Battery cell, battery device, energy storage device, energy storage system and charging network

Abstract

A battery cell, a battery device, an energy storage device, an energy storage system, and a charging network. When the capacity of the battery cell is 380-1500 Ah, the current-carrying area of a conductive section on an electrode terminal attached to an insulator is designed to be 153 mm2 or more, so that the current-carrying capacity at the conductive section is increased, and the heat generation of the conductive section under the capacity of 380-1500 Ah is reduced. Additionally, by designing the current-carrying area of the conductive section to be 153 mm2 or more, compared with a traditional structure, the heat dissipation of the surface of the conductive section can be increased. In this way, the temperature rise caused by heat generation of the conductive section is effectively reduced, and during an external short-circuit test, damage to a sealing member caused by the temperature rise on the conductive section can be reduced, which is beneficial to mitigating or reducing the occurrence of sealing failure during the external short-circuit test, and reducing the impact on the external short-circuit test, thereby improving the reliability of the battery cell.

Description

Battery cells, battery packs, energy storage devices, energy storage systems and charging networks Related applications

[0001] This application claims priority to Chinese patent application filed on December 30, 2024, application number 2024232876649, entitled "Battery cell, battery device, energy storage device, energy storage system and charging network", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of battery technology, and in particular to battery cells, battery devices, energy storage devices, energy storage systems and charging networks. Background Technology

[0003] As energy storage batteries develop towards higher energy efficiency, the requirements for their reliability are becoming increasingly stringent. To test the reliability of energy storage batteries, an external short-circuit test is typically performed, such as connecting a 1mΩ resistor externally to the battery to determine if it meets safety testing requirements. However, due to the structural design limitations of traditional energy storage batteries, seal failures are prone to occur during external short-circuit tests, affecting the overall reliability of the test. Summary of the Invention

[0004] Therefore, it is necessary to provide a battery cell, battery device, energy storage device, energy storage system, and charging network to mitigate or reduce sealing failures during external short-circuit testing and reduce the impact of external short-circuit testing.

[0005] In a first aspect, this application provides a battery cell, comprising: a housing having an outlet hole; an electrode assembly housed within the housing; electrode terminals, at least partially disposed in the outlet hole and electrically connected to the electrode assembly; and a sealing member sleeved over the electrode terminals and abutting against the wall of the outlet hole; wherein the electrode terminals include a conductive section located within the outlet hole and fitted by the sealing member, the capacity of the battery cell is denoted as C, the current-carrying area of ​​the conductive section is denoted as S1, 380Ah≤C≤1500Ah, and S1≥153mm² 2 .

[0006] For the aforementioned battery cell, when the capacity of the battery cell is 380Ah to 1500Ah, the current-carrying area of ​​the conductive section on the electrode terminal that is in contact with the insulator is designed to be 153mm². 2 The above measures increase the current-carrying capacity of the conductive section and reduce the heat generation of the conductive section in capacities ranging from 380Ah to 1500Ah. Simultaneously, the current-carrying area of ​​the conductive section is designed to be 153mm². 2Compared to traditional structures, this design increases heat dissipation from the conductive section surface. This effectively reduces the temperature rise of the conductive section, thus minimizing the risk of seal damage during external short-circuit testing. This helps mitigate or reduce seal failure during external short-circuit testing, reducing its impact and ultimately improving the reliability of the battery cells.

[0007] In some embodiments, the flow surface of the conductive segment is constructed as a circular surface, and the minimum diameter of the conductive segment is denoted as D, where 380Ah≤C≤1500Ah and D≥14mm. This design controls the minimum diameter of the conductive segment to be above 14mm, reducing the heat generation on the conductive segment; at the same time, it also increases the area of ​​the outer surface of the conductive segment, improving its heat dissipation performance.

[0008] In some embodiments, the capacity C and the minimum diameter D satisfy any of the following conditions:

[0009] (1) 380Ah≤C<600Ah, and 14mm≤D<36mm;

[0010] (2) 600Ah≤C<900Ah, and 18mm≤D<36mm;

[0011] (3) 900Ah≤C<1200Ah, and 24mm≤D<36mm;

[0012] (4) 1200Ah≤C≤1500Ah, and 30mm≤D≤36mm.

[0013] This design, based on the different capacity ranges of the battery cells, sets the diameter of the conductive section to match them. Furthermore, as the capacity range of the battery cells increases, the diameter range of the conductive section also increases. This allows the conductive section to have a more suitable overcurrent capacity at the corresponding capacity, effectively mitigating or reducing sealing failures during external short-circuit tests, facilitating the passing of external short-circuit tests, and improving the reliability of the battery cells.

[0014] In some embodiments, the capacity C and the minimum diameter D also satisfy any of the following conditions:

[0015] (1) 380Ah≤C<600Ah, and 14mm≤D<18mm;

[0016] (2) 600Ah≤C<900Ah, and 18mm≤D<24mm;

[0017] (3) 900Ah≤C<1200Ah, and 24mm≤D<30mm;

[0018] (4) 1200Ah≤C≤1500Ah, and 30mm≤D≤36mm.

[0019] This design further restricts the value of the conductive section under different capacity ranges of battery cells, effectively balancing the overcurrent capacity and space occupation of the electrode terminals, which is conducive to improving the pass rate of external short test and reducing the overall size of battery cells.

[0020] In some embodiments, the seal is configured to have a structure made of one of the following materials: fluororubber, polyamide-imide, thermoplastic polyimide, polyimide, polybenzimidazole, polyetheretherketone, and polyphenylene sulfide. This design, using one of these materials, improves the seal's temperature resistance, reduces thermal deformation during external short-circuit testing, lowers the risk of seal failure, and enhances the reliability of the battery cell.

[0021] In some embodiments, the conductive segment is constructed to be made of one of the following materials: aluminum, copper, iron, and tungsten. This design, using one of these materials, reduces the resistivity of the conductive segment, increases its current-carrying capacity, and reduces resistive heat generation, thereby improving the pass rate of external short-circuit tests.

[0022] In some embodiments, the battery cell includes an adapter that connects to the tabs and terminals of the electrode assembly. This design ensures that the current-carrying area of ​​the conductive section in the battery cell with the adapter is greater than or equal to 153 mm². 2 This facilitates the improvement of the current-carrying capacity between the electrode terminals and the tabs, while also increasing the current-carrying capacity on the conductive section, thus mitigating or reducing the risk of seal failure during external short-circuit testing.

[0023] In some embodiments, the minimum overcurrent area of ​​the adapter between the electrode assembly and the electrode terminal is denoted as S2, where S2 ≥ 20 mm. 2 This design, for battery cells with adapters that have a large current carrying capacity, controls the current carrying area of ​​the conductive section to 153 mm². 2 The above measures, while improving the conductivity of the battery cell, can effectively improve the external short-circuit test of the battery cell and mitigate or reduce the risk of seal failure during the test.

[0024] In some embodiments, the tabs of the electrode assembly are directly connected to the electrode terminals. This design, for battery cells without an adapter structure, controls the current-carrying area of ​​the conductive section to 153 mm². 2 The above measures, while improving the conductivity of the battery cell, can effectively improve the external short-circuit test of the battery cell and mitigate or reduce the risk of seal failure during the test.

[0025] In some embodiments, the electrode terminal further includes a connection end connected to the conductive segment. The connection end is located on the side of the lead-out hole facing the electrode assembly, and the connection end is electrically connected to the electrode assembly. This design, by introducing the connection end, facilitates electrical connection with the electrode assembly, which helps to improve the assembly efficiency of the battery cell.

[0026] In some embodiments, the flow area at the connection end is denoted as S3, where 500mm² 2 ≤S3≤6500mm 2 This design limits the flow area at the connection point to 500mm². 2 ~6500mm 2 This increases the outer surface area of ​​the connection end, improving its heat dissipation performance and reducing the temperature rise on the conductive section. At the same time, it also helps improve the current carrying capacity of the connection end and reduces the overall heat generation of the electrode terminals.

[0027] In some embodiments, the battery cell further includes a cover, and the electrode terminals further include leads connected to the end of the conductive segment away from the electrode assembly. The cover is sleeved on the leads and abuts against the surface of the housing facing away from the electrode assembly; wherein, the area of ​​the cross-section of the cover perpendicular to its own thickness direction is denoted as S4, 800 mm². 2 ≤S4≤3550mm 2 This design limits the cross-sectional area of ​​the cover to 500mm². 2 ~6500mm 2 The space between the two surfaces increases the outer surface area of ​​the cover, thereby increasing its heat dissipation performance and reducing the temperature rise on the conductive section. At the same time, it also helps to improve the current carrying capacity of the cover and reduce the overall heat generation of the electrode terminals.

[0028] In some embodiments, the lead-out hole includes a first segment and a second segment with a diameter larger than the first segment along its thickness direction. The second segment is located away from the electrode assembly relative to the first segment. The electrode terminal is located on the side of the first segment facing away from the electrode assembly and is fixed to the inner wall of the second segment by a seal. This design simplifies the fixing structure of the electrode terminal on the housing and helps to improve assembly efficiency.

[0029] Secondly, this application provides a battery device, which includes any of the above-mentioned battery cells.

[0030] Thirdly, this application provides an energy storage device, which includes the battery device described above.

[0031] Fourthly, this application provides an energy storage system, which includes a power conversion device and an energy storage device as described above, wherein the power conversion device is used to electrically connect the power generation device and the energy storage device.

[0032] Fifthly, this application provides a charging network, which includes charging piles and energy storage devices or energy storage systems as described above, wherein the energy storage devices are used to provide electrical energy to the charging piles. Attached Figure Description

[0033] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on the disclosed drawings without creative effort.

[0034] Figure 1 is an exploded view of a battery device provided in some embodiments of this application.

[0035] Figure 2 is a schematic diagram of the exploded structure of a battery cell provided in some embodiments of this application.

[0036] Figure 3 is a schematic diagram of the structure of an energy storage system provided in some embodiments of this application.

[0037] Figure 4 is a schematic diagram of the structure of a charging network provided in some embodiments of this application.

[0038] Figure 5 is a structural cross-sectional view of a battery cell provided in some embodiments of this application.

[0039] Figure 6 is an enlarged view of the structure at circle A in Figure 5.

[0040] Figure 7 is an exploded view of the electrode terminals and cover provided in some embodiments of this application.

[0041] Figure 8 is a partial structural diagram of a battery cell provided in some embodiments of this application.

[0042] Figure 9 is a schematic diagram of the adapter in Figure 8.

[0043] Figure 10 is a schematic diagram of the structure of the end cap and electrode terminal provided in some other embodiments of this application.

[0044] Figure 11 is a partial cross-sectional view of the structure in Figure 10 along the BB direction.

[0045] 100. Battery assembly; 10. Battery cell; 20. Housing; 201. First part; 202. Second part; 1. Outer shell; 1a. Housing; 1a1. Opening; 1b. End cap; 11. Outlet hole; 111. First hole segment; 112. Second hole segment; 2. Electrode terminal; 21. Conductive segment; 22. Connection end; 23. Outlet end; 3. Electrode assembly; 31. Electrode tab; 4. Seal; 5. Cover; 6. Adapter; 61. Main body; 62. Connection part; 200. Energy storage device; 300. Power conversion device; 400. Power generation equipment; 500. Charging pile; 600. Connector. Detailed Implementation

[0046] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0047] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0048] In the description of this application, it should be understood that if terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0049] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0050] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0051] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0052] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0053] With the development of energy storage technology, the capacity of individual battery cells in energy storage batteries is becoming increasingly larger. However, as the capacity of individual battery cells increases, their energy efficiency decreases. For example, relatively large-capacity battery cells discharge more slowly, resulting in a relatively large overall output current. According to the formula for heat dissipation in resistance, the heat loss increases relatively, leading to a relatively low energy efficiency for the battery cell. The energy efficiency of a battery cell refers to the ratio of the electrical energy output during discharge to the electrical energy input during charging.

[0054] To address this, the current-carrying capacity between the electrode assembly and the electrode terminals in a single battery cell is typically increased to reduce heat loss and improve the cell's energy efficiency. However, with this improved energy efficiency, the increased current-carrying capacity between the electrode assembly and the electrode terminals makes it easier for seal failure to occur at the electrode terminals during external short-circuit testing, thus affecting the cell's external short-circuit test requirements.

[0055] Based on this, and addressing the issue of sealing failure during external short-circuit testing in traditional battery cells, this application provides a battery cell where, when the capacity of the battery cell is 380Ah to 1500Ah, the overcurrent area of ​​the conductive section on the electrode terminals that is attached to the insulator is designed to be 153mm². 2 The above measures increase the current-carrying capacity of the conductive section and reduce the heat generation of the conductive section in capacities ranging from 380Ah to 1500Ah. Simultaneously, the current-carrying area of ​​the conductive section is designed to be 153mm². 2 Compared to traditional structures, this design increases heat dissipation from the conductive section surface. This effectively reduces the temperature rise of the conductive section, thus minimizing the risk of seal damage during external short-circuit testing. This helps mitigate or reduce seal failure during external short-circuit testing, reducing its impact and ultimately improving the reliability of the battery cells.

[0056] The battery cells disclosed in this application can be used, but are not limited to, energy storage systems, and can also be used in electrical equipment such as vehicles, ships, or aircraft. A power system for such electrical equipment can be constructed using battery cells and battery devices disclosed in this application.

[0057] The batteries disclosed in this application can be used, but are not limited to, energy storage systems, and can also be used in electrical devices such as vehicles, ships, or aircraft. A power system for such an electrical device can be constructed using the battery cells 10 and intermediate batteries disclosed in this application. Please refer to Figure 1, which is an exploded view of a battery device 100 provided in some embodiments of this application. The battery device 100 includes a housing 20 and battery cells 10, with the battery cells 10 housed within the housing 20. The housing 20 provides a space for housing the battery cells 10, and the housing 20 can adopt various structures. In some embodiments, the housing 20 may include a first portion 201 and a second portion 202, which overlap each other, and together define a space for housing the battery cells 10. The second part 202 can be a hollow structure with one open end 1a1, and the first part 201 can be a plate-like structure. The first part 201 covers the open side of the second part 202 so that the first part 201 and the second part 202 together define the accommodating space. Alternatively, the first part 201 and the second part 202 can both be hollow structures with one open end 1a1, and the open side of the first part 201 covers the open side of the second part 202. Of course, the box 20 formed by the first part 201 and the second part 202 can be of various shapes, such as a cylinder, a cuboid, etc.

[0058] In the battery device 100, there can be multiple battery cells 10, which can be connected in series, parallel, or in a mixed manner. A mixed connection means that multiple battery cells 10 are connected in both series and parallel configurations. Multiple battery cells 10 can be directly connected in series, parallel, or in a mixed manner, and then the entire assembly of the multiple battery cells 10 is housed within the housing 20. Alternatively, the battery device 100 can also consist of multiple battery cells 10 first connected in series, parallel, or in a mixed manner to form battery modules, and then these battery modules are connected in series, parallel, or in a mixed manner to form a whole, which is also housed within the housing 20. The battery device 100 may also include other structures; for example, it may include a busbar component for electrical connection between the multiple battery cells 10.

[0059] Each battery cell 10 can be a secondary battery or a primary battery; it can also be a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited to these. The battery cell 10 can be cylindrical, flat, cuboid, or other shapes.

[0060] Please refer to Figure 2, which is an exploded structural diagram of a battery cell 10 provided in some embodiments of this application. A battery cell 10 refers to the smallest unit constituting a battery device 100. As shown in Figure 3, the battery cell 10 includes an end cap 1b, a housing 1a, an electrode assembly 3, and other functional components.

[0061] End cap 1b refers to a component that covers the opening 1a1 of housing 1a to isolate the internal environment of battery cell 10 from the external environment. The shape of end cap 1b can be adapted to the shape of housing 1a to fit the housing 1a. In some embodiments, end cap 1b can be made of a material with a certain hardness and strength (such as aluminum alloy), so that end cap 1b is less prone to deformation under pressure and impact, enabling battery cell 10 to have higher structural strength and improved safety performance. Functional components such as electrode terminals 2 can be provided on end cap 1b. Electrode terminals 2 can be used for electrical connection with electrode assembly 3 to output or input electrical energy to battery cell 10. In some embodiments, end cap 1b can also be provided with a pressure relief mechanism for releasing internal pressure when the internal pressure or temperature of battery cell 10 reaches a threshold. The material of end cap 1b can also be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and this application embodiment does not impose any special limitations on this. In some embodiments, an insulating element may be provided on the inner side of the end cap 1b. The insulating element can be used to isolate the electrical connection portion 62 within the housing 1a from the end cap 1b to reduce the risk of short circuit. Exemplarily, the insulating element may be made of plastic, rubber, etc.

[0062] The housing 1a is a component used to cooperate with the end cap 1b to form the internal environment of the battery cell 10. This internal environment can accommodate the electrode assembly 3, electrolyte, and other components. The housing 1a and end cap 1b can be independent components. An opening 1a1 can be provided on the housing 1a, and the end cap 1b can be used to close the opening 1a1 to form the internal environment of the battery cell 10. Alternatively, the end cap 1b and housing 1a can be integrated. In some examples, the end cap 1b and housing 1a can form a common connecting surface before other components are inserted into the housing. When it is necessary to encapsulate the interior of the housing 1a, the end cap 1b closes the housing 1a. The housing 1a can have various shapes and sizes, such as cuboid, cylindrical, hexagonal prism, etc. In some examples, the shape of the housing 1a can be determined according to the specific shape and size of the electrode assembly 3. The material of the housing 1a can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc. This application embodiment does not impose any special limitations on this.

[0063] Electrode assembly 3 is the component in the battery cell 10 where the electrochemical reaction occurs. The casing 1a may contain one or more electrode assemblies 3. Electrode assembly 3 is mainly formed by winding or stacking positive and negative electrode sheets, and a separator is typically provided between the positive and negative electrode sheets. The portions of the positive and negative electrode sheets containing active material constitute the main body 61 of the electrode assembly 3, while the portions of the positive and negative electrode sheets without active material each constitute a tab 31. The positive and negative tabs may be located together at one end of the main body 61 or at opposite ends of the main body 61. During the charging and discharging process of the battery device 100, the positive and negative active materials react with the electrolyte, and the tabs 31 connect to the electrode terminals 2 to form a current circuit.

[0064] Please refer to Figure 3, which is a schematic diagram of the structure of an energy storage system provided in some embodiments of this application. Embodiments of this application provide an energy storage device 200, including one or more battery clusters to increase the voltage and capacity of the energy storage device 200. A battery cluster may include multiple battery devices 100, which are connected in series via a busbar to increase the voltage of the energy storage device 200. When the energy storage device 200 includes multiple battery clusters, the multiple battery clusters are connected in parallel to increase the capacity of the energy storage device 200. The energy storage device 200 can be used in energy storage power stations, wind power generation systems, solar power generation systems, mobile power systems, or temporary power supply systems, etc. The energy storage device 200 can store electrical energy as needed and output electrical energy at appropriate times. For example, the energy storage device 200 can store electrical energy during off-peak hours and provide electrical energy to relevant users or electrical equipment during peak hours. The energy storage system provided in this application can be any power system that requires the energy storage device 200. In some embodiments, the energy storage device 200 is an energy storage container or an energy storage cabinet.

[0065] In some embodiments, the energy storage device 200 may include a cabinet and one or more battery clusters housed in the cabinet.

[0066] In some embodiments, the energy storage device 200 may include modules such as a thermal management module, a main control module, a central control module, a power distribution module, and a fire protection module.

[0067] As an example, the thermal management module may include a liquid cooling unit that supplies coolant to each battery device 100 via pipelines for regulating the temperature of the individual battery cells 10.

[0068] As an example, the main control module can serve as the battery management unit for the battery cluster, used to monitor and manage the battery cluster. The main control module can monitor information such as the current, voltage, power, or temperature of the battery cluster. For instance, it can control the charging and discharging current and voltage of the battery cluster. The main control module includes modules such as an auxiliary battery management unit (SBMU) and a fusion switch.

[0069] As an example, the central control module can serve as the battery management unit of the energy storage device 200, used to monitor and manage the energy storage device 200. The central control module can monitor information such as the current, voltage, power, state of charge, or temperature of the energy storage device 200. For example, it can control the charging and discharging current and voltage of the energy storage device 200. As an example, the central control module includes modules such as an insulation monitoring module (IMM), a master battery management unit (MBMU), an Ethernet (ETH) module, and a fiber optic conversion module.

[0070] As an example, a fire protection system includes control panels, detectors, alarm devices, etc., used to detect, alarm, or extinguish fires in energy storage systems.

[0071] As an example, the power distribution unit can be used to distribute power to the power modules of the energy storage device 200.

[0072] In some embodiments, the energy storage system may include one or more energy storage devices 200 and a power converter system (PCS), wherein the power converter system 300 is connected between the power generation device 400 and the energy storage device 200. The power generation device 400 generates electrical energy, which can be stored in the energy storage device 200 through the power converter system 300, and the electrical energy stored in the energy storage device 200 can be released back to the power generation device 400 through the power converter system 300. As an example, the power generation device 400 may specifically be a power grid, a solar panel, a hydroelectric power generation device 400, a thermal power generation device 400, a wind power generation device 400, etc. The specific type of the power generation device 400 is not limited in this application.

[0073] Please refer to Figure 4, which is a schematic diagram of the structure of a charging network provided in some embodiments of this application. This application provides a charging network including a charging pile 500 and an energy storage device 200. The charging pile 500 is electrically connected to the energy storage device 200, which provides electrical energy to the charging pile 500. The charging pile 500 is electrically connected to a battery device 100 in the energy storage device 200 via a cable, and the battery device 100 can provide its stored electrical energy to the charging pile 500. The charging pile 500 has one or more connectors 600 for connecting to electrical equipment (such as a vehicle), thereby providing energy to the electrical equipment.

[0074] The energy storage device 200 can be located inside the charging pile 500 (e.g., an integrated energy storage and charging unit) or outside the charging pile 500.

[0075] According to some embodiments of this application, referring to Figures 5 to 7, this application provides a battery cell 10, which includes: a housing 1, an electrode assembly 3, electrode terminals 2, and a sealing member 4. The housing 1 has a lead-out hole 11; the electrode assembly 3 is housed within the housing 1; the electrode terminals 2 are at least partially disposed in the lead-out hole 11 and electrically connected to the electrode assembly 3; the sealing member 4 is sleeved outside the electrode terminals 2 and abuts against the wall of the lead-out hole 11. The electrode terminals 2 include a conductive segment 21 located within the lead-out hole 11 and fitted by the sealing member 4. The capacity of the battery cell 10 is denoted as C, and the current-carrying area of ​​the conductive segment 21 is denoted as S1, wherein 380Ah ≤ C ≤ 1500Ah, and S1 ≥ 153mm². 2 .

[0076] The outer casing 1 refers to the structure that provides a closed environment for the electrode assembly 3. It can be a structure without the end cap 1b, such as an enclosed aluminum shell; or it can be a combination of the casing 1a and the end cap 1b. In some specific embodiments, the outer casing 1 includes a casing 1a and an end cap 1b covering the casing 1a. The electrode assembly 3 is housed between the casing 1a and the end cap 1b, and a lead-out hole 11 is provided on the end cap 1b to fix the electrode terminal 2 on the end cap 1b.

[0077] The lead-out hole 11 refers to the structure that allows the electrode terminal 2 to connect to the electrode assembly 3 inside the housing 1. One end of the electrode terminal 2 is connected to the electrode assembly 3 in the lead-out hole 11, and the other end is used to connect to external devices. There are several ways to fix the electrode terminal 2 in the lead-out hole 11. For example, one end of the electrode terminal 2 may be located on the side of the lead-out hole 11 facing the electrode terminal 2, and the other end may be located on the side of the lead-out hole 11 away from the electrode terminal 2. In this case, the two sides of the electrode terminal 2 can be fixed to the housing 1 by welding, snap-fitting, riveting, etc.; or, one end of the electrode terminal 2 may be located on the side of the lead-out hole 11 away from the electrode terminal 2, and the other end may be located in the lead-out hole 11 without extending into the housing 1, thus simplifying the installation structure of the electrode terminal 2 on the housing 1.

[0078] Since the electrode terminal 2 is at least partially located in the lead-out hole 11, it is necessary to seal and insulate the electrode terminal 2 from the hole wall of the lead-out hole 11. For this purpose, a sealing element 4 is provided between the electrode terminal 2 and the hole wall of the lead-out hole 11. The sealing element 4 is fitted around the outer periphery of the electrode terminal 2 and abuts against the hole wall of the lead-out hole 11, thus forming a seal between the electrode terminal 2 and the lead-out hole 11.

[0079] At this point, the portion of electrode terminal 2 that is attached to seal 4 and located in lead-out hole 11 is the conductive segment 21. The conductive segment 21 can have various shapes, such as circular, elliptical, quadrilateral, or pentagonal cross-sections. When the battery cell 10 is charged and discharged, the conductive segment 21 generates heat due to its own resistance. However, due to the structural design limitations of the traditional battery cell 10, the conductive segment 21 generates excessive heat, softening or melting the seal 4 attached to it, causing seal failure and thus failing the external short circuit test requirements.

[0080] Therefore, in this embodiment, the current-carrying area of ​​the conductive section 21 is designed to be greater than or equal to 153 mm². 2 For example: it can be, but is not limited to, 153mm 2 160mm 2 200mm 2 400mm 2 500mm 2 600mm 2 700mm 2 800mm 2 900mm 2 1000mm 2 1018mm 2 This design, compared to traditional structures, increases the current-carrying capacity of the conductive section 21 and reduces heat generation. Simultaneously, it increases the surface area of ​​the conductive section 21 in contact with the seal 4, enhancing heat dissipation. This can mitigate or reduce seal failure of the battery cell 10 during external short-circuit testing, thus improving the pass rate of the external short-circuit test. The conductive section 21 can be made of various materials, such as materials with resistivity ρ ≤ 5 × 10⁻⁶. -7 Metals with a melting point of Ω·m, such as aluminum, copper, iron, tungsten, etc.; or composite materials of at least two of copper, iron, and tungsten. Simultaneously, the seal 4 can be designed as a material with certain insulating properties to isolate the conductivity between the electrode terminal 2 and the housing 1, achieving insulation protection. Furthermore, the seal 4 is also constructed as a material with a high melting point, such as a melting point greater than or equal to 250°C, to improve the temperature resistance of the seal 4. In addition to being fitted onto the conductive section 21, the seal 4 can also be fitted onto other parts of the electrode terminal 2. Since the thermal deformation of the portion of the electrode terminal 2 located outside the lead-out hole 11 on the seal 4 has little impact on the seal between the seal 4 and the hole wall of the lead-out hole 11, and on the seal between the seal 4 and the portion of the electrode terminal 2 located inside the lead-out hole 11, in this embodiment, the flow area of ​​the portion of the electrode terminal 2 located in the lead-out hole 11 is greater than or equal to 153 mm². 2 .

[0081] Additionally, it should be noted that the current-carrying area of ​​the conductive segment 21 refers to the area of ​​the cross-section of the conductive segment 21 perpendicular to its own length through which current flows. When the conductive segment 21 has a cylindrical structure, the current-carrying area of ​​the conductive segment 21 can also be the area of ​​the cross-section of the conductive segment 21 perpendicular to its own axial direction. Meanwhile, the capacity of the battery cell 10 refers to the amount of electricity discharged by the battery cell 10 under certain conditions (discharge rate, temperature, termination voltage, etc.), for example, it can be obtained by performing a discharge test using a JS-150D. The capacity of the battery cell 10 can be the actual capacity, the rated capacity, or the theoretical capacity. In some specific examples, the capacity of the battery cell 10 is the rated capacity.

[0082] In this way, the temperature rise of the conductive section 21 is effectively reduced. This reduces the damage to the seal 4 caused by the temperature rise on the conductive section 21 during the external short test, which helps to slow down or reduce the occurrence of seal failure during the external short test and improves the reliability of the battery cell 10.

[0083] According to some embodiments of this application, referring to FIG6, the flow surface of the conductive segment 21 is constructed as a circular surface, and the minimum diameter of the conductive segment 21 is denoted as D, wherein 380Ah≤C≤1500Ah, and D≥14mm.

[0084] The conductive segment 21 can be designed as a cylindrical structure, a frustum-shaped structure, or a multi-segment cylindrical structure with unequal diameters. By controlling the minimum diameter of the conductive segment 21 to be above 14mm, the heat generated on the conductive segment 21 is reduced; at the same time, the area of ​​the outer surface of the conductive segment 21 is increased, thereby improving the heat dissipation performance of the conductive segment 21.

[0085] The minimum diameter of the conductive segment 21 can be, but is not limited to, 14mm, 16mm, 18mm, 20mm, 24mm, 26mm, 28mm, 30mm, 32mm, 34mm, 36mm, 40mm, etc.

[0086] This design keeps the minimum diameter of the conductive segment 21 above 14mm, reducing the heat generated on the conductive segment 21; at the same time, it also increases the area of ​​the outer surface of the conductive segment 21, increasing its heat dissipation performance.

[0087] According to some embodiments of this application, the capacity C and the minimum diameter D satisfy any of the following conditions:

[0088] (1) 380Ah≤C<600Ah, and 14mm≤D<36mm;

[0089] (2) 600Ah≤C<900Ah, and 18mm≤D<36mm;

[0090] (3) 900Ah≤C<1200Ah, and 24mm≤D<36mm;

[0091] (4) 1200Ah≤C≤1500Ah, and 30mm≤D≤36mm.

[0092] When the capacity of the battery cell 10 is 380Ah to 600Ah, the minimum diameter D can be between 14mm and 36mm, for example, but not limited to 14mm, 16mm, 18mm, 20mm, 24mm, 28mm, 30mm, 34mm, etc. It should be noted that controlling the minimum diameter to less than 36mm, while ensuring the effective current carrying capacity of the conductive section 21, reduces the size of the conductive section 21, which is beneficial for controlling the overall size of the casing 1.

[0093] When the capacity of the battery cell 10 is 600Ah to 900Ah, the minimum diameter D can be between 18mm and 36mm, for example, but not limited to 18mm, 20mm, 24mm, 28mm, 30mm, 34mm, etc. It should be noted that the capacity of the battery cell 10 is between 600Ah and 900Ah, which is larger than that of a cell with a capacity between 600Ah and 900Ah, resulting in a relatively larger discharge current under the same conditions. Therefore, when the capacity of the battery cell 10 is between 600Ah and 900Ah, controlling the minimum diameter of the conductive section 21 to be greater than or equal to 18mm allows for a corresponding increase in the diameter of the conductive section 21, giving it better current-carrying capacity.

[0094] Furthermore, when the capacity of the battery cell 10 is between 900Ah and 1200Ah, the minimum diameter D can be between 24mm and 36mm, for example, but not limited to 24mm, 25mm, 26mm, 27mm, 28mm, 29mm, 30mm, 34mm, etc. When the capacity of the battery cell 10 is between 1200Ah and 1500Ah, the minimum diameter D can be between 30mm and 36mm, for example, but not limited to 30mm, 31mm, 32mm, 33mm, 34mm, 35mm, 36mm, etc.

[0095] With this design, the diameter of the conductive section 21 is designed to match the different capacity ranges of the battery cell 10. As the capacity range of the battery cell 10 increases, the diameter range of the conductive section 21 also increases. This allows the conductive section 21 to have a more suitable overcurrent capacity at the corresponding capacity, effectively mitigating or reducing sealing failures during external short-circuit tests, facilitating the passing of external short-circuit tests, and improving the reliability of the battery cell 10.

[0096] According to some embodiments of this application, the capacity C and the minimum diameter D also satisfy any of the following conditions:

[0097] (1) 380Ah≤C<600Ah, and 14mm≤D<18mm;

[0098] (2) 600Ah≤C<900Ah, and 18mm≤D<24mm;

[0099] (3) 900Ah≤C<1200Ah, and 24mm≤D<30mm;

[0100] (4) 1200Ah≤C≤1500Ah, and 30mm≤D≤36mm.

[0101] It can be seen that when the capacity C is 380Ah to 600Ah, the minimum diameter of the conductive section 21 is controlled between 14mm and 18mm. In this way, while meeting the effective overcurrent capacity, the diameter of the conductive section 21 is controlled as much as possible, reducing the space occupied by the electrode assembly 3 on the outer casing 1, and making it easier to effectively take into account the overall size of the battery cell 10.

[0102] Similarly, when the capacity C is 600Ah to 900Ah, the minimum diameter of the conductive section 21 is controlled between 18mm and 24mm; when the capacity C is 900Ah to 1200Ah, the minimum diameter of the conductive section 21 is controlled between 24mm and 30mm; and when the capacity C is 1200Ah to 1500Ah, the minimum diameter of the conductive section 21 is controlled between 30mm and 36mm. Thus, by further limiting the value of the conductive section 21 within different capacity ranges, the conductive section 21 effectively balances the overcurrent capacity and space occupation of the electrode terminal 2 within different capacity ranges.

[0103] This design further restricts the value of the conductive section 21 under different capacity ranges of the battery cell 10, effectively balancing the overcurrent capacity and space occupation of the electrode terminal 2, which is conducive to improving the pass rate of external short test and reducing the overall size of the battery cell 10.

[0104] According to some embodiments of this application, the seal 4 is configured to have a structure of one of the following materials: fluororubber, polyamide-imide, thermoplastic polyimide, polyimide, polybenzimidazole, polyetheretherketone, and polyphenylene sulfide.

[0105] When selecting materials for the seal 4, materials with higher melting points can be chosen, such as those with a melting point greater than or equal to 250℃ or 300℃. This can improve the temperature resistance of the seal 4, reduce the probability of deformation due to heat generation in the conductive section 21, and further reduce the probability of seal failure during external short circuit testing.

[0106] Polyamide (PAI) is a polymer with regularly alternating imide rings and amide bonds; polyimide (PI) refers to a class of polymers containing imide rings in the main chain; thermoplastic polyimide (TPI) refers to a structure formed by introducing flexible or linear chain segments into the monomer molecule of synthesized PI. Polybenzimidazoles (PBI) are rigid-chain polymers containing two nitrogen atoms in a benzo[5]-membered heterocyclic ring. Poly(ether-ether-ketone) (PEEK) is a polymer composed of repeating units containing one ketone bond and two ether bonds in the main chain structure. Polyphenylene sulfide (PPS) is a thermoplastic resin with phenyl sulfide groups in the main chain.

[0107] Of course, in some embodiments, the material of the seal 4 may also be a variety of fluororubber, polyamide-imide, thermoplastic polyimide, polyimide, polybenzimidazole, polyether ether ketone, and polyphenylene sulfide.

[0108] This design, which uses one of the following materials for the seal 4: fluororubber, polyamide-imide, thermoplastic polyimide, polyimide, polybenzimidazole, polyether ether ketone, and polyphenylene sulfide, is beneficial for improving the temperature resistance of the seal 4, reducing the thermal deformation of the seal 4 during external short-circuit testing, reducing the risk of seal failure, and improving the reliability of the battery cell 10.

[0109] According to some embodiments of this application, the conductive segment 21 is configured to have a structure of one of the following materials: aluminum, copper, iron, and tungsten.

[0110] The material for conductive segment 21 can be a material with low resistivity, for example, the resistivity of conductive segment 21 is less than or equal to ρ≤5×10. -7 Ω·m, etc.; of course, the resistivity of conductive segment 21 can also be designed to be other values.

[0111] This design, which uses aluminum, copper, iron, or tungsten as the material for conductive section 21, reduces the resistivity of conductive section 21, improves its overcurrent capacity, and reduces the generation of resistance heat, thereby improving the pass rate of external short test.

[0112] According to some embodiments of this application, referring to FIG7, the battery cell 10 includes an adapter 6, which is connected to the tab 31 of the electrode assembly 3 and the electrode terminal 2.

[0113] The adapter 6 refers to the structure that connects the tab 31 of the electrode assembly 3 and the electrode terminal 2, enabling electrical conductivity between the tab 31 and the electrode terminal 2. To improve the energy efficiency of the battery cell 10, the adapter 6 can be designed with a larger current carrying capacity. However, as the current carrying capacity of the adapter 6 increases, it becomes difficult for the adapter 6 to melt during external short-circuit testing, resulting in a large amount of heat being generated at least at the conductive section 21 of the electrode terminal 2.

[0114] In response to this, for the aforementioned adapter 6, this embodiment controls the current-carrying area of ​​the conductive section 21 to be greater than or equal to 153 mm². 2 This increases the current carrying capacity of conductive section 21, reduces heat generation, and mitigates or reduces the risk of seal failure during external short-circuit testing.

[0115] With this design, for the battery cell 10 with the adapter 6, the current-passing area of ​​the conductive section 21 is greater than or equal to 153 mm². 2 This facilitates the improvement of the current flow capacity between electrode terminal 2 and tab 31, while also increasing the current flow capacity on conductive section 21, thereby mitigating or reducing the risk of seal failure during external short-circuit testing.

[0116] According to some embodiments of this application, referring to FIG9, the minimum overcurrent area of ​​the adapter 6 between the electrode assembly 3 and the electrode terminal 2 is denoted as S2, wherein S2 ≥ 20 mm. 2 .

[0117] The minimum flow area of ​​adapter 6 is greater than or equal to 20mm². 2 For example: it can be, but is not limited to, 20mm. 2 25mm 2 30mm 2 35mm 2 40mm 2 45mm 2 50mm 2 This improves the current-carrying capacity of the adapter 6. In some specific examples, the adapter 6 includes a main body 61 and connecting portions 62 respectively located on both sides of the main body 61. Each connecting portion 62 is connected to the tab 31 of the electrode assembly 3, and the main body 61 is connected to the conductive section 21. In this case, a U-shaped structure can be formed between the main body 61 and the two connecting portions 62. The current-carrying area of ​​the main body 61 is larger than the current-carrying area of ​​each connecting portion 62, and the minimum current-carrying area of ​​each connecting portion 62 is greater than or equal to 20 mm². 2 .

[0118] When the minimum flow area of ​​adapter 6 is greater than or equal to 20mm 2At this time, its current-carrying capacity is relatively large; however, it is not easy to melt during external short-circuit testing, which may cause a large amount of heat to be generated at the conductive section 21. Therefore, for the adapter 6 with a large current-carrying capacity, the current-carrying area of ​​the conductive section 21 in this embodiment is designed to be 153mm². 2 The above can increase the current carrying capacity of the conductive section 21, reduce its conductive heat generation, and slow down or reduce the sealing failure of the seal 4 due to overheating. Specifically, in some embodiments, the conductive section 21 is constructed as a cylindrical structure, and the capacity C of the battery cell 10 and the minimum diameter D satisfy any of the following conditions: 380Ah≤C<600Ah, and 14mm≤D<18mm; 600Ah≤C<900Ah, and 18mm≤D<24mm; 900Ah≤C<1200Ah, and 24mm≤D<30mm; 1200Ah≤C≤1500Ah, and 30mm≤D≤36mm.

[0119] With this design, the current-carrying area of ​​the conductive section 21 is controlled to 153 mm² for the battery cell 10 with a large current-carrying capacity, such as the adapter 6. 2 In summary, by improving the conductivity of the battery cell 10, the external short-circuit test of the battery cell 10 can be effectively improved, and the risk of sealing failure during the test can be mitigated or reduced.

[0120] According to some embodiments of this application, the tabs 31 of the electrode assembly 3 are directly connected to the electrode terminals 2.

[0121] The tab 31 of electrode assembly 3 is directly connected to electrode terminal 2, indicating that there is no transition structure between the tab 31 and electrode terminal 2. This shortens the conductive path between the tab 31 and electrode terminal 2, improving the conductivity between them. At this time, the current-carrying area of ​​conductive section 21 is controlled at 153 mm². 2 Increasing the current carrying capacity and heat dissipation of the conductive section 21 can effectively mitigate or reduce the risk of sealing failure during external short-circuit testing, thus improving the pass rate of the test.

[0122] With this design, the current-carrying area of ​​the conductive section 21 is controlled to 153 mm² for the battery cell 10 without an adapter structure. 2 In summary, by improving the conductivity of the battery cell 10, the external short-circuit test of the battery cell 10 can be effectively improved, and the risk of sealing failure during the test can be mitigated or reduced.

[0123] According to some embodiments of this application, referring to FIG6, the electrode terminal 2 further includes a connection end 22 connected to the conductive segment 21. The connection end 22 is located on the side of the lead-out hole 11 facing the electrode assembly 3, and the connection end 22 is electrically connected to the electrode assembly 3.

[0124] The connecting end 22 refers to the component on the electrode terminal 2 used for electrical connection with the electrode assembly 3. The connecting end 22 is located on the side of the lead-out hole 11 facing the electrode assembly 3, facilitating electrical connection with the electrode assembly 3. When the connecting end 22 is located on the side of the lead-out hole 11 facing the electrode assembly 3, the connecting end 22 can be snapped or riveted to the inner wall of the housing 1 to fix the electrode terminal 2. Specifically, in some embodiments, the current-carrying area of ​​the connecting end 22 is larger than the current-carrying area of ​​the conductive section 21, which not only increases the current-carrying capacity at the connecting end 22, but also facilitates the snapping of the part of the connecting end 22 extending beyond the conductive section 21 onto one end of the lead-out hole 11.

[0125] This design introduces a connection end 22, which facilitates electrical connection with the electrode assembly 3 and helps improve the assembly efficiency of the battery cell 10.

[0126] According to some embodiments of this application, referring to FIG7, the flow area of ​​the connection end 22 is denoted as S3, wherein 500mm 2 ≤S3≤6500mm 2 .

[0127] The flow area of ​​the connection terminal 22 can be 500mm². 2 ~6500mm 2 Values ​​can be taken from, for example, 500mm, but are not limited to. 2 1000mm 2 1500mm 2 2000mm 2 2500mm 2 3000mm 2 3500mm 2 4000mm 2 4500mm 2 5000mm 2 5500mm 2 6000mm 2 6500mm 2 etc. Among them, the connecting end 22 can be constructed as a cylindrical structure.

[0128] This design controls the flow area of ​​the connection terminal 22 to 500mm². 2 ~6500mm 2 The space between the two ends increases the outer surface area of ​​the connection end 22, thereby increasing the heat dissipation performance of the connection end 22 and reducing the temperature rise on the conductive section 21. At the same time, it also helps to improve the current carrying capacity on the connection end 22 and reduce the overall heat generation of the electrode terminal 2.

[0129] According to some embodiments of this application, referring to FIG7, the battery cell 10 further includes a cover 5, and the electrode terminal 2 further includes a lead-out end 23 connected to the end of the conductive segment 21 away from the electrode assembly 3. The cover 5 is sleeved on the lead-out end 23 and abuts against the surface of the outer shell 1 facing away from the electrode assembly 3; wherein, the area of ​​the cross section of the cover 5 perpendicular to its own thickness direction is denoted as S4, 800 mm. 2 ≤S4≤3550mm 2 .

[0130] The cover 5 refers to the structure that fits over the lead-out end 23, and together with the lead-out end 23, it forms the structure for the battery cell 10 to output electrical energy. There are various ways to connect the cover 5 and the lead-out end 23, such as, but not limited to, snap-fit, riveting, welding, etc.

[0131] When the cross-sectional area of ​​cover 5 is 800mm² 2 ~3550mm 2 Values ​​can be taken from, for example, 800mm, but are not limited to. 2 1000mm 2 1500mm 2 2000mm 2 2500mm 2 3000mm 2 3500mm 2 3550mm 2 etc. Among them, the cover 5 can be constructed as a cylindrical structure.

[0132] In some embodiments, referring to Figure 6, the electrode terminal 2 includes a conductive segment 21 and a connecting end 22 and a lead-out end 23 disposed at both ends of the conductive segment 21. The cover 5 is sleeved over the lead-out end 23, and the cross-sectional area of ​​the cover 5 perpendicular to its own thickness and the flow area of ​​the connecting end 22 are both greater than the flow area of ​​the conductive segment 21. With this design, the electrode terminal 2 can be stably riveted to the outer shell 1 through the cover 5 and the connecting end 22.

[0133] This design controls the cross-sectional area of ​​cover 5 to be within 500mm². 2 ~6500mm 2 The space between the two increases the outer surface area of ​​the cover 5, thereby increasing the heat dissipation performance of the cover 5 and reducing the temperature rise on the conductive section 21. At the same time, it also helps to improve the current carrying capacity on the cover 5 and reduce the overall heat generation of the electrode terminal 2.

[0134] According to some embodiments of this application, referring to Figures 10 and 11, the lead-out hole 11 includes a first hole segment 111 and a second hole segment 112 with a diameter larger than that of the first hole segment 111 along its own thickness direction. The second hole segment 112 is away from the electrode assembly 3 relative to the first hole segment 111. The electrode terminal 2 is located on the side of the first hole segment 111 facing away from the electrode assembly 3 and is fixed to the inner wall of the second hole segment 112 by the sealing member 4.

[0135] Therefore, it can be seen that part of the electrode terminal 2 is located in the second hole section 112, and the other part extends out of the second hole section 112. At this time, when installing, the electrode terminal 2 can be fixed to the inner wall of the second hole section 112 by the sealing member 4, which simplifies the fixing structure of the electrode terminal 2 on the housing 1.

[0136] It should be noted that, in Figure 11, part of the sealing member 4 is fitted onto the portion of the electrode terminal 2 located inside the second hole section 112, and the other part is on the portion of the electrode terminal 2 located outside the second hole section 112. In this case, the minimum diameter D of the conductive section 21 should be taken as the minimum diameter of the portion of the electrode terminal 2 located inside the second hole section 112.

[0137] This design simplifies the fixing structure of the electrode terminal 2 on the housing 1, which helps to improve assembly efficiency.

[0138] According to some embodiments of this application, this application provides a battery device 100, which includes a battery cell 10 as described above.

[0139] According to some embodiments of this application, this application provides an energy storage device 200, which includes the above-mentioned battery device 100.

[0140] According to some embodiments of this application, this application provides an energy storage system, which includes a power conversion device and an energy storage device 200 as described above. The power conversion device is used to electrically connect a power generation device and an energy storage device 200.

[0141] According to some embodiments of this application, this application provides a charging network, which includes a charging pile 500 and an energy storage device 200 or more, wherein the energy storage device 200 is used to provide electrical energy to the charging pile 500.

[0142] According to some embodiments of this application, referring to Figures 5 to 11, this application provides a battery cell 10, which includes: a housing 1, an electrode assembly 3, electrode terminals 2, and a sealing element 4. The outer casing 1 has an outlet hole 11, and the electrode assembly 3 is housed within the outer casing 1. The electrode terminal 2 is at least partially disposed in the outlet hole 11 and electrically connected to the electrode assembly 3. The electrode terminal 2 includes a conductive section 21, and a sealing member 4 is sleeved on the conductive section 21 and abuts against the wall of the outlet hole 11. The capacity of the battery cell 10 is denoted as C, and the minimum diameter of the conductive section 21 is denoted as D. The capacity C and the minimum diameter D satisfy any of the following conditions: 380Ah≤C<600Ah, and 14mm≤D<18mm; 600Ah≤C<900Ah, and 18mm≤D<24mm; 900Ah≤C<1200Ah, and 24mm≤D<30mm; 1200Ah≤C≤1500Ah, and 30mm≤D≤36mm.

[0143] To make the objectives, technical solutions, and advantages of this application clearer and more concise, the following specific embodiments are used for illustration, but this application is by no means limited to these embodiments. The embodiments described below are merely preferred embodiments of this application and can be used to describe this application, but should not be construed as limiting the scope of this application. It should be noted that any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

[0144] Comparative Example 1

[0145] The experiment was conducted using a battery cell 10 based on the LFP (Lithium Iron Phosphate) system. The battery cell 10 includes an end cap 1b, a housing 1a, a seal 4, electrode terminals 2, and electrode assemblies 3. The end cap 1b is fitted onto the housing 1a. Two electrode assemblies 3 are housed between the housing 1a and the end cap 1b. The electrode terminals 2 are riveted into the lead-out holes 11 of the end cap 1b and connected to the tabs 31 of the electrode assemblies 3 via an adapter 6. The electrode terminals 2 include a conductive section 21, and the seal 4 is fitted over the conductive section 21 and abuts against the wall of the lead-out hole 11.

[0146] The sealing element 4 is made of fluororubber, the conductive section 21 is made of aluminum, and its diameter D is 10mm; the capacity C of the battery cell 10 is 400Ah.

[0147] Comparative Example 2

[0148] It is basically the same as Comparative Example 1, except that the capacity C of the battery cell 10 is 800Ah.

[0149] Comparative Example 3

[0150] It is basically the same as Comparative Example 1, except that the capacity C of the battery cell 10 is 950Ah.

[0151] Comparative Example 4

[0152] It is basically the same as Comparative Example 1, except that the capacity C of the battery cell 10 is 1200Ah.

[0153] Example 1

[0154] It is basically the same as Comparative Example 1, except that the diameter D of the conductive segment 21 is 14 mm.

[0155] Example 2

[0156] It is basically the same as Comparative Example 2, except that the diameter D of the conductive segment 21 is 14 mm.

[0157] Example 3

[0158] It is basically the same as Comparative Example 2, except that the diameter D of the conductive segment 21 is 18 mm.

[0159] Example 4

[0160] It is basically the same as Example 2, except that the material of the seal 4 is polyimide.

[0161] Example 5

[0162] It is basically the same as Comparative Example 3, except that the diameter D of the conductive segment 21 is 14 mm.

[0163] Example 6

[0164] It is basically the same as Comparative Example 3, except that the diameter D of the conductive segment 21 is 20 mm.

[0165] Example 7

[0166] It is basically the same as Comparative Example 3, except that the diameter D of the conductive segment 21 is 24 mm.

[0167] Example 8

[0168] It is basically the same as Comparative Example 4, except that the diameter D of the conductive segment 21 is 14 mm.

[0169] Example 9

[0170] It is basically the same as Comparative Example 4, except that the diameter D of the conductive segment 21 is 24 mm.

[0171] Example 10

[0172] It is basically the same as Comparative Example 4, except that the diameter D of the conductive segment 21 is 30 mm.

[0173] The battery cells 10 in Comparative Examples 1-4 and Examples 1-10 were subjected to external short-circuit testing according to the standard of "Lithium-ion Batteries for Power Storage" (GB / T 36276-2023). The specific test steps are as follows:

[0174] Short-circuit a 1mΩ resistor between the two electrode terminals 2 of the battery cell 10. Determine whether the battery cell 10 has experienced pressure leakage within 10 minutes, and record the time taken for pressure leakage and the temperature of the electrode terminals 2 during pressure leakage. Please refer to Table 1 for specific data.

[0175] The temperature test method for electrode terminal 2 is as follows: the temperature sensing wire of the thermocouple is adhered to the top of electrode terminal 2 using high-temperature resistant adhesive to record the temperature on electrode terminal 2. The method for judging pressure relief is: observe whether smoke or electrolyte leakage occurs at the edge of electrode terminal 2.

[0176] Table 1

[0177] Comparisons between Comparative Example 1 and Example 1, Comparative Example 2 and Examples 2-3, Comparative Example 3 and Examples 5-7, and Comparative Example 4 and Examples 8-10 show that, compared to a 10mm diameter conductive segment 21, a diameter of 14mm effectively reduces the pressure relief time. When the capacity of the battery cell 10 is 400Ah, this effectively solves the problem of sealing failure during external short-circuit testing. For the same battery cell 10 capacity, a larger diameter of the conductive segment 21 results in a lower temperature at the electrode terminals 2, and a longer pressure relief time during external short-circuit testing.

[0178] Meanwhile, when the capacity of battery cell 10 is 400Ah and the diameter of conductive section 21 is 14mm, battery cell 10 does not experience pressure leakage during the external short-circuit test; when the capacity of battery cell 10 is 800Ah and the diameter of conductive section 21 is 18mm, battery cell 10 does not experience pressure leakage during the external short-circuit test; when the capacity of battery cell 10 is 950Ah and the diameter of conductive section 21 is 24mm, battery cell 10 does not experience pressure leakage during the external short-circuit test; when the capacity of battery cell 10 is 1200Ah and the diameter of conductive section 21 is 30mm, battery cell 10 does not experience pressure leakage during the external short-circuit test.

[0179] Furthermore, comparing Examples 2 and 4, it can be seen that, given a battery cell capacity of 800 Ah and a conductive section diameter of 14 mm, selecting fluororubber as the material for the seal 4 results in a pressure relief time of 7 minutes; selecting polyimide as the material for the seal 4 solves the problem of pressure relief during the external short-circuit test. This indicates that selecting a seal 4 with a higher melting point can also mitigate or resolve the phenomenon of seal failure during the external short-circuit test.

[0180] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0181] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A battery cell, the battery cell comprising: The outer casing (1) has an outlet hole (11); Electrode assembly (3) is housed within the outer casing (1); Electrode terminals (2) are at least partially disposed in the lead-out holes (11) and electrically connected to the electrode assembly (3); A sealing element (4) is fitted over the electrode terminal (2) and abuts against the wall of the lead-out hole (11); The electrode terminal (2) includes a conductive section (21) located inside the lead-out hole (11) and fitted by the sealing member (4). The capacity of the battery cell is denoted as C, and the current-carrying area of ​​the conductive section (21) is denoted as S1. 380Ah≤C≤1500Ah, and S1≥153mm 2 .

2. The battery cell according to claim 1, wherein, The flow surface of the conductive segment (21) is constructed as a circular surface, and the minimum diameter of the conductive segment (21) is denoted as D, where 380Ah≤C≤1500Ah and D≥14mm.

3. The battery cell according to claim 2, wherein, The capacity C and the minimum diameter D satisfy any of the following conditions: (1) 380Ah≤C<600Ah, and 14mm≤D<36mm; (2) 600Ah≤C<900Ah, and 18mm≤D<36mm; (3) 900Ah≤C<1200Ah, and 24mm≤D<36mm; (4) 1200Ah≤C≤1500Ah, and 30mm≤D≤36mm.

4. The battery cell according to claim 3, wherein, The capacity C and the minimum diameter D also satisfy any of the following conditions: (1) 380Ah≤C<600Ah, and 14mm≤D<18mm; (2) 600Ah≤C<900Ah, and 18mm≤D<24mm; (3) 900Ah≤C<1200Ah, and 24mm≤D<30mm; (4) 1200Ah≤C≤1500Ah, and 30mm≤D≤36mm.

5. The battery cell according to any one of claims 1-4, wherein, The seal (4) is constructed to have a structure of one of the following materials: fluororubber, polyamide-imide, thermoplastic polyimide, polyimide, polybenzimidazole, polyether ether ketone, and polyphenylene sulfide.

6. The battery cell according to any one of claims 1-5, wherein, The conductive segment (21) is constructed to have a structure of one of the following materials: aluminum, copper, iron, and tungsten.

7. The battery cell according to any one of claims 1-6, wherein, The battery cell includes an adapter (6), which is connected to the tab (31) of the electrode assembly (3) and the electrode terminal (2).

8. The battery cell according to claim 7, wherein, The minimum cross-sectional area of ​​the adapter (6) between the electrode assembly (3) and the electrode terminal (2) is denoted as S2, where S2 ≥ 20 mm. 2 .

9. The battery cell according to any one of claims 1-6, wherein, The tabs (31) of the electrode assembly (3) are directly connected to the electrode terminals (2).

10. The battery cell according to any one of claims 1-9, wherein, The electrode terminal (2) further includes a connection end (22) connected to the conductive segment (21). The connection end (22) is located on the side of the lead-out hole (11) facing the electrode assembly (3). The connection end (22) is electrically connected to the electrode assembly (3).

11. The battery cell according to claim 10, wherein, The flow area of ​​the connection end (22) is denoted as S3, where 500mm² is the maximum flow area. 2 ≤S3≤6500mm 2 .

12. The battery cell according to any one of claims 1-11, wherein, The battery cell also includes a cover (5), and the electrode terminal (2) also includes a lead-out end (23) connected to the end of the conductive segment (21) away from the electrode assembly (3). The cover (5) is sleeved on the lead-out end (23) and abuts against the surface of the outer shell (1) facing away from the electrode assembly (3). The area of ​​the cross section of the cover (5) perpendicular to its own thickness direction is denoted as S4,800mm. 2 ≤S4≤3550mm 2 .

13. The battery cell according to any one of claims 1-12, wherein, The lead-out hole (11) includes a first hole segment (111) and a second hole segment (112) with a diameter larger than that of the first hole segment (111) along its own thickness direction. The second hole segment (112) is away from the electrode assembly (3) relative to the first hole segment (111). The electrode terminal (2) is located on the side of the first hole segment (111) facing away from the electrode assembly (3) and is fixed to the inner wall of the second hole segment (112) by the sealing member (4).

14. A battery device comprising a battery cell according to any one of claims 1-13.

15. An energy storage device comprising the battery device of claim 14.

16. An energy storage system comprising a power conversion device and an energy storage device as claimed in claim 15, wherein the power conversion device is used to electrically connect a power generation device and the energy storage device.

17. A charging network, the charging network comprising: Charging piles (500) ； The energy storage device as described in claim 15 or the energy storage system as described in claim 16, wherein the energy storage device is used to provide electrical energy to the charging pile (500).

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