flange 11. During installation, the battery cell 1 passes downward from the top of the fixing hole 331, and the flange 11 at the upper end of the battery cell 1 fits with the groove 3311 at the edge of the fixing hole 331. Due to the weight of the battery itself, the fixing cover 33 is pressed downward on the upper end of the box body 2 to achieve pre-installation and reduce the difficulty of subsequent fixed installation.

[0044] refer to Figure 3 In the embodiment shown, the box body 2 is a rectangular parallelepiped structure, and its upper end surface is concave downward to form a fixing groove 24 for installing the fixing cover 33. A sealing member 4 is arranged around the fixing groove 24, and the fixing cover 33 presses the sealing member 4 and is fixedly connected in the fixing groove 24.

[0045] Combination Figure 1 , Figure 5 and Figure 7 , the collector bar 32 is arranged between the upper cover plate 31 and the fixed cover 33, and the collector bar 32 is provided with a positive and negative terminal bus assembly (not shown in the figure) to realize the series or parallel connection between multiple battery cells 1. Specifically, the collector bar 32, the fixed cover 33 and the box body 2 are connected by bolts, and the box body 2 is provided with bolt holes at the four corners of the fixed groove 24. The bolts are sequentially passed through the collector bar 32 and the fixed cover 33 and then threadedly connected to the bolt holes at the four corners of the fixed groove 24. The edge of the collector bar 32 is provided with a connection hole, and the lower end surface of the upper cover plate 31 is provided with a connection column. After the collector bar 32 is fixedly connected to the fixed cover 33, the upper cover plate 31 is fixedly connected by inserting the connection hole through the connection column. Through the above structure, when a telecommunication failure occurs in the box body 2, the abnormal battery cell 1 can be taken out and replaced by disassembling the top cover assembly 3, and then the top cover assembly 3 can be reconnected, and each part of the top cover assembly 3 can be disassembled and replaced separately, which significantly reduces the difficulty of later maintenance of the product and improves the maintenance efficiency.

[0046] like Figure 1 , Figure 5 and Figure 7 As shown, when the top cover assembly 3 is buckled with the box body 2, the lower end surface of the collector bar 32 abuts against the outer edge of the upper end surface of the box body 2, wrapping the fixed cover 33 therein to form a double sealing structure. Specifically, the fixed cover 33, the box body 2 (or the fixed groove 24) and the seal 4 therebetween form a first seal, and the collector bar 32 is made of PVC material, which forms a second seal with the box body 2, further improving the overall sealing effect. As needed, the collector bar 32 can be made of soft PVC material, or hard PVC and a rubber cushion layer can be set on the contact surface with the box body 2 to improve the sealing effect.

[0047] In a specific embodiment, the collecting bar 32 also includes a sensor assembly, which includes a pressure sensor and a plurality of temperature sensors. The detection head of the pressure sensor extends into the cooling chamber 21a to detect the pressure inside the cooling chamber 21a. The detection ends of the plurality of temperature sensors are arranged at the electrode terminals of the plurality of battery cells 1 to detect the temperature at the terminals of the battery cells 1.

[0048] The above description is only the preferred implementation of the utility model, and is not intended to limit the utility model. For those skilled in the art, the utility model can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. A battery module, comprising a housing, an installation chamber (21) being arranged inside the housing, at least one battery cell (1) being installed inside the installation chamber (21), and an electrode terminal being arranged on the top of the battery cell (1), characterized in that: The side of the battery core (1) and the installation chamber (21) are spaced apart from each other to form a cooling chamber (21a) surrounding the side of the battery core (1); the cooling chamber (21a) is provided with a liquid inlet (22) and a liquid outlet (23) on both sides of the shell.

2. A battery module according to claim 1, characterized in that: The plurality of battery cells (1) are arranged in an installation chamber (21) at intervals from each other, and the cooling chamber (21a) is connected to and surrounds the sides of the plurality of battery cells (1).

3. A battery module according to claim 2, characterized in that: The bottom surface of the installation chamber (21) is provided with an installation groove (211) for clamping the battery cell (1), and the installation groove (211) is provided with a step surface (2111) for abutting the bottom of the battery cell (1), so that the inner bottom surface of the installation groove (211) and the bottom of the battery cell (1) are spaced apart to form another component of the cooling cavity (21a).

4. A battery module according to claim 1, characterized in that: The shell comprises a box body (2) and a top cover assembly (3); the top cover assembly (3) is detachably fixed to the upper end of the box body (2) to form the installation chamber (21); and a sealing member (4) is provided between the box body (2) and the top cover assembly (3).

5. A battery module as claimed in claim 4, characterized in that: The top cover assembly (3) comprises, from top to bottom, an upper cover plate (31), a current collector (32) and a fixing cover (33); the fixing cover (33) is used to fix the upper end of the battery cell (1), and is provided with a plurality of fixing holes (331); the electrode terminals of the battery cell (1) are passed through the fixing holes (331) and abut against the current collector (32).

6. A battery module according to claim 5, characterized in that: The upper end surface of the box body (2) is provided with a fixing groove (24), the sealing member (4) is arranged around the fixing groove (24), and the fixing cover (33) presses the sealing member (4) and is fixedly connected to the fixing groove (24).

7. A battery module according to claim 6, characterized in that: The edge of the fixing hole (331) is provided with a groove (3311), the outer edge of the upper end of the battery cell (1) is provided with a flange (11), the battery cell passes through the fixing hole (331) and is placed in the installation chamber, and the flange (11) and the groove (3311) fit each other.

8. A battery module according to claim 6, characterized in that: The collecting bar (32) is covered on the fixing cover (33), and its edge is in contact with the box body (2).

9. A battery module according to claim 8, characterized in that: The fixing cover (33) and the collecting bar (32) are fixedly connected to the fixing groove (24) by means of bolts.

10. A battery module according to claim 4, characterized in that: The side wall of the installation chamber (21) is provided with an arc-shaped surface, and the outside of the box body (2) is provided with a plurality of reinforcing ribs (25).

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