Battery cell and energy storage device

Abstract

The embodiment of the application discloses an electric core and an energy storage device, and relates to the technical field of electric cores, wherein the electric core comprises at least two core packages and heat insulation materials, at least part of the outer surface of at least one of the core packages is covered with the heat insulation materials, the heat insulation materials are used to slow down heat transfer on the core packages, and at least one of the core packages is not connected with the heat insulation materials. The technical scheme provided by the embodiment of the application aims to improve the structural stability and reliability of the electric core.

Description

Technical Field

[0001] The embodiments in this application relate to the field of battery cell technology, and in particular to a battery cell and an energy storage device. Background Technology

[0002] Existing battery cells typically consist of at least two core packages, which can be combined and arranged inside the battery cell by means of winding or stacking to ensure stable charging and discharging operation of the battery cell.

[0003] However, when thermal runaway occurs in some core packages, causing a sudden rise in temperature, the heat can easily spread to other core packages or other adjacent cells, which can easily cause more and more core packages to experience thermal runaway, resulting in a sharp increase in the overall temperature of the cell. This can easily cause the cell to catch fire or even explode, reducing the structural stability and reliability of the cell. Summary of the Invention

[0004] Several embodiments in this application propose a battery cell and an energy storage device, aiming to improve the structural stability and reliability of the battery cell.

[0005] One embodiment of this application proposes a battery cell comprising at least two core packages and a thermal insulation material, wherein at least a portion of the outer surface of at least one of the core packages is covered with the thermal insulation material to mitigate heat transfer on the core package, and at least one of the core packages is not connected to the thermal insulation material.

[0006] In one embodiment, the insulating material is disposed between any two adjacent core packages.

[0007] In one embodiment, the battery cell further includes a housing, the housing having a receiving space, at least two of the core packages being arranged in the receiving space, and at least a portion of the outer surface of the core packages facing the inner wall of the receiving space being covered with the heat-insulating material.

[0008] In one embodiment, the core package includes two opposing first surfaces and two opposing second surfaces, the two first surfaces being connected to the two second surfaces, the area of ​​the first surfaces being larger than the area of ​​the second surfaces, and the insulating material covering at least one of the first surfaces.

[0009] In one embodiment, the core package includes tabs, at least a portion of which is covered with an insulating material.

[0010] In one embodiment, the thermal insulation material includes at least one of polytetrafluoroethylene, polyvinylidene fluoride, and aramid fiber.

[0011] In one embodiment, the core package includes a tab, the tab including a connected main body portion and a fusible portion, wherein the melting point of the structural material of the fusible portion is lower than the melting point of the structural material of the main body portion.

[0012] In one embodiment, the core package includes a first tab and a second tab, the core package has a width direction, the length of the first tab along the width direction is L1, the length of the second tab along the width direction is L2, and L1 < L2.

[0013] In one embodiment, the core package tab has a thickness direction, and the tab includes a first conductive segment and a second conductive segment connected together. The width of the first conductive segment along the thickness direction is D1, and the width of the second conductive segment along the thickness direction is D2, where D1 < D2.

[0014] In one embodiment, the core package includes tabs, and at least two of the core packages have tabs of different sizes.

[0015] This application also proposes an energy storage device comprising the aforementioned battery cell.

[0016] In the various embodiments provided in this application, by covering at least a portion of the outer surface of at least one core package with heat-insulating material and not providing heat-insulating material on at least one core package, a differentiated design of at least two core packages in the battery cell is achieved. The heat-insulating material can be used to isolate heat transfer between core packages, to isolate heat transfer between at least two core packages in the same battery cell, or to isolate heat transfer between core packages of two adjacent battery cells, or to isolate heat transfer between multiple battery cells within the same battery cell and between adjacent battery cells. Thus, when a cell fails due to extreme conditions such as overheating, system circuit short circuits, or overcharging and over-discharging, the cell packs covered with thermal insulation material can heat up faster and trigger thermal runaway more quickly. This helps to create a time difference between the thermal runaway triggering of multiple cell packs within the cell, preventing multiple cell packs from triggering thermal runaway simultaneously, which facilitates cell fault handling. Furthermore, the thermal insulation material reduces heat transfer between cell packs, preventing heat from gradually spreading to other cell packs and triggering thermal runaway in those packs. This helps to reduce the number of cell packs experiencing thermal runaway, effectively slowing down the cell's heating rate, reducing the risk of cell fire or even explosion, and improving the structural stability and reliability of the cell. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments or prior art of this application, the drawings used in the description of the embodiments or prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the structure of an embodiment of the battery cell provided in this application; Figure 2 for Figure 1 An exploded view of the structure of an embodiment of a battery cell; Figure 3 This is a schematic diagram of the structure of the first embodiment of the battery cell package proposed in this application; Figure 4 This is a schematic diagram of the structure of the second embodiment of the battery cell package proposed in this application; Figure 5 This is a schematic diagram of the structure of the third embodiment of the battery cell package proposed in this application; Figure 6 This is a partial structural diagram of the fourth embodiment of the battery cell package proposed in this application; Figure 7 This is a partial structural diagram of the fifth embodiment of the battery cell package proposed in this application. Figure 8 This is a partial structural diagram of the sixth embodiment of the battery cell package proposed in this application. Figure 9 This is a partial structural diagram of the seventh embodiment of the battery cell package proposed in this application. Figure 10 This is an exploded view of the structure of an embodiment of the battery pack proposed in this application; Figure 11 This is a schematic diagram of the structure of an embodiment of the energy storage device proposed in this application; Figure 12 This is a schematic diagram of the structure of an embodiment of the power supply system proposed in this application.

[0019] Explanation of icon numbers: 100. Battery cell; 10. Battery pack; 10a. First surface; 10b. Second surface; 11. Tab; 111. Main body; 113. Fuse; 115. First conductive section; 117. Second conductive section; 11a. First tab; 11b. Second tab; 30. Thermal insulation material; 50. Housing; 200. Battery pack; 300. Energy storage device; 400. Electrical system. Detailed Implementation

[0020] The technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings of several embodiments. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0021] It should be noted that if multiple embodiments of this application involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0022] Furthermore, if multiple embodiments of this application involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text implies three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed in this application.

[0023] In related technologies, a battery cell may include at least two cell packs, which are combined and arranged by means of winding or stacking to enable the battery cell to have a larger capacity and achieve better charging and discharging by utilizing the cooperation of at least two cell packs. A battery pack may include at least one battery cell. When a battery pack has two or more battery cells, the at least two battery cells can be arranged in a certain regular pattern to achieve a more compact overall structural design of the battery pack.

[0024] Under certain extreme abuse conditions, the battery pack is prone to thermal runaway. For example, when the battery pack is subjected to a large amount of heat, the system circuit is short-circuited, or the battery cell is overcharged or over-discharged, the battery pack that triggers thermal runaway will generate a large amount of heat rapidly.

[0025] The cells within a battery cell are tightly packed, and multiple cells in a battery pack are typically also tightly packed. When a cell triggers thermal runaway due to extreme abuse, the large amount of heat generated by the thermally runaway cell can easily and rapidly transfer to adjacent cell packs. In some cases, thermal runaway can even occur within a single cell pack, with heat being transferred to multiple cells through the spacing between them. This can lead to an increasing number of cell packs becoming heated and triggering thermal runaway, causing a rapid rise in temperature within the cell and battery pack, which can easily result in cell fires or even explosions. To address these issues, this application proposes a new type of battery cell.

[0026] Please see Figures 1 to 3 In one embodiment of this application, the battery cell 100 includes at least two core packages 10 and a heat insulation material 30, wherein at least a portion of the outer surface of at least one core package 10 is covered with the heat insulation material 30 to slow down heat transfer on the core package 10, and at least one core package 10 is not connected to the heat insulation material 30.

[0027] In this application, the thermal insulation material 30 can be a material with good thermal insulation performance, such as polytetrafluoroethylene foam, polytetrafluoroethylene fiber composite, polyvinylidene fluoride foam, aramid fiber, aerogel, carbon nanotube film, ceramic fiber, etc. By covering at least a portion of the outer surface of at least one core package 10 with the thermal insulation material 30, the thermal insulation material 30 can be used to isolate the heat transfer at the corresponding outer surface of the core package 10. This can both prevent the heat inside the core package 10 from spreading outward from the outer surface and prevent external heat from spreading to the outer surface of the core package 10 covered with the thermal insulation material 30, thereby playing the role of isolating the heat transfer between the core packages 10.

[0028] When some of the core packages 10 within the battery cell 100 trigger thermal runaway, in some embodiments, if the outer surface of the core package 10 that triggers thermal runaway is covered with a thermal insulation material 30, the thermal insulation material 30 can prevent the heat generated inside the core package 10 from spreading outward. In this case, if the thermal insulation material 30 is placed between adjacent core packages 10 of the same battery cell 100, the heat propagation to adjacent core packages 10 can be reduced; if the thermal insulation material 30 is placed on the outer surface of the core package 10 near the battery cell 100 housing 50, the heat propagation to adjacent battery cells 100 can be reduced, thereby effectively slowing down the heat propagation between multiple core packages 10, preventing more and more core packages 10 from being heated and triggering thermal runaway, and reducing the heating rate of the battery cell 100.

[0029] The use of insulating material 30 to isolate the heat inside the core package 10 that triggers thermal runaway from spreading outwards can also concentrate the heat in the core package 10 that triggers thermal runaway. This makes the core package 10 heat up faster than other core packages 10 that are not connected to insulating material 30, and the time to trigger thermal runaway is shorter. This can effectively increase the time difference between the core packages 10 in the cell 100 that trigger thermal runaway, and make it easier for the tabs 11 on the core package 10 covered with insulating material 30 to be subjected to greater heat and melt. It also helps to disconnect the circuit of the core package 10 that triggers thermal runaway in time, reducing the impact on the electrical performance of the circuit. At the same time, it also helps to further reduce the continuous heating of the thermal runaway core package 10, and further improve the structural stability and reliability of the cell 100.

[0030] In some embodiments, if the core package 10 with the outer surface covered by the thermal insulation material 30 does not trigger thermal runaway, but the core package 10 not connected to the thermal insulation material 30 triggers thermal runaway, the thermal insulation material 30 can isolate the heat generated by the core package 10 that triggers thermal runaway from propagating to the core package 10 covered by the thermal insulation material 30, and can also isolate the heat from propagating to the multiple core packages 10 and the battery cell 100 arranged away from the core package 10 that triggers thermal runaway, thereby reducing the heating efficiency of the battery cell 100.

[0031] The heat generated by the thermal runaway core package 10 is hindered by the insulation material 30 during propagation, which can concentrate the heat generated by the thermal runaway core package 10 inside it. This makes it easier for the tabs 11 on the core package 10 to be subjected to greater heat and melt. It also helps to disconnect the circuit of the core package 10 that triggers thermal runaway in time, reducing the impact on the electrical performance of the circuit. At the same time, it also helps to further reduce the continuous heating of the thermal runaway core package 10, and further improve the structural stability and reliability of the cell 100.

[0032] Thus, by covering some of the outer surfaces of the core pack 10 with insulating material 30, and leaving some of the outer surfaces of the core pack 10 uncovered with insulating material 30, a differentiated design is achieved for at least two core packs 10 within the cell 100. This effectively extends the time between the thermal runaway of at least two core packs 10 within the cell 100, preventing simultaneous thermal runaway of all core packs 10 in the entire cell 100. This facilitates the differentiation of core packs 10 for thermal runaway handling, improving safety. Simultaneously, the insulating material 30 effectively blocks heat transfer between core packs 10, reducing the number of core packs 10 subsequently experiencing thermal runaway and slowing down the heating efficiency of the cell 100. Specifically, insulating material 30 can be placed between two adjacent core packs 10 of the cell 100. When one core pack 10 triggers thermal runaway, it can prevent heat transfer to the other core pack 10, further reducing the number of core packs 10 experiencing thermal runaway within the cell 100. Alternatively, the outer surface of the core package 10 within the cell 100 can be covered with a heat-insulating material 30, allowing the heat-insulating material 30 to provide thermal insulation between adjacent cells 100. This ensures that when a core package 10 within a cell 100 triggers thermal runaway, the heat-insulating material 30 can prevent heat from being transferred from one core package 10 of a cell 100 to another adjacent core package 10, thereby reducing the number of cells 100 in the battery pack 200 that experience thermal runaway and better slowing down the rate of temperature rise in the battery pack 200.

[0033] In one embodiment of this application, by covering at least a portion of the outer surface of at least one core package 10 with heat insulation material 30 and not providing heat insulation material 30 on at least one core package 10, a differentiated design of at least two core packages 10 in the cell 100 is achieved. The heat insulation material 30 can be used to isolate heat transfer between core packages 10, to isolate heat transfer between at least two core packages 10 within the same cell 100, to isolate heat transfer between the core packages 10 of two adjacent cells 100, or to isolate heat transfer between multiple cells 100 within the same cell 100 and between adjacent cells 100. Thus, when a cell 100 fails due to extreme conditions such as overheating, system circuit short circuit, or overcharging and over-discharging, the core package 10 covered with the thermal insulation material 30 can heat up faster and trigger thermal runaway more quickly. This helps to create a time difference between the thermal runaway triggering of multiple core packages 10 within the cell 100, preventing multiple core packages 10 from triggering thermal runaway simultaneously, thus facilitating fault handling of the cell 100. Furthermore, the thermal insulation material 30 can reduce heat transfer between core packages 10, preventing heat from gradually spreading to other core packages 10 and triggering thermal runaway in those other core packages. This helps to reduce the number of core packages 10 experiencing thermal runaway, effectively slowing down the heating rate of the cell 100, reducing the risk of fire or even explosion of the cell 100, and improving the structural stability and reliability of the cell 100.

[0034] See Figure 5 In one embodiment of this application, the thermal insulation material 30 is disposed between any two adjacent core packages 10.

[0035] In this embodiment, by placing the thermal insulation material 30 between two adjacent core packages 10, the thermal insulation material 30 can isolate the heat transfer between the two adjacent core packages 10. When some core packages 10 in the battery cell 100 trigger thermal runaway, the thermal insulation material 30 can block the heat, preventing the heat from being effectively transferred to the adjacent battery cells 100. This effectively prolongs the time difference between the thermal runaway of the two adjacent core packages 10, preventing an increasing number of battery cells 100 from experiencing thermal runaway in a short period of time. It can effectively reduce the heating rate of the battery cell 100 and further improve the structural stability and reliability of the battery cell 100.

[0036] With the thermal insulation material 30 placed between adjacent cells 100, it can isolate the heat from spreading to at least one side of the cell pack 10 that triggers thermal runaway, thereby reducing the heat transmission path between adjacent cells 100, reducing the number of cells 100 that gradually trigger thermal runaway in the battery pack 200, and further improving the structural reliability of the cells 100.

[0037] See Figures 2 to 4 In one embodiment of this application, the battery cell 100 further includes a housing 50, which has a receiving space. At least two core packages 10 are arranged in the receiving space, and at least a portion of the outer surface of the core package 10 facing the inner wall of the receiving space is covered with a heat-insulating material 30.

[0038] In this embodiment, the battery cell 100 can utilize the housing 50 to protect and insulate the core package 10, allowing the core package 10 to be stably positioned inside the housing 50 for charging and discharging processes, thus ensuring the stable operation of the battery cell 100. The housing 50 can form a sealed receiving space, and arranging at least two core packages 10 in a specific pattern within this space can reduce the impact of the external environment on the core packages 10, and also make the overall structure of the battery cell 100 more regular and compact.

[0039] By covering at least a portion of the outer surface of the battery cell 100 facing the inner wall of the housing space with heat-insulating material 30, the heat-insulating material 30 can be provided on a portion of the outer surface of the core package 10 at the arrangement of adjacent battery cells 100 in the housing 50, or the heat-insulating material 30 can be provided on the outer surface of all core packages 10 facing the inner wall of the housing space. In this way, the battery cells 100 in the battery pack 200 are arranged sequentially. When a core package 10 in some battery cells 100 triggers thermal runaway, the heat-insulating material 30 on the outer surface of the core package 10 facing the housing space can be used to slow down the transfer of heat to the housing 50, effectively slowing down the transfer of heat generated by the core package 10 that triggers thermal runaway to other battery cells 100, which helps to reduce the number of battery cells 100 that experience thermal runaway and the rate of temperature rise of the battery cells 100.

[0040] Furthermore, when the cell 100 is subjected to a certain amount of heat, or when the core package 10 is triggered to thermal runaway in an adjacent cell 100, the insulation material 30 can stably block the heat from the outside of the cell 100 from being transferred to the core package 10, thus mitigating the thermal runaway triggered by the core package 10. This better avoids the simultaneous triggering of thermal runaway in the core packages 10 of multiple cells 100, making it easier to implement thermal runaway management measures for the cell 100 more reliably, and further improving the structural stability and reliability of the cell 100.

[0041] See Figure 5 In one embodiment of this application, the core package 10 includes two opposite first surfaces 10a and two opposite second surfaces 10b, the two first surfaces 10a are connected to the two second surfaces 10b, the area of ​​the first surface 10a is larger than the area of ​​the second surface 10b, and the thermal insulation material 30 covers at least one first surface 10a.

[0042] In this embodiment, the core pack 10 can be arranged in a square-like structure. Two opposing first surfaces 10a and two opposing second surfaces 10b can be formed on the periphery of the core pack 10. Since the area of ​​the first surface 10a is larger than the area of ​​the second surface 10b, the first surfaces 10a of the core pack 10 can be arranged and installed in close proximity during the assembly of the battery cell 100, which helps to better ensure the overall structural stability of the multiple core packs 10 in the battery cell 100.

[0043] By connecting and covering the thermal insulation material 30 on at least one first surface 10a of the core package 10, the thermal insulation material 30 can be better arranged between the core packages 10, achieving a better effect of isolating heat transfer. Moreover, arranging the thermal insulation material 30 on the first surface 10a with a larger area is also conducive to achieving a better heat concentration effect, better widening the time difference between at least two cells 100 triggering thermal runaway, fully isolating heat transfer, better reducing the heating rate of the cell 100, facilitating better implementation of thermal runaway management measures for the cell 100, and further improving the structural stability and reliability of the cell 100.

[0044] See Figure 6 In one embodiment of this application, the core package 10 includes a tab 11, at least a portion of the structure of the tab 11 being covered with an insulating material 30.

[0045] In this embodiment, the core package 10 may be provided with tabs 11 that are electrically connected to the electrodes on the battery cell 100. The core package 10 may include two tabs 11, which may be connected to the positive and negative electrodes on the battery cell 100 respectively, so that the battery cell 100 can form a complete electrical circuit with the external circuit and ensure the stable operation of the battery cell 100.

[0046] By covering at least a portion of the structure of the tabs 11 of the core package 10 with heat-insulating material 30, when a short circuit occurs in the circuit within the cell 100, the short-circuit current passing through the tabs 11 easily causes the temperature of the tabs 11 to rise. At this time, the heat-insulating material 30 can concentrate the heat on the tabs 11, allowing the tabs 11 to break in time due to the high temperature, thereby enabling the cell 100 to be disconnected in time, which can play a certain short-circuit protection role. In addition, when the core package 10 triggers thermal runaway, covering at least a portion of the structure of the tabs 11 with heat-insulating material 30 can concentrate the heat generated by the thermal runaway of the core package 10 onto the tabs 11, causing the tabs 11 to break quickly under the high heat, thereby enabling the core package 10 that has triggered thermal runaway to be disconnected, reducing the impact on the circuit.

[0047] The heat insulation material 30 can cover at least part of the structure of the tab 11, or the heat insulation material 30 can wrap the entire outer surface of the tab 11. In this case, a puncture structure can be provided on the tab 11 to penetrate the heat insulation material 30, so as to ensure a stable electrical connection between the tab 11 and the electrode.

[0048] The core package 10 can cover the tab 11 connected to the positive electrode with the heat insulation material 30, or the tab 11 connected to the negative electrode with the heat insulation material 30, or all the tabs 11 of the core package 10 can be covered with the heat insulation material 30. It is preferred to cover the tab 11 connected to the positive electrode with the heat insulation material 30.

[0049] The battery cell 100 may have its tabs 11 covered with heat insulation material 30 on the outer surface of the core package 10, or it may have its tabs 11 covered with heat insulation material 30 on the outer surface of the core package 10, or it may have all the tabs 11 of the battery cell 100 covered with heat insulation material 30.

[0050] In one embodiment of this application, the thermal insulation material 30 includes at least one of polytetrafluoroethylene, polyvinylidene fluoride, and aramid fiber.

[0051] In this embodiment, the thermal insulation material 30 can be polytetrafluoroethylene foam, polytetrafluoroethylene composite material, polyvinylidene fluoride foam, or aramid fiber, etc. Using the above-mentioned materials for the thermal insulation material 30 can enable the thermal insulation material 30 to have better thermal insulation performance and better isolate the heat transfer between the cells 100, so as to better reduce the number of cells 10 that cause thermal runaway when some cells 10 trigger thermal runaway, and further improve the structural stability and reliability of the cells 100.

[0052] See Figure 7 In one embodiment of this application, the core package 10 includes a tab 11, which includes a main body portion 111 and a fusible portion 113 connected to each other. The melting point of the structural material of the fusible portion 113 is lower than the melting point of the structural material of the main body portion 111.

[0053] In this embodiment, the tab 11 of the core package 10 can be composed of a composite structure of a main body 111 and a fusible part 113. The fusible part 113 can be made of a material with a lower melting point, while the main body 111 can be made of a material with a higher melting point than the fusible part 113. Thus, when a short circuit occurs in the circuit connected to the core package 10, the heat generated by the tab 11 under the influence of current can cause the fusible part 113 of the tab 11 to break, thereby disconnecting the tab 11 from the circuit and achieving circuit breaking of the core package 10, reducing the impact of short circuits on the core package 10. When the core package 10 triggers thermal runaway and generates significant heat, the heat transferred to the tab 11 can cause the fusible part 113 to break at a high temperature, thereby quickly disconnecting the tab 11 from the circuit, which helps to reduce the impact of the core package 10 triggering thermal runaway on the circuit.

[0054] By making the tab 11 consist of a main body 111 and a fuse part 113, the tab 11 can break when subjected to a certain temperature, so that the core package 10 can be disconnected from the circuit in time, thereby reducing the impact on other core packages 10 and further improving the structural stability and reliability of the cell 100.

[0055] See Figure 8In one embodiment of this application, the core package 10 includes a first tab 11a and a second tab 11b. The core package 10 has a width direction, the length of the first tab 11a along the width direction is L1, and the length of the second tab 11b along the width direction is L2, where L1 < L2.

[0056] In this embodiment, the core package 10 can electrically connect the first tab 11a to the positive terminal of the battery cell 100 and the second tab 11b to the negative terminal of the battery cell 100, so that the core package 10 is stably connected to the circuit system of the battery cell 100. By adopting a differentiated design with different widths for the first tab 11a and the second tab 11b of the core package 10, when a fault such as a short circuit occurs in the circuit, the shorter first tab 11a in the width direction can be subjected to greater heat, thereby causing the first tab 11a to melt and disconnect the core package 10 from the circuit, which helps to better reduce the impact of the circuit on the core package 10. When the core package 10 triggers thermal runaway, the shorter first tab 11a is also more likely to break under greater heat, so that the core package 10 can better disconnect from the circuit and reduce the impact of the thermal runaway core package 10 on the circuit.

[0057] By setting the length L1 of the first tab 11a of the core package 10 to be less than the length L2 of the second tab 11b in the width direction, the tab 11 of the core package 10 is differentiated, which enables the core package 10 to be disconnected in time under certain temperature changes. This helps to reduce the mutual influence between the core package 10 and the circuit, and further improves the structural stability and reliability of the cell 100.

[0058] See Figure 9 In one embodiment of this application, the core package 10 has a tab 11. The core package 10 has a thickness direction. The tab 11 includes a first conductive segment 115 and a second conductive segment 117 connected to each other. The width of the first conductive segment 115 along the thickness direction is D1, and the width of the second conductive segment 117 along the thickness direction is D2, where D1 < D2.

[0059] In this embodiment, the core package 10 is connected to the electrodes of the battery cell 100 via tabs 11, thereby connecting the core package 10 to the circuit and ensuring the stable operation of the battery cell 100. By making the tabs 11 of the core package 10 include a first conductive segment 115 and a second conductive segment 117 with different widths, the first conductive segment 115 with a smaller width can achieve a local structural narrowing of the tab 11, giving the first conductive segment 115 and the second conductive segment 117 a certain difference in heat resistance.

[0060] Thus, when a short circuit occurs in the circuit connected to the core package 10, the narrower first conductive segment 115 experiences greater heat, making it more prone to breakage under certain high temperatures. This disconnects the core package 10 from the circuit, effectively reducing the impact of the circuit on the core package 10. Conversely, when the core package 10 triggers thermal runaway, the high heat generated by the core package 10 acts on the tab 11, easily causing the first conductive segment 115 of the tab 11 to break under high temperatures. This allows the thermally runaway core package 10 to be disconnected from the circuit in a timely manner, reducing its impact on the circuit.

[0061] By setting the width D1 of the first conductive segment 115 of the tab 11 to be smaller than the width D2 of the second conductive segment 117, a differentiated structural design of the tab 11 is achieved. Under certain temperature changes, the tab 11 can be partially broken, which can promptly trigger the disconnection between the core package 10 and the circuit. This helps to reduce the mutual influence between the core package 10 and the circuit, and further improves the structural stability and reliability of the cell 100.

[0062] See Figure 8 and Figure 9 In one embodiment of this application, the core package 10 includes tabs 11, and the tabs 11 of at least two core packages 10 are of different sizes.

[0063] In some embodiments, the battery cell 100 may have at least two core packages 10 with different widths of their tabs 11; or, the battery cell 100 may have at least two core packages 10 with different lengths of their tabs 11; or, the battery cell 100 may have at least two core packages 10 with different widths and lengths of their tabs 11. This allows for differentiated designs of at least two core packages 10. In the event of a battery cell 100 failure due to extreme conditions such as heat, system circuit short circuit, or overcharging / over-discharging, the core package 10 with the smaller tab 11 will experience tab 11 breakage in a shorter time. This facilitates a longer time difference between the thermal runaway events of at least two core packages 10, better preventing simultaneous thermal runaway of all core packages 10 in the entire battery cell 100, and further improving the structural stability and reliability of the battery cell 100.

[0064] See Figure 10This application also proposes a battery pack 200, which includes at least one battery cell 100. The specific structure of the battery cell 100 is as described in the above embodiments. Since this battery pack 200 adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be described in detail here. Multiple battery cells 100 can be arranged in the battery pack 200. The charging and discharging control of the battery pack 200 is achieved by connecting multiple battery cells 100 through a circuit. The power capacity of the battery pack 200 can be set by increasing or decreasing the number of battery cells 100. By utilizing the cooperative design of the cell pack 10 and the heat insulation material 30 in the battery cell 100, the mutual influence between the battery cells 100 can be better reduced. This reduces the number and probability of other battery cells 100 in the battery pack 200 triggering thermal runaway when some battery cells 100 trigger thermal runaway, thereby improving the structural stability and reliability of the battery pack 200.

[0065] See Figure 11 This application also proposes an energy storage device 300, which includes a battery pack 200. The specific structure of the energy storage device 300 is as described in the above embodiments. Since the battery pack 200 adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be elaborated here. The use of a certain number of battery cells 100 within the battery pack 200 to ensure power supply allows the energy storage device 300 to have better application scenarios, enabling it to supply power to various devices.

[0066] See Figure 12 This application also proposes an electricity consumption system 400, which includes an energy storage device 300. The specific structure of the electricity consumption system 400 is as described in the above embodiments. Since the energy storage device 300 incorporates all the technical solutions of all the above embodiments, it possesses at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be elaborated upon here. The electricity consumption system 400 can be a photovoltaic power generation system, a wind power generation system, a hydropower generation system, etc. It generates a certain amount of electrical energy through photovoltaic panels, wind turbines, hydropower generators, and other equipment. This electrical energy can be transmitted and stored in the energy storage device 300 through a power transmission network, thereby charging the energy storage device 300 and enabling the energy storage device 300 to stably output electrical energy to the electrical equipment.

[0067] The above description is merely an exemplary embodiment of this application and does not limit the patent scope of this application. Any equivalent structural transformations made based on the technical concept of this application and the contents of the specification and drawings of this application, or direct / indirect applications in other related technical fields, are included within the patent protection scope of this application.

Claims

1. A battery cell, characterized in that, The battery pack (10) includes at least two packs (10) and a heat insulation material (30), wherein at least a portion of the outer surface of at least one of the packs (10) is covered with the heat insulation material (30), the heat insulation material (30) is used to slow down heat transfer on the packs (10), and at least one of the packs (10) is not connected to the heat insulation material (30).

2. The battery cell as described in claim 1, characterized in that, The thermal insulation material (30) is disposed between any two adjacent core packages (10).

3. The battery cell as described in claim 1, characterized in that, The battery cell also includes a housing (50), which has a receiving space inside. At least two of the core packages (10) are arranged in the receiving space, and at least a portion of the outer surface of the core package (10) facing the inner wall of the receiving space is covered with the heat insulation material (30).

4. The battery cell as described in claim 1, characterized in that, The core package (10) includes two opposing first surfaces (10a) and two opposing second surfaces (10b), the two first surfaces (10a) are connected to the two second surfaces (10b), the area of ​​the first surface (10a) is larger than the area of ​​the second surface (10b), and the thermal insulation material (30) covers at least one of the first surfaces (10a).

5. The battery cell as described in claim 1, characterized in that, The core package (10) includes tabs (11), at least a portion of which is covered with insulating material (30).

6. The battery cell according to any one of claims 1 to 5, characterized in that, The insulation material (30) includes at least one of polytetrafluoroethylene, polyvinylidene fluoride, and aramid fiber.

7. The battery cell as described in claim 1, characterized in that, The core package (10) includes a tab (11), which includes a main body (111) and a fusible part (113) connected to each other. The melting point of the structural material of the fusible part (113) is lower than that of the structural material of the main body (111).

8. The battery cell as described in claim 1, characterized in that, The core package (10) includes a first tab (11a) and a second tab (11b). The core package (10) has a width direction. The length of the first tab (11a) along the width direction is L1, and the length of the second tab (11b) along the width direction is L2, where L1 < L2.

9. The battery cell as described in claim 1, characterized in that, The core package (10) has a tab (11), the core package (10) has a thickness direction, and the tab (11) includes a first conductive segment (115) and a second conductive segment (117) connected to each other. The width of the first conductive segment (115) along the thickness direction is D1, and the width of the second conductive segment (117) along the thickness direction is D2, where D1 < D2.

10. The battery cell as described in claim 1, characterized in that, The core package (10) includes tabs (11), and the tabs (11) of at least two of the core packages (10) are of different sizes.

11. An energy storage device (300), characterized in that, The energy storage device (300) includes a battery cell (100) as claimed in any one of claims 1 to 10.

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