battery pack

Abstract

This utility model belongs to the field of power battery technology and discloses a battery pack. Specifically, the battery pack includes a first liquid cooling plate, multiple cell groups spaced apart along a first direction, and multiple second liquid cooling plates extending along the aforementioned second direction. Each cell group includes multiple individual cells stacked along the second direction, which is perpendicular to the first direction. The first liquid cooling plate is disposed at the bottom of the multiple cell groups and serves to support the cell groups. The second bottom wall of the second liquid cooling plate communicates with the first liquid cooling plate. At least one of the two first sidewalls at both ends of each cell group along the first direction is attached to the second liquid cooling plate, so that each individual cell is heat-exchange connected to both the first and second liquid cooling plates. This battery pack can improve heat dissipation efficiency and cooling effect, ensure reliable and safe operation of individual cells, and also increase the energy density of the battery pack.

Description

Technical Field

[0001] This utility model relates to the field of power battery technology, and in particular to a battery pack. Background Technology

[0002] The driving range of a new energy vehicle depends primarily on the energy density of its battery system. To meet consumer demand for long driving range in new energy vehicles, battery systems are designed and developed with high energy density. However, high-energy-density battery systems generate and accumulate more heat during operation. If this heat cannot be dissipated in time to ensure the battery remains within a suitable temperature range, it can not only prevent the battery system from performing at its full potential but may also lead to safety accidents in severe cases.

[0003] In cylindrical battery systems, the traditional approach involves using liquid cooling plates and pipes to dissipate heat. The coolant flow path is: "Battery system side inlet pipe (inflow) — serpentine liquid cooling plate (passing through) — battery system side outlet pipe (outflow)." While widely used, this cooling method has several drawbacks. First, the coolant preferentially flows in and exchanges heat from the side of the battery system, resulting in a higher temperature in the center than on the sides. This leads to poor temperature uniformity within the system, impacting battery lifespan. Second, the side area requires space for the inlet and outlet pipes, resulting in low internal space utilization and negatively affecting overall energy density. Third, the liquid cooling plates are connected via corrugated pipe expansion joints, which have limited pressure resistance (approximately 2 MPa). Prolonged high-pressure operation poses a significant risk of failure, potentially causing coolant leakage and safety incidents.

[0004] Therefore, there is an urgent need to provide a new type of battery pack to solve the above-mentioned technical problems in the prior art. Utility Model Content

[0005] One objective of this invention is to provide a battery pack that can improve heat dissipation efficiency and cooling effect, ensure reliable and safe operation of individual battery cells, and also improve the energy density of the battery pack.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] The battery pack specifically includes a first liquid cooling plate, a plurality of cell groups spaced apart along a first direction, and a plurality of second liquid cooling plates extending along the aforementioned second direction. Each cell group includes a plurality of individual cells stacked along the second direction, which is perpendicular to the first direction. The first liquid cooling plate is disposed at the bottom of the plurality of cell groups and is used to support the cell groups. The second bottom wall of the second liquid cooling plate is connected to the first liquid cooling plate. At least one of the two first sidewalls at both ends of each cell group along the first direction is attached to the second liquid cooling plate, so that the individual cells are respectively connected to the first liquid cooling plate and the second liquid cooling plate for heat exchange.

[0008] Optionally, the first liquid cooling plate is provided with a first liquid cooling channel, the second liquid cooling plate is provided with a second liquid cooling channel, and either the first top wall of the first liquid cooling plate or the second bottom wall of the second liquid cooling plate is provided with a first liquid inlet connector, one end of the first liquid inlet connector being connected to the first liquid cooling channel and the other end being connected to the second liquid cooling channel; and / or either the first top wall of the first liquid cooling plate or the second bottom wall of the second liquid cooling plate is provided with a first liquid outlet connector, one end of the first liquid outlet connector being connected to the first liquid cooling channel and the other end being connected to the second liquid cooling channel.

[0009] Optionally, the first top wall of the first liquid cooling plate is provided with a plurality of first liquid inlet connectors and a plurality of first liquid outlet connectors, the plurality of first liquid inlet connectors being spaced apart along the first direction, the plurality of first liquid outlet connectors being spaced apart along the first direction, and the first liquid inlet connectors and the first liquid outlet connectors being spaced apart in the second direction.

[0010] Optionally, the first liquid cooling plate is provided with the first liquid outlet connector at both ends along the second direction, the first liquid inlet connector is disposed between two first liquid outlet connectors spaced apart along the second direction, and the two ends of the second liquid cooling plate along the second direction are connected one-to-one to the two first liquid outlet connectors spaced apart along the second direction.

[0011] Optionally, N first liquid inlets are spaced apart between the two first liquid outlets spaced apart along the second direction, and N first liquid inlets are connected to the middle of each second liquid cooling plate, where N is an integer greater than 1.

[0012] Optionally, each of the aforementioned battery cell groups is provided with a second liquid cooling plate at both ends along the first direction, and a second liquid cooling plate is sandwiched between two adjacent battery cell groups along the first direction.

[0013] Optionally, the aforementioned single battery cell is a cylindrical battery cell, and the second sidewalls of the second liquid cooling plate at both ends of the first direction are wavy, and the aforementioned single battery cell is adapted to the second sidewalls of the second liquid cooling plate at both ends of the first direction.

[0014] Optionally, multiple battery cell groups are stacked along the second direction, and each battery cell group is attached with a second liquid cooling plate. The second liquid cooling plates attached to two adjacent battery cell groups along the second direction are staggered in the first direction.

[0015] Optionally, the first top wall of the first liquid cooling plate is evenly spaced with a plurality of fixing grooves, and the individual battery cells are inserted into the fixing grooves one by one. Thermally conductive structural adhesive is sandwiched between the bottom wall of the individual battery cell and the fixing groove, and between the circumferential side wall of the individual battery cell and the second liquid cooling plate.

[0016] Optionally, the battery pack further includes a base plate, which is spaced apart on the side of the first liquid cooling plate away from the second liquid cooling plate. The bottom wall of the individual battery cell is provided with an explosion-proof valve. The inner bottom wall of the fixing groove penetrates the first liquid cooling plate to provide a pressure relief hole. A sealing sheet is provided in the pressure relief hole to block the pressure relief hole. The explosion-proof valve is provided corresponding to the pressure relief hole. When the individual battery cell is depressurized, the interior of the individual battery cell can communicate with the pressure relief cavity between the first liquid cooling plate and the base plate.

[0017] Beneficial effects:

[0018] The battery pack of this invention uses a first liquid cooling plate and a second liquid cooling plate to cool the cell assembly within the battery pack. The cell assembly consists of several individual cells stacked along a second direction. The first top wall of the first liquid cooling plate supports the individual cells, thereby cooling their bottoms. The second liquid cooling plate is attached to at least one end of the cell assembly along the first direction, thereby cooling the circumferential sidewalls of the individual cells, achieving complete cooling of the individual cells. This results in better cooling and heat dissipation, ensuring the safe and reliable operation of the individual cells within the battery pack. Simultaneously, the bottom of the second liquid cooling plate is directly connected to the first top wall of the first liquid cooling plate, eliminating the need for additional connecting pipes to connect the second liquid cooling plate to the battery pack's liquid cooling system. This simplifies the battery pack's structure and manufacturing process, increasing the space available for installing individual cells within the battery pack, improving the battery pack's energy density, and also increasing manufacturing efficiency and reducing manufacturing costs. This battery pack improves heat dissipation efficiency and cooling effect, ensuring reliable and safe operation of individual cells, and also increases the battery pack's energy density. Attached Figure Description

[0019] Figure 1This is an isometric view of the battery pack structure in Embodiment 1 of this utility model.

[0020] Figure 2 This is an isometric view of the battery pack structure in Embodiment 2 provided by the specific implementation of this utility model;

[0021] Figure 3 This is an isometric view of the battery pack structure in Embodiment 3 of this utility model.

[0022] Figure 4 This is an isometric view of the first and second liquid cooling plates after installation in Embodiment 1 of the present utility model.

[0023] Figure 5 This is an exploded view of the first liquid cooling plate and the second liquid cooling plate in Embodiment 1 provided by the specific implementation of this utility model;

[0024] Figure 6 This is an exploded view of the battery pack structure in Embodiment 1 of the present invention.

[0025] Figure 7 This is a cross-sectional view of a single battery cell and part of the first liquid cooling plate provided in a specific embodiment of this utility model.

[0026] In the picture:

[0027] 100. Battery cell assembly; 101. First sidewall; 110. Individual battery cell; 111. Explosion-proof valve; 112. Battery cell bottom wall; 120. Thermally conductive structural adhesive;

[0028] 200. First liquid cooling plate; 201. Liquid inlet manifold; 202. Liquid outlet manifold; 203. First liquid inlet connector; 204. First liquid outlet connector; 205. First liquid cooling channel; 206. First top wall; 210. Fixing groove; 211. Pressure relief hole; 212. Sealing plate; 220. Base plate; 221. Pressure relief cavity;

[0029] 300. Second liquid cooling plate; 301. Second liquid cooling channel; 302. Second bottom wall; 303. Second side wall; 310. Mounting protrusion. Detailed Implementation

[0030] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, not the entire structure.

[0031] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0032] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0033] In the description of this embodiment, the terms "upper," "lower," "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.

[0034] The first direction described in this embodiment is: Figure 1 The X direction shown is the length direction of the second liquid cooling plate 300; the second direction is... Figure 1 The Y direction shown is the thickness direction of the second liquid cooling plate 300. The first direction and the second direction are perpendicular to each other, and both the first direction and the second direction are perpendicular to the vertical direction.

[0035] like Figures 1 to 3As shown, the battery pack specifically includes a first liquid cooling plate 200, a plurality of cell groups 100 spaced apart along a first direction, and a plurality of second liquid cooling plates 300 extending along the aforementioned second direction. Each cell group 100 includes a plurality of individual cells 110 stacked along the second direction, which is perpendicular to the first direction. The first liquid cooling plate 200 is disposed at the bottom of the plurality of cell groups 100 and is used to support the cell groups 100. The second bottom wall 302 of the second liquid cooling plate 300 is connected to the first liquid cooling plate 200. At least one of the two first sidewalls 101 at both ends of each cell group 100 along the first direction is attached to the second liquid cooling plate 300, so that the individual cells 110 are respectively connected to the first liquid cooling plate 200 and the second liquid cooling plate 300 for heat exchange.

[0036] In this embodiment, the battery pack uses a first liquid cooling plate 200 and a second liquid cooling plate 300 to cool the cell assembly 100 within the battery pack. The cell assembly 100 consists of a plurality of individual cells 110 stacked along a second direction. The first top wall 206 of the first liquid cooling plate 200 supports the individual cells 110, thereby cooling the bottom of the individual cells 110. The second liquid cooling plate 300 is attached to at least one end of the first sidewall 101 of the cell assembly 100 along the first direction, thereby cooling the circumferential sidewall of the individual cells 110, thus achieving cooling of the individual cells 110. The complete cooling of the first liquid cooling plate 200 results in better cooling and heat dissipation, ensuring the safe and reliable operation of the individual battery cells 110 within the battery pack. Simultaneously, the bottom of the second liquid cooling plate 300 is directly connected to the first top wall 206 of the first liquid cooling plate 200, eliminating the need for additional connecting pipes to connect the second liquid cooling plate 300 to the battery pack's liquid cooling system. This simplifies the battery pack's structure and manufacturing process, thereby increasing the space within the battery pack for installing the individual battery cells 110, improving the battery pack's energy density, and also increasing manufacturing efficiency and reducing manufacturing costs. This battery pack improves heat dissipation efficiency and cooling effect, ensuring the reliable and safe operation of the individual battery cells 110, and also increases the battery pack's energy density.

[0037] In this embodiment, the single cell 110 is a large cylindrical battery with a diameter of 46mm, which will not be described in detail here.

[0038] The first top wall 206 of the first liquid cooling plate 200 is the outer wall of the first liquid cooling plate 200 along its own thickness direction that is close to the second liquid cooling plate 300, and the first top wall 206 corresponds to the bottom wall of the first liquid cooling plate 200; the second bottom wall 302 of the second liquid cooling plate 300 is the outer wall of the second liquid cooling plate 300 along its own height direction that is close to the first liquid cooling plate 200, and the second bottom wall 302 corresponds to the top wall of the second liquid cooling plate 300; wherein, the first top wall 206 and the second bottom wall 302 are arranged opposite to each other and abut against each other to achieve a fixed connection between the first liquid cooling plate 200 and the second liquid cooling plate 300.

[0039] Furthermore, a first liquid cooling channel is provided in the first liquid cooling plate 200, and a second liquid cooling channel is provided in the second liquid cooling plate 300. A first liquid inlet connector 203 is provided in either the first top wall 206 of the first liquid cooling plate 200 or the second bottom wall 302 of the second liquid cooling plate 300. One end of the first liquid inlet connector 203 is connected to the first liquid cooling channel, and the other end is connected to the second liquid cooling channel. And / or a first liquid outlet connector 204 is provided in either the first top wall 206 of the first liquid cooling plate 200 or the bottom of the second liquid cooling plate 300. One end of the first liquid outlet connector 204 is connected to the first liquid cooling channel, and the other end is connected to the second liquid cooling channel. In this embodiment, both the first inlet connector 203 and the first outlet connector 204 are pagoda connectors. A pagoda connector is a mechanical part used to connect two cylindrical parts, typically consisting of two parts: a large conical end and a small conical end. These two parts are joined together and secured with threads or other sealing devices. Specifically, in this embodiment, the two ends of the pagoda connector are fixed to the first liquid cooling plate 200 and the second liquid cooling plate 300 using an expansion joint. The pagoda connector mainly consists of a connector body, bolts, and a sealing ring. Its structure is simple and compact, easy to install, and suitable for various pipeline connection applications. The material of the pagoda connector is typically stainless steel, carbon steel, or copper, etc. The specific material selection depends on the corrosiveness, oxidizing properties, and other characteristics of the liquid or gas being transported. In this embodiment, the first inlet connector 203 and the first outlet connector 204 are made of stainless steel and are fixed to the alloy-material first liquid cooling plate 200 using a quick-connect method, thereby achieving a rapid connection between the first liquid cooling plate 200 and the second liquid cooling plate 300, while also ensuring higher connection stability.

[0040] It should be noted that, in order to improve the stability of the connection, it can be sealed and reinforced by applying thermally conductive structural adhesive 120 to the connection between the first liquid inlet connector 203 and the first liquid outlet connector 204 and the first liquid cooling plate 200 and the second liquid cooling plate 300, respectively. This will not be elaborated here.

[0041] Specifically, the first top wall 206 of the first liquid cooling plate 200 is provided with an inlet and an outlet at one end along the first direction. The inlet and outlet are connected to the inlet manifold 201 and the outlet manifold 202 respectively through CQC connectors (China Quality Certification Center). A CQC connector is a quick connector used for water pipe connection or water cooling system. It is usually made of metal or plastic and has various models such as straight head, elbow and tee, which are suitable for different installation requirements.

[0042] Preferably, the second liquid cooling plate 300 has a height of 80mm, a total thickness of 3.5mm, a wall thickness of 0.3mm, and the channel reinforcing ribs of the second liquid cooling channel have a thickness of 0.3mm. The second liquid cooling channel is serpentine, with each serpentine channel having the same cross-sectional dimensions, good flow uniformity, and a rounded rectangular shape, resulting in low flow resistance. It also possesses a certain mechanical strength to prevent deformation caused by squeezing the channel.

[0043] like Figure 4 and Figure 5 As shown, optionally, the first top wall 206 of the first liquid cooling plate 200 is provided with a plurality of first liquid inlet connectors 203 and a plurality of first liquid outlet connectors 204. The plurality of first liquid inlet connectors 203 are spaced apart along the first direction, and the plurality of first liquid outlet connectors 204 are spaced apart along the first direction, and the first liquid inlet connectors 203 and the first liquid outlet connectors 204 are spaced apart in the second direction. In this embodiment, by providing the first liquid inlet connectors 203 and the first liquid outlet connectors 204 on the first liquid cooling plate 200, the first liquid inlet connectors 203 and the second liquid outlet connectors can be easily installed. After installation, the second liquid cooling plate 300 can also be easily installed, improving installation efficiency.

[0044] In this embodiment, the first liquid cooling plate 200 is provided with first liquid outlet connectors 204 at both ends along the second direction, and the first liquid inlet connectors 203 are disposed between two first liquid outlet connectors 204 spaced apart along the second direction. The second liquid cooling plate 300 is connected one-to-one with the two first liquid outlet connectors 204 spaced apart along the second direction at both ends. Thus, after the coolant flows into the first liquid cooling plate 200, it flows from the middle part of the first liquid cooling plate 200 into the middle part of the second liquid cooling plate 300, then flows along the second direction to both ends of the second liquid cooling plate 300, and finally flows into the interior of the first liquid cooling plate 200. This achieves uniform cooling of the individual battery cells 110 stacked along the second direction, ensuring that the cooling effect of the individual battery cells 110 stacked along the second direction is consistent whether in the middle or at both ends, without temperature differences, resulting in better cooling and heat dissipation.

[0045] Optionally, N first liquid inlet connectors 203 are spaced apart between the two first liquid outlet connectors 204 arranged along the second direction, and each of the second liquid cooling plates 300 has N first liquid inlet connectors 203 connected to its middle portion, where N is an integer greater than 1. In this embodiment, N=3, that is, each second liquid cooling plate 300 introduces coolant through three first liquid inlet connectors 203, improving the uniformity of coolant flow and making the flow smoother.

[0046] like Figure 5 and Figure 6As shown, the first top wall 206 of the first liquid cooling plate 200 has a plurality of fixing grooves 210 evenly spaced. The individual battery cells 110 are inserted into the fixing grooves 210 one by one. Thermally conductive structural adhesive 120 is sandwiched between the bottom wall 112 of the individual battery cell 110 and the fixing grooves 210, and between the circumferential sidewall of the individual battery cell 110 and the second liquid cooling plate 300. The thermally conductive structural adhesive 120 fixes and seals the connection between the first liquid cooling plate 200 and the individual battery cell 110, and also fixes the individual battery cell 110 and the second liquid cooling plate 300. This not only enhances the heat exchange efficiency, but also improves the connection reliability between the first liquid cooling plate 200, the second liquid cooling plate 300 and the individual battery cell 110.

[0047] Specifically, the thermally conductive structural adhesive 120 is formed by spraying an 8mm to 10mm thick layer of liquid adhesive onto the single battery cell 110 after it is placed on the first liquid cooling plate 200, and then cooling and solidifying it. This will not be elaborated further here.

[0048] In this embodiment, the thermally conductive structural adhesive 120 between the individual battery cell 110 and the fixing groove 210 is annular, and the thermally conductive structural adhesive 120 between the individual battery cell 110 and the second liquid cooling plate 300 is sheet-like. This is determined by the shapes of the individual battery cell 110, the fixing groove 210 and the second liquid cooling plate 300, which will not be elaborated here.

[0049] Optionally, the battery pack further includes a base plate 220, which is spaced apart on the side of the first liquid cooling plate 200 away from the second liquid cooling plate 300. The bottom wall 112 of the individual battery cell 110 is provided with an explosion-proof valve 111. The inner bottom wall of the fixing groove 210 penetrates the first liquid cooling plate 200 and is provided with a pressure relief hole 211. A sealing sheet 212 is provided in the pressure relief hole 211 to block the pressure relief hole 211. The explosion-proof valve 111 is provided corresponding to the pressure relief hole 211. When the individual battery cell 110 is depressurized, the interior of the individual battery cell 110 can be connected to the pressure relief cavity 221 between the first liquid cooling plate 200 and the base plate 220. The dimensions of the fixing groove 210 match the bottom dimensions of the individual battery cell 110. The diameter of the pressure relief hole 211 is smaller than the diameter of the individual battery cell 110 but larger than the diameter of the explosion-proof valve 111, so that the fixing groove 210 can support and fix the individual battery cell 110. This ensures that the explosion-proof valve 111 can open normally and relieve pressure when the individual battery cell 110 experiences thermal runaway. The high-temperature and high-pressure gas generated by thermal runaway breaks through the sealing sheet 212 and is introduced into the pressure relief cavity 221 between the first liquid cooling plate 200 and the bottom plate 220, and finally discharged to the outside of the battery box of the battery pack, thus realizing the explosion-proof pressure relief of the individual battery cell 110. The first liquid cooling plate 200 can also cool down the high-temperature gas emitted during thermal runaway, reducing the probability of heat spread and making it more reliable.

[0050] Furthermore, the positive and negative terminals of the individual battery cell 110 are both located at the top, away from the first liquid cooling plate 200, ensuring that the coolant is kept away from the positive and negative terminals of the individual battery cell 110, thus improving the safety of the battery pack.

[0051] In this embodiment, the surfaces of the first liquid cooling plate 200 and the second liquid cooling plate 300 are coated with an insulating high-temperature resistant coating to achieve insulation between the individual battery cell 110 and the first liquid cooling plate 200 and the second liquid cooling plate 300. At the same time, it prevents the coating from being damaged by high temperature after the individual battery cell 110 thermal runaway, and prevents thermal runaway from turning into thermal propagation and thermal diffusion, thereby improving the safety and reliability of the battery pack. Further details are omitted here.

[0052] Example 1

[0053] like Figure 1 As shown, each of the aforementioned cell groups 100 is provided with a second liquid cooling plate 300 at both ends along the first direction, and a second liquid cooling plate 300 is sandwiched between two adjacent cell groups 100 along the first direction. This achieves three-sided cooling of a single cell 110, resulting in better cooling effect and ensuring higher temperature consistency among the individual cells 110. However, this method is more expensive and will not be elaborated further here.

[0054] Optionally, the individual battery cell 110 is a cylindrical cell, and the second sidewalls 303 of the second liquid cooling plate 300 along both ends of the first direction are wavy, with the individual battery cell 110 and the second sidewalls 303 of the second liquid cooling plate 300 along both ends of the first direction being compatible. This configuration of the second liquid cooling plate 300 increases the contact area with the individual battery cell 110, improves the connection reliability between the individual battery cell 110 and the second liquid cooling plate 300, enhances the cooling effect of the second liquid cooling plate 300 on the individual battery cell 110, and also reduces the dimensions of the individual battery cell 110 and the second liquid cooling plate 300 along the second direction after assembly, thereby increasing the energy density of the battery pack.

[0055] like Figure 6 As shown, the second liquid cooling plate 300 has a wave-like second sidewall 303 at both ends of the first direction, and has a number of mounting protrusions 310. The mounting protrusions 310 extend vertically and are provided corresponding to the first liquid inlet connector 203, so as to facilitate the insertion and fixing of the first liquid inlet connector 203 and the second liquid cooling plate 300. The mounting protrusions 310 are located between two adjacent single cells 110, that is, on the crest of the second liquid cooling plate 300. The mounting protrusions 310 have a hollow inner cavity, which communicates with the second liquid cooling channel of the second liquid cooling plate 300. Thus, the second liquid cooling plate 300 and the first liquid cooling plate 200 can be connected.

[0056] Example 2

[0057] like Figure 2As shown, the difference between this second embodiment and the first embodiment is that each cell group 100 is only attached to one second liquid cooling plate 300, which can save materials, reduce costs, reduce production process steps, and improve manufacturing efficiency, but the heat dissipation effect is poor, and the temperature uniformity of the individual cells 110 is poor, which will not be elaborated here.

[0058] Example 3

[0059] like Figure 3 The difference between this second embodiment and the first embodiment is that multiple battery cell groups 100 are stacked along the second direction, and each battery cell group 100 is attached with a second liquid cooling plate 300. The second liquid cooling plates 300 attached to two adjacent battery cell groups 100 along the second direction are staggered in the first direction. This allows for single-sided cooling of the circumferential sidewall of each individual battery cell 110. Compared to the first embodiment, the third embodiment has lower cost but poorer heat dissipation and temperature uniformity. However, compared to the second embodiment, the individual battery cells 110 in this third embodiment have higher temperature uniformity, but the structure is more complex and the cost is higher, which will not be elaborated further here.

[0060] This embodiment also provides a battery pack manufacturing method, which is used to manufacture a battery pack as described in any of the above schemes, including the following steps: S1, manufacturing the first liquid cooling plate 200 and the second liquid cooling plate 300; S2, connecting the second bottom wall 302 of the plurality of the second liquid cooling plates 300 to the first top wall 206 of the first liquid cooling plate 200, wherein the second liquid cooling plates 300 extend along a second direction; S3, placing individual battery cells 110 on the first top wall 206 of the first liquid cooling plate 200, such that when the individual battery cells 110 are stacked along the second direction to form a battery cell group 100, at least one of the first sidewalls 101 at both ends of the battery cell group 100 along the first direction is attached to the second liquid cooling plate 300, and each individual battery cell 110 is heat-exchange connected to the first liquid cooling plate 200 and the second liquid cooling plate 300.

[0061] The battery pack manufactured by the method in this embodiment can cool the circumferential sidewalls and bottom of the individual battery cell 110, achieving complete cooling of the individual battery cell 110. Its cooling and heat dissipation effects are better, ensuring the safe and reliable operation of the individual battery cell 110 in the battery pack. At the same time, the bottom of the second liquid cooling plate 300 is directly connected to the first top wall 206 of the first liquid cooling plate 200, eliminating the need for additional connecting pipes to connect the second liquid cooling plate 300 to the liquid cooling system of the battery pack. This simplifies the structure of the battery pack, simplifies the production process steps, thereby increasing the space inside the battery pack for installing the individual battery cell 110, improving the energy density of the battery pack, and also improving manufacturing efficiency and reducing manufacturing costs.

[0062] After assembling the first liquid cooling plate 200, the second liquid cooling plate 300, and the cell assembly 100, it is necessary to spray and fill the gap between the first liquid cooling plate 200 and the cell assembly 100 with a liquid adhesive of 8mm to 10mm. After cooling and solidification, a thermally conductive structural adhesive 120 is formed, which is used to fix the individual cell 110 to the first liquid cooling plate 200 and the second liquid cooling plate 300, and at the same time improve the heat exchange efficiency. This will not be elaborated here.

[0063] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the present utility model, and are not intended to limit the implementation of the present utility model. Those skilled in the art can make various obvious changes, readjustments, and substitutions without departing from the protection scope of this utility model. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.

Claims

1. A battery pack, characterized by, include: Multiple battery cell groups (100) are spaced apart along a first direction, each battery cell group (100) comprising multiple individual battery cells (110) stacked along a second direction perpendicular to the first direction; A first liquid cooling plate (200) is disposed at the bottom of the plurality of battery cell groups (100) and is used to support the battery cell groups (100); Multiple second liquid cooling plates (300) are arranged extending along the second direction. The second bottom wall (302) of the second liquid cooling plate (300) is connected to the first liquid cooling plate (200). At least one of the two first sidewalls (101) at both ends of each cell group (100) along the first direction is attached to the second liquid cooling plate (300) so that the individual cell (110) is heat exchanged with the first liquid cooling plate (200) and the second liquid cooling plate (300) respectively.

2. The battery pack of claim 1, wherein, The first liquid cooling plate (200) is provided with a first liquid cooling channel, and the second liquid cooling plate (300) is provided with a second liquid cooling channel. Either the first top wall (206) of the first liquid cooling plate (200) or the second bottom wall (302) of the second liquid cooling plate (300) is provided with a first liquid inlet connector (203). One end of the first liquid inlet connector (203) is connected to the first liquid cooling channel, and the other end is connected to the second liquid cooling channel. A first liquid outlet connector (204) is provided on either the first top wall (206) of the first liquid cooling plate (200) or the second bottom wall (302) of the second liquid cooling plate (300), with one end of the first liquid outlet connector (204) connected to the first liquid cooling channel and the other end connected to the second liquid cooling channel.

3. The battery pack of claim 2, wherein, The first top wall (206) of the first liquid cooling plate (200) is provided with a plurality of first liquid inlet connectors (203) and a plurality of first liquid outlet connectors (204). The plurality of first liquid inlet connectors (203) are spaced apart along the first direction, and the plurality of first liquid outlet connectors (204) are spaced apart along the first direction. The first liquid inlet connectors (203) and the first liquid outlet connectors (204) are spaced apart in the second direction.

4. The battery pack of claim 3, wherein, The first liquid cooling plate (200) is provided with the first liquid outlet connector (204) at both ends along the second direction, the first liquid inlet connector (203) is provided between the two first liquid outlet connectors (204) spaced apart along the second direction, and the second liquid cooling plate (300) is connected one-to-one with the two first liquid outlet connectors (204) spaced apart along the second direction at both ends.

5. The battery pack of claim 4, wherein, N first liquid inlet connectors (203) are spaced apart between two first liquid outlet connectors (204) spaced apart along the second direction, and N first liquid inlet connectors (203) are connected to the middle of each second liquid cooling plate (300), where N is an integer greater than 1.

6. The battery pack of any one of claims 1-5, wherein, Each of the battery cell groups (100) is provided with a second liquid cooling plate (300) at both ends along the first direction, and a second liquid cooling plate (300) is sandwiched between two adjacent battery cell groups (100) along the first direction.

7. The battery pack of claim 6, wherein, The single battery cell (110) is a cylindrical battery cell, and the second sidewall (303) of the second liquid cooling plate (300) along both ends of the first direction is wavy. The single battery cell (110) is adapted to the second sidewall (303) of the second liquid cooling plate (300) along both ends of the first direction.

8. The battery pack of claim 3, wherein, Multiple battery cell groups (100) are stacked along the second direction. Each battery cell group (100) is attached with a second liquid cooling plate (300). The second liquid cooling plates (300) attached to two adjacent battery cell groups (100) along the second direction are staggered in the first direction.

9. The battery pack of claim 1, wherein, The first top wall (206) of the first liquid cooling plate (200) is evenly spaced with a plurality of fixing grooves (210), and the individual battery cells (110) are inserted into the fixing grooves (210) one by one. Thermally conductive structural adhesive (120) is sandwiched between the bottom wall (112) of the individual battery cell (110) and the fixing groove (210), and between the circumferential side wall of the individual battery cell (110) and the second liquid cooling plate (300).

10. The battery pack of claim 9, wherein, The battery pack also includes a base plate (220), which is spaced apart on the side of the first liquid cooling plate (200) away from the second liquid cooling plate (300). The bottom wall (112) of the individual battery cell (110) is provided with an explosion-proof valve (111). The inner bottom wall of the fixing groove (210) penetrates the first liquid cooling plate (200) and is provided with a pressure relief hole (211). A sealing sheet (212) is provided in the pressure relief hole (211) to block the pressure relief hole (211). The explosion-proof valve (111) is provided corresponding to the pressure relief hole (211). When the individual battery cell (110) is depressurized, the interior of the individual battery cell (110) can be connected to the pressure relief cavity (221) between the first liquid cooling plate (200) and the base plate (220).

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