Battery module assembly, battery pack and vehicle

Abstract

The invention relates to a battery module assembly, a battery pack and a vehicle. The battery module assembly comprises a battery cell and a first liquid cooling plate, the battery cell is provided with a pole and an anti-explosion valve which are located on the same end face in the height direction of the battery cell, the first liquid cooling plate is attached to the upper portion of the pole in the height direction of the battery cell, and the projection of the first liquid cooling plate and the projection of the anti-explosion valve in the height direction of the battery cell are not overlapped; and at least part of the first liquid cooling plate is located in the spraying range of the anti-explosion valve. According to the battery module assembly disclosed by the invention, the out-of-control battery cells are cooled by using the cooling medium released by the first liquid cooling plate, and meanwhile, the interference of the first liquid cooling plate on the opening of the anti-explosion valve and sprayed high-temperature substances is avoided, so that heat spreading is effectively inhibited.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS:

[0002] This application claims the priority of the Chinese patent application filed with the China Patent Office on December 7, 2023, with application number 202311677004.9 and application name “Battery module assembly, battery pack and vehicle”, all contents of which are incorporated by reference in the application. Technical Field

[0003] The present invention belongs to the technical field of batteries, and in particular relates to a battery module assembly, a battery pack and a vehicle. Background Art

[0004] Lithium-ion power batteries have become the mainstream of automotive power batteries in the current new energy industry. They have the advantages of high energy density and long cycle life. However, when power batteries have over-discharge, over-charge, over-temperature, or other internal quality problems, there is a risk of thermal runaway.

[0005] In the related art, a spray device is generally arranged directly above the explosion-proof valve. When thermal runaway occurs in the battery cell, the explosion-proof valve will spray high-temperature substances toward the spray device. The spray device melts through and releases cooling medium into the interior of the explosion-proof valve to cool down the battery cell, thereby suppressing the spread of heat from the runaway battery cell to the adjacent battery cells.

[0006] However, installing a spray device directly above the explosion-proof valve will hinder the opening and exhaust of the explosion-proof valve and cause the ejected material to accumulate between the battery cell and the spray device, which will not only affect the cooling effect of the cooling medium released by the spray device on the battery cell, but also cause the internal pressure of the battery cell to increase, and there is a risk of failure of the battery cell structure. Summary of the invention

[0007] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0008] To this end, an embodiment of the present invention provides a battery module assembly that can effectively cope with the heat spread of a runaway battery cell.

[0009] An embodiment of the present invention further provides a battery pack.

[0010] An embodiment of the present invention provides a vehicle.

[0011] A battery module assembly according to an embodiment of the present invention includes:

[0012] A battery cell, wherein the battery cell has a pole and an explosion-proof valve located on the same end surface in a height direction of the battery cell;

[0013] A first liquid cooling plate, wherein the first liquid cooling plate is attached above the pole along the height direction of the battery cell;

[0014] The projections of the first liquid cooling plate and the explosion-proof valve along the height direction of the battery core do not overlap, and at least a portion of the first liquid cooling plate is located within the spraying range of the explosion-proof valve.

[0015] In some embodiments, the first liquid cooling plate has a weak area, and the weak area is located within the spray range of the explosion-proof valve;

[0016] And / or, the first liquid cooling plate is made of a composite material.

[0017] In some embodiments, there is a first offset distance between the projection of the first liquid cooling plate and the explosion-proof valve along the height direction of the battery core, and the first offset distance is 0 to 30 mm;

[0018] And / or, the first liquid cooling plate and the explosion-proof valve have a second offset distance in a height direction of the battery core, and the second offset distance is 0 to 20 mm;

[0019] And / or, the melting point of the meltable portion of the first liquid cooling plate is less than or equal to 400°C.

[0020] In some embodiments, the wall thickness of the meltable portion of the first liquid cooling plate is 0.1 mm to 2 mm; and / or

[0021] The thermal conductivity of the first liquid cooling plate is greater than or equal to 0.5 W / m·K.

[0022] In some embodiments, the number of the battery cells is multiple, and the multiple battery cells are arranged in an array to form a battery module, the battery module includes at least one battery group arranged along a first direction, the first liquid cooling plate extends along the first direction, and the length of the first liquid cooling plate in the first direction is greater than or equal to the length of the battery group in the first direction;

[0023] Wherein, the first direction is perpendicular to the height direction of the battery cell.

[0024] In some embodiments, the first direction is the length direction of the battery cell, two first liquid cooling plates are attached above one of the poles, the two first liquid cooling plates are arranged at intervals along the width direction of the battery cell, and the explosion-proof valve is located between the two first liquid cooling plates;

[0025] Alternatively, the first direction is the width direction of the battery cell, and one of the first liquid cooling plates is attached above one of the poles.

[0026] In some embodiments, a bar plate is further included, wherein the bar plate is connected to the pole, and the first liquid cooling plate is attached to the bar plate.

[0027] In some embodiments, the first liquid cooling plate is connected to the pole via a heat conducting layer.

[0028] In some embodiments, a second liquid cooling plate is further included, wherein the second liquid cooling plate is disposed in close contact with the battery cell, and the second liquid cooling plate and the first liquid cooling plate are disposed opposite to each other in a height direction of the battery cell.

[0029] A battery pack according to an embodiment of the present invention comprises a battery module assembly as described in any one of the above embodiments.

[0030] The vehicle according to the embodiment of the present invention comprises a battery module assembly as described in any one of the above embodiments, or a battery pack as described in the above embodiments.

[0031] The battery cell module assembly in the embodiment of the present invention arranges the first liquid cooling plate on the pole of the battery cell, and makes the projections of the first liquid cooling plate and the explosion-proof valve in the height direction of the battery cell not overlap, that is, the arrangement is completely offset, so as to make full use of the space in the height direction of the battery cell, and reasonably plan the relative positions of the first liquid cooling plate and the explosion-proof valve of the battery cell. When the battery cell has thermal runaway, the high-temperature material inside the battery cell can be sprayed out from the explosion-proof valve and melt through the part of the first liquid cooling plate located within the spraying range of the explosion-proof valve, so that the cooling medium in the first liquid cooling plate can be sprayed toward the explosion-proof valve and the surrounding area, and then the cooling medium entering the inside of the runaway battery cell through the explosion-proof valve is used to cool the inside of the runaway battery cell. The first liquid cooling plate in the embodiment of the present invention can also reduce the need for explosion-proof valves. The opening of the explosion valve and the interference caused by the ejected high-temperature material avoid the risk of increased internal pressure of the battery cell and failure of the battery cell structure due to the accumulation of high-temperature materials near the explosion-proof valve, so that the cooling medium released by the first liquid cooling plate can more easily flow into the inside of the out-of-control battery cell, and the cooling effect on the out-of-control battery cell is better, thereby suppressing the spread of heat. In addition, the heat generated by the battery cell can be transferred to the first liquid cooling plate through the pole, and dissipated promptly and quickly through the cooling medium in the first liquid cooling plate, thereby improving the overall cooling capacity of the first liquid cooling plate for the battery module assembly, preventing the accumulation of heat near the pole and causing the risk of thermal runaway of the battery cell due to local excessive temperature, which is suitable for fast-charging batteries, thereby helping to improve the fast-charging capability and safety of use of the battery module assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a three-dimensional diagram of a battery module assembly according to an embodiment of the present invention.

[0033] Figure 2 It is a three-dimensional diagram of a battery module according to an embodiment of the present invention.

[0034] Figure 3 It is a front view of a battery module assembly according to an embodiment of the present invention.

[0035] Figure 4is a three-dimensional diagram of a battery pack according to an embodiment of the present invention.

[0036] Figure 5 It is a three-dimensional diagram of the battery module and the battery plate according to an embodiment of the present invention.

[0037] Figure 6 It is a front view of a battery module assembly according to another embodiment of the present invention.

[0038] Figure 7 It is a three-dimensional diagram of a battery module assembly according to another embodiment of the present invention.

[0039] Figure 8 4 is a three-dimensional diagram of a battery cell according to an embodiment of the present invention.

[0040] Fig. 9 It is a front view of a battery module assembly according to another embodiment of the present invention.

[0041] Fig.10 It is a three-dimensional diagram of the cooperation between the first liquid cooling plate and the second liquid cooling plate according to an embodiment of the present invention.

[0042] Fig.11 is a three-dimensional diagram of a first liquid cooling plate according to an embodiment of the present invention.

[0043] Fig.12 is a three-dimensional diagram of a second liquid cooling plate according to an embodiment of the present invention.

[0044] Fig.13 is a cross-sectional view of a second liquid cooling plate according to an embodiment of the present invention.

[0045] Fig.14 is a cross-sectional view of a first liquid cooling plate according to an embodiment of the present invention.

[0046] Reference numerals:

[0047] 1000, battery pack;

[0048] 100. battery module assembly; 200. housing;

[0049] 1. Battery module; 11. Battery cell; 111. Terminal column; 112. Shoulder; 113. Explosion-proof valve;

[0050] 2. Pieces;

[0051] 3. first liquid cooling plate; 31. liquid cooling part; 311. first cooling channel; 312. heat dissipation surface;

[0052] 32. Overlap edge;

[0053] 4. Second liquid cooling plate; 41. Second cooling channel; 42. Heat exchange panel; 43. Channel panel;

[0054] 51. Liquid inlet pipe; 52. Liquid outlet pipe. DETAILED DESCRIPTION

[0055] Embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0056] In the related art, a spray device is generally arranged on the top of the explosion-proof valve, and the projections of the spray device and the explosion-proof valve in the height direction of the battery cell are overlapped. When thermal runaway occurs in the battery cell, the leakage port of the spray device is opened by active opening or passive melting through, thereby releasing the cooling medium in the spray device to the explosion-proof valve of the runaway battery cell, cooling the runaway battery cell and the adjacent battery cells, thereby suppressing the heat spread process from the runaway battery cell to the adjacent battery cells.

[0057] However, the solutions in the related art have the following defects:

[0058] 1. The spray device is facing the explosion-proof valve of the out-of-control battery cell. When the distance between the spray device and the explosion-proof valve in the height direction of the battery cell is ≤8mm, the spray device will affect the exhaust space of the explosion-proof valve of the battery cell, which will cause the erupted high-temperature material to accumulate between the spray device and the explosion-proof valve of the battery cell. The internal pressure of the battery cell increases, and the battery cell structure has a greater risk of failure. In addition, the cooling medium sprayed by the spray device cannot enter the interior of the battery cell, and the cooling effect is poor.

[0059] 2. The spray device is facing the explosion-proof valve of the out-of-control battery cell. When the distance between the spray device and the explosion-proof valve in the height direction of the battery cell is ≤5mm, the spray device will hinder the opening of the explosion-proof valve.

[0060] 3. If the above two defects are avoided through reasonable distance design, the distance between the spray device and the battery cell explosion-proof valve in the height direction of the battery cell will be too large (greater than 8mm), which will greatly reduce the space integration efficiency of the battery pack.

[0061] The inventors have discovered that staggering the projections of the spray device and the explosion-proof valve in the height direction of the battery cell can solve the above three problems and defects. However, since the explosion-proof valve sprays high-temperature substances along the height direction of the battery cell, when the projections of the spray device and the explosion-proof valve in the height direction of the battery cell are staggered, the first liquid cooling plate may not be directly touched by the high-temperature substance, and may thus not be melted through. This potential problem cannot be effectively solved in the relevant technology.

[0062] It is generally believed in the industry that arranging the spray device and the explosion-proof valve opposite each other in the height direction of the battery cell can ensure that the spray device can be melted through, and it is subjectively believed that when the projections of the spray device and the explosion-proof valve in the height direction of the battery cell do not overlap, the spray device cannot be guaranteed to be melted through. As a result, the solution of staggering the projections of the spray device and the explosion-proof valve in the height direction of the battery cell has been ignored, and no further research has been conducted on the staggered arrangement solution.

[0063] In response to the inventor's findings and subjective biases in the industry, the inventor conducted further research and, by testing the positional relationship between the explosion-proof valve and the first liquid cooling plate, confirmed the broad spray range of the explosion-proof valve when the battery cell is under thermal runaway. The area where the high-temperature material actually passes and the area where the high-temperature material can effectively melt through at least part of the first spray device by means of thermal radiation, heat conduction, thermal convection, etc. are all determined as the spray range of the explosion-proof valve. When at least part of the spray device is arranged within the spray range, it can be ensured that the high-temperature material sprayed from the explosion-proof valve can melt through part of the spray device by the combined action of one or more of direct contact, thermal radiation, heat conduction, thermal convection, etc.

[0064] Based on the above research findings, the spray device and the explosion-proof valve are staggered in the height direction of the battery cell, and at least part of the spray device is arranged within the spray range of the explosion-proof valve. When a battery cell has thermal runaway, the spray device can be melted through by the high-temperature material sprayed by the explosion-proof valve, causing the cooling medium in the spray device to leak from the melted-through position to the vicinity of the runaway battery cell. Since there is no accumulation of high-temperature material at the explosion-proof valve, the cooling medium can more easily enter the battery cell, thereby achieving a better effect of cooling the runaway battery cell and its adjacent battery cells, and can more effectively suppress the progress of thermal runaway.

[0065] The inventors also found that in order to improve the thermal management performance of the battery in the related art, a cooling device is set on the surface of the pole and its tab, and the heat generated by the pole and its tab is quickly discharged through the circulation of the cooling medium to achieve cooling of the battery cell. When the battery cell has thermal runaway, the cooling device can also quickly take away the heat of the thermal runaway of the battery cell, thereby cooling the runaway battery cell and the adjacent battery cell. However, the cooling device on the surface of the battery cell pole and its tab is made of metal material (such as aluminum alloy, etc.). In the event of thermal runaway, the cooling device can only transfer heat to the battery cell through heat conduction, and high-temperature materials cannot melt through the cooling device. When the coolant water pump does not work, such as when the vehicle's 12V power supply is damaged or the water pump is damaged after a collision, the heat cannot be taken away by the circulation of the coolant, and the spread of the thermal runaway of the battery cell cannot be effectively suppressed.

[0066] Based on the problems and defects existing in the cooling device in the related technology, the inventors conducted research and found that after the spray device is attached to the pole, under normal operating conditions, the spray device can perform thermal management of the battery cell pole, adjust the battery cell temperature, and improve the thermal management performance of the battery cell. Thus, the spray device has both the advantages of spraying cooling medium to suppress heat spread when the battery cell has thermal runaway and the advantage of improving the thermal management performance of the battery cell under normal operating conditions.

[0067] Please refer to the following Figure 1-Figure 14 , describing a battery module assembly 100, a battery pack 1000 and a vehicle according to an embodiment of the present invention.

[0068] like Figure 1-Figure 3 As shown, a battery module assembly 100 according to an embodiment of the present invention includes a battery cell 11 and a first liquid cooling plate 3, the battery cell 11 has a pole 111 and an explosion-proof valve 113 located on the same end face in the height direction of the battery cell 11, the first liquid cooling plate 3 is attached above the pole 111 along the height direction of the battery cell 11, the projections of the first liquid cooling plate 3 and the explosion-proof valve 113 along the height direction of the battery cell 11 do not overlap, and at least a portion of the first liquid cooling plate 3 is located within the spray range of the explosion-proof valve 113.

[0069] It should be understood that the pole 111 and the explosion-proof valve 113 are integrated on the same end face of the battery cell 11, and the first liquid cooling plate is connected to the pole, so as to facilitate the reasonable layout of the relative position relationship of the pole 111, the first liquid cooling plate 3 and the explosion-proof valve 113, so that the first liquid cooling plate 3 can not only suppress the process of thermal runaway of the battery cell when thermal runaway occurs in the battery cell 11, but also cool the pole 111 under normal operating conditions, thereby improving the thermal management performance of the battery cell.

[0070] When the battery cell 11 has thermal runaway due to over-discharge, over-charge, over-temperature, or other internal quality problems, the high-temperature material inside the battery cell 11 will break through the explosion-proof valve 113 and erupt. The high-temperature material will melt through the portion of the first liquid cooling plate 3 located in the spraying range of the explosion-proof valve 113 in a short time. The cooling medium in the first liquid cooling plate 3 will spray toward the vicinity of the explosion-proof valve 113 and enter the battery cell 11, thereby reducing the temperature of the battery cell 11 and suppressing the spread of heat.

[0071] In the embodiment of the present invention, since the projections of the first liquid cooling plate 3 and the explosion-proof valve 113 in the height direction of the battery cell 11 do not overlap, the spray path of the sprayed high-temperature substance will not be interfered with, and the high-temperature substance will not be blocked and change the spray direction, causing the adjacent battery cell 11 to be directly impacted by the high-temperature substance. It can also prevent the high-temperature substance from accumulating between the battery cell 11 and the first liquid cooling plate 3, resulting in the cooling medium being unable to flow into the battery cell 11. The arrangement position of the first liquid cooling plate 3 and the explosion-proof valve 113 in the embodiment of the present invention can make the high-temperature substance be sprayed out in time, and release the pressure inside the battery cell 11, and also facilitate the cooling medium to flow into the battery cell 11 to achieve cooling, thereby improving the cooling effect.

[0072] The spraying range of the explosion-proof valve 113 in the embodiment of the present invention includes but is not limited to the area where the high-temperature material actually passes, and the area where the high-temperature material can effectively melt through at least part of the first liquid cooling plate 3 through heat radiation, heat conduction, heat convection, etc.

[0073] For example, when thermal runaway occurs in the battery cell 11, the explosion-proof valve 113 opens, and the high-temperature material sprayed from the explosion-proof valve 113 will be approximately inverted cone shape. At this time, the approximately inverted cone-shaped area actually passed by the high-temperature material is the spray range of the explosion-proof valve 113. At the same time, the heat radiation area close to the inverted cone area and capable of reaching a temperature that can melt through the first liquid cooling plate 3 is also the spray range of the explosion-proof valve 113.

[0074] Although the projections of the first liquid cooling plate 3 and the explosion-proof valve 113 in the height direction of the battery cell 11 do not overlap, a portion of the first liquid cooling plate 3 close to the explosion-proof valve 113 is within the spray range, and the portion of the first liquid cooling plate 3 within the spray range can be melted through, and the cooling medium in the first liquid cooling plate 3 will flow to the first weak area 113, and then enter the inside of the out-of-control battery cell 11.

[0075] The first liquid cooling plate 3 in the embodiment of the present invention has a width dimension, and at least a portion of the first liquid cooling plate 3 is located within the spray range of the explosion-proof valve 113. It should be understood that the first liquid cooling plate 3 is in its own width direction (that is, Figure 1 ) is partially or entirely located within the spray range of the explosion-proof valve 113. Figure 1 As shown, Figure 1 The portion A within the dotted line range shown in FIG. 1 is the portion of the first liquid cooling plate 3 located within the spraying range of the explosion-proof valve 113. Figure 1 As shown, changing the first liquid cooling plate 3 in Figure 1 The position in the length direction shown in , the size of the portion A within the dotted line range can be adjusted, thereby adjusting the size of the portion of the first liquid cooling plate 3 located within the spray range of the explosion-proof valve 113. For another example, the width of the first liquid cooling plate 3 is relatively small, and all portions of the first liquid cooling plate 3 in its width direction are located within the spray range of the explosion-proof valve 113.

[0076] In the embodiment of the present invention, the length direction shown in the drawings is the length direction of the battery cell, the width direction is the width direction of the battery cell, and the height direction is the height direction of the battery cell.

[0077] in addition, Figure 1 The portion A shown in the figure may be an approximately fan-shaped region, or the portion A may be an approximately rectangular region.

[0078] Figure 1 The first liquid cooling plates 3 are disposed on both poles 111 of the battery cell 11 shown in the figure, and each of the first liquid cooling plates 3 has a partial portion located within the spraying range of the explosion-proof valve 113 .

[0079] In addition, the cooling medium sprayed out after the first liquid cooling plate 3 is melted through can form a spray area centered on the explosion-proof valve 113, which not only performs targeted cooling of the explosion-proof valve 113 of the out-of-control battery cell 11, but also can form an effective wrap-around spray on the surrounding area of ​​the explosion-proof valve 113. Part of the cooling medium can also pass through the explosion-proof valve 113 into the battery cell 11, cool the interior of the battery cell, and improve the effect of suppressing the spread of heat.

[0080] When the battery cell 11 has thermal runaway, the high-temperature material inside the battery cell 11 can be ejected from the explosion-proof valve 113 and melt through the portion of the first liquid cooling plate 3 located within the spraying range of the explosion-proof valve 113, so that the cooling medium released by the first liquid cooling plate 3 can be sprayed toward the explosion-proof valve 113 and the surrounding area, and the cooling medium that enters the runaway battery cell 11 through the explosion-proof valve 113 cools the inside of the runaway battery cell 11; in the embodiment of the present invention, the first liquid cooling plate 3 is arranged on the pole 111 of the battery cell 11, and ... The projections of the first liquid cooling plate 3 and the explosion-proof valve 113 of the battery cell 11 on the same end face do not overlap, that is, they are completely offset from each other, so as to make full use of the space in the height direction of the battery cell 11, and reasonably plan the relative positions of the first liquid cooling plate 3 and the explosion-proof valve 113 of the battery cell 11, so as to avoid interference with the opening of the explosion-proof valve 113 and the ejection of high-temperature substances, so that the cooling medium released by the first liquid cooling plate 3 can flow into the inside of the out-of-control battery cell 11 more easily, and the cooling effect on the out-of-control battery cell 11 is better, thereby suppressing heat spread.

[0081] The battery module assembly of the embodiment of the present invention can directly dissipate the heat generated on the pole through the first liquid cooling plate connected to the pole in a timely and rapid manner, thereby improving the overall cooling capacity of the battery module assembly, preventing heat from accumulating near the pole and causing the risk of thermal runaway of the battery cell due to local excessive temperature. It is suitable for fast-charging batteries, which is beneficial to improving the fast-charging capability and safety of use of the battery module.

[0082] The cooling device in the related art cannot be directly used as the first liquid cooling plate in the embodiment of the present invention for the following reasons:

[0083] 1. The cooling device on the surface of the battery cell pole and its bar is made of metal material (such as aluminum alloy, etc.). When the battery cell is thermally runaway, it is difficult to be melted through, so that the cooling medium cannot be sprayed toward the explosion-proof valve, and the process of heat spread cannot be effectively suppressed.

[0084] 2. The cooling device on the surface of the battery cell pole and its tab is made of non-metallic material (such as nylon, etc.). When the position relationship between the cooling device and the explosion-proof valve is not set reasonably (for example, there is a long distance between the projection of the cooling device and the explosion-proof valve in the height direction of the battery cell), or the material model is not set reasonably (such as the melting point is too high or thermosetting material is used), the function of cooling the battery cell by leakage of the cooling medium cannot be achieved.

[0085] Based on this, in the embodiment of the present invention, a weak area is set for the first liquid cooling plate 3 which is difficult to be melted through, or the material of the first liquid cooling plate 3 is changed to solve the above defects and problems.

[0086] In some embodiments, the first liquid cooling plate 3 has a weak area, and the weak area is located within the spraying range of the explosion-proof valve 113 .

[0087] It should be understood that when the battery cell 11 thermally runs away, the explosion-proof valve 113 will spray out high-temperature substances, and the weak area is located within the spraying range of the explosion-proof valve 113, thereby ensuring that the weak area is melted through, and the cooling medium in the first liquid cooling plate 3 is sprayed toward the explosion-proof valve 113, so that the cooling medium can enter the battery cell through the explosion-proof valve 113.

[0088] Specifically, the weak area of ​​the first liquid cooling plate 3 is determined according to the relative positions of the first liquid cooling plate 3 and the explosion-proof valve 113 to ensure that the weak area is within the high-temperature material spraying range of the explosion-proof valve 113 when the battery cell 11 is thermally runaway. At the same time, in order to enable the weak area to melt through in time and spray the cooling medium toward the explosion-proof valve 113, the structure and wall thickness of the weak area can be designed, and the parameters such as the wall thickness and material of the first liquid cooling plate 3 as a whole can also be designed. The spatial position relationship between the first liquid cooling plate 3 and the explosion-proof valve 113 can also be further constrained.

[0089] When the first liquid cooling plate 3 is made of metal, since the first liquid cooling plate 3 has a certain thickness, if a weak zone is not set, the high-temperature substance sprayed by the explosion-proof valve 113 is not easy to quickly melt through the first liquid cooling plate 3 made of metal. By setting the portion of the first liquid cooling plate 3 within the spraying range as a weak zone, the shell thickness of the weak zone of the first liquid cooling plate 3 is less than the shell thickness of other areas of the first liquid cooling plate 3, which can ensure that the portion of the first liquid cooling plate 3 within the spraying range is melted through in time, and the out-of-control battery cell 11 is cooled.

[0090] Alternatively, if Figure 1The A parts within the dotted line range shown in the figure are all weak areas. The weak areas and the explosion-proof valve are arranged opposite to each other in the length direction of the battery core. The wall thickness of the weak areas is smaller than the wall thickness of the shell of other areas of the first liquid cooling plate 3.

[0091] Optionally, Figure 1 The first liquid cooling plate 3 shown in the figure extends along the width direction of the battery cell, and the entire length of the first liquid cooling plate 3 on one side close to the explosion-proof valve in the length direction of the battery cell is set as a weak area, and the wall thickness of the weak area is thinner than that of other parts.

[0092] Optionally, the weak zone is provided at Figure 1 The wall thickness of the multiple weak points in the A part within the dotted line range shown in FIG. 1 is smaller than the wall thickness of the shell of other areas of the first liquid cooling plate 3. For example, Figure 1 Two, three or five countersunk holes are arranged in the A region within the dotted line range shown in the figure. The countersunk holes do not penetrate the shell of the first liquid cooling plate 3, but the wall thickness at the bottom of the countersunk holes is thinner than the shell wall thickness at other positions and is more easily melted through.

[0093] For example, the material of the first liquid cooling plate 3 is aluminum alloy, and the wall thickness of the first liquid cooling plate 3 within the spraying range is 0.1mm to 2mm. Specifically, the wall thickness of the weak area of ​​the first liquid cooling plate 3 can be 0.1mm, 0.25mm, 0.45mm or 2mm, and the wall thickness of the shell of other areas of the first liquid cooling plate 3 is greater than 2mm. Specifically, the wall thickness of the shell of other areas of the first liquid cooling plate 3 can be 2.5mm, 3mm, 3.5mm, etc., which can not only ensure the overall structural strength of the first liquid cooling plate 3 and prevent the first liquid cooling plate 3 from being deformed or broken after a collision, but also ensure that the weak area can be melted through in time when thermal runaway occurs in the battery cell 11, and the cooling medium can be released.

[0094] In some embodiments, the material of the first liquid cooling plate 3 is a composite material. Specifically, a thermoplastic composite material can be used. For example, the material of the first liquid cooling plate 3 is a composite material including PPA (polyphthalamide) or a composite material including PPO (polystyrene). When the battery cell 11 thermally runs away, the first liquid cooling plate 3 can be melted through in time and a cooling medium can be sprayed toward the runaway battery cell 11.

[0095] In addition, the first liquid cooling plate 3 is made of a composite material as a whole, which has a stable melting point and a relatively low melting point. When the melting point is less than or equal to 400°C, when the battery cell thermally runs away, the portion of the first liquid cooling plate 3 within the injection range can be melted through in time. Therefore, a weak area does not need to be set, that is, at this time, there is no need to reduce the wall thickness of the portion of the first liquid cooling plate 3 within the injection range.

[0096] For example, the material of the first liquid cooling plate 3 is a composite material including PPA, and the shell thickness of the first liquid cooling plate 3 can be 1mm, 1.3mm, 1.6mm or 2mm. No weak area is set on the first liquid cooling plate 3, that is, the wall thickness of the first liquid cooling plate is the same. When thermal runaway occurs in the battery cell, the high-temperature material sprayed from the explosion-proof valve can directly melt through the part within the spraying range, meeting the performance requirements. At this time, not setting a weak area can reduce the difficulty and cost of the manufacturing process.

[0097] For another example, relative to the previous example, when the melting point of the composite material used to make the first liquid cooling plate 3 becomes higher, or when the wall thickness of the first liquid cooling plate 3 made of the composite material is greater than 2 mm, in order to prevent the high-temperature material sprayed from the explosion-proof valve from failing to melt through the part of the first liquid cooling plate 3 within the spraying range in time when thermal runaway occurs in the battery cell, it is necessary to set a weak area within the spraying range of the first liquid cooling plate 3.

[0098] In the solution of the spray device facing the explosion-proof valve in the related art, when the distance between the spray device and the explosion-proof valve in the height direction of the battery cell is ≤8mm, it will affect the exhaust space of the explosion-proof valve. When the distance between the spray device and the explosion-proof valve in the height direction of the battery cell is ≤5mm, the spray device will further hinder the opening of the explosion-proof valve. Although this defect in the related art can be avoided by reasonably designing the distance between the spray device and the explosion-proof valve, the distance between the spray device and the explosion-proof valve in the height direction of the battery cell is too large (greater than 8mm), which will greatly reduce the space integration efficiency of the battery pack.

[0099] In the scheme of the first liquid cooling plate and the explosion-proof valve being completely offset in the embodiment of the present invention, in order to avoid the unreasonable design of the spatial position relationship between the first liquid cooling plate and the explosion-proof valve, which is specifically reflected in the distance D between the projections of the first liquid cooling plate and the explosion-proof valve along the height direction of the battery cell (i.e., the first offset distance) and the distance H between the first liquid cooling plate and the explosion-proof valve in the height direction of the battery cell, when the distance D and the distance H are too large, it is easy to cause the high-temperature material ejected by the explosion-proof valve to fail to melt through the first liquid cooling plate, or it takes a long time to melt through the first liquid cooling plate, thereby resulting in poor suppression effect of heat spread and unfavorable cooling of the out-of-control battery cell. Too large a distance H will also lead to low space utilization in the height direction of the battery cell (wasted on the gap between the first liquid cooling plate and the battery cell), and it is impossible to use more space to increase the battery power.

[0100] Therefore, the embodiment of the present invention conducts a simulation test on the distance between the first liquid cooling plate and the explosion-proof valve in the height direction of the battery cell, optimizes the distance between the projections of the first liquid cooling plate and the explosion-proof valve along the height direction of the battery cell (i.e., the first offset distance) D, and the distance between the first liquid cooling plate and the explosion-proof valve in the height direction of the battery cell (the second offset distance) H, and reasonably determines them as follows: the first offset distance D is 0 to 30 mm, and the second offset distance H is 0 to 20 mm.

[0101] For the second offset distance H, when the value of the second offset distance H is any value in the range of 0 to 20 mm, the first liquid cooling plate 3 can have both the advantages of spraying cooling medium to suppress heat spread when the battery cell is under thermal runaway and the advantages of improving the thermal management performance of the battery cell under normal working conditions, without affecting the advantages of suppressing heat spread and improving the thermal management performance of the battery cell. Further, when the installation space for arranging the battery cell is not limited, the battery power meets the demand and there is no need to deliberately compress the space to increase the power, the second offset distance H is any value between 0 and 20 mm; when the installation space of the battery cell of some vehicle models is limited, and it is necessary to increase the battery power through more reasonable planning of the vehicle space, or to reserve space for the arrangement of other components, the size of the second offset distance H can be reduced, for example, the second offset distance H is selected as any value between 0 and 10 mm. At this time, more space can be saved for increasing the battery power or for arranging other components, which is more practical in actual applications.

[0102] like Figure 3 As shown, in some embodiments, there is a first offset distance between the projections of the first liquid cooling plate 3 and the explosion-proof valve 113 in the height direction of the battery cell 11, and the first offset distance is 0 to 30 mm.

[0103] It should be noted that the projections of the first liquid cooling plate 3 and the explosion-proof valve 113 in the height direction of the battery cell 11 are completely offset from each other, and the first offset distance is Figure 3 The distance D shown in .

[0104] The offset distance between the projection of the first liquid cooling plate 3 on the first end surface and the projection of the explosion-proof valve 113 in the height direction of the battery cell 11 can be determined according to the spray angle range of the high-temperature substance and the temperature radiation range of the high-temperature substance when the battery cell 11 thermally runs away.

[0105] Since the high-temperature material sprayed out by the explosion-proof valve 113 of the battery cell 11 is roughly sprayed out along the height direction of the battery cell 11 and is approximately inverted cone-shaped. Therefore, when the projections of the first liquid cooling plate 3 and the explosion-proof valve 113 of the battery cell 11 in the height direction of the battery cell 11 are completely staggered and the staggered distance is too large, the first liquid cooling plate 3 cannot be directly touched by the high-temperature material, and then the weak area cannot be melted through. In response to this potential problem, by studying the positional relationship between the explosion-proof valve of the battery cell 11 and the first liquid cooling plate 3, the size range of the first offset distance D is confirmed, so that the high-temperature material sprayed out of the out-of-control battery cell 11 can melt through the first liquid cooling plate 3 by means of thermal radiation, heat conduction, thermal convection, etc. The test results show that the first offset distance between the first liquid cooling plate 3 and the explosion-proof valve 113 of the battery cell 11 can meet the requirements within 0 to 30 mm.

[0106] In addition, when the projections of the first liquid cooling plate 3 and the explosion-proof valve 113 in the height direction of the battery cell 11 partially overlap, it is easy to cause the melt-through gap on the first liquid cooling plate 3 to be too large, resulting in the spraying area being not concentrated, the spraying liquid losing too quickly, and even causing the first liquid cooling plate 3 to be disconnected as a whole, which will also interfere with the high-temperature substance, affecting the spraying of the cooling medium in the first liquid cooling plate 3, and the high-temperature substance in the battery cell 11 will accumulate between the first liquid cooling plate 3 and the battery cell 11.

[0107] When the first offset distance is too large, for example, the first offset distance is 40 mm, 50 mm or 63 mm, the melt-through gap on the first liquid cooling plate 3 will be smaller or cannot be melted through, which may easily lead to the first liquid cooling plate 3 not being melted through in a timely and effective manner, or the melting speed of the first liquid cooling plate 3 will be relatively slow, and spraying cannot be performed in time, and heat spread cannot be effectively suppressed.

[0108] Specifically, the first offset distance D can be 0, 8mm, 20mm or 30mm. When the first offset distance D gradually increases from 0 to 30mm, when the spray range of the explosion-proof valve 113 is constant, the portion of the first liquid cooling plate 3 within the spray range of the explosion-proof valve 113 gradually decreases. When D is 0mm, it can be ensured that there is a relatively large melting area on the first liquid cooling plate 3, and the spray flow rate is relatively larger. At this time, the portion of the first liquid cooling plate 3 within the spray range of the explosion-proof valve 113 is more likely to be melted after direct contact with the high-temperature substance; when D is 30mm, the portion of the first liquid cooling plate 3 within the spray range of the explosion-proof valve 113 is more likely to be melted by the heat radiation, heat conduction, heat convection and other means of the high-temperature substance. There is a larger space between the first liquid cooling plate 3 and the explosion-proof valve 113, which is convenient for the release of the high-temperature substance inside the battery cell and reduces the internal pressure of the battery cell. When D is 20 mm, after the portion of the first liquid cooling plate 3 within the spraying range of the explosion-proof valve 113 is melted through, it has a better spray angle, so that the cooling medium can spray the explosion-proof valve 113 in an approximately fan-shaped manner, and at the same time, there can be sufficient release space between the first liquid cooling plate 3 and the explosion-proof valve 113; when D is 8 mm, the cooling medium sprayed after the first liquid cooling plate 3 is melted through has a better spray flow and spray angle, and the spray effect is better.

[0109] Furthermore, if Figure 3 As shown, the value of the first offset distance D is 8 mm. While ensuring that the first liquid cooling plate 3 and the explosion-proof valve 113 are completely offset in the height direction of the battery cell and do not affect the opening of the explosion-proof valve 113 and the injection of high-temperature substances, the first liquid cooling plate 3 completely covers the pole 111 in the height direction of the battery cell 11, and can be better attached to the pole, effectively cool the pole, and meet the requirements of the thermal management performance of the battery under the battery fast charging condition.

[0110] like Figure 3 As shown, in some embodiments, the first liquid cooling plate 3 and the explosion-proof valve 113 have a second offset distance in the height direction of the battery core 11, and the second offset distance is 0 to 20 mm.

[0111] It should be understood that the first liquid cooling plate 3 and the explosion-proof valve 113 are spaced apart from each other in the height direction of the battery cell 11 (ie, a second offset distance), and the second offset distance is Figure 3 The distance H shown in .

[0112] When the spacing distance between the first liquid cooling plate 3 and the explosion-proof valve 113 in the height direction of the battery cell 11 is too large, for example, the second offset distance is 25 mm, 36.5 mm or 40 mm, the battery module assembly 100 will be too large in the height direction of the battery cell 11, and the occupied space will increase, the space of the entire vehicle will not be utilized, and the battery charge capacity will be affected.

[0113] The second offset distance H can be 0, 6.7mm, 13mm or 20mm. Under the premise that the structural size of the battery cell itself remains unchanged, when the second offset distance H is 0mm, the cooling medium sprayed after the first liquid cooling plate 3 is melted through is more likely to flow toward the explosion-proof valve along the end face of the battery cell 11, thereby more easily entering the interior of the battery cell. When the second offset distance H is 20mm, there is sufficient space for releasing high-temperature substances above the explosion-proof valve 113, which is more helpful to reduce the pressure inside the battery cell. When the second offset distance H is 13mm, while ensuring that there is a more reasonable space for releasing high-temperature substances above the explosion-proof valve 113, the size of the battery module assembly in the height direction of the battery cell can be reduced. Under the premise of sufficient installation space, more space can be used to increase the power of the battery cell 11. When the second offset distance H is 6.7mm, the size of the battery module assembly in the height direction of the battery cell can be further reduced, the power density of the battery can be improved, the integration of the battery module assembly can be higher, and the spraying effect of the cooling medium can also be better.

[0114] Furthermore, the distance between the first liquid cooling plate and the explosion-proof valve in the height direction of the battery cell (the second offset distance) depends on the pole height + the thickness of the electrical connection bar + the thickness of the thermal conductive adhesive. For example, the pole height is generally 3.2 mm (square shell battery cell), the thickness of the electrical connection bar is generally (1.5 to 2 mm), and the thickness of the thermal conductive adhesive is (0.5 to 1.5 mm). Therefore, the distance between the first liquid cooling plate and the explosion-proof valve in the height direction of the battery cell is 5.2 mm to 6.7 mm. When the bar and / or thermal conductive adhesive are not provided, the distance between the first liquid cooling plate and the explosion-proof valve in the height direction of the battery cell can be further reduced. Compared with the related art in which the spray device is directly opposite to the explosion-proof valve, the spacing between the spray device and the explosion-proof valve in the height direction of the battery cell is ≥8 mm, which can save more than 1.3 mm of space and can use more space to improve the power density of the battery.

[0115] In the structure of the above embodiment, not only the installation position of the first liquid cooling plate 3 and the relative position of the first liquid cooling plate 3 and the explosion-proof valve 113 are defined, ensuring that the space occupied by the battery module assembly 100 can meet the requirements of the installation position and optimize the overall space layout, but also the first liquid cooling plate 3 can more accurately spray the high-temperature material injection area and the surrounding area when melting through, thereby improving the cooling effect and effectively preventing heat spread.

[0116] In the related art, when the spray device is facing the explosion-proof valve of the out-of-control battery cell 11, when the distance between the spray device and the explosion-proof valve of the battery cell 11 in the height direction of the battery cell 11 is close, not only will the spray device hinder the opening of the explosion-proof valve of the battery cell 11, but also the spray device will affect the exhaust space of the explosion-proof valve of the battery cell 11, thereby causing high-temperature substances to accumulate between the spray device and the battery cell 11, the pressure inside the battery cell 11 package increases, and there is a risk of failure of the battery cell 11 structure.

[0117] Although the above problem can be avoided to a certain extent by increasing the distance between the spray device and the explosion-proof valve in the height direction of the battery cell 11, it will cause the spray device to be at a greater distance from the explosion-proof valve of the battery cell 11, greatly reducing the spatial integration efficiency of the battery pack 1000.

[0118] On the contrary, in the embodiment of the present invention, by designing the spatial position between the first liquid cooling plate 3 and the explosion-proof valve 113, the size limitation of the first liquid cooling plate 3 in the height direction of the battery cell 11 is greatly reduced, and the spatial position between the first liquid cooling plate 3 and the explosion-proof valve 113 can be more flexibly adjusted according to the spatial layout of the entire vehicle.

[0119] In order to further improve the performance of the first liquid cooling plate during thermal runaway of the battery cell and under normal operating conditions, the present invention further designs and constrains the material, melting point, wall thickness, etc. of the first liquid cooling plate, thereby ensuring that the first liquid cooling plate in the present invention has the advantage of spraying cooling medium to suppress the heat spread of the runaway battery cell, and also has the advantage of cooling the battery cell poles to improve the thermal management performance of the battery.

[0120] Specifically, the present invention determines the following features of the first liquid cooling plate: a. using thermoplastic material (PPA, PPO, etc.); b. melting point ≤ 400°C; c. wall thickness ≤ 2mm; d. thermal conductivity ≥ 0.5W / m·K. The following is a further detailed description of the various features of the first liquid cooling plate 3 in conjunction with specific embodiments.

[0121] In some embodiments, the melting point of the meltable portion of the first liquid cooling plate 3 is less than or equal to 400°C.

[0122] Specifically, the melting point of the fusible portion of the first liquid cold plate 3 of the embodiment of the present invention is less than or equal to 400°C. The melting point of the fusible portion of the first liquid cold plate 3 of the embodiment of the present invention may be 400°C, 310°C or 220°C, and at the same time, the melting point of the first liquid cold plate 3 must be greater than the operating temperature of the battery under normal operation. When the melting point of the first liquid cold plate 3 is 220°C, when the battery cell 11 has thermal runaway, it can be melted through faster, and the melting speed is fast, and the heat spread of the battery cell can be suppressed earlier by spraying cooling medium. When the melting point of the first liquid cold plate 3 is 400°C, the deformation of the first liquid cold plate 3 can be reduced, and the first liquid cold plate 3 can be prevented from further deformation due to heat radiation, heat conduction, heat convection, etc. after melting through, which affects the structural stability of the first liquid cold plate 3. When the melting point of the first liquid cold plate 3 is 210°C, on the premise of ensuring that the first liquid cold plate 3 is melted through in time, the stability of the first liquid cold plate 3 in a high temperature environment can also be improved.

[0123] In the embodiment of the present invention, the meltable portion of the first liquid cooling plate 3 may be only the portion within the spraying range, or the entire first liquid cooling plate 3 may be melted through. In this case, the melting point of the entire first liquid cooling plate 3 is less than or equal to 400°C.

[0124] When the battery cell 11 experiences thermal runaway, the ejected high-temperature material can melt through the first liquid cooling plate 3 in a very short time, so that the cooling medium flows out from the melt-through position and sprays and cools the runaway battery cell 11. During the cooling process, the cooling medium will be directly sprayed onto the surface of the battery cell 11 or inside the battery cell 11, and the cooling medium absorbs heat and evaporates, thereby reducing the temperature of the battery cell 11 and the surrounding environment.

[0125] For example, the melting point of the part of the first liquid cooling plate 3 within the spraying range is 220°C. When the battery cell 11 is thermally runaway, the temperature of the high-temperature substance sprayed out by the explosion-proof valve 113 can reach about 500°C. The part of the first liquid cooling plate 3 within the spraying range will not only be melted through when in contact with the high-temperature substance, but also be able to melt through the first liquid cooling plate 3 by means of thermal radiation of the high-temperature substance before the high-temperature substance contacts the first liquid cooling plate 3, and the first liquid cooling plate 3 releases the cooling medium in advance, so that the cooling medium can enter the battery cell 11 earlier, reduce the temperature inside the battery cell 11, and inhibit heat spread.

[0126] In some embodiments, the wall thickness of the meltable portion of the first liquid cooling plate 3 is 0.1 mm to 2 mm.

[0127] That is to say, the wall thickness of the fusible part of the first liquid cooling plate 3 can be 0.1mm, 0.8mm or 2mm, and the fusible part refers to the part located within the injection range. For example, when the first liquid cooling plate 3 is provided with a weak area, the fusible part is the weak area located within the injection range. For example, when the weak area is not provided, the fusible part is the part on the first liquid cooling plate 3 covered by the injection range. Of course, the wall thickness of the first liquid cooling plate 3 can be consistent and both 0.1mm to 2mm. At this time, it is not necessary to reduce the wall thickness or set a weak area for the layout position, thereby reducing the manufacturing cost and the difficulty of processing. When the battery cell 11 has thermal runaway, it can ensure that the high-temperature material sprayed by the explosion-proof valve 113 melts through the part of the first liquid cooling plate 3 located within the injection range in time. When the wall thickness of the fusible part of the first liquid cooling plate 3 located within the injection range is 0.1mm, due to the thin wall thickness, it can be melted through in time, and the melting speed is fast. The cooling medium can be sprayed out in time at the early stage of thermal runaway of the battery cell, thereby improving the suppression effect of heat spread. When the wall thickness of the meltable portion of the first liquid cooling plate 3 within the spraying range is 2 mm, the structural strength of the region can be improved to prevent the corresponding region from being broken due to stress concentration caused by vibration or impact during use. When the wall thickness of the meltable portion of the first liquid cooling plate 3 within the spraying range is 0.8 mm, while ensuring the structural strength of the portion of the first liquid cooling plate 3 within the spraying range, the melting speed of the corresponding portion can also be improved.

[0128] For example, when the main body of the first liquid cooling plate 3 is made of metal, the shell wall thickness of the first liquid cooling plate 3 is 2.5 mm, and the wall thickness of the first liquid cooling plate 3 within the spraying range is set to 0.2 mm, thereby forming a weak area to ensure that the weak area can be melted through in time.

[0129] For another example, when the entire first liquid cooling plate is made of composite material, even if the wall thickness of the first liquid cooling plate 3 within the spraying range is not reduced, it can be melted through in time, so no weak area is required, and the wall thickness of the entire first liquid cooling plate is 2 mm.

[0130] When the wall thickness of the first liquid cooling plate 3 within the spraying range is too thin and is less than 0.1 mm, for example, when the wall thickness of the first liquid cooling plate 3 is 0.086 mm, 0.07 mm or 0.06 mm, the structural stability of the first liquid cooling plate 3 is poor, and it is easy to be damaged due to its own structural stability, resulting in leakage of the cooling medium without losing control of the battery cell 11.

[0131] When the wall thickness of the first liquid cooling plate 3 within the spraying range is too thick and greater than 2 mm, for example, when the wall thickness of the first liquid cooling plate 3 is 2.5 mm, 3 mm, or 3.7 mm, the melting time of the first liquid cooling plate 3 within the spraying range will be long, and the size of the melting notch of the first liquid cooling plate 3 will become smaller, so that the cooling medium cannot be sprayed in time, and the runaway battery cell 11 cannot be effectively covered, which affects the control effect of heat spread after thermal runaway and increases uncontrollable factors.

[0132] Furthermore, the cooling medium in the first liquid cooling plate 3 of the embodiment of the present invention can be connected to the liquid cooling circuit of the battery thermal management system, so as to perform thermal management on the pole 111 of the battery cell 11 and improve the battery charging and discharging performance and cycle life.

[0133] However, when the cooling device in the related art uses non-metallic materials, ordinary non-metallic materials have low thermal conductivity (≤0.4W / m·K), and the thermal management effect of non-metallic materials on the battery cell 11 and its electrical connection bar 2 is poorer than that of the first liquid cooling plate 3 made of metal materials. Therefore, the thermal conductivity of the first liquid cooling plate 3 of the embodiment of the present invention is greater than or equal to 0.5W / m·K, and can be specifically 0.5W / m·K, 0.8, 1.1W / m·K, 2W / m·K or a higher thermal conductivity. For example, the material of the first liquid cooling plate 3 is a composite material including PPA (polyphthalamide) with a thermal conductivity of 0.75W / m·K, or the material of the first liquid cooling plate 3 is a composite material including PPO (polystyrene) with a thermal conductivity of 1W / m·K. At this time, the thermal management effect of the first liquid cooling plate 3 using the composite material on the battery cell 11 in the embodiment of the present invention can be basically the same as the effect obtained by the metal first liquid cooling plate 3 in the related art, and can transfer the heat on the pole 111 to the cooling medium in the first liquid cooling plate 3 and quickly diffuse it out, thereby meeting the thermal management requirements of the battery under normal fast charging conditions.

[0134] Therefore, the first liquid cooling plate 3 of the embodiment of the present invention can spray cooling medium under the condition of thermal runaway of the battery cell, thereby suppressing the spread of heat, and can also cool the pole to improve the thermal management performance of the battery cell.

[0135] When the first liquid cooling plate 3 of the embodiment of the present invention is made of composite material, the overall material and properties tend to be consistent. Therefore, the first liquid cooling plate 3 does not need to be provided with a weak area, and the high-temperature material sprayed from the battery cell 11 can more accurately and timely melt through the portion of the first liquid cooling plate 3 within the spraying range.

[0136] The cooling medium in the first liquid cooling plate 3 can be water, 50% ethylene glycol coolant, fluorinated liquid, refrigerant (R134a, etc.) and other cooling materials.

[0137] In the embodiment of the present invention, the first liquid cooling plate 3 can not only spray cooling medium on the runaway battery cell 11 by locally melting through when the battery cell 11 is in thermal runaway, thereby achieving a cooling effect, but can also cool the pole 111 when the battery cell 11 is working normally, thereby improving the thermal management performance of the battery, reducing the temperature of the battery during normal operation, and avoiding thermal runaway of the battery.

[0138] Therefore, the first liquid cooling plate 3 is connected to the pole 111 through the heat conducting layer, which improves the heat transfer performance between the first liquid cooling plate 3 and the pole 111. The heat conducting layer can be a heat conducting adhesive, a heat conducting pad, a double-sided adhesive or a structural adhesive.

[0139] Alternatively, the first liquid cooling plate 3 is directly connected to the pole 111 without any contact, and the first liquid cooling plate 3 and the pole 111 are directly in contact with each other to achieve heat transfer.

[0140] Table 1 Performance parameter comparison of aluminum alloy liquid cooling device and non-metal first liquid cooling plate under thermal runaway condition

[0141]

[0142] It can be seen from the test data in Table 1 that when the first offset distance between the first liquid cooling plate and the battery cell explosion-proof valve in the embodiment of the present invention is 10 mm, 1 mm and 8 mm, the maximum temperature of the battery cell adjacent to the out-of-control battery cell can be effectively reduced (reduced by 58.3°C, 60.7°C and 68.8°C respectively) compared with the aluminum alloy liquid cooling device in the related art, thereby suppressing the heat spread from the out-of-control battery cell to the adjacent battery cell, thereby ensuring the safety of the battery system and avoiding the consequences of cascading thermal runaway.

[0143] Furthermore, from the test results of the first liquid cooling plate and the explosion-proof valve with the first offset distance D being 1 mm, 8 mm and 10 mm in Table 1, it can be seen that even if the staggered first offset distances are different, the difference in the cooling effect is small, and the requirement of suppressing the spread of thermal runaway of the battery cell can be met.

[0144] From the test results of the first offset distance D of the first liquid cooling plate and the explosion-proof valve being 1 mm, 8 mm and 10 mm in Table 1, it can be seen that the first offset distance D of the first liquid cooling plate and the explosion-proof valve is not as small as possible, nor is it as large as possible. Therefore, the embodiment of the present invention optimizes the design of the first offset distance D and the second offset distance H so that it can meet the requirement of preventing heat spread when the battery cell is in thermal runaway.

[0145] Table 2 Performance parameter comparison of aluminum alloy liquid cooling device and non-metal first liquid cooling plate under fast charging condition

[0146]

[0147] From the data in Table 2, it can be seen that the present invention uses the solution provided by the embodiment of the present invention through simulation calculation, and the thermal conductivity of the first liquid cooling plate is 0.7W / m·K, which can achieve the ability of fast charging in 628s to reach a range of 500km. Even compared with the traditional aluminum alloy liquid cooling device, the fast charging time is only extended by 12s, which is a small difference and can meet the thermal management requirements under fast charging conditions.

[0148] In some embodiments, there are multiple battery cells 11, and the multiple battery cells 11 are arranged in an array to form a battery module 1. The battery module 1 includes at least one battery group arranged along a first direction, and the first liquid cooling plate 3 extends along the first direction; wherein the first direction is perpendicular to the height direction of the battery cell 11.

[0149] It should be understood that Figure 4 The front-to-back direction shown in is the length direction of the battery cell 11. Figure 4 The left-right direction shown in is the width direction of the battery cell 11. Figure 4 The up-down direction shown in is the height direction of the battery cell 11. The first direction may be the length direction of the battery cell 11 or the width direction of the battery cell 11, and the extension direction of the first liquid cooling plate 3 is determined thereby, while ensuring the relative position relationship between the first liquid cooling plate 3 and the explosion-proof valve 113, and ensuring that when any of the multiple battery cells 11 has thermal runaway, the first liquid cooling plate 3 can melt through in time and spray cooling medium to the runaway battery cell 11.

[0150] Furthermore, the length of the first liquid cooling plate 3 in the first direction is greater than or equal to the length of the battery pack in the first direction.

[0151] It should be noted that the first direction can be the length direction or the width direction of the battery cell 11. Each battery pack in the battery module includes multiple battery cells 11. The multiple battery cells 11 in the same battery pack are arranged side by side along the length direction of the battery cell 11 or the width direction of the battery cell 11. By limiting the length of the first liquid cooling plate 3, the first liquid cooling plate 3 can cover all the battery cells 11 along the battery pack. At this time, if any battery cell 11 has thermal runaway, the sprayed cooling medium can be accurately sprayed onto the thermal runaway battery cell 11 by melting through the part of the first liquid cooling plate 3 within the spraying range.

[0152] In some embodiments, the first direction is the length direction of the battery cell 11 , two first liquid cooling plates 3 are attached above a pole 111 , the two first liquid cooling plates 3 are arranged at intervals along the width direction of the battery cell 11 , and the explosion-proof valve 113 is located between the two first liquid cooling plates 3 .

[0153] It should be understood that the pole 111 in the battery cell 11 includes a positive pole and a negative pole, and the positive pole, the explosion-proof valve 113 and the negative pole are arranged at intervals along the length direction of the battery cell 11. When the cross-sectional size of the pole 111 is large and the cross-sectional size of the explosion-proof valve 113 (i.e., the explosion-proof valve of the battery cell 11) is smaller than that of the pole 111, two first liquid cooling plates 3 can be arranged on one pole 111, and the first liquid cooling plates 3 extend along the length direction of the battery cell 11. The two first liquid cooling plates 3 are respectively arranged on both sides of the explosion-proof valve of the battery cell 11, and the projections of the two first liquid cooling plates 3 and the explosion-proof valve of the battery cell 11 in the height direction of the battery cell 11 are completely deviated from the arrangement. When the battery cell 11 thermally runs away, the high-temperature material sprayed from the explosion-proof valve of the battery cell 11 can melt through the weak areas on the two first liquid cooling plates 3 at the same time, thereby having a better cooling effect on the battery cell 11.

[0154] In some embodiments, the first direction is the width direction of the battery cell 11 , and a first liquid cooling plate 3 is attached above a pole 111 .

[0155] At this time, if Figure 1 As shown, the first liquid flow plate extends along the width direction of the battery cell 11, and a first liquid flow plate is provided on the positive electrode column and the negative electrode column of the battery cell 11, and the two first liquid flow plates respectively located on the positive electrode column and the negative electrode column are arranged on both sides of the explosion-proof valve 113. When the explosion-proof valve 113 sprays out high-temperature substances, the high-temperature substances can also melt through the first liquid cooling plates 3 on both sides within the spraying range at the same time, so that the first liquid cooling plates 3 on both sides spray out cooling medium at the same time, so that the sprayed cooling medium can completely cover the explosion-proof valve 113, thereby improving the cooling effect.

[0156] Optionally, a heat conductive layer is provided between the first liquid cooling plate 3 and the pole 111 , and the heat conductive layer may be a heat conductive structural adhesive, a heat conductive pad, a heat conductive gel, a heat conductive silicone grease, a structural adhesive, etc., to improve the heat transfer efficiency between the first liquid cooling plate 3 and the pole 111 .

[0157] like Figure 5-Figure 7 As shown, the battery module assembly 100 of the embodiment of the present invention further includes a bar plate 2 , the bar plate 2 is connected to the pole 111 , and the first liquid cooling plate 3 is attached to the bar plate 2 .

[0158] At this time, the heat-conducting layer is arranged between the first liquid cooling plate 3 and the bar plate 2 , thereby improving the heat transfer efficiency between the bar plate 2 and the first liquid cooling plate 3 .

[0159] The battery module assembly 100 of the embodiment of the present invention, by providing a first liquid cooling plate 3 on the bar piece 2 connected to the pole 111, can directly dissipate the heat generated on the pole 111 through the first liquid cooling plate 3 in a timely and rapid manner, thereby improving the overall cooling capacity of the battery module 1 by the first liquid cooling plate 3, preventing heat from accumulating at the pole 111 and causing the temperature of the battery cell 11 to be too high, limiting the charging current, being suitable for fast-charging batteries, and further facilitating improving the fast-charging capability and safety of use of the battery module 1.

[0160] Therefore, the battery module assembly 100 of the embodiment of the present invention has the advantage of suppressing heat spread when the battery cell has thermal runaway, and at the same time has the advantage of improving the heat dissipation capacity and fast charging capacity at the pole 111 under normal operating conditions.

[0161] Further, there are multiple bar sheets 2, each bar sheet 2 is connected to the poles 111 of two adjacent battery cells 11 to form a bar sheet row, and the first liquid cooling plate 3 is attached to the bar sheet row. The bar sheet 2 can connect two adjacent battery cells 11 in the battery module 1 in series and / or in parallel. The pole 111 is arranged on the top of the battery cell 11, the bar sheet 2 is connected to the pole 111, and the first liquid cooling plate 3 is arranged on the upper surface of the bar sheet 2.

[0162] In some embodiments, Figure 6 and Figure 7 As shown, the first liquid cooling plate 3 includes a connected liquid cooling portion 31 and an overlapping edge 32 , the liquid cooling portion 31 is attached to the bar sheet row, and the overlapping edge 32 is attached to the shoulder 112 of the battery cell 11 .

[0163] The battery module assembly 100 of the embodiment of the present invention divides the first liquid cooling plate 3 into a connected liquid cooling portion 31 and an overlapped edge 32, wherein the liquid cooling portion 31 is attached to the bar sheet row, and the overlapped edge 32 is attached to the shoulder 112 of the battery cell 11, and the overlapped edge 32 can not only dissipate heat from the shoulder 112 of the battery cell 11, but also dissipate heat from the shoulder 112 of the battery cell 11 through the liquid cooling portion 31, which not only helps to reduce or even eliminate the temperature difference between the shoulder 112 of the battery cell 11 and the pole 111 (the overlapped edge 32 has the function of evenly dissipating heat), but also reduces the overall cooling capacity of the battery module 1. As a result, the battery module assembly 100 further improves the heat dissipation capacity of the battery module 1.

[0164] For example, the battery pack in the battery module 1 includes a plurality of battery cells 11 arranged along the width direction of the battery cells 11, and each battery cell 11 has a shoulder 112. The positive electrode column and the negative electrode column of the battery cell 11 are both arranged on the top surface of the battery cell 11. When the positive electrode column and the negative electrode column are arranged near the middle of the battery cell 11, the shoulder 112 can be formed on both sides of the length direction of the battery cell 11. When the positive electrode column and the negative electrode column are arranged near the two edges of the length direction of the battery cell 11, the shoulder 112 is formed between the explosion-proof valve 113 and the positive electrode column, and between the explosion-proof valve 113 and the negative electrode column.

[0165] For another example, the battery pack in the battery module 1 includes a plurality of battery cells 11 arranged along the length direction of the battery cells 11, and each battery cell 11 has a shoulder 112. The positive electrode column and the negative electrode column of the battery cell 11 are both arranged on the top surface of the battery cell 11, and the shoulder 112 can be formed on both sides of the battery cell 11 in the width direction.

[0166] The tab 2 is welded, screwed, riveted or bonded with conductive adhesive to the pole 111 of the battery module 1. Therefore, the battery module assembly 100 of the embodiment of the present invention has the advantage of high connection convenience. For example, the tab 2 connecting the battery cells 11 and the battery cells 11 can be connected to the pole 111 of the battery cell 11 by riveting or laser welding, thereby realizing high-voltage series or parallel connection of the entire battery module 1.

[0167] Optionally, the bar piece 2 may be a copper alloy bar piece 2 or an aluminum alloy bar piece 2, and an observation hole is provided on the bar piece 2. Furthermore, the bar piece 2 may be formed by stamping, machining or casting.

[0168] Optionally, the pole 111 may be square or circular. The pole 111 generally includes a positive pole and a negative pole, and the positive pole and the negative pole are arranged on the same end surface of the battery module 1 .

[0169] like Figure 8 As shown, in the length direction of the battery cell 11, the ratio between the length L1 of the pole 111 and the length L3 of the battery cell 11 is 0.1-0.4. In this way, it is avoided that the ratio is too large (exceeding 0.40), and the top surface of the battery cell 11 does not have enough area to accommodate the necessary electrical safety distance between the positive pole and the negative pole of the battery cell 11, resulting in poor safety; and it is avoided that the ratio is too small, which will cause the top surface of the battery cell 11 to be attached to the first liquid cooling plate 3. The area accounts for a small proportion, which in turn leads to the problem of poor heat exchange efficiency at the top of the battery cell 11. Therefore, the battery module assembly 100 has the advantages of good cooling effect and high structural strength.

[0170] Specifically, the positive electrode column and the negative electrode column of the battery cell 11 are both arranged on the same side of the battery cell 11 , and there may also be two or more positive electrode columns and two or more negative electrode columns.

[0171] like Figure 8 As shown, in the width direction of the battery cell 11, the ratio between the width L2 of the pole 111 and the width L4 of the battery cell 11 is 0.1-0.99. Thus, the problem of poor cooling effect caused by the ratio between the width L2 of the pole 111 and the width L4 of the battery cell 11 being too small is avoided, and the problem of installation interference of the first liquid cooling plate 3 caused by the ratio between the width L2 of the pole 111 and the width L4 of the battery cell 11 being too large is avoided. Therefore, the battery module assembly 100 has the advantages of good cooling effect and high installation convenience.

[0172] The ratio of the width L2 of the pole 111 to the width L4 of the battery cell 11 can be 0.1, 0.4 or 0.99. When the ratio of the width L2 of the pole 111 to the width L4 of the battery cell 11 is 0.1, reducing the volume of the pole 111 can allow a larger space between the first liquid cooling plate 3 and the end face of the battery cell, making it easier for the high-temperature material sprayed from the explosion-proof valve 113 to diffuse.

[0173] When the ratio between the width L2 of the pole 111 and the width L4 of the battery cell 11 is 0.99, the end face of the pole 111 has a larger area, which can increase the contact area between the pole 111 and the first liquid cooling plate 3, and increase the heat dissipation rate of the pole 111. In addition, when the first liquid cooling plate 3 extends along the length direction of the battery cell, and two first liquid cooling plates 3 are arranged at intervals along the width direction of the battery cell on each pole 111, the pole 111 has sufficient width to arrange two first liquid cooling plates 3, ensuring that the first liquid cooling plate 3 has sufficient contact area with the pole, improving the cooling effect on the pole, and at the same time, it can meet the requirements of the spatial position between the first liquid cooling plate 3 and the explosion-proof valve 113 as defined in the above embodiment, and effectively suppress the heat spread during thermal runaway of the battery cell.

[0174] When the ratio of the width L2 of the pole 111 to the width L4 of the battery cell 11 is 0.4, more space can be provided between the first liquid cooling plate and the end surface of the battery cell while ensuring sufficient contact area between the pole 111 and the first liquid cooling plate 3 .

[0175] like Figure 8 As shown, in the length direction of the battery cell 11, the ratio of the length of the bar piece 2 to the length L1 of the pole 111 is 0.1-5. Thus, it is possible to avoid the problem of the bar piece 2 interfering with the installation when the ratio of the length of the bar piece 2 to the length L1 of the pole 111 is too large, and to avoid the problem of the bar piece 2 and the pole 111 being too small, which will result in a small proportion of the contact surface between the bar piece 2 and the pole 111, and thus lead to poor electrical connection or heat exchange efficiency of the battery cell 11. Therefore, the battery module assembly 100 has the advantages of good cooling effect and high installation convenience.

[0176] The ratio of the length of the bar 2 to the length L1 of the pole 111 can be 0.1, 1.5 or 5. When the ratio of the length of the bar 2 to the length L1 of the pole 111 is 0.1, the bar can be prevented from interfering with the first liquid cooling plate 3 or other components during installation, and the space between the first liquid cooling plate 3 and the end face of the battery cell can be saved, which is helpful for the eruption and diffusion of high-temperature substances during thermal runaway of the battery cell; when the ratio of the length of the bar 2 to the length L1 of the pole 111 is 5, there is a larger fitting area between the bar 2 and the pole 111, and between the bar 2 and the first liquid cooling plate 3, which can improve the effect of heat transfer and improve the cooling effect of the first liquid cooling plate 3 on the pole 111.

[0177] When the ratio of the length of the bar 2 to the length L1 of the pole 111 is 1.5, it can ensure that there is a larger fitting area between the bar 2 and the pole 111, and between the bar 2 and the first liquid cooling plate 3, while avoiding position interference between the bar 2 and the explosion-proof valve 113, and avoiding the space between the first liquid cooling plate 3 and the end face of the battery cell due to the excessive length of the bar 2.

[0178] Furthermore, the ratio of the length of the bar piece 2 to the length L1 of the pole 111 is 1.5-5. That is, the length of the bar piece 2 is greater than the length of the pole 111. Furthermore, the bar piece 2 includes a connected overlap portion and an extension portion, the overlap portion overlaps the two poles 111 of two adjacent battery cells 11, and the extension portion extends to the shoulder 112 of the battery cell 11, so that the bar piece improves the electrical connection stability between the bar pieces and the heat exchange efficiency between the first liquid cooling plate and the pole without affecting the opening of the explosion-proof valve and the ejection of high-temperature substances.

[0179] like Fig. 9 As shown, in the second direction perpendicular to the first direction and the height direction of the battery cell 11 (that is, when the first direction is the length direction of the battery cell 11, the second direction is the width direction of the battery cell 11; when the first direction is the width direction of the battery cell 11, the second direction is the length direction of the battery cell 11), the ratio of the length L5 of the liquid cooling part 31 to the length L6 of the bar piece 2 is 0.1-2. In this way, the problem of poor cooling effect caused by the ratio of the length of the liquid cooling part 31 to the length of the bar piece 2 being too small is avoided. It also avoids the problem of too large a ratio of the length of the liquid cooling part 31 to the length of the bar piece 2, resulting in a small contact area between the liquid cooling part 31 and the bar piece 2, thereby avoiding the advantage of material waste at the liquid cooling part 31. The ratio of the length L5 of the liquid cooling part 31 to the length L6 of the bar 2 can be 0.1, 1 or 2. When the ratio of the length L5 of the liquid cooling part 31 to the length L6 of the bar 2 is 0.1, the cost of the first liquid cooling plate 3 can be reduced, and the position of the first liquid cooling plate 3 in the second direction can be more flexibly adjusted, and the spatial position relationship between the first liquid cooling plate 3 and the explosion-proof valve 113 can be better adjusted, thereby improving the effect of the first liquid cooling plate 3 in suppressing the spread of heat when the battery cell is thermally runaway. When the ratio of the length L5 of the liquid cooling part 31 to the length L6 of the bar 2 is 2, the contact area between the first liquid cooling plate 3 and the bar 2 can be increased, thereby improving the effect of heat transfer.

[0180] When the ratio of the length of the liquid cooling portion 31 to the length of the bar sheet 2 can be 1, the battery module assembly 100 can achieve better effects in cooling efficiency, cost, and the effect of suppressing the spread of thermal runaway.

[0181] like Figure 4 , Figure 10-Figure 14As shown, in some embodiments, the battery module assembly 100 of the embodiment of the present invention further includes a second liquid cooling plate 4, the second liquid cooling plate 4 is arranged on the battery cell 11, and the second liquid cooling plate 4 is arranged opposite to the first liquid cooling plate 3. It can be understood that the height direction of the second liquid cooling plate 4 and the first liquid cooling plate 3 battery cell 11 (such as Figure 4 The upper and lower directions shown in FIG. 1 are relatively arranged on both sides of the battery cell.

[0182] The battery module assembly 100 of the embodiment of the present invention can cool the other side of the battery module 1 by disposing the second liquid cooling plate 4 on the side of the battery module 1 opposite to the first liquid cooling plate 3. Therefore, the battery module assembly 100 further improves the heat dissipation effect and uniformity of the battery module 1.

[0183] like Fig.13 and Fig.14 As shown, in the embodiment of the present invention, a first cooling channel 311 is provided in the first liquid cooling plate 3 , and a second cooling channel 41 is provided in the second liquid cooling plate 4 . Each of the first cooling channel 311 and the second cooling channel 41 has a cooling medium for cooling the battery module 1 .

[0184] The battery module assembly 100 of the embodiment of the present invention controls the flow path of the cooling medium by providing a first cooling channel 311 in the first liquid cooling plate 3 and a second cooling channel 41 in the second liquid cooling plate 4, thereby extending the time for the cooling medium to flow in the liquid cooling plates (the first liquid cooling plate 3 and the second liquid cooling plate 4) and improving the cooling effect of the liquid cooling plates. As a result, the battery module assembly 100 improves the heat dissipation effect of the battery module 1.

[0185] Optionally, the first liquid cooling plate 3 and the second liquid cooling plate 4 may be in the form of harmonica tubes or may be stamped and brazed.

[0186] Furthermore, the battery module assembly 100 of the embodiment of the present invention also includes a first collector and a second collector, the first cooling channel 311 and the second cooling channel 41 both include a plurality of branch channels extending along the second direction, the first collector is correspondingly arranged at both ends of the extension direction of the first liquid cooling plate 3, and the second collector is correspondingly arranged at both ends of the extension direction of the second liquid cooling plate 4.

[0187] The battery module assembly 100 of the embodiment of the present invention includes a plurality of sub-channels extending along the extension direction of the first liquid cooling plate 3 or the second liquid cooling plate 4 through the first cooling channel 311 and the second cooling channel 41, thereby expanding the area covered by the cooling channel when flowing in the liquid cooling plate, thereby better improving the cooling effect of the liquid cooling plate on the battery module 1. The cooling medium in the sub-channels can be converged by the first and second converging pieces, and there is no need to set a connecting pipe for each sub-channel, thereby improving the convenience of connection and layout.

[0188] like Fig.10 As shown, the battery module assembly 100 of the embodiment of the present invention further includes a liquid inlet pipe 51 and a liquid outlet pipe 52, and the liquid inlet pipe 51, the first liquid cooling plate 3, the liquid outlet pipe 52 and the second liquid cooling plate 4 are connected in sequence.

[0189] The battery module assembly 100 of the embodiment of the present invention connects the first liquid cooling plate 3 and the second liquid cooling plate 4 through the provided liquid inlet pipe 51 and the liquid outlet pipe 52 to realize the circulation of the internal cooling medium, thereby improving the cooling uniformity and control convenience of the battery module 1.

[0190] Alternatively, if Fig.11 As shown, there may be multiple first liquid cooling plates 3, and the first liquid cooling plates 3 may be connected in parallel or in series and then connected to the second liquid cooling plate 4. Fig.12 As shown, the second liquid cooling plate 4 can be a plate structure with a liquid cavity, and the plate structure has a liquid outlet and a liquid inlet. The battery module 1 can have a plurality of rows of cells arranged in a row, each of which can have two shoulders 112, and each shoulder 112 is correspondingly provided with a first liquid cooling plate 3, and the plurality of first liquid cooling plates 3 can be connected in series or in parallel to form a whole and then connected to the second liquid cooling plate 4.

[0191] like Fig.13 As shown, the second liquid cooling plate 4 has a heat exchange panel 42 and a flow channel panel 43 arranged relatively along the height direction of the battery cell 11, and the heat exchange panel 42 and the flow channel panel 43 form a second cooling flow channel 41. The fitting area between the heat exchange panel 42 and the battery module 1 is S1, and the area of ​​the battery module 1 and the heat exchange panel 42 on the side connected is S2, and the ratio of S1 to S2 is 0.1-1. In this way, the problem of poor cooling effect caused by the small heat exchange area of ​​the second liquid cooling plate 4 can be avoided, and the problem of the heat exchange panel 42 being too large to occupy the internal space of the battery pack 1000 can be avoided.

[0192] like Fig.13 As shown, in some embodiments, in the height direction of the battery cell 11, the thickness of the heat exchange panel 42 is D1, the size of the second cooling channel 41 is H1, 0.02≤D1 / H1≤5; the thickness of the channel panel 43 is D2, the size of the second cooling channel 41 is H1, 0.02≤D2 / H1≤5. As a result, the battery module assembly 100 avoids the problem of poor cooling effect caused by the excessive thickness of the heat exchange panel 42 and / or the channel panel 43 occupying the space of the second cooling channel 41, and avoids the problem of weak structural strength caused by the excessive thickness of the heat exchange panel 42 and / or the channel panel 43. Therefore, the battery module assembly 100 has the advantages of good cooling effect and high structural strength.

[0193] The ratio of D1 / H1 can be 0.02, 2 or 5. When the ratio of D1 / H1 is 0.02, the thickness ratio of the heat exchange panel 42 can be reduced to avoid occupying the space of the second cooling channel 41, and the cooling effect of the cooling medium in the channel and the battery cell can be improved. It can also save space in the height direction of the battery cell to increase the power density of the battery and save the material cost of the second liquid cooling plate 4. When the ratio of D1 / H1 is 5, the structural strength of the heat exchange panel can be improved. When the ratio of D1 / H1 is 2, the heat exchange panel 42 can have the advantages of good cooling effect, cost saving and high structural strength.

[0194] The ratio of D2 / H1 can be 0.02, 3 or 5. When the ratio of D2 / H1 is 0.02, the thickness ratio of the flow channel panel 43 can be reduced to avoid occupying the space of the second cooling flow channel 41, improve the cooling effect, and save space in the height direction of the battery cell to improve the power density of the battery and save material costs. When the ratio of D2 / H1 is 5, the structural strength of the heat exchange panel can be improved to avoid deformation of the flow channel panel 43 after being squeezed or collided. When the ratio of D2 / H1 is 3, the flow channel panel 43 can have the advantages of good cooling effect, cost saving and high structural strength.

[0195] Optionally, the heat exchange panel 42 may be a flat panel, and the flow channel panel 43 may be a corrugated structured panel. The heat exchange panel 42 and the flow channel panel 43 may be formed into the second liquid cooling plate 4 by stamping, brazing, and inflation manufacturing, and the second liquid cooling plate 4 may also be a harmonica tube or an aluminum profile tube.

[0196] Optionally, in order to ensure the connection strength between the second liquid cooling plate 4 and the battery module 1 and further improve the cooling effect between the second liquid cooling plate 4 and the battery module 1, various heat exchange media such as thermal pads, thermal conductive adhesives, structural adhesives, double-sided adhesives, etc. can be used between the second liquid cooling plate 4 and the battery module 1 to increase heat conduction.

[0197] like Fig.14 As shown, in the height direction of the battery cell 11, the thickness of the side (heat dissipation surface 312) where the first liquid cooling plate 3 is connected to the bar sheet 2 is D3, and the size of the first cooling channel 311 is H2, 0.02≤D3 / H2≤2. As a result, the battery module assembly 100 not only avoids the problem of poor cooling effect caused by the excessive thickness of the first liquid cooling plate 3 occupying the space of the first cooling channel 311, but also avoids the problem of weak structural strength caused by the excessive thickness of the first liquid cooling plate 3. Therefore, the battery module assembly 100 has the advantages of good cooling effect and high structural strength.

[0198] The ratio of D3 / H2 can be 0.02, 1 or 2. When the ratio of D3 / H2 is 0.02, the thickness ratio of the heat dissipation surface 312 can be reduced to avoid occupying the space of the first cooling channel 311, improve the cooling effect, and save space in the height direction of the battery cell to increase the power density of the battery and save the material cost of the first liquid cooling plate 3. When the ratio of D3 / H2 is 2, the structural strength of the heat dissipation surface 312 can be improved to avoid deformation of the heat dissipation surface 312 after being squeezed or collided. When the ratio of D3 / H2 is 1, the heat dissipation surface 312 can have the advantages of good cooling effect, cost saving and high structural strength.

[0199] like Figure 1 As shown, the battery pack 1000 of the embodiment of the present invention comprises a housing 200 and a battery module assembly 100 according to any of the above embodiments disposed in the housing 200. Therefore, the battery pack 1000 of the embodiment of the present invention has the advantages of good fast charging capability and improved heat dissipation capability.

[0200] The vehicle according to the embodiment of the present invention includes the battery module assembly 100 as in any one of the above embodiments, or the battery pack 1000 as in the above embodiments.

[0201] At least some of the beneficial effects achieved by the vehicle of the embodiment of the present invention are the same as or similar to the beneficial effects achieved by the battery module assembly 100 or the battery pack 1000 in the above-mentioned embodiment, so they are not described in detail here.

[0202] The battery module assembly 100 and the battery pack 1000 in the above-mentioned embodiment can be applied to the new energy industry, including but not limited to vehicles.

[0203] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0204] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying 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 the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0205] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0206] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0207] In the present invention, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0208] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A battery module assembly, characterized in that: include: A battery cell, wherein the battery cell has a pole and an explosion-proof valve located on the same end surface in a height direction of the battery cell; A first liquid cooling plate, wherein the first liquid cooling plate is attached above the pole along the height direction of the battery cell; The projections of the first liquid cooling plate and the explosion-proof valve along the height direction of the battery core do not overlap, and at least a portion of the first liquid cooling plate is located within the spraying range of the explosion-proof valve.

2. The battery module assembly according to claim 1, characterized in that: The first liquid cooling plate has a weak area, and the weak area is located within the spray range of the explosion-proof valve; And / or, the first liquid cooling plate is made of a composite material.

3. The battery module assembly according to claim 1, characterized in that: There is a first offset distance between the projection of the first liquid cooling plate and the explosion-proof valve along the height direction of the battery core, and the first offset distance is 0 to 30 mm; And / or, the first liquid cooling plate and the explosion-proof valve have a second offset distance in a height direction of the battery core, and the second offset distance is 0 to 20 mm; And / or, the melting point of the meltable portion of the first liquid cooling plate is less than or equal to 400°C.

4. The battery module assembly according to claim 1, characterized in that: The wall thickness of the meltable portion of the first liquid cooling plate is 0.1 mm to 2 mm; and / or The thermal conductivity of the first liquid cooling plate is greater than or equal to 0.5 W / m·K.

5. The battery module assembly according to any one of claims 1 to 4, characterized in that: The number of the battery cells is multiple, and the multiple battery cells are arranged in an array to form a battery module, the battery module includes at least one battery group arranged along a first direction, the first liquid cooling plate extends along the first direction, and the length of the first liquid cooling plate in the first direction is greater than or equal to the length of the battery group in the first direction; Wherein, the first direction is perpendicular to the height direction of the battery cell.

6. The battery module assembly according to claim 5, characterized in that: The first direction is the length direction of the battery cell, two first liquid cooling plates are attached above one of the poles, the two first liquid cooling plates are arranged at intervals along the width direction of the battery cell, and the explosion-proof valve is located between the two first liquid cooling plates; Alternatively, the first direction is the width direction of the battery cell, and one of the first liquid cooling plates is attached above one of the poles.

7. The battery module assembly according to claim 1, characterized in that: It also includes a bar plate, which is connected to the pole, and the first liquid cooling plate is attached to the bar plate.

8. The battery module assembly according to claim 1, characterized in that: The first liquid cooling plate is connected to the pole via a heat conducting layer.

9. The battery module assembly according to claim 1, characterized in that: It also includes a second liquid cooling plate, which is arranged in close contact with the battery core, and the second liquid cooling plate and the first liquid cooling plate are arranged opposite to each other in the height direction of the battery core.

10. A battery pack, characterized in that: Comprising a battery module assembly as described in any one of claims 1-9.

11. A vehicle, characterized in that: Comprising a battery module assembly as described in any one of claims 1 to 9, or a battery pack as described in claim 10.

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