Battery cell, battery pack, and energy storage device

Abstract

The application provides an electric core, a battery pack and an energy storage device. The electric core comprises a shell, an end cover, a winding core and an explosion-proof valve. The end cover is sealed at an opening of the shell. The winding core is arranged in the shell. The explosion-proof valve is integrated on the end cover. The electric core further comprises a current collector. The current collector is electrically connected to each tab of the winding core. The end cover is formed with a channel. The channel communicates the explosion-proof valve and the winding core through an internal space of the shell. The current collector is disc-shaped and is configured to separate the channel. A plurality of through holes are formed on the current collector. The through holes are configured to allow gas to pass through and block solid particles. The electric core, the battery pack and the energy storage device provided by the application can filter the ejected solid particles while maintaining the volume of the electric core.

Description

Technical Field

[0001] This application relates to the field of mobile energy storage technology, and more particularly to a battery cell, battery pack and energy storage device. Background Technology

[0002] When a battery cell experiences thermal runaway, due to the high gas production rate, solid particles are usually ejected from the explosion-proof valve along with the gas flow. During the ejection process, these solid particles can easily generate sparks when they collide with metal materials, igniting flammable gases and causing a fire and explosion.

[0003] In related technologies, the conventional approach is to install a flame arrester outside the explosion-proof valve of the battery cell to suppress the flame emitted from the explosion-proof valve. However, adding a flame arrester will increase the size of the battery cell and significantly increase the manufacturing cost. Utility Model Content

[0004] In view of this, this application provides a battery cell, a battery pack, and an energy storage device that can filter out ejected solid particles while maintaining the volume of the battery cell.

[0005] One embodiment of this application provides a battery cell. The battery cell includes a housing, an end cap, a core, and an explosion-proof valve. The end cap is sealed at an opening in the housing. The core is disposed within the housing. The explosion-proof valve is integrated into the end cap. The battery cell also includes a current collector. The current collector is electrically connected to each tab of the core. The end cap forms a channel. The channel connects the explosion-proof valve and the core through the internal space of the housing. The current collector is disc-shaped and configured to separate the channel and the core. The current collector has multiple through holes. The through holes are configured to allow gas to pass through and block solid particles.

[0006] By incorporating through-holes in the current collector, solid particles can be filtered out before they exit the explosion-proof valve, effectively reducing the risks associated with particulate matter ejection. Furthermore, since the current collector functions as a filter structure, no additional filter is needed, thus minimizing the impact on the overall cell size and helping to maintain the cell's compactness.

[0007] In some embodiments of this application, the current collector covers the side of the winding core facing the end cap.

[0008] When the battery cell experiences thermal runaway, the solid particles ejected from the core towards the end cover can be directly filtered by the current collector, which helps prevent the solid particles from spreading to other parts of the casing.

[0009] In some embodiments of this application, the current collector includes a current collector plate and a baffle. The current collector plate is electrically connected to each tab of the winding core. Multiple current collector plates are provided. Each current collector plate has a through hole. The multiple current collector plates are arranged at intervals from the winding core towards the explosion-proof valve. The baffle is disposed between two adjacent current collector plates. The baffle is configured to prevent solid particles from entering or exiting the space between two adjacent current collector plates.

[0010] The collector plate is used to electrically connect the various tabs of the battery cell. Its relatively large structure facilitates the installation of through holes to allow gas to pass through and filter solid particles. Multiple collector plates can form a multi-layer structure to facilitate multiple filtrations of solid particles, thereby improving the filtration efficiency.

[0011] In some embodiments of this application, when viewed along the direction of the arrangement of multiple collector plates, the axis of each through hole in one collector plate and the axis of each through hole in adjacent collector plates are set separately.

[0012] The through holes of adjacent collector plates can be staggered, making the path of solid particles through the multi-layer collector plates tortuous. This helps to prevent solid particles from passing through the through holes of one collector plate and then passing through the through holes of the next collector plate, thus improving the filtration effect.

[0013] In some embodiments of this application, in two adjacent collector plates, the diameter of the through hole of the collector plate closer to the core is larger than the diameter of the through hole of the collector plate farther from the core.

[0014] When filtering solid particles using multi-layer manifolds, the manifolds further away from the core filter out smaller solid particles. This helps prevent solid particles of different sizes from clogging the same layer of manifolds, allowing gas to pass through the through holes.

[0015] In some embodiments of this application, the current collector includes a current collector plate and a first rib. The current collector plate is electrically connected to each tab of the winding core. The current collector plate has through holes. The first rib is located on the side of the current collector plate facing the winding core. The first rib is supported on the winding core so that the current collector plate and the winding core are spaced apart.

[0016] The current collector is used to electrically connect the various tabs of the battery cell. Its relatively large structure facilitates the installation of through holes to allow gas to pass through and filter solid particles. The first rib can support the current collector relative to the core, thereby reducing the area of ​​the current collector in contact with the core. This helps to prevent the part of the current collector without through holes from blocking the core and affecting exhaust.

[0017] In some embodiments of this application, at least a portion of the first rib is arranged around the axis of the core.

[0018] The first rib can fix the core, which helps to prevent the core from unwinding. This allows the collector to not only be electrically connected to the core and filter solid particles, but also fix the core structure, which helps to reduce the need for other core fixing structures and improve the space utilization rate inside the housing.

[0019] In some embodiments of this application, the current collector abuts against the housing and / or end cap, and the space and channel where the core is located are connected only through the through hole of the current collector.

[0020] The manifold separates the channel and the space where the core is located, and can filter solid particles released from the core except for the part facing the end cap, thus improving the filtration effect.

[0021] In some embodiments of this application, the current collector includes a current collector plate and a second rib. The current collector plate is electrically connected to each tab of the winding core. The current collector plate has through holes. The second rib is located on the side of the current collector plate opposite to the winding core. At least a portion of the second rib is supported by an end cap, such that the current collector plate and the end cap are spaced apart.

[0022] The collector plate is used to electrically connect the various tabs of the battery cell. Its large structure facilitates the installation of through holes to allow gas to pass through and filter solid particles. The second rib supports the collector plate relative to the end cap, providing sufficient space between the collector plate and the end cap to accumulate gas and generate enough pressure to open the explosion-proof valve for venting.

[0023] One embodiment of this application provides a battery pack. The battery pack includes a battery casing. The battery pack also includes battery cells as described in any of the above embodiments. The battery cells are assembled within the battery casing.

[0024] When the battery pack cells experience thermal runaway, the ejected solid particles can be reduced, lowering the possibility of fire and improving the safety of the battery pack. Furthermore, the cell volume change is relatively small, which helps maintain the same energy storage capacity for battery packs of the same volume.

[0025] One embodiment of this application provides an energy storage device. The energy storage device includes an energy storage housing. The energy storage device also includes a battery pack as described in any of the above embodiments, the battery pack being housed within the energy storage housing.

[0026] When the battery cells of an energy storage device experience thermal runaway, the ejected solid particles can be reduced, lowering the possibility of fire and improving the safety of the energy storage device. Furthermore, the change in cell volume is relatively small, which is beneficial for energy storage devices of the same volume to maintain the same energy storage capacity. Attached Figure Description

[0027] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation on the scope.

[0028] Figure 1 This is a schematic diagram of the structure of an energy storage device provided in an embodiment of this application; Figure 2 for Figure 1 Explosion diagram of a medium-sized energy storage device; Figure 3 for Figure 2 A schematic diagram of the structure of the battery cell; Figure 4 for Figure 3Cross-sectional view of the battery cell; Figure 5 for Figure 4 Schematic diagram of the flow element structure; Figure 6 for Figure 4 A schematic diagram of another form of the central flow element; Figure 7 for Figure 4 A schematic diagram of another form of the central flow element.

[0029] Explanation of main component symbols 100 - Battery cell; 200 - Battery pack; 300 - Energy storage device; 10-Shell; 11-Opening; 20-End cap; 21-Channel; 30-Core; 40-Explosion-proof valve; 50-Current collector; 51-Current collector plate; 52-Enclosure; 53-First rib; 54-Second rib; 511 - Through hole; 201 - Battery casing; 301 - Energy storage casing; 302 - Power conversion module. Detailed Implementation

[0030] The technical solutions of the embodiments of this application will be described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments.

[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0032] As used herein, the term "and / or" includes any and all combinations of one or more of the related listed items.

[0033] Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be interpreted as indicating or implying relative importance.

[0034] When a battery cell experiences thermal runaway, due to the high gas production rate, solid particles are usually ejected from the explosion-proof valve along with the gas flow. During the ejection process, these solid particles can easily generate sparks when they collide with metal materials, igniting flammable gases and causing a fire and explosion.

[0035] In related technologies, the conventional approach is to install a flame arrester outside the explosion-proof valve of the battery cell to suppress the flame emitted from the explosion-proof valve. However, adding a flame arrester will increase the size of the battery cell and significantly increase the manufacturing cost.

[0036] Embodiments of this application provide a battery cell. The battery cell includes a housing, an end cap, a core, and an explosion-proof valve. The end cap is sealed at an opening in the housing. The core is disposed within the housing. The explosion-proof valve is integrated into the end cap. The battery cell also includes a current collector. The current collector is electrically connected to each tab of the core. The end cap forms a channel. The channel connects the explosion-proof valve and the core through the internal space of the housing. The current collector is disc-shaped and configured to separate the channel and the core. The current collector has multiple through holes. The through holes are configured to allow gas to pass through and block solid particles.

[0037] By incorporating through-holes in the current collector, solid particles can be filtered out before they exit the explosion-proof valve, effectively reducing the risks associated with particulate matter ejection. Furthermore, since the current collector functions as a filter structure, no additional filter is needed, thus minimizing the impact on the overall cell size and helping to maintain the cell's compactness.

[0038] The following detailed description of some embodiments of this application is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0039] See Figure 1 and Figure 2 One embodiment of this application provides a battery cell 100, a battery pack 200, and an energy storage device 300. The energy storage device 300 has the functions of storing and discharging electricity for use as backup power in homes, production facilities, and for outdoor work and recreation. The battery pack 200 is the structure for storing electrical energy in the energy storage device 300. The battery cell 100 is the structure for storing electrical energy in the battery pack 200.

[0040] In some embodiments, the energy storage device 300 includes an energy storage housing 301 and a battery pack 200. The energy storage housing 301 is used to house the battery pack 200, which is assembled within the energy storage housing 301. The battery pack 200 is used in the energy storage device 300, but the battery pack 200 can also be manufactured, transported, and used independently of the energy storage device 300.

[0041] In some embodiments, the energy storage device 300 further includes a power conversion module 302. The power conversion module 302 is electrically connected to the battery pack 200 and is used to control the AC / DC conversion of the output current of the battery pack 200. The energy storage device 300 equipped with the power conversion module 302 can be a small portable power bank, a residential energy storage power supply, an industrial or commercial energy storage power supply, or a containerized energy storage power supply, etc.

[0042] In other embodiments, the power conversion module 302 may be omitted. An energy storage device 300 without a power conversion module 302 can be used independently. An energy storage device 300 without a power conversion module 302 typically only outputs DC power. When used independently, an energy storage device 300 without a power conversion module 302 can be used in conjunction with an energy storage device 300 with a power conversion module 302 as a power system providing additional battery capacity.

[0043] In some embodiments, the battery pack 200 includes a battery casing 201 and a battery cell 100. The battery casing 201 is used to house the battery cell 100, and the battery cell 100 is assembled inside the battery casing 201. The battery cell 100 is used in the battery pack 200, and the battery cell 100 can also be manufactured, transported, and used independently of the battery pack 200.

[0044] It is understood that in some embodiments, the battery casing 201 and the energy storage casing 301 are integrally formed structures, which can improve the space utilization within the energy storage device 300 and enhance the stability of the battery pack 200 within the energy storage casing 301.

[0045] See Figure 3 and Figure 4 In some embodiments, the battery cell 100 includes a housing 10, an end cap 20, a core 30, and an explosion-proof valve 40. The end cap 20 is sealed at the opening 11 of the housing 10. The core 30 is disposed inside the housing 10. The explosion-proof valve 40 is integrated onto the end cap 20. The core 30 passes through the opening 11 of the housing 10 to be assembled into the housing 10, and the end cap 20 is sealed at the opening 11 of the housing 10 to encapsulate the core 30 within the housing 10, placing the core 30 in a sealed space. When the battery cell 100 experiences thermal runaway, the core 30 will generate gas, which accumulates inside the housing 10. The explosion-proof valve 40 automatically opens when the gas pressure inside the housing 10 reaches a set value to release the gas.

[0046] See Figures 2 to 4 In some embodiments, the cell 100 further includes a current collector 50. The current collector 50 is electrically connected to the tabs (not shown) of the core 30. The end cap 20 forms a channel 21. The channel 21 communicates with the explosion-proof valve 40 and the core 30 through the internal space of the housing 10. The current collector 50 is disc-shaped and configured to separate the channel 21 and the core 30. The current collector 50 has a plurality of through holes 511. The through holes 511 are configured to allow gas to pass through and block solid particles.

[0047] When cell 100 experiences thermal runaway, the winding core 30 generates solid particles along with gas. By incorporating a through-hole 511 into the current collector 50, solid particles can be filtered out before they exit the explosion-proof valve 40, effectively reducing the risk of solid particle ejection and improving the safety of the battery pack 200 and energy storage device 300. Simultaneously, the through-hole 511 in the current collector 50 facilitates the flow of gas generated by the winding core 30 through the current collector 50 to the channel 21, enabling the explosion-proof valve 40 to release gas.

[0048] Furthermore, the current collector 50 is provided with a through hole 511 to serve as a filter structure, eliminating the need for a separate filter structure. Therefore, it has a smaller impact on the overall volume of the cell 100, which helps maintain the volume of the cell 100. This, in turn, helps maintain the same energy storage capacity for battery packs 200 of the same volume, and further helps maintain the same energy storage capacity for energy storage devices 300 of the same volume.

[0049] See Figures 5 to 7 In some embodiments, the multiple through holes 511 provided on the current collector 50 are arranged in an array (e.g., Figure 5 (as shown) or radial distribution (e.g.) Figure 6 As shown), it has a good blocking effect on solid particles, improving the filtration effect of the collector 50, and the collector 50 has good structural strength so that the part of the collector 50 without through holes 511 can resist the impact of gas. In some embodiments, the through holes 511 provided in the collector 50 are presented as strip holes (e.g., Figure 7 As shown, increasing the cross-sectional size of a single through hole 511 facilitates gas passage. Even if solid particles are blocked at the through hole 511, the through hole 511 can still have a portion that is not blocked by solid particles to allow gas to pass through.

[0050] See Figure 4 In some embodiments, the current collector 50 covers the side of the core 30 facing the end cap 20. In the event of thermal runaway of the cell 100, solid particles ejected from the side of the core 30 facing the end cap 20 can be directly filtered by the current collector 50, which helps to prevent solid particles from spreading to other locations inside the housing 10.

[0051] In some embodiments, the end cap 20 equipped with the explosion-proof valve 40 is only provided at one end of the housing 10, and at least one of the opposite ends of the core 30 is provided with a collector 50 having a through hole 511 on the side facing the explosion-proof valve 40. When the battery cell 100 experiences thermal runaway, the side of the core 30 facing the explosion-proof valve 40 can directly release air through the explosion-proof valve 40, easily carrying solid particles out of the explosion-proof valve 40. The collector 50 with the through hole 511 on the side of the core 30 facing the explosion-proof valve 40 can effectively block solid particles. It is understood that in some embodiments, the side of the core 30 facing away from the explosion-proof valve 40 is also provided with a collector 50 with a through hole 511 to block solid particles ejected from the side of the core 30 facing away from the explosion-proof valve 40, thereby improving the filtration effect on solid particles ejected from the core 30. In other embodiments, end caps 20 equipped with explosion-proof valves 40 are located at both ends of housing 10, and both ends of core 30 are provided with flow collectors 50 having through holes 511, which helps to ensure that solid particles are not carried out of explosion-proof valves 40 when the two ends of core 30 are depressurized and sprayed through explosion-proof valves 40.

[0052] In other embodiments, the current collector 50 may not completely cover the side of the core 30 facing the end cap 20, the current collector 50 may only cover the area corresponding to the channel 21, and the current collector 50 may fit against the end cap 20 to cover the end of the channel 21 facing the core 30.

[0053] In some embodiments, the current collector 50 includes a current collector disk 51. The current collector disk 51 is electrically connected to each tab of the core 30. The current collector disk 51 is provided with a through hole 511. The current collector disk 51 is used to electrically connect to each tab of the battery cell 100. Its structure is relatively large, which facilitates the provision of the through hole 511 to allow gas to pass through and filter solid particles.

[0054] In some embodiments, multiple collector plates 51 are provided. Each collector plate 51 is provided with a through hole 511. The multiple collector plates 51 are arranged at intervals from the core 30 toward the explosion-proof valve 40. The collector 50 also includes a barrier 52. The barrier 52 is disposed between two adjacent collector plates 51. The barrier 52 is configured to prevent solid particles from entering or exiting the space between two adjacent collector plates 51.

[0055] Multiple collector discs 51 can form a multi-layer structure to facilitate multiple filtrations of solid particles and improve the filtration effect of solid particles.

[0056] Understandably, in some embodiments, the enclosure 52 is a ring structure to facilitate the blocking of solid particles.

[0057] Understandably, in some embodiments, the enclosure 52 and the collector plate 51 are integrally formed, which facilitates the assembly of the collector 50 to the core 30.

[0058] In some embodiments, when viewed along the arrangement of the multiple collector plates 51, the axis of each through hole 511 in one collector plate 51 and the axis of each through hole 511 in adjacent collector plates 51 are separated. The through holes 511 of adjacent collector plates 51 can be staggered, making the path of solid particles through the multiple collector plates 51 tortuous. This helps to prevent solid particles from passing through the through holes 511 of one collector plate 51 and then smoothly passing through the through holes 511 of the next collector plate 51, thus improving the filtration effect.

[0059] The separation of the axes of two through holes 511 located on different collector plates 51 is understood as follows: when viewed along the distribution direction of multiple collector plates 51, the two through holes 511 partially overlap, partially do not overlap, or the two through holes 511 are connected, or the two through holes 511 are separated.

[0060] In some embodiments, in two adjacent collector disks 51, the diameter of the through hole 511 of the collector disk 51 closer to the core 30 is larger than the diameter of the through hole 511 of the collector disk 51 farther from the core 30.

[0061] When filtering solid particles in the multi-layer manifold 51, the manifold 51 further away from the core 30 filters smaller solid particles, which helps to prevent solid particles of different sizes from clogging the same layer of manifold 51, so that gas can pass through the through hole 511.

[0062] In some embodiments, the collector 50 further includes a first rib 53. The first rib 53 is disposed on the side of the collector 51 facing the core 30. The first rib 53 is supported on the core 30 so that the collector 51 and the core 30 are spaced apart. The first rib 53 can support the collector 51 relative to the core 30, thereby reducing the area of ​​the collector 50 in contact with the core 30, which helps to prevent the portion of the collector 51 without through holes 511 from obstructing the core 30 and affecting exhaust.

[0063] When multiple collector plates 51 are provided, the first rib 53 is provided on the collector plate 51 closest to the core 30.

[0064] Understandably, in some embodiments, the first rib 53 and the collector plate 51 are integrally formed, which facilitates the assembly of the collector 50 to the core 30.

[0065] In some embodiments, at least a portion of the first rib 53 is arranged around the axis of the core 30 and is disposed around the periphery of the core 30. The first rib 53 can fix the core 30, which helps to prevent the core 30 from unwinding. This allows the collector 50 to not only be electrically connected to the core 30 and filter solid particles, but also to fix the core 30 structure. This helps to reduce the need for other structures that fix the core 30 and improves the space utilization within the housing 10.

[0066] Understandably, in some embodiments, the first rib 53 is an annular structure and is configured to block solid particles from entering or exiting the space between the collector plate 51 and the core 30.

[0067] In some embodiments, the collector 50 abuts against the housing 10 and / or the end cap 20, and connects the space where the core 30 is located and the channel 21 only through the through hole 511 of the collector 50. The collector 50 separates the channel 21 and the space where the core 30 is located, and can filter solid particles released from the core 30 except for the part facing the end cap 20, thereby improving the filtration effect.

[0068] In some embodiments, the collector 50 further includes a second rib 54. The second rib 54 is disposed on the side of the collector 51 opposite to the core 30. At least a portion of the second rib 54 is supported by the end cap 20, such that the collector 51 and the end cap 20 are spaced apart. The second rib 54 can support the collector 51 relative to the end cap 20, so that there is sufficient space between the collector 51 and the end cap 20 to accumulate gas, providing sufficient gas pressure to open the explosion-proof valve 40 for venting.

[0069] When multiple collector plates 51 are provided, the second rib 54 is provided on the collector plate 51 closest to the end cover 20.

[0070] In other embodiments, the collector plate 51 may be fitted to the end cap 20, or the collector plate 51 may have at least a portion of its structure located within the channel 21 to prevent solid particles from entering the channel 21.

[0071] Understandably, in some embodiments, the second rib 54 and the collector plate 51 are integrally formed, which facilitates the assembly of the collector 50 to the core 30.

[0072] Furthermore, those skilled in the art should recognize that the above embodiments are merely illustrative of this application and are not intended to limit this application. Any appropriate changes and variations made to the above embodiments within the essential spirit and scope of this application fall within the scope of this application's disclosure.

Claims

1. A battery cell, comprising a housing, an end cap, a winding core, and an explosion-proof valve, wherein the end cap is sealed at an opening of the housing, the winding core is disposed within the housing, and the explosion-proof valve is integrated onto the end cap, characterized in that: The battery cell also includes a current collector electrically connected to each tab of the core. The end cap forms a channel that connects the explosion-proof valve and the core through the internal space of the housing. The current collector is disc-shaped and configured to separate the channel and the core. The current collector has multiple through holes configured to allow gas to pass through and block solid particles.

2. The battery cell according to claim 1, characterized in that, The current collector covers the side of the winding core facing the end cap.

3. The battery cell according to claim 2, characterized in that, The current collecting device includes a current collecting plate and a barrier. The current collecting plate is electrically connected to each tab of the winding core. There are multiple current collecting plates, each of which has a through hole. The multiple current collecting plates are arranged at intervals from the winding core to the explosion-proof valve. The barrier is located between two adjacent current collecting plates and is configured to prevent solid particles from entering or exiting the space between two adjacent current collecting plates.

4. The battery cell according to claim 3, characterized in that, Viewed along the direction of the arrangement of the plurality of collector plates, the axis of each through hole in one collector plate and the axis of each through hole in adjacent collector plates are all separated; and / or, In two adjacent collector plates, the diameter of the through hole in the collector plate closer to the core is larger than the diameter of the through hole in the collector plate farther from the core.

5. The battery cell according to any one of claims 1 to 4, characterized in that, The current collector includes a current collector plate and a first rib. The current collector plate is electrically connected to each of the tabs of the winding core. The current collector plate is provided with the through hole. The first rib is provided on the side of the current collector plate facing the winding core and is supported by the winding core so that the current collector plate and the winding core are spaced apart.

6. The battery cell according to claim 5, characterized in that, At least a portion of the first rib is arranged around the axis of the core and is circumferentially disposed on the core.

7. The battery cell according to any one of claims 1 to 4, characterized in that, The current collector abuts against the housing and / or the end cap, and makes the space where the core is located and the channel connected only through the through hole of the current collector.

8. The battery cell according to claim 7, characterized in that, The current collector includes a current collector plate and a second rib. The current collector plate is electrically connected to each of the tabs of the winding core. The current collector plate is provided with the through hole. The second rib is provided on the side of the current collector plate away from the winding core. At least part of the second rib is supported by the end cap so that the current collector plate and the end cap are spaced apart.

9. A battery pack, comprising a battery casing, characterized in that, The battery pack further includes a battery cell as described in any one of claims 1 to 8, the battery cell being assembled within the battery casing.

10. An energy storage device, comprising an energy storage housing, characterized in that, The energy storage device further includes the battery pack as described in claim 9, the battery pack being disposed within the energy storage housing.

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