Battery pack

Abstract

The utility model provides a battery pack. The battery pack comprises an upper cover plate and a heat insulation plate, the upper cover plate is provided with a vent hole corresponding to the explosion-proof valve of the battery cell; a heat insulation plate is arranged between the adjacent battery modules, and the height of the heat insulation plate is greater than that of the battery structure body covered with the upper cover plate. According to the battery pack, the vent holes are formed in the positions, corresponding to the anti-explosion valves of the battery cells, of the upper cover plate, so that high-temperature gas and high-temperature electrolyte generated by the battery cells can be smoothly discharged out of the battery pack after thermal runaway of the battery cells, the electrolyte can be prevented from being splashed to Busbars (busbars and busbars), and spreading of thermal runaway is restrained to a certain extent. On the other hand, the heat insulation plates are arranged between the adjacent battery modules, so that electrolyte splashing from one row of battery modules to other adjacent rows of battery modules can be reduced to a certain extent, the electrolyte splashing path is increased, and the electrolyte splashing spreading time is prolonged; therefore, the battery pack in the scheme can effectively restrain the spreading of thermal runaway.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a battery pack. Background Art

[0002] Existing battery packs cannot effectively contain the spread of flames, high-temperature gases and electrolytes when thermal runaway, overcharging or over-discharging occurs, and the spread time is very short, so it will cause more serious consequences.

[0003] Therefore, there is an urgent need for a battery pack that can solve the technical problems existing in the prior art to a certain extent. Utility Model Content

[0004] The purpose of this application is to provide a battery pack that can curb the spread of thermal runaway to a certain extent.

[0005] The present application provides a battery pack, comprising a battery structure, a side plate and an epoxy plate; the battery structure comprises a plurality of battery modules arranged along a first direction, each of the battery modules comprises a plurality of battery cells arranged along a second direction; the side plates are attached to the side walls at both ends of the battery structure along the first direction, and the epoxy plate is arranged on the side walls at both ends of the battery structure along the second direction; the battery pack further comprises an upper cover plate and a heat insulation plate;

[0006] The upper cover plate covers the top of the battery structure, and the upper cover plate is provided with a vent hole corresponding to the explosion-proof valve of the battery cell;

[0007] A heat insulation board is arranged between adjacent battery modules, and the height of the heat insulation board is greater than the height of the battery structure covered with the upper cover plate.

[0008] In the above technical solution, further, the battery pack also includes a steel tie, the steel tie is wound around the circumferential side wall of the battery structure, and the surface of the steel tie is coated with an insulating layer.

[0009] In the above technical solution, further, the steel tie is wrapped with a mica tape layer at the bending part of the battery structure.

[0010] In the above technical solution, further, the height of the heat insulation board is higher than the height of the battery structure covered with the upper cover plate and is set in the range of 2-10 mm.

[0011] In the above technical solution, further, an aerogel layer is provided between adjacent battery cells;

[0012] A composite MPP strip is arranged on one side of the aerogel layer facing the battery core, and the composite MPP strip is respectively arranged at two ends of the aerogel layer along the third direction, so that a heat-conducting gap is provided between adjacent battery cores.

[0013] In the above technical solution, further, the battery pack also includes an end plate;

[0014] The end plate is arranged on a side of the epoxy plate away from the battery cell structure;

[0015] Two ends of the side plate along the second direction are fixed to the end plate through a buckle structure.

[0016] In the above technical solution, further, the buckle structure includes a protrusion and a limiting column;

[0017] The protrusions are arranged at two ends of the side plate along the second direction, and the protrusions are provided with limiting holes;

[0018] The limiting posts are arranged at two ends of the end plate along the first direction, and the limiting posts can be inserted into the limiting holes to fix the side plate to the end plate.

[0019] In the above technical solution, further, the battery pack also includes a ceramic silicone rubber protective layer;

[0020] The size of the end plate is smaller than that of the epoxy plate, a portion of the epoxy plate is exposed from the end plate, and the ceramic silicone rubber protective layer is arranged on the portion of the epoxy plate exposed from the end plate.

[0021] In the above technical solution, further, the ceramic silicone rubber protective layer is a frame structure, including an upper side plate and a side plate; the side plates are respectively arranged at both ends of the upper side plate;

[0022] The upper side plate is attached to the upper edge of the epoxy plate along the third direction, and the side plates are attached to the two side edges of the epoxy plate along the first direction.

[0023] In the above technical solution, further, the side plate is adhered to the side wall of the battery structure by using structural adhesive.

[0024] Compared with the prior art, this application has the following beneficial effects:

[0025] The battery pack provided by the present application, on the one hand, is provided with vent holes at the position of the explosion-proof valve of the battery cell on the upper cover plate, so as to ensure that after the thermal runaway of the battery cell, the high-temperature gas generated by the battery cell can be smoothly discharged to the outside of the battery pack, which can reduce the splashing of electrolyte onto the Busbar (busbar), thereby curbing the spread of thermal runaway to a certain extent. On the other hand, by arranging a heat insulation board between adjacent battery modules, and the height of the heat insulation board is greater than the height of the battery structure covered with the upper cover plate, under the blocking effect of the heat insulation board, the splashing of electrolyte from one row of battery modules to other adjacent rows of battery modules can be reduced to a certain extent, and the setting of the heat insulation board also increases the path of electrolyte splashing, thereby increasing the splashing and spreading time of the electrolyte; therefore, the battery pack of the present scheme reduces the possibility of electrolyte spreading to other positions from multiple directions, and at the same time increases the spreading time of the electrolyte to a certain extent, thereby curbing the spread of thermal runaway. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0027] Figure 1 A schematic diagram of the structure of the battery pack provided in this application at a first viewing angle;

[0028] Figure 2 A schematic diagram of the structure of the battery pack provided in this application at a second viewing angle;

[0029] Figure 3 for Figure 2 A in the enlarged view;

[0030] Figure 4 A schematic diagram of the structure of the hidden side panels, upper cover, and steel tie in the battery pack provided in this application;

[0031] Figure 5 A schematic diagram of the structure of the upper cover plate in the battery pack provided in this application;

[0032] Figure 6 A schematic diagram of the structure of the side plate in the battery pack provided in this application;

[0033] Figure 7 A schematic diagram of the structure of the steel cable tie in the battery pack provided in this application;

[0034] Figure 8 A schematic diagram of the structure of the hidden battery cell in the battery pack provided in this application;

[0035] Fig. 9 A schematic diagram of the structure of the aerogel and composite MPP strips in the battery pack provided in this application;

[0036] Fig.10 This is a schematic diagram of the structure of the ceramic silicone rubber protective layer in the battery pack provided in this application.

[0037] Figure numerals: 1-battery structure; 2-side panel; 3-epoxy panel; 4-first direction; 5-battery module; 6-second direction; 7-battery cell; 8-upper cover; 9-steel tie; 10-insulation board; 11-vent; 12-mica tape layer; 13-aerogel layer; 14-composite MPP strip; 15-third direction; 16-ceramic silicone rubber protective layer; 17-insulating layer; 18-end plate; 20-protrusion; 21-limiting column; 22-limiting hole; 23-upper side panel; 24-side panel. DETAILED DESCRIPTION

[0038] The following specific embodiments are provided to help the reader obtain a comprehensive understanding of the methods, devices and / or systems described herein. However, after understanding the disclosure of the present application, various changes, modifications and equivalents of the methods, devices and / or systems described herein will be apparent. For example, the order of operations described herein is merely an example, which is not limited to the order set forth herein, but in addition to the operations that must occur in a specific order, changes that will be apparent after understanding the disclosure of the present application can be made. In addition, in order to improve clarity and brevity, the description of features known in the art can be omitted. The features described herein can be implemented in different forms and should not be construed as being limited to the examples described herein. More specifically, the examples described herein have been provided only to illustrate some of the many possible ways of implementing the methods, devices and / or systems described herein that will be apparent after understanding the disclosure of the present application. Throughout the specification, when an element (such as a layer, region, or substrate) is described as being "on" another element, "connected to" another element, "bonded to" another element, "on" another element, or "covering" another element, it may be directly "on" another element, "connected to" another element, "bonded to" another element, "on" another element, or "covering" another element, or there may be one or more other elements between them. In contrast, when an element is described as being "directly on" another element, "directly connected to" another element, "directly bonded to" another element, "directly on" another element, or "directly covering" another element, there may be no other elements between them. As used herein, the term "and / or" includes any one of the listed related items and any combination of any two or more items. Although terms such as "first", "second", and "third" may be used here to describe individual components, assemblies, regions, layers, or parts, these components, assemblies, regions, layers, or parts are not limited by these terms. More precisely, these terms are only used to distinguish a member, component, region, layer or part from another member, component, region, layer or part. Therefore, without departing from the teaching of the example, the first member, component, region, layer or part referred to in the example described here may also be referred to as the second member, component, region, layer or part. For ease of description, spatial relationship terms such as "above ... ", "upper", "below ... " and "lower" can be used here to describe the relationship between an element and another element as shown in the drawings. Such spatial relationship terms are intended to include different orientations of the device in use or operation in addition to being included in the orientation depicted in the drawings. For example, if the device in the drawings is flipped, the element described as being "above" or "upper" relative to another element will then be located "below" or "lower" relative to another element.Therefore, the term "above" includes two orientations, "above" and "below" according to the spatial orientation of the device. The device can also be positioned in other ways (for example, rotated 90 degrees or in other orientations), and the spatial relationship terms used here will be interpreted accordingly. The terms used here are only used to describe various examples and are not used to limit the present disclosure. Unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. The terms "include", "comprise" and "have" list the stated features, quantities, operations, components, elements and / or their combinations, but do not exclude the existence or addition of one or more other features, quantities, operations, components, elements and / or their combinations. Due to manufacturing technology and / or tolerances, changes in the shapes shown in the drawings may occur. Therefore, the examples described here are not limited to the specific shapes shown in the drawings, but include changes in shapes that occur during manufacturing. The features of the examples described here can be combined in various ways that will be obvious after understanding the disclosure of the present application. In addition, although the examples described here have various configurations, other configurations are possible as will be obvious after understanding the disclosure of the present application.

[0039] Combine the following Figure 1-Figure 10 , a battery pack provided by the present application is described in detail.

[0040] In this embodiment, a battery pack is provided. The battery pack includes a battery structure 1 , a side plate 2 , and an epoxy plate 3 .

[0041] Among them, see Figure 4 Combined with Figure 1 As shown, the battery structure 1 includes a plurality of battery modules 5 arranged along a first direction 4. Figure 1 The first direction 4 refers to the front-to-back direction. As an example, Figure 1 , a battery pack is shown including a structure of two battery modules 5 , and the two battery modules 5 are arranged along a first direction 4 .

[0042] Continue to see Figure 4 Combined with Figure 1 As shown, each battery module 5 includes a plurality of battery cells 7 arranged along the second direction 6; Figure 1 The second direction 6 refers to the left-right direction, that is, the multiple battery cells 7 are first arranged along the second direction 6 to form the battery module 5, and then the battery module 5 is arranged along the first direction 4 to form the battery structure 1.

[0043] See also Figure 1 As shown, the side panels 2 are attached to the side walls of the battery structure 1 at both ends along the first direction 4, and the epoxy panels 3 are disposed on the side walls of the battery structure 1 at both ends along the second direction 6. Preferably, the side panels 2 are attached to the side walls of the battery structure 1 using structural adhesive.

[0044] In this embodiment, the battery pack further includes an upper cover plate 8 , a steel tie 9 and a heat insulation plate 10 .

[0045] Specifically, see Figure 5 Combined with Figure 1 As shown, the upper cover plate 8 covers the top of the battery structure 1, and the upper cover plate 8 is provided with a vent hole 11 at the explosion-proof valve corresponding to the battery cell 7; Figure 4 As shown, an explosion-proof valve is provided on the top of each battery cell 7. The structure of the explosion-proof valve is a prior art and can be understood by those skilled in the art, so it will not be elaborated on here. When the battery has thermal runaway, overcharge or over-discharge, the explosion-proof valve is activated to relieve pressure and exhaust gas. In the present application, a vent hole 11 is provided on the upper cover plate 8 at a position corresponding to the explosion-proof valve to ensure that after the battery cell 7 has thermal runaway, the gas discharged from the explosion-proof valve can be discharged to the outside of the battery pack through the vent hole 11, thereby achieving smooth exhaust of high-temperature gas. At the same time, the high-temperature electrolyte can also be effectively discharged from the vent hole 11, which can reduce the splashing of the electrolyte onto the Busbar to a certain extent, thereby curbing the spread of thermal runaway.

[0046] Preferably, the upper cover plate 8 and the side plate 2 are both made of mica. The upper cover plate 8 and the side plate 2 made of mica can prevent the flame from burning the side of the battery module 5 after thermal runaway and causing a short circuit.

[0047] Combination Figure 1 and Figure 7 As shown, the steel tie 9 is wrapped around the circumferential side wall of the battery structure 1, the surface of the steel tie 9 is covered with an insulating layer 17, and the steel tie 9 is wrapped with a mica tape layer 12 at the bending part of the battery structure 1, which can avoid the short circuit phenomenon caused by the overlap of the steel tie 9 and the battery cell 7 after thermal runaway to a certain extent.

[0048] In addition, combined Figure 1 , Figure 2 as well as Figure 3 As shown, a heat insulation board 10 is arranged between adjacent battery modules 5, and the height of the heat insulation board 10 is greater than the height of the battery structure 1 covered with the upper cover plate 8, that is, Figure 3As shown, the top of the heat insulation board 10 protrudes from the upper end surface of the upper cover plate 8. Taking the battery structure 1 shown in this embodiment as an example, which includes two rows of battery modules, a heat insulation board 10 is arranged between the two rows of battery modules. When the first row of battery modules 5 has thermal runaway, the heat insulation board 10 between the two rows of battery modules can play a barrier role, and to a certain extent reduce the electrolyte splashing from the first row of battery modules to the second row of battery modules; in addition, setting the height of the heat insulation board 10 to be higher than the height of the battery structure 1 covered with the upper cover plate 8 can increase the path of the electrolyte splashing between adjacent battery modules and the splashing propagation time of the electrolyte. Specifically, still taking the two rows of battery modules as an example, the barrier of the heat insulation board between the two rows of battery modules Under the action of the heat insulation board 10, the electrolyte of the first row of battery modules needs to climb over the heat insulation board 10 before it can splash to the second row of battery modules, that is, the structural setting of the heat insulation board 10 is higher than the battery structure 1 covered with the upper cover plate 8, which can effectively increase the path of the electrolyte splashing between adjacent battery modules when thermal runaway occurs. Assuming that the electrolyte splashing speed remains unchanged, the splashing spread time of the electrolyte is also increased; therefore, setting the heat insulation board 10 to be higher than the battery structure 1 covered with the upper cover plate 8 can, to a certain extent, curb the spread of flames and electrolytes, prolong the spread time, and provide more favorable time for operators to rescue.

[0049] Preferably, the height of the insulation board 10 is set between 2-10 mm higher than the height of the battery structure 1 covered with the upper cover plate 8, that is, the insulation board 10 is between 2-10 mm higher than the upper end surface of the upper cover plate 8; more preferably, the insulation board 10 is 5 mm higher than the upper end surface of the upper cover plate 8.

[0050] Preferably, the heat insulation board 10 is made of epoxy material.

[0051] In summary, the present application mainly improves the ability of the battery pack to suppress thermal runaway through three dimensions. The first dimension is to open a vent hole 11 on the upper cover plate 8 at the position corresponding to the explosion-proof valve of the battery cell 7. The vent hole 11 can connect the outside with the inside of the battery pack after the battery cell 7 thermally runs away, and the high-temperature gas and electrolyte inside the battery pack can be smoothly discharged from the vent hole. Compared with the existing high-temperature gas and electrolyte that spread inside the battery pack due to the lack of vent holes, the present application can reduce the splashing of electrolyte onto the busbar, thereby curbing the spread of high-temperature gas, flame, and electrolyte inside the battery pack.

[0052] The second dimension is that the steel tie 9 is coated with an insulating layer 17, and at the same time, a mica tape layer 12 is wrapped around the steel tie 9 at the bend of the battery structure 1. The mica tape layer 12 plays an insulating role, which can avoid the short circuit caused by the overlap of the steel tie 9 and the battery cell 7 after thermal runaway.

[0053] In the third dimension, a heat insulation plate 10 is arranged between adjacent battery modules 5 and the height of the heat insulation plate 10 is greater than the height of the battery structure 1 covered with the upper cover plate 8. Such a structural arrangement increases the path of electrolyte splashing between adjacent battery modules and prolongs the splashing and spreading time of the electrolyte between adjacent battery modules.

[0054] Therefore, the battery pack of this embodiment provides thermal runaway protection from multiple aspects, and can effectively curb the spread of thermal runaway.

[0055] In addition, in this embodiment, the combination Figure 8 and Fig. 9 As shown, in the same battery module, an aerogel layer 13 is provided between adjacent battery cells 7; Fig. 9 As shown, a composite MPP (rigid foam) strip is provided on one side of the aerogel layer 13 facing the battery cell 7 , and the composite MPP strips 14 are respectively provided at both ends of the aerogel layer 13 along the third direction 15 , so that a heat conductive gap is provided between adjacent battery cells 7 .

[0056] Specifically, combined Figure 8 As shown, the setting of the composite MPP strip 14 is equivalent to supporting the battery cell 7 away from the aerogel layer 13, so that a thermal conductive gap is formed between the battery cell 7 and the aerogel layer 13. With such a setting, once the battery cell 7 has a thermal runaway problem, the heat can be discharged through this thermal conductive gap, effectively reducing the heat transfer to the adjacent battery cell 7 and curbing the spread of thermal runaway.

[0057] In this embodiment, combined with Figure 3 As shown, the battery pack further includes an end plate 18 ; the end plate 18 is disposed on a side of the epoxy plate 3 facing away from the battery structure 1 .

[0058] Specifically, two ends of the side plate 2 along the second direction 6 are fixed to the end plate 18 through a snap-fit ​​structure.

[0059] Furthermore, combined with Figure 2 and Figure 6 As shown, the snap-fit ​​structure includes a protrusion 20 and a limiting column 21; the protrusion 20 is arranged at both ends of the side plate 2 along the second direction 6, and a limiting hole 22 is opened on the protrusion 20; the limiting column 21 is arranged at both ends of the end plate 18 along the first direction 4, and the limiting column 21 can be inserted into the limiting hole 22 to fix the side plate 2 to the end plate 18.

[0060] In this embodiment, combined with Figure 1 and Fig.10 As shown, the battery pack further includes a ceramic silicone rubber protective layer 16 ; the ceramic silicone rubber protective layer 16 is disposed on the portion of the epoxy plate 3 exposed from the end plate 18 .

[0061] Specifically, the epoxy plate 3 can completely cover both ends of the battery structure 1 along the second direction 6. The size of the end plate 18 is smaller than that of the epoxy plate 3. Therefore, a ceramic silicone rubber protective layer 16 is provided on the portion of the epoxy plate 3 exposed from the end plate 18. The ceramic silicone rubber protective layer 16 prevents direct burning of the battery cell 7 after thermal runaway.

[0062] Furthermore, combined with Fig.10 As shown, the ceramic silicone rubber protective layer 16 is a frame structure, and the ceramic silicone rubber protective layer 16 includes an upper side plate 23 and a side plate 24; the side plates 24 are respectively arranged at both ends of the upper side plate 23. The upper side plate 23 is attached to the edge of the epoxy plate 3 along the length direction, that is, the upper edge of the epoxy plate 3 along the third direction 15, and the side plates 24 on both sides are attached to the edge of the epoxy plate 3 along the width direction, that is, the side edges of the epoxy plate 3 along the first direction 4.

[0063] Furthermore, the epoxy board 3 can prevent the problem of short circuit caused by direct contact between the battery cell 7 and the end plate 18 after thermal runaway, that is, the epoxy board 3 plays a role in protecting the battery cell 7 .

[0064] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A battery pack, comprising a battery structure, a side plate and an epoxy plate; the battery structure comprises a plurality of battery modules arranged along a first direction, each of the battery modules comprises a plurality of battery cells arranged along a second direction; the side plates are attached to the side walls at both ends of the battery structure along the first direction, and the epoxy plate is arranged on the side walls at both ends of the battery structure along the second direction; characterized in that: The battery pack also includes an upper cover plate and a heat insulation plate; The upper cover plate covers the top of the battery structure, and the upper cover plate is provided with a vent hole corresponding to the explosion-proof valve of the battery cell; A heat insulation board is arranged between adjacent battery modules, and the height of the heat insulation board is greater than the height of the battery structure covered with the upper cover plate.

2. The battery pack according to claim 1, characterized in that: The battery pack further comprises a steel tie, which is wound around the circumferential side wall of the battery structure, and the surface of the steel tie is coated with an insulating layer.

3. The battery pack according to claim 2, characterized in that: The steel cable tie is wound with a mica tape layer at the bending part of the battery structure.

4. The battery pack according to claim 1, characterized in that: The height of the heat insulation board is higher than the height of the battery structure covered with the upper cover plate and is set in the range of 2-10 mm.

5. The battery pack according to claim 1, characterized in that: An aerogel layer is provided between adjacent battery cells; A composite MPP strip is arranged on one side of the aerogel layer facing the battery core, and the composite MPP strip is respectively arranged at two ends of the aerogel layer along the third direction, so that a heat-conducting gap is provided between adjacent battery cores.

6. The battery pack according to claim 1, characterized in that: The battery pack also includes an end plate; The end plate is arranged on a side of the epoxy plate away from the battery structure; Two ends of the side plate along the second direction are fixed to the end plate through a buckle structure.

7. The battery pack according to claim 6, characterized in that: The buckle structure includes a protrusion and a limiting column; The protrusions are arranged at two ends of the side plate along the second direction, and the protrusions are provided with limiting holes; The limiting posts are arranged at two ends of the end plate along the first direction, and the limiting posts can be inserted into the limiting holes to fix the side plate to the end plate.

8. The battery pack according to claim 7, characterized in that: The battery pack also includes a ceramic silicone rubber protective layer; The size of the end plate is smaller than that of the epoxy plate, a portion of the epoxy plate is exposed from the end plate, and the ceramic silicone rubber protective layer is arranged on the portion of the epoxy plate exposed from the end plate.

9. The battery pack according to claim 8, characterized in that: The ceramic silicone rubber protective layer is a frame structure, including an upper side plate and a side plate; the side plates are respectively arranged at both ends of the upper side plate; The upper side plate is attached to the upper edge of the epoxy plate along the third direction, and the side plates are attached to the two side edges of the epoxy plate along the first direction.

10. The battery pack according to claim 1, characterized in that: The side panels are adhered to the side walls of the battery structure by using structural adhesive.

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