Battery pack and vehicle

Abstract

The utility model discloses a battery pack and a vehicle, and relates to the technical field of power batteries. The battery pack comprises a plurality of battery units and an energy absorption assembly, each battery unit comprises a plurality of single batteries, and each single battery comprises an anti-explosion valve; an energy absorption part is arranged on one side, facing the battery unit, of the energy absorption assembly, and is configured to absorb sprayed objects when the anti-explosion valve is broken. The battery pack can prevent jets from impacting other structures of the battery pack after the explosion-proof valve is broken, prevent spreading of thermal runaway and reduce the safety risk.

Description

Technical Field

[0001] The utility model relates to the technical field of power batteries, and in particular to a battery pack and a vehicle. Background Art

[0002] With the rapid development of new energy vehicles, the demand for lithium-ion batteries is also increasing. Lithium-ion batteries have the advantages of high operating voltage, high energy density, and long cycle life. However, due to the constraints of the body-in-white, the battery is generally installed on the chassis of the car, on which seats are set, etc. Therefore, the safety performance of the battery is crucial to the development of electric vehicles.

[0003] Thermal runaway of battery cells in battery packs is a common technical problem currently faced by the industry. When a battery cell experiences thermal runaway, it ejects a large amount of high-temperature and high-pressure material through the explosion-proof valve, which can easily impact other structures of the battery pack and cause the thermal runaway to spread, posing a safety risk. Utility Model Content

[0004] The purpose of the utility model is to provide a battery pack and a vehicle, which can prevent the ejected material after the explosion-proof valve ruptures from impacting other structures of the battery pack, prevent the spread of thermal runaway, and reduce safety risks.

[0005] To achieve this purpose, the utility model adopts the following technical solutions:

[0006] A battery pack, comprising:

[0007] A plurality of battery units, each of which comprises a plurality of battery cells, each of which comprises an explosion-proof valve;

[0008] An energy absorbing component is provided with an energy absorbing piece on a side of the energy absorbing component facing the battery unit, and the energy absorbing piece is configured to absorb ejected matter when the explosion-proof valve ruptures.

[0009] As an optional solution for the above-mentioned battery pack, the energy absorbing assembly also includes a support member, a fireproof groove is arranged on the side of the support member facing the explosion-proof valve, the fireproof groove extends along a first direction and passes through the support member, and the energy absorbing member is arranged in the fireproof groove.

[0010] As an optional solution to the above battery pack, the size of the fireproof groove in the second direction is greater than or equal to the size of the explosion-proof valve in the second direction;

[0011] The second direction is perpendicular to the first direction, and the second direction is consistent with the height direction of the support member, and the first direction is consistent with the length direction of the support member.

[0012] As an optional solution of the above battery pack, the battery unit includes a plurality of battery cells stacked along the first direction and / or the second direction; the number of the energy absorbing members corresponds to the number of the battery cells stacked in the second direction of the battery unit; the energy absorbing member extends along the first direction;

[0013] The second direction is perpendicular to the first direction, and the second direction is consistent with the thickness direction of the battery cell.

[0014] As an optional solution of the above battery pack, two adjacent battery cells form a battery module, the energy absorbing component is arranged between the two battery cells of the battery module, and the explosion-proof valves of the battery cells in the two battery cells both face the energy absorbing component.

[0015] As an optional solution of the above battery pack, the energy absorbing member includes a sponge-like structure, a bird's nest-like structure, a fluffy structure or a layered porous structure.

[0016] As an optional solution for the above-mentioned battery pack, the support member includes a vertical baffle portion and two horizontal baffle portions arranged at both ends of the vertical baffle portion, and the vertical baffle portion and the two horizontal baffle portions form an "I"-shaped structure.

[0017] As an optional solution of the above-mentioned battery pack, the battery pack also includes a box body, the box body has a accommodating cavity, the battery unit and the energy absorption assembly are accommodated in the accommodating cavity, and the surface where the explosion-proof valve is located is perpendicular to the bottom surface of the box body.

[0018] As an optional solution of the above battery pack, the bottom plate of the box body is provided with a support beam, and the energy absorption component is fixedly arranged on the support beam; the support beam is provided with a positioning column, and the energy absorption component is provided with a positioning hole, and the positioning column is inserted into the positioning hole;

[0019] Alternatively, the battery pack further comprises an upper box cover, wherein the upper box cover is disposed on the box body to close the accommodating cavity, and the upper box cover is provided with a fixing groove, and the energy absorbing component is partially disposed in the fixing groove.

[0020] A vehicle comprises a vehicle body and the above-mentioned battery pack, wherein the battery pack is arranged in the vehicle body, and the surface where the explosion-proof valve is located is perpendicular to the surface where the vehicle body chassis is located.

[0021] Beneficial effects of the utility model:

[0022] The utility model provides a battery pack and a vehicle. In the battery pack, the explosion-proof valves of multiple battery cells of the battery unit face the energy absorbing member of the energy absorbing assembly. When the battery cell is thermally runaway, the ejected material after the explosion-proof valve ruptures can be absorbed by the energy absorbing member, reducing the impact and avoiding the damage to other components of the battery pack caused by the impact energy after the explosion-proof valve ruptures.

[0023] The battery pack can prevent the ejected material after the explosion-proof valve ruptures from impacting other structures of the battery pack, prevent the spread of thermal runaway, and reduce safety risks. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is an exploded view of the battery pack provided by the utility model;

[0025] Figure 2 It is a structural schematic diagram of a battery unit and an energy absorbing component provided by the utility model;

[0026] Figure 3 yes Figure 2 A partial enlarged view of the middle A;

[0027] Figure 4 is a cross-sectional view of the battery pack provided by the utility model;

[0028] Figure 5 An exploded view of a battery cell provided by the utility model;

[0029] Figure 6 A perspective view of a vehicle provided by the utility model.

[0030] In the figure:

[0031] 1. Box body; 2. Battery unit; 3. Energy absorption component; 4. Upper box cover; 5. Battery pack; 6. Vehicle chassis;

[0032] 11. Accommodating cavity; 12. Support beam; 13. Positioning column; 21. Battery cell; 22. Fixing belt; 31. Support member; 32. Energy absorbing member; 33. Fireproof groove; 41. U-shaped member;

[0033] 211. explosion-proof valve; 212. electrode pole; 213. battery cell assembly; 214. battery casing; 215. maximum surface; 216. electrode pole connector; 217. cover plate; 311. vertical baffle portion; 312. horizontal baffle portion. DETAILED DESCRIPTION

[0034] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0035] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance. Among them, the terms "first position" and "second position" are two different positions.

[0036] Unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection; it can be a mechanical connection or an electrical connection; 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. For ordinary technicians in this field, the specific meanings of the above terms in this utility model can be understood according to specific circumstances.

[0037] Unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include the first feature being in direct contact with the second feature, or may include the first feature being in contact with the second feature through another feature between them instead of being in direct contact. Moreover, a first feature being "above", "above" and "above" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes the first feature being directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0038] The technical solution of the utility model is further explained below with reference to the accompanying drawings and through specific implementation methods.

[0039] With the rapid development of new energy vehicles, the demand for lithium-ion batteries is also increasing. Lithium-ion batteries have the advantages of high operating voltage, high energy density, and long cycle life. This embodiment provides a vehicle, which includes a body and a battery pack, and the battery pack is arranged in the body. However, due to the constraints of the body in white, the battery pack is arranged at the chassis position of the body, and the seats and other structures are arranged above the battery pack. Therefore, the safety performance of the battery is crucial to the development of electric vehicles.

[0040] Thermal runaway of battery cells in battery packs is a common technical problem currently faced by the industry. When a battery cell experiences thermal runaway, it ejects a large amount of high-temperature and high-pressure material through the explosion-proof valve, which can easily impact other structures of the battery pack and cause the thermal runaway to spread, posing a safety risk.

[0041] To solve the above problems, Figure 1 to Figure 3 As shown, the battery pack provided in this embodiment includes a case body 1, multiple battery cells 2 and an energy absorbing assembly 3, the case body 1 has a accommodating cavity 11, the battery cell 2 is arranged in the accommodating cavity 11, the battery cell 2 includes multiple battery cells 21, the battery cell 21 includes an explosion-proof valve 211, the energy absorbing assembly 3 is arranged in the accommodating cavity 11, and an energy absorbing member 32 is provided on the side of the energy absorbing assembly 3 facing the battery cell 2, the explosion-proof valve 211 of the battery cell 21 faces the energy absorbing member 32, the plane where the explosion-proof valve 211 is located is perpendicular to the bottom surface of the case body 1, and the energy absorbing member 32 is configured to absorb the ejected material when the explosion-proof valve 211 ruptures.

[0042] In the battery pack, the box body 1 is used to support and protect the battery unit 2, and the explosion-proof valves 211 of the multiple battery cells 21 of the battery unit 2 are facing the energy absorbing member 32 of the energy absorbing assembly 3. When the battery cell 21 is thermally runaway, the ejected material after the explosion-proof valve 211 ruptures can be absorbed by the energy absorbing member 32, thereby reducing the impact and avoiding damage to other components of the battery pack caused by the impact energy after the explosion-proof valve 211 ruptures.

[0043] The battery pack can prevent the ejected material after the explosion-proof valve 211 ruptures from impacting other structures of the battery pack, prevent the spread of thermal runaway, and reduce safety risks.

[0044] In this embodiment, the energy absorbing assembly 3 further includes a support member 31, a fireproof groove 33 is arranged on the side of the support member 31 facing the explosion-proof valve 211, the fireproof groove 33 extends along the first direction and penetrates the support member 31, the energy absorbing member 32 is arranged in the fireproof groove 33, the support member 31 is fixedly arranged in the accommodating cavity 11, and the energy absorbing member 32 is arranged in the fireproof groove 33 and spaced from the battery unit 2. The support member 31 can ensure the strength of the energy absorbing assembly 3, and prevent the energy absorbing assembly 3 from deforming when impacted by the ejected object and affecting the absorption of the ejected object; at the same time, the energy absorbing member 32 extends along the first direction, and the high-pressure gas released from the explosion-proof valve 211 is discharged along the first direction.

[0045] The jet released from the explosion-proof valve 211 is divergent. In one embodiment, in order to make most or all of the jet spray into the energy absorbing member 32, the size of the fireproof groove 33 in the second direction is greater than or equal to the size of the explosion-proof valve 211 in the second direction; wherein the second direction is perpendicular to the first direction, and the second direction is consistent with the height direction of the support member 31, and the first direction is consistent with the length direction of the support member 31.

[0046] In order to increase the power of the battery pack, it is necessary to set as many battery cells 21 as possible. To achieve this purpose, multiple battery cells 21 are stacked along the thickness direction of the battery pack (i.e., along the second direction) and along the length direction of the battery pack (i.e., the first direction) to form multiple battery assemblies. Multiple energy absorbing members 32 are arranged in the support member 31 along the thickness direction of the battery pack. The multiple energy absorbing members 32 are opposite to the multiple battery assemblies one by one. Among them, the multiple explosion-proof valves 211 of each battery assembly are on the same side, such as Figure 1 and Figure 2 As shown, the battery unit 2 includes two stacked battery assemblies, two energy-absorbing parts 32 are arranged in the fireproof groove 33 along the thickness direction of the battery pack, and the energy-absorbing parts 32 extend along the arrangement direction of the battery cells 21 of the battery assembly to ensure that the explosion-proof valve 211 of each battery cell 21 can face the energy-absorbing part 32.

[0047] like Figure 5 As shown, the battery cell 21 includes an explosion-proof valve 211, an electrode column 212 (the electrode column 212 includes a positive electrode column and a negative electrode column), a battery cell assembly 213, a battery housing 214 (the battery housing 214 has a maximum face 215 arranged opposite to each other), an electrode column connector 216 and a cover plate 217. The battery housing 214 may have a hexahedral shape or other shapes, that is, the battery cell 21 may be a square shell battery or a blade battery, etc. The battery housing 214 has an internal space for accommodating the battery cell assembly 213, and the battery housing 214 has an opening. The battery cell assembly 213 is accommodated in the battery housing 214, and the cover plate 217 covers the opening of the battery housing 214, and is used to enclose the battery cell assembly 213 in the battery housing 214, and the battery cell assembly 213 and the electrode column 212 are electrically connected through the electrode column connector 216. In this embodiment, there are two electrode post connectors 216, namely, a positive electrode post connector and a negative electrode post connector, which are electrically connected to the positive electrode post and the negative electrode post respectively. The battery housing 214 can be made of materials such as aluminum, aluminum alloy or plastic.

[0048] The battery cell assembly 213 is contained in the battery housing 214, and the battery cell assembly 213 includes a positive electrode sheet, a negative electrode sheet, and a diaphragm and / or a solid electrolyte membrane disposed between the positive electrode sheet and the negative electrode sheet. Among them, the diaphragm is an insulator between the positive electrode sheet and the negative electrode sheet. The battery cell assembly 213 can be a winding structure or a laminated structure; regardless of the structure adopted, the largest surface of the battery cell assembly 213 is arranged parallel to the largest surface of the battery housing 214. That is, when the battery cell assembly 213 is a winding structure, the battery cell assembly 213 is flat, and the outer surface of the battery cell assembly 213 includes two flat surfaces, and the two flat surfaces face each other along the thickness direction of the battery cell 21 (i.e., the second direction). The battery cell assembly 213 is roughly a hexahedral structure, and the flat surface is roughly parallel to the winding axis and is the outer surface with the largest area. The flat surface can be a relatively flat surface, and it is not required to be a pure plane. When the battery cell is a laminated structure, the positive electrode sheet, the separator and the negative electrode sheet are stacked along the height direction of the battery cell 21 .

[0049] Among them, the battery unit 2 also includes a fixing belt 22. Multiple battery cells 21 will eventually be stacked into a rectangular shape. The fixing belt 22 can bundle and fix multiple battery cells 21, improve the structural stability of the battery unit 2, and provide a suitable pre-tightening force for the battery unit 2, thereby extending the service life of the battery cell 21.

[0050] like Figure 1 and Figure 2 As shown, the battery pack includes a plurality of energy absorbing assemblies 3, and energy absorbing parts 32 are disposed on opposite sides of the energy absorbing assemblies 3. Battery cells 2 with explosion-proof valves 211 facing the energy absorbing assemblies 3 are disposed on opposite sides of each energy absorbing assembly 3. This structure can ensure that the explosion-proof valves 211 of all battery cells 21 are matched with energy absorbing assemblies 3, so that when any battery cell 21 has thermal runaway, the energy absorbing parts 32 can absorb the ejected matter to prevent the spread of thermal runaway.

[0051] In order to enable the energy absorbing member 32 to absorb the ejected material when the explosion-proof valve 211 ruptures, the energy absorbing member 32 adopts a sponge-like structure, a bird's nest-like structure, a fluffy structure or a layered porous structure; so that the ejected material can enter the energy absorbing member 32 and release the gas pressure of the ejected material along the first direction of the energy absorbing member 32.

[0052] Specifically, the sponge-like structure can be made of metal sponge, which is a loose, porous, sponge-like metal (or alloy) produced by a smelting process. Sponge metal has a large specific surface area because it is porous. Compared with dense metals, it has a large adsorption capacity, good air permeability, high chemical activity, easy oxidation, and low conductivity; the high-pressure gas accompanying the ejecta can be released along the first direction of the metal sponge, preventing the accumulation of air pressure inside the energy-absorbing member 32. In an alternative technical solution, the energy-absorbing member 32 can also be a bird's nest or fluffy structure composed of refractory fibers (glass fibers or ceramic limiters). The bird's nest or fluffy structure includes multiple channels. The bird's nest or fluffy structure can absorb the impact energy released by the explosion-proof valve 211, and the ejected combustion particles are sprayed into the channel and deposited, preventing the risk of the combustion particles scattering and affecting other battery cells 21. In another alternative technical solution, the energy-absorbing member 32 can also be a layered porous structure woven with a metal mesh having a multi-layer porous structure.

[0053] It is understandable that if the energy absorbing member 32 wants to absorb the ejected material passing through the explosion-proof valve 211, there must be space to accommodate the ejected material. In this embodiment, the energy absorbing member 32 includes a plurality of pores, and the plurality of pores are all open on the side of the energy absorbing member 32 facing the battery cell 21. In other words, the energy absorbing member 32 is a loose and porous structure, and the ejected material can enter the pores and deposit, thereby preventing the risk of the high-temperature ejected material scattering and affecting other battery cells 21. At the same time, the pores will be closed under the subsequent impact to prevent the combustion of the ejected material.

[0054] Specifically, the energy absorbing member 32 is composed of refractory fibers and / or refractory foams, and the supporting member 31 is integrally formed of a refractory material, such as mica or a metal profile coated with a refractory coating.

[0055] like Figure 2 and Figure 3 As shown, the support member 31 includes a vertical baffle portion 311 and two horizontal baffle portions 312 arranged at both ends of the vertical baffle portion 311, and the vertical baffle portion 311 and the two horizontal baffle portions 312 form an "I"-shaped structure.

[0056] like Figure 1 and Figure 4 As shown, the bottom plate of the box body 1 is provided with a support beam 12, and the energy absorption assembly 3 is fixedly arranged on the support beam 12. The support beam 12 can improve the overall strength of the box body 1 to better protect the battery cells 21 in the box body 1, and the energy absorption assembly 3 is arranged on the support beam 12, which can avoid occupying the space where the battery cells 21 are arranged, thereby improving the space utilization. At the same time, the side wall of the battery cell 21 abuts against the side wall of the support beam 12.

[0057] Specifically, the support beam 12 is provided with a positioning column 13, and the energy absorbing assembly 3 is provided with a positioning hole, into which the positioning column 13 is inserted. The plug-in fit between the positioning column 13 and the positioning hole can improve the stability of the connection between the energy absorbing assembly 3 and the support beam 12. In this embodiment, the positioning hole is provided in the support member 31.

[0058] like Figure 1 and Figure 4 As shown, the battery pack also includes an upper box cover 4, which is arranged on the box body 1 to close the accommodating cavity 11. The upper box cover 4 is provided with a fixing groove, and the energy absorbing assembly 3 is partially arranged in the fixing groove. The upper box cover 4 can play the role of closing the accommodating cavity 11 to protect the internal structure of the box body 1, and the fixing groove of the upper box cover 4 can cooperate with the positioning column 13 to limit the energy absorbing assembly 3 to ensure the stability of the position of the energy absorbing assembly 3 in the box body 1. In this embodiment, the upper box cover 4 is fixedly provided with a U-shaped member 41, and the U-shaped member 41 forms the above-mentioned fixing groove. One end of the support member 31 of the energy absorbing assembly 3 is inserted into the U-shaped member 41 to improve stability. At the same time, the side wall portion of the battery cell 21 abuts against the outer side wall of the U-shaped member 41.

[0059] It can be understood that the side wall of the battery unit 2 and the side wall of the "I"-shaped energy absorbing assembly 3 or the support beam 12 and the U-shaped member 41 form a relatively sealed structure from top to bottom, and the spray released from the explosion-proof valve 211 will not be discharged upward or downward, that is, the spray is released to the side of the battery pack and will not affect the passengers above the battery pack.

[0060] like Figure 1 to Figure 6 As shown, the vehicle includes the battery pack 5, and the battery pack 5 is placed on the chassis of the vehicle. The bottom surface of the box body 1 of the battery pack 5 is parallel to the bottom surface of the vehicle chassis 6, that is, the plane where the explosion-proof valve 211 of the battery cell 21 is located is perpendicular to the plane where the vehicle chassis 6 is located. After the explosion-proof valve 211 ruptures, the ejecta released from the explosion-proof valve 211 are released to the side of the vehicle and will not affect the passengers inside the vehicle.

[0061] The above contents are only preferred embodiments of the present invention. For ordinary technicians in this field, according to the concept of the present invention, there will be changes in the specific implementation methods and application scopes. The contents of this specification should not be understood as limiting the present invention.

Claims

1. A battery pack, characterized in that: include: A plurality of battery units (2), wherein the battery units (2) include a plurality of battery cells (21), and the battery cells (21) include explosion-proof valves (211); An energy absorbing component (3), wherein an energy absorbing member (32) is provided on a side of the energy absorbing component (3) facing the battery unit (2), and the energy absorbing member (32) is configured to absorb ejected matter when the explosion-proof valve (211) ruptures.

2. The battery pack according to claim 1, characterized in that: The energy absorbing component (3) further comprises a support member (31), a fireproof groove (33) being arranged on a side of the support member (31) facing the explosion-proof valve (211), the fireproof groove (33) extending along a first direction and penetrating the support member (31), and the energy absorbing member (32) being arranged in the fireproof groove (33).

3. The battery pack according to claim 2, characterized in that: The size of the fireproof groove (33) in the second direction is greater than or equal to the size of the explosion-proof valve (211) in the second direction; The second direction is perpendicular to the first direction, and the second direction is consistent with the height direction of the support member (31), and the first direction is consistent with the length direction of the support member (31).

4. The battery pack according to claim 1, characterized in that: The battery unit (2) comprises a plurality of battery cells (21) stacked in a first direction and / or a second direction; the number of the energy absorbing members (32) corresponds to the number of the battery cells (21) stacked in the second direction of the battery unit (2); the energy absorbing member (32) extends in the first direction; The second direction is perpendicular to the first direction, and the second direction is consistent with the thickness direction of the battery cell.

5. The battery pack according to claim 1, characterized in that: Two adjacent battery cells (2) form a battery module, the energy absorbing component (3) is arranged between the two battery cells of the battery module, and the explosion-proof valves (211) of the battery cells (21) in the two battery cells (2) both face the energy absorbing component (32).

6. The battery pack according to claim 1, characterized in that: The energy absorbing member (32) comprises a sponge-like structure, a bird's nest-like structure, a fluffy structure or a layered porous structure.

7. The battery pack according to claim 2, characterized in that: The support member (31) comprises a vertical baffle portion (311) and two horizontal baffle portions (312) arranged at two ends of the vertical baffle portion (311), and the vertical baffle portion (311) and the two horizontal baffle portions (312) form an "I"-shaped structure.

8. The battery pack according to claim 1, characterized in that: The battery pack further comprises a box body (1), the box body (1) having a receiving cavity (11), the battery unit (2) and the energy absorption assembly (3) being received in the receiving cavity (11), and the surface where the explosion-proof valve (211) is located is perpendicular to the bottom surface of the box body (1).

9. The battery pack according to claim 8, characterized in that: The bottom plate of the box body (1) is provided with a support beam (12), and the energy absorption component (3) is fixedly arranged on the support beam (12); the support beam (12) is provided with a positioning column (13), and the energy absorption component (3) is provided with a positioning hole, and the positioning column (13) is inserted into the positioning hole; Alternatively, the battery pack further comprises an upper box cover (4), wherein the upper box cover (4) is arranged on the box body (1) to close the accommodating cavity (11), and the upper box cover (4) is provided with a fixing groove, and the energy absorption component (3) is partially arranged in the fixing groove.

10. A vehicle, characterized in that: The vehicle comprises a vehicle body and a battery pack according to any one of claims 1 to 9, wherein the battery pack is arranged in the vehicle body, and the surface where the explosion-proof valve (211) is located is perpendicular to the surface where the vehicle chassis is located.

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