Battery pack
By incorporating heat-insulating materials and sealant into the exhaust channels within the battery pack, the problem of exacerbated thermal runaway during the smoke exhaust process of lithium-ion battery modules is solved, enabling effective gas extraction and improving the safety and explosion-proof performance of the battery pack.
Patent Information
- Application Number
- CN202423220837.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-24
- Publication Date
- 2026-01-23
- Estimated Expiration
- 2034-12-24
AI Technical Summary
Existing lithium-ion battery modules are prone to short circuits in the acquisition module during smoke exhaust, which can exacerbate thermal runaway and potentially lead to combustion and explosion.
A battery pack is designed to form an exhaust channel by setting a heat insulation material between the bottom of the battery module and the shell, and to use sealant between the side wall and top of the battery module and the shell to prevent gas spread. The exhaust channel formed by the heat insulation material and sealant guides the gas generated during thermal runaway to the bottom to be discharged, avoiding short circuits and excessive pressure.
It effectively prevents gas from accumulating inside the battery pack, reduces the risk of explosion, improves the safety of the battery pack, and prevents the degree of thermal runaway from escalating.
Smart Images
Figure CN223828651U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of battery technology, and more particularly to a battery pack. Background Technology
[0002] Energy storage technology is one of the core technologies driving the world's clean and efficient energy development. Lithium-ion batteries hold a dominant position among them, thanks to their advantages such as low self-discharge rate, long cycle life, and high energy density. However, when lithium-ion batteries are triggered by thermal runaway, they generate a large amount of flammable gas, causing the runaway to spread uncontrollably.
[0003] Most existing lithium-ion battery modules adopt a top exhaust design. Since the exhaust gas itself is not insulating, when the exhaust gas passes through the collection module at the top of the lithium-ion battery, it can easily cause a short circuit in the collection module, which will aggravate the degree of thermal runaway and eventually evolve into events such as combustion and explosion. Utility Model Content
[0004] This application provides a battery pack that addresses the problem of increased thermal runaway during the exhaust process.
[0005] This application provides a battery pack comprising: a housing and a battery module, wherein the battery module is installed inside the housing, the housing has a bottom wall, and an exhaust channel is formed between the bottom of the battery module and the bottom wall by means of a heat-insulating material; and sealant is provided between the side wall of the battery module and the housing, and between the top of the battery module and the housing.
[0006] In one possible design, the battery module includes multiple battery cells, the heat insulation material includes heat insulation elements, the heat insulation elements are disposed between adjacent battery cells, and the bottom of the heat insulation elements extends beyond the bottom of the battery cells along the height direction of the battery cells to form a first sub-channel between adjacent heat insulation elements, and the bottom of the battery cells is disposed facing the first sub-channel.
[0007] In one possible design, the insulation material further includes an insulation board, the insulation member abuts against the insulation board, and a second sub-channel is formed between the insulation board and the bottom wall at an interval; the exhaust channel includes a first sub-channel and a second sub-channel, and the first sub-channel is capable of communicating with the second sub-channel.
[0008] In one possible design, the heat insulation plate is provided with a groove at the position corresponding to the battery cell, and the groove corresponds to the position of the first sub-channel, so that the gas and / or substances generated by the battery cell during thermal runaway will destroy the heat insulation plate, thereby connecting the first sub-channel and the second sub-channel.
[0009] In one possible design, the insulation panel has fewer mica layers in the area where the groove is formed than it has outside the area where the groove is formed.
[0010] In one possible design, a support member extending along the thickness direction of the battery cell is provided on the bottom wall. The support member is located between the bottom wall and the heat insulation plate and abuts against the heat insulation plate to support the heat insulation plate.
[0011] In one possible design, along the width direction of the battery cell, support steps protruding into the interior of the housing are provided on both sides of the housing, and the support steps provide support and limit the battery module.
[0012] In one possible design, the portion of the insulation extending beyond the bottom of the battery cell is provided with a limiting recess, and the support step is capable of engaging with the limiting recess.
[0013] In one possible design, a baffle strip extending along the thickness direction of the battery cell is provided on the support step, and the baffle strip abuts against the battery cell and the heat insulation component.
[0014] In one possible design, the width of the adhesive strip is smaller than the width of the limiting recess along the width direction of the battery cell.
[0015] In this application, the gas generated during thermal runaway of the battery pack can be discharged through the exhaust channels, preventing gas accumulation and excessive pressure within the battery pack that could lead to an explosion. Because the exhaust channels are spaced apart by thermal insulation material between the bottom and bottom wall of the battery module, and the sealant between the side wall and the casing of the battery module prevents the gas generated during thermal runaway from spreading outwards from the side wall of the battery module, and the sealant on the top of the battery module prevents the gas generated during thermal runaway from spreading outwards from the top of the battery module, the gas flows towards the exhaust channels at the bottom of the battery module. This prevents the gas from spreading to the top of the battery module and short-circuiting the acquisition module, thus avoiding exacerbating the thermal runaway.
[0016] It should be understood that the above general description and the following detailed description are merely exemplary and do not limit this application. Attached Figure Description
[0017] Figure 1 This is a schematic diagram of the structure of the battery pack provided in this application in a specific embodiment;
[0018] Figure 2 for Figure 1 A sectional view;
[0019] Figure 3 for Figure 1A cross-sectional view from another perspective;
[0020] Figure 4 for Figure 3 A magnified view of a portion of region I;
[0021] Figure 5 for Figure 3 Schematic diagram of the structure of the battery cell and thermal insulation component;
[0022] Figure 6 for Figure 3 Schematic diagram of the structure of the heat insulation panel;
[0023] Figure 7 for Figure 1 A schematic diagram of the structure of the battery pack excluding the battery module;
[0024] Figure 8 for Figure 7 A magnified view of a portion of region II.
[0025] Figure label:
[0026] 1-Shell;
[0027] 1a - First sub-channel;
[0028] 1b - Second sub-channel;
[0029] 11-First sidewall;
[0030] 12-Second sidewall;
[0031] 13-Supporting steps;
[0032] 14-Bottom wall;
[0033] 2-Battery module;
[0034] 21-cell;
[0035] 22-Insulation components;
[0036] 221-limiting recess;
[0037] 3-Insulation board;
[0038] 31-groove;
[0039] 4-Supporting components;
[0040] 5-Blood-blocking strip;
[0041] 6-Explosion-proof valve;
[0042] 7-Sealant.
[0043] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. Detailed Implementation
[0044] To better understand the technical solution of this application, the embodiments of this application will be described in detail below with reference to the accompanying drawings.
[0045] It should be understood that the described embodiments are merely some, not all, of the embodiments in this application. All other embodiments obtained by those skilled in the art based on the embodiments in this application without inventive effort are within the scope of protection of this application.
[0046] The terminology used in the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. The singular forms “a,” “the,” and “the” used in the embodiments of this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.
[0047] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.
[0048] It should be noted that the directional terms such as "upper," "lower," "left," and "right" described in the embodiments of this application are used to describe the angles shown in the accompanying drawings and should not be construed as limiting the embodiments of this application. Furthermore, in the context, it should be understood that when it is mentioned that an element is connected "upper" or "lower" to another element, it can be directly connected to the other element "upper" or "lower," or indirectly connected to the other element "upper" or "lower" through an intermediate element.
[0049] This application provides a battery pack, such as... Figure 1 and Figure 2 As shown, the battery pack includes: a housing 1 and a battery module 2. The battery module 2 is installed inside the housing 1. The housing 1 has a bottom wall 14. A venting channel is formed between the bottom of the battery module 2 and the bottom wall 14 by means of heat insulation material. There is sealant 7 between the side wall of the battery module 2 and the housing 1 and between the top of the battery module 2 and the housing 1.
[0050] The battery module 2 has a data acquisition module (not shown in the figure) on its top. The data acquisition module is used to collect information such as temperature and voltage of the battery module 2 in order to monitor the information of the battery module 2.
[0051] In this embodiment, such as Figure 1 and Figure 2 As shown, the gas generated during thermal runaway of the battery pack can be discharged through the exhaust channels, preventing gas accumulation and excessive pressure within the battery pack that could lead to an explosion. Because the exhaust channels are spaced apart by thermal insulation material between the bottom of the battery module 2 and the bottom wall 14, and the sealant 7 between the side wall of the battery module 2 and the housing 1 prevents the gas generated during thermal runaway from spreading outwards from the side wall of the battery module 2, and the sealant 7 on the top of the battery module 2 prevents the gas generated during thermal runaway from spreading outwards from the top of the battery module 2, the gas flows towards the exhaust channels at the bottom of the battery module 2. This prevents the gas from spreading to the top of the battery module 2 and short-circuiting with the acquisition module, thus preventing the exacerbation of thermal runaway and improving the safety of the battery pack.
[0052] The sealant 7 between the sidewall of the battery module 2 and the housing 1, and the sealant 7 between the top of the battery module 2 and the housing 1, can be formed by injecting sealant into the housing 1 after the battery module 2 is installed into the housing 1. Optionally, sealant can be injected into the housing 1 from the top, side, or other directions.
[0053] Specifically, such as Figure 3 and Figure 4 As shown, the battery module 2 includes multiple battery cells 21, and the heat insulation material includes heat insulation components 22. Heat insulation components 22 are disposed between adjacent battery cells 21. Along the height direction of the battery cell 21, the bottom of the heat insulation component 22 extends beyond the bottom of the battery cell 21, so that a first sub-channel 1a is formed between adjacent heat insulation components 22. The bottom of the battery cell 21 is disposed facing the first sub-channel 1a.
[0054] Furthermore, the heat insulation material also includes a heat insulation board 3, the heat insulation component 22 abuts against the heat insulation board 3, and the heat insulation board 3 is spaced apart from the bottom wall 14 to form a second sub-channel 1b; the exhaust channel includes a first sub-channel 1a and a second sub-channel 1b, and the first sub-channel 1a can communicate with the second sub-channel 1b.
[0055] like Figure 4 As shown, Figure 4The red dashed arrows in the diagram indicate one direction of gas flow in the exhaust channel. Gas generated by cell 21 during thermal runaway can be directly discharged into the first sub-channel 1a, and then into the second sub-channel 1b. An explosion-proof valve 6 is provided on the bottom wall 14 of the housing 1. One end of the explosion-proof valve 6 is connected to the second sub-channel 1b, and the other end is connected to the outside. When the pressure inside the battery pack is lower than the threshold of the explosion-proof valve 6, the explosion-proof valve 6 closes, blocking the connection between the second sub-channel 1b and the outside; when the pressure inside the battery pack is higher than the threshold of the explosion-proof valve 6, the explosion-proof valve 6 opens, connecting the second sub-channel 1b to the outside, allowing gas in the second sub-channel 1b to be discharged from the housing 1 to the outside. Preferably, the explosion-proof valve 6 is located at the center of the bottom wall 14 to facilitate the discharge of gas from the second sub-channel 1b. It is understood that the explosion-proof valve 6 can also be located at other positions on the bottom wall 14 besides the center.
[0056] It should be understood that the bottom here is described in terms of position relative to cell 21, and is not related to the orientation of the battery pack in use.
[0057] More specifically, multiple battery cells 21 can be stacked along the thickness direction of the battery cell 21, such that the first sub-channel 1a is spaced apart along the thickness direction of the battery cell 21, and the second sub-channel 1b extends along the thickness direction of the battery cell 21, so that multiple first sub-channels 1a can be connected to the second sub-channel 1b, and the gas in multiple first sub-channels 1a can be discharged into the second sub-channel 1b.
[0058] like Figure 3 and Figure 5 As shown, the heat insulation component 22 is in contact with the main body of the battery cell 21, which can block the transfer of heat between adjacent battery cells 21. Therefore, when a group of battery cells 21 experiences thermal runaway, it is not easy to cause adjacent battery cells 21 to also experience thermal runaway. This effectively controls the degree of thermal runaway, prevents thermal runaway from causing combustion and explosion, and improves the safety of the battery pack.
[0059] Preferably, the heat insulation element 22 is tightly fitted to the battery cell 21 to prevent gas generated by the battery cell 21 during thermal runaway from spreading upward through the gap between the heat insulation element 22 and the battery cell 21.
[0060] Optionally, the thermal insulation component 22 can be an aerogel felt. Aerogel felt is a thermal insulation material made primarily of aerogel, combined with carbon fiber, ceramic glass fiber cotton, or pre-oxidized fiber felt. It has the advantages of low thermal conductivity and light weight. It is understood that the thermal insulation component 22 can also be made of other materials with low thermal conductivity, which are not listed in this embodiment.
[0061] Optionally, the insulation component 22 also includes foam, which is bonded to aerogel felt, so that the insulation component 22 can also buffer the battery cell 21.
[0062] Furthermore, such as Figure 3 and Figure 4 As shown, a groove 31 is provided at the position of the heat insulation plate 3 corresponding to the position of the battery cell 21. The groove 31 corresponds to the position of the first sub-channel 1a, so that the gas and / or substances generated by the battery cell 21 during thermal runaway will damage the heat insulation plate 3, thereby connecting the first sub-channel 1a and the second sub-channel 1b.
[0063] The heat insulation component 22, the heat insulation plate 3, the peripheral wall of the housing 1, and the battery cell 21 form a sealed first sub-channel 1a. When the battery cell 21 does not experience thermal runaway, the heat insulation plate 3 prevents the first sub-channel 1a from communicating with the second sub-channel 1b. When a battery cell 21 experiences thermal runaway, the gas and substances generated by the battery cell 21 only disrupt the groove 31 of the heat insulation plate 3 below it, allowing the first sub-channel 1a below it to communicate with the second sub-channel 1b. The first sub-channel 1a below other battery cells 21 that have not experienced thermal runaway remains disconnected from the second sub-channel 1b. This prevents the gas and substances from spreading into the first sub-channel 1a below other battery cells 21 that have not experienced thermal runaway, thereby effectively controlling the degree of thermal runaway, preventing its escalation, and greatly improving the safety of the battery pack.
[0064] In other words, the location of the groove 31 on the heat insulation plate 3 has a smaller thickness, resulting in lower strength at that point. This allows the gas or high-temperature jet ejected from the battery cell 21 during thermal runaway to more easily damage the groove 31 portion of the heat insulation plate 3 below it, thus connecting the first sub-channel 1a with the second sub-channel 1b. Simultaneously, by providing the groove 31 on the heat insulation plate 3, the area of damage to the heat insulation plate 3 by gas or substances during thermal runaway is more defined, preventing a larger area of damage from gas or substances. This avoids the situation where the first sub-channel 1a below an adjacent battery cell 21 that has not experienced thermal runaway also connects with the second sub-channel 1b, thereby exacerbating the degree of thermal runaway.
[0065] Specifically, the heat insulation plate 3 has fewer mica layers in the area where the groove 31 is provided than it has outside the area where the groove 31 is provided.
[0066] For example, the heat insulation board 3 has a layer of mica sheet in the area where the groove 31 is provided, and multiple layers of mica sheet in the area where the groove 31 is not provided, thereby achieving a thinner thickness and lower strength at the groove 31 location and a thicker thickness and higher strength at the non-groove 31 location. The mica sheet possesses fire-resistant and insulating properties.
[0067] In one specific implementation, such as Figure 7 and Figure 8As shown, a support member 4 extending along the thickness direction of the battery cell 21 is provided on the bottom wall 14. The support member 4 is located between the bottom wall 14 and the heat insulation plate 3, and abuts against the heat insulation plate 3 to support the heat insulation plate 3. The support member 4 creates a gap between the heat insulation plate 3 and the bottom wall 14, which is the second sub-channel 1b.
[0068] Preferably, two support members 4 are provided, and the two support members 4 are spaced apart below the two ends of the heat insulation plate 3 along the extension direction of the groove 31 to stably support the heat insulation plate 3. It is understood that multiple support members 4 can also be provided. The lengths of the multiple support members 4 can be the same or different. The multiple support members 4 can be evenly distributed below the heat insulation plate 3 or unevenly distributed below the heat insulation plate 3.
[0069] Specifically, the shell 1 can be made of aluminum profile, and the support 4 can also be made of aluminum profile. Because aluminum profile has high structural strength, the support 4 can provide better support for the heat insulation board 3.
[0070] In one specific implementation, such as Figure 7 and Figure 8 As shown, along the width direction of the cell 21, there are support steps 13 protruding into the inside of the housing 1 on both sides of the housing 1. The support steps 13 provide support and limit the battery module 2, preventing the weight of the battery module 2 from being fully applied to the heat insulation plate 3, which would cause the heat insulation plate 3 to be compressed and damaged.
[0071] Specifically, the shell 1 also has opposing first sidewalls 11 and second sidewalls 12 on both sides. One end of the supporting step 13 is connected to the first sidewall 11, and the other end is connected to the second sidewall 12. The distance between the two first sidewalls 11 is greater than the distance between the two second sidewalls 12.
[0072] More specifically, such as Figure 2 and Figure 5 As shown, the portion of the heat insulation member 22 extending beyond the bottom of the protruding battery cell 21 is provided with a limiting recess 221, and the supporting step 13 can cooperate with the limiting recess 221. The width of the portion of the heat insulation member 22 in contact with the battery cell 21 is greater than the width of the portion of the heat insulation member 22 extending beyond the bottom of the protruding battery cell 21, that is, the width of the portion of the heat insulation member 22 in contact with the battery cell 21 is greater than the distance between the two second sidewalls 12, and the width of the portion of the heat insulation member 22 extending beyond the bottom of the protruding battery cell 21 is less than the distance between the two second sidewalls 12, so that the supporting step 13 can limit and position the heat insulation member 22.
[0073] In addition, by filling the gap between the battery module 2 and the first side wall 11 with sealant 7, it can be ensured that when thermal runaway occurs in the battery cell 21, the gas and substances generated by the battery cell 21 will not spread outward from the side of the battery cell 21, but will be discharged from the exhaust channel.
[0074] Furthermore, a sealant-blocking strip 5 extending along the thickness direction of the battery cell 21 is provided on the support step 13. The sealant-blocking strip 5 abuts against the battery cell 21 and the heat insulation component 22, and can support the battery cell 21 and the heat insulation component 22. At the same time, when the sealant is injected into the housing 1, the sealant-blocking strip 5 can prevent the sealant 7 from extending into the first sub-channel 1a and the second sub-channel 1b, so as to prevent the sealant 7 from blocking the exhaust channel.
[0075] Specifically, two sealant strips 5 are provided, each positioned on one of the two support steps 13, preventing the sealant 7 from flowing into the exhaust channel from both sides of the battery module 2. The sealant strips 5 can be made of polyurethane (PU) foam or chloroprene rubber (CR) foam; understandably, they can also be made of other materials.
[0076] Preferably, along the width direction of the cell 21, the width of the seal strip 5 is smaller than the width of the limiting recess 221, that is, there is a gap between the seal strip 5 and the second side wall 12, so that during the injection of adhesive, some of the adhesive can flow to a part of the bottom of the battery module, thereby better preventing the gas and substances generated during thermal runaway of the cell 21 from spreading outward from both sides of the cell 21.
[0077] In the above embodiments, the housing 1 may include two parts: an upper cover and a bottom cover, to facilitate the assembly of the battery pack.
[0078] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.
Claims
1. A battery pack, characterized in that, The battery pack includes a housing (1) and a battery module (2), the battery module (2) being installed inside the housing (1), the housing (1) having a bottom wall (14), and an exhaust channel being formed between the bottom of the battery module (2) and the bottom wall (14) by means of heat insulation material. There is sealant (7) between the side wall of the battery module (2) and the housing (1) and between the top of the battery module (2) and the housing (1).
2. The battery pack according to claim 1, characterized in that, The battery module (2) includes multiple battery cells (21), and the heat insulation material includes a heat insulation component (22), with the heat insulation component (22) disposed between adjacent battery cells (21). Along the height direction of the cell (21), the bottom of the heat insulation member (22) extends beyond the bottom of the cell (21) to form a first sub-channel (1a) between adjacent heat insulation members (22); the bottom of the cell (21) is disposed facing the first sub-channel (1a).
3. The battery pack according to claim 2, characterized in that, The heat insulation material also includes a heat insulation plate (3), the heat insulation component (22) abuts against the heat insulation plate (3), and a second sub-channel (1b) is formed between the heat insulation plate (3) and the bottom wall (14). The exhaust passage includes a first sub-passage (1a) and a second sub-passage (1b), wherein the first sub-passage (1a) is connected to the second sub-passage (1b).
4. The battery pack according to claim 3, characterized in that, The heat insulation plate (3) is provided with a groove (31) at the position corresponding to the battery cell (21). The groove (31) corresponds to the position of the first sub-channel (1a), so that the gas and / or substances generated by the battery cell (21) during thermal runaway will damage the heat insulation plate (3) and make the first sub-channel (1a) and the second sub-channel (1b) connected.
5. The battery pack according to claim 4, characterized in that, The heat insulation plate (3) has fewer mica layers in the area where the groove (31) is provided than it has outside the area where the groove (31) is provided.
6. The battery pack according to claim 3, characterized in that, A support member (4) extending along the thickness direction of the battery cell (21) is provided on the bottom wall (14). The support member (4) is located between the bottom wall (14) and the heat insulation plate (3) and abuts against the heat insulation plate (3) to support the heat insulation plate (3).
7. The battery pack according to any one of claims 2-6, characterized in that, Along the width direction of the cell (21), the two sides of the housing (1) are provided with support steps (13) protruding into the housing (1), and the support steps (13) provide support and limit the battery module (2).
8. The battery pack according to claim 7, characterized in that, The heat insulation member (22) extends beyond the bottom of the cell (21) and is provided with a limiting recess (221), and the support step (13) can cooperate with the limiting recess (221).
9. The battery pack according to claim 8, characterized in that, A baffle strip (5) extending along the thickness direction of the battery cell (21) is provided on the support step (13), and the baffle strip (5) abuts against the battery cell (21) and the heat insulation member (22).
10. The battery pack according to claim 9, characterized in that, Along the width direction of the battery cell (21), the width of the rubber strip (5) is smaller than the width of the limiting recess (221).