Battery module and battery pack

Abstract

The battery module comprises a plurality of battery cells, the battery cells are arranged in the thickness direction of the battery cells, the battery cells are provided with end faces which are oppositely arranged in the height direction of the battery cells, and the battery cells are provided with first side faces which are oppositely arranged in the thickness direction of the battery cells; the plurality of heat dissipation plates are sequentially arranged among the battery cells, each heat dissipation plate comprises a first heat dissipation part and a second heat dissipation part which are connected with each other, the first heat dissipation part is attached to the first side surface, and the second heat dissipation part is attached to the end surface; the liquid cooling plate is arranged on the sides, close to the end face, of the battery cells, the liquid cooling plate is connected with the second heat dissipation part, and the technical problem that directional temperature difference exists in the battery cells in the battery heat dissipation structure is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of battery heat dissipation, and in particular to a battery module and a battery pack. Background Art

[0002] Batteries generate a lot of heat during the charging and discharging process, especially in the case of high-power discharge and fast charging. The accumulation of heat may lead to a decline in battery performance, shortened life, and even cause safety accidents. Therefore, how to effectively manage the heat inside the battery and ensure that the battery operates within a safe and stable temperature range is a key issue in battery design.

[0003] In the existing battery heat dissipation structure, the liquid cooling plate is usually set at one end of the battery cell, and the heat generated by the cell is taken away by the flow of liquid cooling fluid, thereby maintaining the temperature of the cell stable. However, since the liquid cooling plate is only set at one end of the cell, the liquid cooling system can only dissipate heat for a part of the battery area, thereby generating a temperature difference in the longitudinal direction of the cell. The existence of temperature difference not only affects the overall thermal management effect of the battery, but may also cause thermal imbalance inside the battery, thereby affecting the performance and life of the battery.

[0004] Therefore, how to improve the battery heat dissipation structure and reduce the temperature difference in the direction of the battery cell has become an urgent problem to be solved. Summary of the invention

[0005] An object of the present invention is to provide a battery module and a battery pack, which are intended to solve the technical problem of directional temperature difference in battery cells in a battery heat dissipation structure.

[0006] To achieve the above-mentioned purpose, the present invention provides a solution: a battery module, which includes a plurality of battery cells arranged along the thickness direction, the battery cells have oppositely arranged end faces along the height direction, and oppositely arranged first side faces along the thickness direction; a plurality of heat dissipation plates, which are sequentially arranged between the battery cells, the heat dissipation plates include a first heat dissipation portion and a second heat dissipation portion connected to each other, the first heat dissipation portion is bonded to the first side face, and the second heat dissipation portion is bonded to the end face; a liquid cooling plate, which is arranged on one side of the plurality of battery cells close to the end face, and the liquid cooling plate is connected to the second heat dissipation portion.

[0007] Optionally, a contact area between the first heat dissipation portion and the first side surface is S1, a contact area between the second heat dissipation portion and the end surface is S2, H1=S1 / S2, wherein 1.5≤H1≤3.5.

[0008] Optionally, the battery cell also has a second side surface arranged opposite to each other along its length direction, and the heat dissipation plate also includes a third heat dissipation part, which is interconnected with the first heat dissipation part and the second heat dissipation part, and the third heat dissipation part is in contact with the second side surface, and the first side surface is larger than the second side surface.

[0009] Optionally, a contact area between the third heat dissipation portion and the second side surface is S3, H2=(S1+S3) / S2, wherein 1.5≤H2≤3.5.

[0010] Optionally, the heat dissipation plate is provided with a heat dissipation cavity, which is in a vacuum state and filled with acetaldehyde.

[0011] Optionally, the heat dissipation plate further comprises a porous structure layer, which is formed by sintered copper powder and adheres to the inner wall of the heat dissipation cavity.

[0012] Optionally, the battery module further includes adhesive glue, which is sandwiched between the heat sink and the battery cell.

[0013] Optionally, the end surface includes a first end surface and a second end surface that are arranged opposite to each other; the battery cell also includes a pressure relief valve, the pressure relief valve is arranged on the first end surface, the second heat dissipation portion is attached to the second end surface, and the liquid cooling plate is arranged on a side of the battery cell close to the second end surface.

[0014] Optionally, the battery module further includes a thermally conductive adhesive layer, which is arranged on the second end surface, and the opposite ends of the thermally conductive adhesive layer are respectively connected to the second heat dissipation parts of the adjacent heat dissipation plates, and the liquid cooling plate is connected to the second heat dissipation part and the thermally conductive adhesive layer.

[0015] Optionally, a groove is provided on a side of the liquid cooling plate close to the battery cell, and the groove is filled with a thermal conductive adhesive layer.

[0016] Optionally, the liquid cooling plate is provided with a flow channel and a liquid inlet and a liquid outlet connected to the flow channel; the flow channel includes a plurality of first flow channels and a plurality of second flow channels, the first flow channels and the second flow channels are connected end to end in sequence, and the first flow channels and the second flow channels are alternately arranged.

[0017] In order to achieve the above object, the present invention further provides a solution: a battery pack, comprising the above battery module.

[0018] The beneficial effects of the present invention are:

[0019] Compared with the prior art that only sets a liquid cooling plate on the end face of the battery cell, the present application sets a heat dissipation plate between the battery cells, and the first heat dissipation part and the second heat dissipation part connected to each other by the heat dissipation plate are respectively attached to the first side face and the end face of the battery cell, thereby establishing a double heat conduction path. The first heat dissipation part is responsible for horizontally conducting the heat on the side face of the battery cell to the second heat dissipation part, while the second heat dissipation part is responsible for both vertically conducting the heat on the end face of the battery cell and guiding the heat transferred by the first heat dissipation part to the liquid cooling plate. The temperature difference of the battery cell in the height direction is reduced, the local overheating phenomenon is effectively alleviated, and the overall thermal management performance of the battery module is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0021] Figure 1 is a schematic structural diagram of a battery module provided by an embodiment of the present invention;

[0022] Figure 2 is an exploded schematic diagram of a cell-related structure provided by an embodiment of the present invention;

[0023] Figure 3 The embodiment of the present invention provides Figure 2 The main view;

[0024] Figure 4 is an exploded schematic diagram of another battery cell related structure provided by an embodiment of the present invention;

[0025] Figure 5 is a cross-sectional view of a heat sink provided by an embodiment of the present invention;

[0026] Figure 6 is a top view of a battery module provided by an embodiment of the present invention;

[0027] Figure 7 The embodiment of the present invention provides Figure 6 Sectional view in the AA direction;

[0028] Figure 8 The embodiment of the present invention provides Figure 7 A partial enlarged view of the middle A area;

[0029] Fig. 9 is a schematic structural diagram of a liquid cooling plate provided in an embodiment of the present invention;

[0030] Fig.10 is a side view of a battery module provided by an embodiment of the present invention;

[0031] Fig.11 The embodiment of the present invention provides Fig.10 Cross-sectional view along the BB direction.

[0032] Description of Figure Numbers:

[0033] 10. Battery cell; 11. End face; 111. First end face; 112. Second end face; 12. First side face; 13. Second side face; 14. Pressure relief valve; 20. Heat sink; 21. First heat sink; 22. Second heat sink; 23. Third heat sink; 24. Heat sink cavity; 25. Porous structure layer; 30. Liquid cooling plate; 31. Groove; 32. Flow channel; 321. First flow channel; 322. Second flow channel; 33. Liquid inlet; 34. Liquid outlet; 40. Adhesive; 50. Thermal conductive adhesive layer. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] See also Figures 1 to 3 , Figure 1 is a schematic diagram of the structure of a battery module provided by an embodiment of the present invention, Figure 2 is an exploded schematic diagram of the relevant structure of the battery cell 10 provided in an embodiment of the present invention, Figure 3 The embodiment of the present invention provides Figure 2 main view.

[0036] The embodiment of the present invention provides a battery module, which aims to alleviate the problem of large longitudinal temperature difference in traditional battery modules. The battery module includes a plurality of battery cells 10, a plurality of heat sinks 20 and a liquid cooling plate 30. The battery cells 10 are arranged in sequence along the thickness direction thereof, and each battery cell 10 has end faces 11 arranged oppositely in the height direction and first side faces 12 arranged oppositely in the thickness direction. Figure 1 The A direction is the height direction of the battery cell 10 , and the B direction is the thickness direction of the battery cell 10 .

[0037] The heat sink 20 fits tightly with the battery cell 10 to optimize the heat transfer path. Specifically, the heat sink 20 is arranged between adjacent battery cells 10, and each heat sink 20 includes two parts: a first heat sink 21 and a second heat sink 22. The first heat sink 21 is arranged along the first side surface 12 of the battery cell 10, fits the first side surface 12 of the battery cell 10, and is mainly used to absorb the heat generated by the first side surface 12 of the battery cell 10. The second heat sink 22 extends from the first heat sink 21, fits tightly with the end surface 11 of the battery cell 10, and is connected to the liquid cooling plate 30. The liquid cooling plate 30 is arranged along one side of the end surface 11 of multiple battery cells 10, and is in direct contact with the second heat sink 22 of the heat sink 20, forming a continuous heat conduction path from the first side surface 12 of the battery cell 10 to the end surface 11 and then to the liquid cooling plate 30.

[0038] In this embodiment, on the one hand, the first side surface 12 of the battery cell 10 is attached to the first heat dissipation part 21, and the heat generated by the side surface of the battery cell 10 is quickly transferred to the second heat dissipation part 22 through the heat dissipation plate 20 material with high thermal conductivity. On the other hand, the end surface 11 of the battery cell 10 is directly in contact with the second heat dissipation part 22, and the heat is efficiently transferred to the liquid cooling plate 30 through the second heat dissipation part 22. In the liquid cooling plate 30, the flow of the coolant further takes away the heat, achieving rapid heat dissipation.

[0039] From the analysis of the heat conduction path, the first heat dissipation part 21 is responsible for horizontally conducting the heat on the side of the battery cell 10 to the second heat dissipation part 22, while the second heat dissipation part 22 is responsible for vertically conducting the heat on the end surface 11 of the battery cell 10 and guiding the heat transferred by the first heat dissipation part 21 to the liquid cooling plate 30. Therefore, the heat in the height direction (longitudinal direction) and thickness direction (lateral direction) of the battery cell 10 can be effectively transferred, avoiding the temperature difference problem caused by heat dissipation only on the end surface 11 of the battery cell 10 in the traditional structure.

[0040] At the same time, the heat sink 20 plays a structural supporting role between the battery cells 10, which can alleviate the impact of thermal expansion between the battery cells 10 and improve the overall mechanical stability of the module, making it suitable for high power output and long battery life application scenarios.

[0041] Furthermore, in order to optimize the thermal load distribution and heat dissipation requirements of the battery module, in the battery module, the contact area between the first heat dissipation portion 21 and the first side surface 12 is S1, the contact area between the second heat dissipation portion 22 and the end surface 11 is S2, and H1 is set to S1 / S2, where 1.5≤H1≤3.5.

[0042] The battery module transfers heat to the heat sink 20 through two areas, S1 and S2, where S1 is the contact area between the battery cell 10 and the first heat sink 21 of the heat sink 20, which mainly bears the heat conduction from the first side 12 of the battery cell 10, and S2 is the contact area between the battery cell 10 and the second heat sink 22 of the heat sink 20, which mainly bears the heat conduction from the end face 11 of the battery cell 10. These two contact areas jointly transfer the heat generated by the battery cell 10 to the heat sink 20. The heat sink 20 then further conducts the heat to the coolant through its contact with the liquid cooling plate 30. The contact area between the liquid cooling plate 30 and the second heat sink 22 is equal to S2.

[0043] When H1 is too large, the first heat dissipation part 21 of the heat dissipation plate 20 occupies a larger contact area, while the contact area of ​​the second heat dissipation part 22 is smaller. Since the area of ​​the second heat dissipation part 22 is smaller, the contact area between the liquid cooling plate 30 and the second heat dissipation part 22 is equal to S2, and the heat cannot be effectively transferred to the liquid cooling plate 30, resulting in the liquid cooling plate 30 in the heat dissipation system not being able to play its due role, thereby affecting the overall heat dissipation efficiency.

[0044] When H1 is too small, the contact area between the first heat dissipation portion 21 of the heat dissipation plate 20 and the first side surface 12 of the battery cell 10 is insufficient, and the heat from the side surface cannot be effectively transferred to the heat dissipation plate 20. At this time, most of the heat in the heat dissipation system cannot be effectively transferred from the side surface to the heat dissipation plate 20, which may cause local overheating or even out-of-control of the temperature of the battery module.

[0045] In this embodiment, by setting H1 within the range of 1.5≤H1≤3.5, it is possible to ensure that the heat conduction efficiency of the battery module is balanced in both aspects. This allows the heat of the heat sink 20 to be properly distributed between the first side surface 12 and the end surface 11, ensuring that the heat of the battery cell 10 can be effectively transferred to the heat sink 20 and removed through the liquid cooling plate 30, while avoiding the problem of local overheating, thereby improving the safety, performance and service life of the battery.

[0046] In some embodiments, see Figure 4 , Figure 4 1 is an exploded schematic diagram of another structure related to the battery cell 10 provided in an embodiment of the present invention. In order to further improve the heat dissipation performance of the battery module, the battery cell 10 also has a second side surface 13 arranged opposite to each other along its length direction. At the same time, the heat dissipation plate 20 adds a third heat dissipation portion 23 to enhance the comprehensive coverage and heat transfer efficiency of the heat dissipation system. The third heat dissipation portion 23 is interconnected with the first heat dissipation portion 21 and the second heat dissipation portion 22 of the heat dissipation plate 20 to form an integral heat dissipation structure, and the third heat dissipation portion 23 is tightly fitted with the second side surface 13 of the battery cell 10.

[0047] In this embodiment, the second side surface 13 of the battery cell 10 is another area in the battery cell 10 where heat may accumulate. In order to ensure that the heat on this side can be effectively dissipated, the third heat dissipation portion 23 of the heat dissipation plate 20 is attached to the second side surface 13 of the battery cell 10, forming a fully covered heat dissipation system. The third heat dissipation portion 23 continues the heat dissipation function of the first heat dissipation portion 21 and the second heat dissipation portion 22, further improving the heat dissipation efficiency of the battery cell 10.

[0048] The heat dissipation area of ​​the first side surface 12 is larger than that of the second side surface 13. This is because the structural characteristics of the battery cell 10 usually cause the first side surface 12 to bear a higher heat load, and more concentrated heat will be generated during the operation of the battery. Therefore, the area of ​​the first heat dissipation portion 21 is relatively large, so as to more effectively absorb and disperse the heat from the battery cell 10.

[0049] Through the multi-directional heat conduction setting, the battery module can simultaneously exchange heat in multiple directions, forming a three-dimensional heat dissipation effect, avoiding the problem of excessive local temperature difference. Specifically, the first side 12 contacts the first heat dissipation part 21, and conducts the heat generated by the battery cell 10 to the heat dissipation plate 20. The second side 13 contacts the heat dissipation plate 20 through the third heat dissipation part 23 to ensure that its heat can be effectively dissipated. In addition, the design of the second heat dissipation part 22 takes into account the contact between the end face 11 and the liquid cooling plate 30, so that the heat at the top and bottom of the battery cell 10 can also be quickly taken away through the liquid cooling plate 30.

[0050] Furthermore, when the third heat dissipation part 23 is added to the heat dissipation plate 20, the third heat dissipation part 23 is tightly fitted with the second side surface 13 of the battery cell 10 to form an additional heat dissipation path. In order to optimize heat conduction, the contact area between the third heat dissipation part 23 and the second side surface 13 is S3, and H2 is set to (S1+S3) / S2, where 1.5≤H2≤3.5.

[0051] The battery module transfers heat to the heat sink 20 through three areas S1, S2 and S3. S1 is the contact area between the first heat sink 21 and the first side surface 12, which is mainly responsible for conducting the heat from the first side surface 12 of the battery cell 10. S2 is the contact area between the second heat sink 22 and the end surface 11, which is mainly responsible for the heat conduction from the end surface 11 of the battery cell 10. S3 is the contact area between the third heat sink 23 and the second side surface 13, which is responsible for heat conduction with the second side surface 13 of the battery cell 10. The heat sink 20 then further conducts the heat to the coolant through its contact with the liquid cooling plate 30. The contact area between the liquid cooling plate 30 and the second heat sink 22 is equal to S2.

[0052] If H2 is too large, the contact area between the heat sink 20 and the liquid cooling plate 30 is limited, which may cause the heat sink 20 to be unable to effectively transfer the heat from the end surface 11 to the liquid cooling plate 30, thereby reducing the cooling efficiency. If H2 is too small, the contact area between the first heat sink 21 and the third heat sink 23 of the heat sink 20 is insufficient, and the heat from the side of the battery cell 10 cannot be effectively transferred to the heat sink 20, resulting in excessively high temperatures on the side of the battery cell 10, resulting in uneven temperature distribution of the battery module, affecting the safety and life of the battery.

[0053] In this embodiment, H2 is set within the range of 1.5≤H2≤3.5, the total contact area of ​​the first heat dissipation part 21 and the third heat dissipation part 23 is moderate, and heat exchange can be effectively performed with the two sides of the battery core 10, and the heat dissipation plate 20 has sufficient contact area to effectively transfer heat with the liquid cooling plate 30. The heat dissipation system can maintain good heat balance and avoid local overheating and insufficient cooling.

[0054] In some embodiments, see Figure 5 , Figure 52 is a cross-sectional view of a heat sink 20 provided in an embodiment of the present invention. A heat sink cavity 24 is provided inside the heat sink 20. The heat sink cavity 24 is a sealed internal space, which is in a vacuum state and filled with a working medium with high thermal conductivity, such as acetaldehyde. The heat sink 20 not only relies on the solid thermal conductivity of the metal material, but also utilizes the vapor-liquid phase change characteristics of acetaldehyde in a vacuum environment, thereby significantly improving the overall thermal conductivity.

[0055] Specifically, a stable vacuum state is maintained in the heat dissipation cavity 24. This helps to reduce the thermal resistance of gas molecules, thereby minimizing convection losses during heat transfer. At the same time, acetaldehyde, as a heat-conducting medium with a low boiling point, evaporates rapidly when absorbing heat, transferring heat from high-temperature areas (such as the side and end faces 11 of the battery cell 10) to the other end of the heat sink 20. In the lower temperature area, acetaldehyde vapor condenses to release heat, forming an efficient vapor-liquid phase change cycle, transferring heat to the liquid cooling plate 30, which is then taken away by the coolant. This cycle is carried out continuously, thereby achieving efficient and stable heat transfer.

[0056] In this embodiment, compared with the traditional metal heat sink 20 structure, the heat dissipation structure based on phase change has higher thermal conductivity, which can effectively alleviate the heat accumulation inside the battery cell 10 and reduce the temperature difference. In particular, in terms of the uneven heat dissipation problem in the height direction of the battery cell 10, due to the improvement of thermal conductivity, the longitudinal temperature distribution of the battery cell 10 can be significantly improved, ensuring that the entire battery module maintains a stable operating temperature under high power and long-term operation conditions.

[0057] Furthermore, in order to enhance the overall thermal conductivity of the heat sink 20 and improve the heat transfer efficiency, the heat sink 20 further includes a porous structure layer 25. The porous structure layer 25 is adhered to the inner wall of the heat sink cavity 24. The porous structure layer 25 adopts a sintering process, by sintering copper powder particles at high temperature and appropriate pressure into a metal layer with a large number of tiny pores. The pores form a complex three-dimensional network structure on the inner wall surface of the heat sink cavity 24, which significantly increases the inner wall contact area of ​​the heat sink 20, thereby improving the heat transfer efficiency between the inner wall and the working medium (such as acetaldehyde).

[0058] In this embodiment, the porous structure layer 25 plays a role in strengthening heat exchange during the phase change heat transfer process, and improves the thermal conductivity of the heat sink 20. During the heat dissipation process, when the working medium acetaldehyde in the heat dissipation cavity 24 is heated and evaporated, the vapor molecules will quickly diffuse to the area with lower temperature. The presence of the porous structure layer 25 accelerates this process. On the one hand, the large surface area of ​​the porous layer enhances the condensation effect of acetaldehyde vapor, allowing it to release heat faster and condense into liquid; on the other hand, the condensed liquid acetaldehyde will automatically flow back to the high temperature area along the tiny channels and capillary pores of the porous structure layer 25, forming an efficient circulation flow mechanism. This capillary action effectively avoids the accumulation and retention of the working medium in the heat dissipation cavity 24, ensures the continuous phase change process of the working medium, and thus achieves rapid and uniform heat transfer.

[0059] In some embodiments, see Figures 6 to 8 , Figure 6 is a top view of a battery module provided by an embodiment of the present invention, Figure 7 The embodiment of the present invention provides Figure 6 Sectional view along the AA direction, Figure 8 The embodiment of the present invention provides Figure 7 The battery module also includes an adhesive 40. The adhesive 40 is sandwiched between the heat sink 20 and the battery cell 10. On the one hand, it improves the heat conduction efficiency between the heat sink 20 and the battery cell 10. On the other hand, it enhances the mechanical connection strength between the two, ensuring the structural stability of the battery module under long-term operation and complex working conditions.

[0060] In this embodiment, during the actual assembly process, the surfaces of the battery cell 10 and the heat sink 20 may have a certain degree of roughness or slight unevenness, and direct contact may lead to the generation of local air gaps. The thermal conductivity of air is poor, and it is easy to form "thermal resistance points", which affects the heat transfer efficiency. The adhesive 40 has high thermal conductivity and good flexibility. By applying the adhesive 40 between the battery cell 10 and the heat sink 20, these gaps can be effectively filled, thereby reducing the interface thermal resistance and significantly improving the thermal conductivity between the battery cell 10 and the heat sink 20.

[0061] From the perspective of structural fixation, the adhesive 40 can also play the role of adhesion and buffering. Its high adhesion strength ensures a stable connection between the heat sink 20 and the battery cell 10, avoiding the loosening and displacement of the battery during vibration, impact or thermal expansion and contraction. In addition, the elastic properties of the adhesive 40 can effectively buffer the stress caused by the thermal expansion of the battery module during operation, thereby extending the service life of the module and reducing the risk of mechanical fatigue and material aging.

[0062] Furthermore, in the battery module structure, the end face 11 of each battery cell 10 includes a first end face 111 and a second end face 112 that are arranged opposite to each other. In order to improve the safety of the battery module, the battery cell 10 is also provided with a pressure relief valve 14, which is arranged on the first end face 111. When the internal pressure of the battery cell 10 is too high, the pressure relief valve 14 can automatically open to quickly release excess gas to prevent expansion or even explosion accidents caused by pressure accumulation inside the battery.

[0063] To optimize the thermal management performance, the second heat dissipation portion 22 of the heat sink 20 is bonded to the second end face 112 of the battery cell 10, and the liquid cooling plate 30 is arranged along one side of the battery cell 10 close to the second end face 112, and is directly connected to the second heat dissipation portion 22 of the heat sink 20, so that the heat of the end face 11 can be efficiently transferred to the liquid cooling plate 30 through the heat sink 20.

[0064] In this embodiment, the pressure relief valve 14 is separately arranged on the first end surface 111, avoiding interference between the cooling structure and the pressure relief structure. Once abnormal thermal runaway occurs inside the battery cell 10, the pressure relief valve 14 can release pressure and high-temperature gas in time to prevent the accident from spreading. The second heat dissipation part 22 and the liquid cooling plate 30 are centrally arranged on the second end surface 112, making this area the main heat dissipation outlet of the battery cell 10, ensuring that heat can be concentratedly and efficiently dissipated to reduce temperature accumulation.

[0065] In addition, from a safety perspective, the setting direction of the pressure relief valve 14 is opposite to the cooling direction of the heat dissipation system. Once thermal runaway occurs, the released high-temperature gas will stay away from the liquid cooling plate 30 to avoid heat from affecting the heat dissipation system in reverse, thereby improving the overall safety of the battery module.

[0066] In some embodiments, the battery module further includes a thermally conductive adhesive layer 50. The thermally conductive adhesive layer 50 is arranged on the second end surface 112 of the battery cell 10 to enhance the thermal contact effect between the battery cell 10 and the heat sink 20 and the liquid cooling plate 30, fill the area not covered by the second heat dissipation portion 22 of the heat sink 20, reduce local thermal resistance, and thus achieve more uniform heat transfer.

[0067] The two ends of the thermally conductive adhesive layer 50 are respectively connected to the second heat dissipation portion 22 of the adjacent heat dissipation plate 20, ensuring that the second end surface 112 of the battery cell 10 forms a continuous heat conduction path with the multiple heat dissipation plates 20. At the same time, the liquid cooling plate 30 is in close contact with the second heat dissipation portion 22 of the heat dissipation plate 20 and the thermally conductive adhesive layer 50, constructing a complete thermal management network, so that the entire second end surface 112 of the battery cell 10 can effectively participate in the heat transfer and heat dissipation process.

[0068] In this embodiment, the thermal conductive adhesive layer 50 is generally made of silicone, epoxy resin or thermal interface composite material with high thermal conductivity and good flexibility. The thermal conductive adhesive layer 50 serves as an auxiliary heat conductive medium, covers the portion of the second end surface 112 of the battery cell 10 that is not covered by the second heat dissipation portion 22, diffuses the heat to the liquid cooling plate 30, and removes it through the circulation of the coolant, thereby achieving efficient heat dissipation.

[0069] Structurally, the thickness and distribution of the thermally conductive adhesive layer 50 can be customized according to the actual application scenario. In areas with higher heat dissipation requirements, the thermally conductive adhesive layer 50 can be designed to be locally thickened to enhance the heat conduction capacity of specific areas. In scenarios where overall heat dissipation balance is required, a uniform coverage design can be adopted to ensure that the entire second end surface 112 of the battery cell 10 is in a good thermal management environment.

[0070] For further information, see Fig. 9 , Fig. 9 3 is a schematic diagram of the structure of the liquid cooling plate 30 provided in an embodiment of the present invention. In order to enhance the overall heat dissipation performance of the battery module, a groove 31 is designed on the side of the liquid cooling plate 30 close to the battery cell 10, and a thermal conductive adhesive layer 50 is filled in the groove 31. By increasing the contact area between the thermal conductive adhesive layer 50 and the liquid cooling plate 30, the heat transfer efficiency between the battery cell 10 and the liquid cooling plate 30 is significantly improved, thereby achieving a more efficient heat dissipation effect.

[0071] The grooves 31 of the liquid cooling plate 30 are usually designed as regular rectangles, strips or grids, and their depth and spacing can be flexibly adjusted according to the heat dissipation requirements. The grooves 31 are distributed on the side of the liquid cooling plate 30 close to the second end surface 112 of the battery cell 10, and the thermal conductive adhesive layer 50 is filled into the grooves 31, so that the inner wall of the grooves 31 of the liquid cooling plate 30 and the second end surface 112 of the battery cell 10 form a stable and efficient heat conduction path.

[0072] In this embodiment, compared with the traditional planar contact design, the groove 31 structure of the liquid cooling plate 30 effectively improves the heat exchange efficiency per unit area. Increasing the contact area not only improves the overall thermal conductivity, but also significantly reduces the interface thermal resistance, and minimizes the local air gap caused by slight surface unevenness or assembly errors.

[0073] In addition, the depth and shape of the grooves 31 can be individually adjusted according to the power density and thermal management requirements of the battery cell 10. For example, in areas with higher heat loads, the grooves 31 can be designed to be deeper and denser to provide stronger heat dissipation capabilities; while in areas with lower heat loads, the number or depth of the grooves 31 can be appropriately reduced to achieve the best balance between performance and material cost.

[0074] In some embodiments, see Fig.10 and Fig.11 , Fig.10is a side view of a battery module provided by an embodiment of the present invention, Fig.11 The embodiment of the present invention provides Fig.10 A cross-sectional view along the BB direction. A flow channel 32 is provided in the liquid cooling plate 30 and is equipped with a liquid inlet 33 and a liquid outlet 34 connected to the flow channel 32. The flow channel 32 includes a plurality of first flow channels 321 and a plurality of second flow channels 322. The first flow channels 321 and the second flow channels 322 are connected end to end in sequence and arranged alternately to form a highly integrated cooling circuit structure.

[0075] The plurality of first flow channels 321 and second flow channels 322 are arranged in a staggered manner in a "Z" shape or a "snake" shape, and the overall layout forms a continuous liquid circulation path. When the coolant enters the flow channel 32 system from the liquid inlet 33, it first passes through a first flow channel 321, and then sequentially enters the second flow channel 322 connected thereto, forming an alternating cycle. The first flow channels 321 and the second flow channels 322 in the entire fluid path are repeatedly connected alternately until they are finally discharged from the liquid outlet 34.

[0076] In this embodiment, the alternately connected flow channels 32 can effectively extend the flow path of the coolant in the liquid cooling plate 30, thereby increasing the heat exchange area with the inner wall of the liquid cooling plate 30. Under this layout of the flow channels 32, the coolant can flow evenly through the entire inner cavity area of ​​the liquid cooling plate 30, ensuring that each heated area of ​​the battery cell 10 can be cooled in time, avoiding the local overheating and cooling dead corner problems that may occur in the traditional linear flow channel 32 design.

[0077] The first flow channel 321 and the second flow channel 322 can be designed differently in shape, size and layout density to meet the heat dissipation requirements of different areas. The first flow channel 321 can be designed as a wider or deeper channel to adapt to the high flow rate of the coolant after entering the liquid cooling plate 30, ensuring that the coolant can quickly absorb the heat at the entry end. The second flow channel 322 can be designed as a narrower or shallower channel to slow down the flow rate of the coolant and prolong the contact time between the coolant and the inner wall of the flow channel 32, thereby improving the heat exchange efficiency.

[0078] An embodiment of the present invention further provides a battery pack, which includes the above-mentioned battery module.

[0079] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0080] It should also be noted that when an element is referred to as being "fixed on" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element at the same time. When an element is referred to as being "connected to" another element, it may be directly connected to the other element or may be indirectly connected to the other element through an intermediate element.

[0081] In addition, the descriptions of "first", "second", etc. in the present invention are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0082] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A battery module, characterized in that: include: A plurality of battery cells are arranged along the thickness direction thereof, wherein the battery cells have oppositely disposed end faces along the height direction thereof and oppositely disposed first side faces along the thickness direction thereof; A plurality of heat dissipation plates are sequentially arranged between the battery cells, the heat dissipation plates include a first heat dissipation portion and a second heat dissipation portion connected to each other, the first heat dissipation portion is attached to the first side surface, and the second heat dissipation portion is attached to the end surface; A liquid cooling plate is arranged on one side of the plurality of battery cells close to the end surface, and the liquid cooling plate is connected to the second heat dissipation part.

2. A battery module according to claim 1, characterized in that: The contact area between the first heat dissipation portion and the first side surface is S1, the contact area between the second heat dissipation portion and the end surface is S2, H1=S1 / S2, wherein 1.5≤H1≤3.

5.

3. A battery module according to claim 1, characterized in that: The battery cell also has a second side surface arranged opposite to each other along its length direction, and the heat dissipation plate also includes a third heat dissipation portion, which is interconnected with the first heat dissipation portion and the second heat dissipation portion, and the third heat dissipation portion is in contact with the second side surface, and the first side surface is larger than the second side surface.

4. A battery module according to claim 3, characterized in that: The contact area between the third heat dissipation portion and the second side surface is S3, H2=(S1+S3) / S2, wherein 1.5≤H2≤3.

5.

5. A battery module according to claim 1, characterized in that: The heat dissipation plate is provided with a heat dissipation cavity, which is in a vacuum state and filled with acetaldehyde.

6. A battery module according to claim 5, characterized in that: The heat dissipation plate further comprises a porous structure layer, which is formed by sintered copper powder and adheres to the inner wall of the heat dissipation cavity.

7. A battery module according to claim 1, characterized in that: The battery module also includes an adhesive adhesive, which is sandwiched between the heat dissipation plate and the battery cell.

8. A battery module according to any one of claims 1 to 7, characterized in that: The end surface comprises a first end surface and a second end surface which are arranged opposite to each other; The battery core further includes a pressure relief valve, which is disposed on the first end surface. The second heat dissipation portion is attached to the second end surface, and the liquid cooling plate is disposed on a side of the battery core close to the second end surface.

9. A battery module according to claim 8, characterized in that: The battery module also includes a thermally conductive adhesive layer, which is arranged on the second end surface. The opposite ends of the thermally conductive adhesive layer are respectively connected to the second heat dissipation parts of the adjacent heat dissipation plates, and the liquid cooling plate is connected to the second heat dissipation parts and the thermally conductive adhesive layer.

10. A battery module according to claim 9, characterized in that: A groove is formed on one side of the liquid cooling plate close to the battery core, and the thermal conductive adhesive layer fills the groove.

11. A battery module according to any one of claims 1 to 7, characterized in that: The liquid cooling plate is provided with a flow channel and a liquid inlet and a liquid outlet communicated with the flow channel; The flow channel includes a plurality of first flow channels and a plurality of second flow channels, the first flow channels and the second flow channels are connected end to end in sequence, and the first flow channels and the second flow channels are alternately arranged.

12. A battery pack, characterized in that: include: The battery module according to any one of claims 1 to 11.

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