Energy storage device and electric device

Abstract

The application relates to an energy storage device and an electric equipment. The energy storage device comprises a shell, a bare cell, a transition sheet and a cover assembly. The shell has a receiving cavity, the bare cell and the transition sheet are received in the receiving cavity, and the cover assembly seals the receiving cavity. The transition sheet is electrically connected to the bare cell and the cover assembly. The cover assembly comprises a lower insulating part and a cover. The lower insulating part is arranged on the side of the cover facing the bare cell. The lower insulating part comprises a body part and a boss part. Two boss parts are connected to the ends of the body part along a preset direction. The boss part at least partially protrudes from the side of the body part facing the bare cell. The bare cell has a tab. The tab and the transition sheet are stacked and welded. The tab and the transition sheet have a first welding area. Along the preset direction, the tab has a first end close to the boss part and a second end away from the boss part. The distance between the first end and the first welding area is smaller than the distance between the second end and the first welding area. The preset direction is the length direction of the energy storage device.

Description

Technical Field

[0001] This application relates to the field of energy storage technology, specifically to an energy storage device and an electrical appliance. Background Technology

[0002] In the field of energy storage technology, with the continuous increase in the capacity of energy storage devices, higher requirements are being placed on the design of bare cells. To achieve electrical connection between the bare cell and the end cap assembly, the overcurrent capacity of the bare cell's tabs is required to be higher. Therefore, the size of the bare cell's tabs is also larger, which may interfere with the bosses on the lower plastic parts, potentially damaging the tabs and affecting the electrical connection stability and safety performance of the energy storage device. Therefore, how to design the bare cells to ensure good safety performance of the energy storage device is an urgent problem to be solved. Utility Model Content

[0003] In view of this, this application provides an energy storage device and an electrical appliance, wherein the energy storage device has high electrical connection stability and safety performance.

[0004] This application provides an energy storage device, which includes a housing, a bare battery cell, an adapter plate, and an end cap assembly. The housing has a receiving cavity, in which the bare battery cell and the adapter plate are received. The end cap assembly closes the receiving cavity. The adapter plate is used to realize the electrical connection between the bare battery cell and the end cap assembly. The end cap assembly includes a lower insulating member and an end cap. The lower insulating member is disposed on the side of the end cap facing the bare battery cell. The lower insulating member includes a body portion and two boss portions. The two boss portions are respectively connected to the body portion along a pre-... The device has two ends in a certain direction, with the boss portion at least partially protruding from the side of the body portion facing the bare battery cell; the bare battery cell has a tab, which is stacked and welded to the adapter piece, and the tab and the adapter piece have a first solder mark area; along a predetermined direction, the tab has a first end close to the boss portion and a second end away from the boss portion, and the distance between the first end and the first solder mark area is less than the distance between the second end and the first solder mark area; wherein, the predetermined direction is the length direction of the energy storage device.

[0005] Furthermore, the electrode tab also includes a second solder mark area. The number of electrode tabs is multiple, and the multiple electrode tabs are stacked and welded together to form the second solder mark area. The first solder mark area is located within the second solder mark area.

[0006] Further, the bare cell includes a positive electrode, a separator, and a negative electrode. The positive electrode, the separator, and the negative electrode are stacked and then wound. The positive electrode includes a current collector layer, an active material layer, and an insulating coating layer. The active material layer and the insulating coating layer are disposed on the same side of the current collector layer. The current collector layer includes a connected main body and a tab, with the tab extending out from one side of the main body. The insulating coating layer includes a connected first insulating part and a second insulating part. The active material layer and the first insulating part are connected and both are disposed on the main body. The second insulating part is disposed at the end of the tab near the main body. The portion of the tab without the second insulating part has a second solder mark area. The portion of the tab without the second insulating part is also used to solder with the adapter piece to form a first solder mark area.

[0007] Furthermore, along the arrangement direction of the main body and the tabs, the first solder mark area on the tab is located at the end of the tab away from the main body.

[0008] Furthermore, the tab has a preset bend line, which is located on the side of the second solder area near the second insulating part, and the preset bend line is offset from the second insulating part.

[0009] Furthermore, along the arrangement direction of the main body and the tabs, the width d1 of the first insulating part is in the range of 0.5mm≤d1≤2.5mm.

[0010] Furthermore, along the arrangement direction of the main body and the tabs, the width d2 of the second insulating part is in the range of 0.5mm≤d2≤12.5mm.

[0011] Furthermore, along the thickness direction of the positive electrode sheet, the thickness of the insulating coating layer is less than the thickness of the active material layer.

[0012] Furthermore, the thickness h of the insulating coating layer is in the range of 10μm≤h≤150μm.

[0013] Furthermore, the peel strength T between the insulating coating layer and the current collector layer is in the range of 280 N / m ≤ T ≤ 340 N / m.

[0014] This application provides an electrical device, which includes: a device body and an energy storage device provided in this application, wherein the energy storage device supplies power to the device body.

[0015] In this application, the bare battery cell has a tab, which is stacked and welded to the adapter plate. Both the tab and the adapter plate have a first solder mark area. By welding the tab and the adapter plate together, and further welding the adapter plate to the terminal post of the end cap, an electrical connection between the bare battery cell and the end cap assembly is achieved, facilitating the transmission of electrical energy between the energy storage device and external electrical equipment or external charging equipment. Furthermore, if the first solder mark area is centered relative to the tab, the positions of the first solder mark area to the first end and the second end are equal. Given a fixed size for the tab and the lower insulating member, the tab may interfere with the boss portion. In this application, along a predetermined direction, the electrode tab has a first end near the boss and a second end away from the boss. The distance between the first end and the first solder area is smaller than the distance between the second end and the first solder area. In other words, along the predetermined direction, the distance from the first solder area to the first end is smaller. Therefore, given a fixed size for the electrode tab and the lower insulating component, the probability of interference between the electrode tab and the boss is effectively reduced. During the installation of the energy storage device, the electrode tab can be effectively prevented from being pressed by the boss, resulting in bending, damage, or even breakage. The electrode tab can still perform its electrical connection function, ensuring the electrical connection stability and safety performance of the energy storage device. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the implementation will be briefly introduced below. Obviously, the drawings described below are some implementations of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the structure of an energy storage system according to an embodiment of this application; Figure 2 This is a schematic diagram of the structure of an energy storage system according to another embodiment of this application; Figure 3 This is a schematic diagram of the structure of an energy storage system according to another embodiment of this application; Figure 4 This is a schematic diagram of the structure of an energy storage device according to an embodiment of this application; Figure 5 This is an exploded structural diagram of an energy storage device according to an embodiment of this application; Figure 6 This is a schematic diagram of the structure of the lower insulating member according to an embodiment of this application; Figure 7 This is a partial structural schematic diagram of an energy storage device according to an embodiment of this application; Figure 8 This is a cross-sectional structural diagram of a bare battery cell according to an embodiment of this application; Figure 9 This is a partial cross-sectional structural diagram of the positive electrode sheet according to an embodiment of this application; Figure 10 This is a top view of the positive electrode sheet according to an embodiment of this application; Figure 11 for Figure 10 Enlarged view of the dashed box A in the middle; Figure 12 This is a schematic diagram of the structure of an electrical device according to an embodiment of this application; Figure 13 This is a circuit block diagram of an electrical device according to an embodiment of this application.

[0018] Explanation of reference numerals in the attached figures: 100 - Energy storage system; 110 - First power conversion device; 120 - First user load; 130 - Second user load; 150 - High-voltage cable; 160 - Second power conversion device; 170 - Photovoltaic-energy storage-charging station; 180 - Automobile; 200 - Energy storage device; 210 - Housing; 211 - Reception cavity; 220 - Bare cell; 221 - Tab; 2211 - First end; 2212 - Second end; 222 - Positive electrode; 223 - Separator; 224 - Negative electrode. 225-Current collector layer, 2251-Main body, 226-Active material layer, 227-Insulating coating layer, 2271-First insulating part, 2272-Second insulating part, 228-Preset bending line, 230-Adapter piece, 240-End cap assembly, 241-Lower insulating component, 2411-Main body, 2412-Boss part, 242-End cap, 250-First soldering area, 260-Pole post, 270-Second soldering area, 300-Electrical equipment, 310-Equipment body. Detailed Implementation

[0019] 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 of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0020] The terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or apparatuses.

[0021] In this document, references to "embodiment" or "implementation" mean that a particular feature, structure, or characteristic described in connection with an embodiment or implementation may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0022] In the field of energy storage technology, as the capacity of energy storage devices continues to increase, higher requirements are being placed on the design of bare battery cells. Therefore, how to design bare battery cells to ensure that energy storage devices have good safety performance is an urgent problem to be solved.

[0023] Specifically, with the increasing capacity of energy storage devices, the size of the tabs on the bare cells is also larger to achieve electrical connection between the bare cells and the end cap assembly. This results in a larger tab width along the length of the lower plastic component, which may interfere with the bosses on the lower plastic component. During the assembly of the energy storage device, the tabs may come into contact with the bosses on the lower plastic component and be bent, damaged, or cracked, affecting the electrical connection performance of the tabs, and further impacting the electrical connection stability and safety performance of the energy storage device.

[0024] Furthermore, as the capacity of energy storage devices continues to increase, the heat generated by the energy storage devices increases, which increases the degree of thermal shrinkage of the separator of the bare cell. This may cause the positive electrode and negative electrode located on both sides of the separator to short-circuit, which in turn causes an internal short circuit in the bare cell, and further affects the electrical connection stability and safety performance of the energy storage device.

[0025] Because the energy we need is highly time- and space-dependent, in order to utilize energy rationally and improve energy efficiency, it is necessary to store one form of energy in the same way or by converting it into another, and then release it in a specific energy form for future applications. Currently, the main way to generate green electricity is to develop green energy sources such as photovoltaics and wind power to replace fossil fuels. Currently, the generation of green electricity generally relies on solar, wind, and hydropower. However, wind and solar power are generally characterized by strong intermittency and large fluctuations, which can cause grid instability, insufficient power during peak demand periods, and excessive power during off-peak periods. Unstable voltage can also damage the power grid. Therefore, insufficient electricity demand or insufficient grid capacity may lead to the problem of "wind and solar curtailment." Solving these problems requires energy storage. This involves converting electrical energy into other forms of energy through physical or chemical means and storing it. When needed, this energy can be converted back into electrical energy and released. Simply put, energy storage is like a large "power bank," storing electrical energy when solar and wind power are abundant and releasing the stored electricity when needed.

[0026] Taking electrochemical energy storage as an example, this solution provides an energy storage device 200, which is applied to the energy storage system 100. The energy storage device 200 is equipped with a set of chemical batteries, which mainly use the chemical elements in the batteries as energy storage medium. The charging and discharging process is accompanied by the chemical reaction or change of the energy storage medium. Simply put, the electrical energy generated by wind and solar energy is stored in the chemical batteries. When the use of external electrical energy reaches its peak, the stored electrical energy is released for use, or transferred to places with a shortage of electricity for use.

[0027] Current energy storage applications are quite widespread, including generation-side energy storage, grid-side energy storage, and consumption-side energy storage. The corresponding energy storage devices include: (1) Large-scale energy storage power stations (including multiple prefabricated energy storage modules) applied to wind power and photovoltaic power stations can help renewable energy power generation meet grid connection requirements and improve the utilization rate of renewable energy. As a high-quality active / reactive power regulation power source on the power supply side, the energy storage power station can realize the load matching of power in time and space, enhance the renewable energy absorption capacity, reduce instantaneous power changes, reduce the impact on the power grid, improve the problem of new energy power generation absorption, and is of great significance in power grid system backup, alleviating peak load power supply pressure and peak regulation and frequency regulation.

[0028] (2) The energy storage prefabricated cabin applied on the grid side mainly functions as peak regulation, frequency regulation and grid congestion relief. In terms of peak regulation, it can realize peak shaving and valley filling of electricity load, that is, charging the energy storage battery when the electricity load is low and releasing the stored electricity during the peak electricity load period, thereby achieving a balance between power production and consumption.

[0029] (3) Small energy storage cabinets applied to the electricity consumption side mainly function as self-consumption of electricity, peak-valley price arbitrage, capacity cost management, and improvement of power supply reliability. Depending on the application scenario, electricity consumption side energy storage can be divided into industrial and commercial energy storage cabinets, household energy storage devices 200, energy storage charging piles, etc., which are generally used in conjunction with distributed photovoltaics. Industrial and commercial users can use energy storage for peak-valley price arbitrage and capacity cost management. In the electricity market implementing peak-valley pricing, by charging the energy storage system 100 when the electricity price is low and discharging the energy storage system 100 when the electricity price is high, peak-valley price arbitrage can be achieved, reducing electricity costs. In addition, industrial enterprises subject to two-part tariffs can use the energy storage system 100 to store energy during the low electricity consumption period and discharge it during the peak load period, thereby reducing peak power and the maximum demand declared, and achieving the goal of reducing capacity electricity costs. Household photovoltaics with energy storage can improve the level of self-consumption of electricity. Due to high electricity prices and poor power supply stability, the demand for household photovoltaic installations is driven. Given that photovoltaic power generation occurs during the day, while user load is generally higher at night, configuring energy storage can better utilize photovoltaic power, improve self-consumption levels, and reduce electricity costs. Furthermore, energy storage is needed in areas such as communication base stations and data centers for backup power.

[0030] In some embodiments, see Figure 1 , Figure 1 This is a schematic diagram of the structure of an energy storage system 100 according to an embodiment of this application. Figure 1 The embodiments are illustrated using a home energy storage scenario in user-side energy storage as an example. The energy storage device 200 in this application is not limited to an energy storage box in a home energy storage scenario.

[0031] This application provides an energy storage system 100, which includes a first power conversion device 110 (photovoltaic panel), a first user load 120 (household lighting fixtures), a second user load 130 (e.g., household appliances such as air conditioners), and the energy storage device 200 of this application. The energy storage device 200 is a small energy storage box that can be wall-mounted on an outdoor wall. However, the energy storage device 200 is not limited to wall mounting and can also be placed in a user's residence in other ways. Specifically, the photovoltaic panel can convert solar energy into electrical energy during periods of low electricity prices, and the energy storage device 200 is used to store this electrical energy and supply it to lighting fixtures and household appliances during periods of high electricity prices, or to provide power during power outages / power failures.

[0032] Optionally, the first power conversion device 110 may include, but is not limited to, a photovoltaic panel, and the first power conversion device 110 can convert at least one of solar energy, light energy, wind energy, thermal energy, tidal energy, biomass energy and mechanical energy into electrical energy.

[0033] In some embodiments, see Figure 2 , Figure 2This is a schematic diagram of the structure of an energy storage system 100 according to another embodiment of this application, and this application Figure 2 The embodiments are illustrated using a shared energy storage scenario on the power generation / distribution side as an example. The energy storage device 200 in this application is not limited to a prefabricated energy storage module in a power generation / distribution energy storage scenario.

[0034] This application provides an energy storage system 100, which includes: a high-voltage cable 150, a first power conversion device 110, a second power conversion device 160, and an energy storage device 200 provided in this application. In some embodiments of the power generation scenario, the second power conversion device 160 can be a wind power conversion device. Since the electricity generated by wind power conversion is volatile, random, and intermittent, the unstable electricity output by the wind power conversion device can be stored in the energy storage device 200 through grid connection. The energy storage device 200 is connected to the high-voltage cable and outputs smooth electricity to the power consumption side of the distribution network, realizing peak shaving and frequency regulation, and stable grid operation; or, wind power... The conversion device is always connected to the high-voltage cable. Under normal power generation conditions, the power output of the wind power conversion device is supplied to the power consumption side of the distribution network through the high-voltage cable. When the current power load is low and the wind power conversion device generates excess power, the excess power is first stored in the energy storage device 200 to reduce the curtailment rate of wind and solar power and improve the problem of new energy power generation consumption. When the power load is high, the power grid issues an instruction to transmit the power stored in the energy storage device 200 together with the high-voltage cable 150 in grid-connected mode to supply power to the power consumption side. This provides the power grid with various services such as peak shaving, frequency regulation, and backup, giving full play to the peak shaving role of the power grid, promoting peak shaving and valley filling, and alleviating the power supply pressure of the power grid.

[0035] In some embodiments on the distribution network side, the first power conversion device 110 can be a photovoltaic panel, and the energy storage device 200 is connected to the high-voltage cable 150 and installed downstream of the high-voltage cable 150 between the user load and the photovoltaic power conversion device. The electrical energy output by the photovoltaic power conversion device is stored in the energy storage device 200, which can respond in a timely manner to act as a backup power source when the power grid / distribution network fails; or, it can provide power supply support to alleviate line congestion when the high-voltage cable 150 transmission line is blocked, and to delay the economic pressure caused by the expansion of the power grid / distribution capacity when the power grid is planned to be expanded.

[0036] Optionally, the first power conversion device 110 may include, but is not limited to, a wind power conversion device, and the second power conversion device 160 may include, but is not limited to, a photovoltaic panel. The first power conversion device 110 and the second power conversion device 160 can convert at least one of solar energy, light energy, wind energy, thermal energy, tidal energy, biomass energy, and mechanical energy into electrical energy.

[0037] In some embodiments, see Figure 3 , Figure 3This is a schematic diagram of the structure of an energy storage system 100 according to another embodiment of this application, and this application Figure 3 The embodiments are illustrated using an industrial and commercial energy storage scenario as an example. The energy storage device 200 in this application is not limited to an energy storage cabinet in an industrial and commercial energy storage scenario.

[0038] This application provides an energy storage system 100, which includes: an energy storage device 200, a high-voltage cable 150, a factory equipped with a first power conversion device 110, a photovoltaic-energy storage-charging station 170 equipped with a second power conversion device 160, and a vehicle 180. In some embodiments of industrial and commercial scenarios, the first power conversion device 110 can be a photovoltaic panel, which converts solar energy into electrical energy and stores it in the energy storage device 200 in the factory. In the event of a power grid failure, the energy storage device 200 provides power to ensure the safe and stable operation of the factory without interruption. Alternatively, when the factory's power load is high, the power grid issues an instruction to transmit the electricity stored in the energy storage device 200 in conjunction with the high-voltage cable 150 in a grid-connected mode to supply the factory with electricity, providing various services such as peak shaving / frequency regulation and backup for the power grid operation. In addition, the second power conversion device 160 can also be a photovoltaic panel, which converts solar energy into electrical energy and stores it in the energy storage device 200 of the photovoltaic-energy storage-charging station 170, directly charging the vehicle 180 through the photovoltaic-energy storage-charging station 170, which is fast and convenient.

[0039] Optionally, the first power conversion device 110 and the second power conversion device 160 may include, but are not limited to, photovoltaic panels. The first power conversion device 110 can convert at least one of solar energy, light energy, wind energy, thermal energy, tidal energy, biomass energy, and mechanical energy into electrical energy.

[0040] Optionally, the energy storage device 200 may include, but is not limited to, energy storage applications such as energy storage power stations, hydropower / thermal / wind power generation systems, solar power generation systems, mobile power systems, smart home systems, or temporary power supply systems, and may also be applied in multiple fields such as data centers, military equipment, aerospace, charging piles, and electric vehicles.

[0041] Optionally, the energy storage device 200 may include, but is not limited to, single-cell batteries, or battery modules, battery packs, battery clusters, power banks, energy storage cabinets / prefabricated energy storage compartments, and other battery integrated systems composed of single-cell batteries. The actual application form of the energy storage device 200 provided in this application embodiment may be, but is not limited to, the listed products, and may also be other application forms. This application embodiment does not strictly limit the application form of the energy storage device 200. This application embodiment only uses a multi-cell battery of the energy storage device 200 as an example for illustration.

[0042] Optionally, the individual battery cells constituting the energy storage device 200 can be, but are not limited to, at least one of cylindrical, prismatic, prismatic, or other shaped batteries.

[0043] Optionally, the energy storage device 200 may include, but is not limited to, energy storage applications such as energy storage power stations, hydropower / thermal / wind power generation systems, solar power generation systems, mobile power systems, smart home systems, or temporary power supply systems, and may also be applied in multiple fields such as data centers, military equipment, aerospace, charging piles, and electric vehicles.

[0044] Optionally, the energy storage device 200 may include battery modules, battery packs, battery clusters, mobile power supplies, energy storage cabinets / prefabricated energy storage compartments, and other battery integrated systems composed of individual batteries. The actual application form of the energy storage device 200 provided in this application embodiment may be, but is not limited to, the listed products, and may also be other application forms. This application embodiment does not strictly limit the application form of the energy storage device 200.

[0045] Alternatively, the single cell is not limited to at least one of cylindrical, square, prismatic, or other shaped cells.

[0046] Optionally, the single cell can be a rechargeable battery, which refers to a single cell that can be recharged after discharge to activate the active materials and continue to be used. The single cell can be a lithium-ion battery, sodium-ion battery, sodium-lithium-ion battery, lithium metal battery, sodium metal battery, lithium-sulfur battery, magnesium-ion battery, nickel-metal hydride battery, nickel-cadmium battery, lead-acid battery, etc., and this application does not specifically limit it.

[0047] Please see Figures 4 to 7 This application provides an energy storage device 200, which includes a housing 210, a bare battery cell 220, an adapter piece 230, and an end cap assembly 240. The housing 210 has a receiving cavity 211, in which the bare battery cell 220 and the adapter piece 230 are received. The end cap assembly 240 closes the receiving cavity 211. The adapter piece 230 is used to realize the electrical connection between the bare battery cell 220 and the end cap assembly 240. The end cap assembly 240 includes a lower insulating member 241 and an end cap 242. The lower insulating member 241 is disposed on the side of the end cap 242 facing the bare battery cell 220. The lower insulating member 241 includes a body portion 2411 and two boss portions 2412. The two boss portions 2412 are respectively connected to the body portion 2411 along a predetermined direction (e.g., Figure 5The protrusion 2412 protrudes at least partially from the side of the body 2411 facing the bare cell 220 at two ends (as shown in the X direction). The bare cell 220 has a tab 221, which is stacked and welded to the adapter piece 230. The tab 221 and the adapter piece 230 have a first solder area 250. Along a preset direction, the tab 221 has a first end 2211 close to the protrusion 2412 and a second end 2212 away from the protrusion 2412. The distance between the first end 2211 and the first solder area 250 is less than the distance between the second end 2212 and the first solder area 250. The preset direction is the length direction of the energy storage device 200.

[0048] Understandably, along the height direction of the energy storage device 200, the adapter piece 230 is located between the end cap assembly 240 and the bare cell 220.

[0049] Understandably, along the preset direction, the first solder area 250 is offset from the central area of ​​the tab 221.

[0050] Understandably, both the tab 221 and the adapter piece 230 have the first solder area 250, which is formed by laser welding the tab 221 and the adapter piece 230 together.

[0051] Understandably, the bare battery cell 220 includes a positive electrode 222, a separator 223, and a negative electrode 224, which are stacked and then wound together. The tab 221 includes a positive electrode tab and a negative electrode tab, the positive electrode 222 includes the positive electrode tab, and the negative electrode 224 includes the negative electrode tab.

[0052] In this embodiment, the bare battery cell 220 has a tab 221, which is stacked and welded to the adapter piece 230. The tab 221 and the adapter piece 230 have a first solder mark area 250. By welding the tab 221 and the adapter piece 230 together, and further welding the adapter piece 230 to the terminal post 260 of the end cap 242, an electrical connection is achieved between the bare battery cell 220 and the end cap assembly 240, facilitating the transmission of electrical energy between the energy storage device 200 and external electrical equipment 300 or external charging equipment. Furthermore, if the first solder mark area 250 is centrally located relative to the tab 221, the positions of the first solder mark area 250 to the first end 2211 and the second end 2212 are equal. Given a fixed size for the tab 221 and the lower insulating member 241, the tab 221 may interfere with the boss portion 2412. In this application, along a preset direction, the tab 221 has a first end 2211 close to the boss 2412 and a second end 2212 away from the boss 2412. The distance between the first end 2211 and the first solder area 250 is smaller than the distance between the second end 2212 and the first solder area 250. In other words, along the preset direction, the distance from the first solder area 250 to the first end 2211 is smaller. Therefore, given that the dimensions of the tab 221 and the lower insulating member 241 are constant, the probability of interference between the tab 221 and the boss 2412 is effectively reduced. During the installation of the energy storage device 200, the tab 221 can be effectively prevented from being pressed by the boss 2412, resulting in bending, damage, or even breakage. The tab 221 can still perform its electrical connection function, ensuring the electrical connection stability and safety performance of the energy storage device 200.

[0053] Optionally, the end cap assembly 240 further includes a terminal post 260 and an upper insulating member. The upper insulating member is installed on the end cap 242, and the terminal post 260 passes through the upper insulating member. The upper insulating member is used to achieve insulation between the terminal post 260 and the end cap 242. The terminal post 260 is also welded to the adapter piece 230 to achieve electrical connection with the bare cell 220 through the adapter piece 230.

[0054] Understandably, the electrode post 260 includes a positive electrode post and a negative electrode post, the positive electrode post being electrically connected to the tab 221 of the positive electrode plate 222, and the negative electrode post being electrically connected to the tab 221 of the negative electrode plate 224.

[0055] Optionally, the number of bare cells 220 is multiple, arranged along a specific direction (e.g., Figure 5On the Y-direction (as shown in the middle), the plurality of bare cells 220 are arranged sequentially, wherein the specific direction is the width direction of the energy storage device 200, and the preset direction intersects with the specific direction.

[0056] Optionally, in some embodiments, the preset direction is perpendicular to the specific direction.

[0057] Understandably, the dimension of the energy storage device 200 in the preset direction is larger than the dimension of the energy storage device 200 in the specific direction.

[0058] In the terminology of this application, "multiple" means two or more, and can be, but is not limited to, two, three, four, five, six, etc.

[0059] Optionally, in some embodiments, the tab 221 is an aluminum foil sheet; in other embodiments, the tab 221 is a copper foil sheet.

[0060] In some embodiments, the tab 221 further includes a second solder area 270, and the number of tabs 221 is multiple, the multiple tabs 221 are stacked and welded together to form the second solder area 270, and the first solder area 250 is located within the second solder area 270.

[0061] Understandably, the multiple layers of tabs 221 are connected by ultrasonic welding, and the second weld mark area 270 is a weld mark formed by ultrasonic welding of the multiple layers of tabs 221.

[0062] When the energy storage device 200 has a large capacity, in order to meet the large overcurrent requirements, the number of tabs 221 is multi-layered and the area of ​​the tabs 221 is large. If the tabs 221 are directly welded to the adapter piece 230, the weld may be unreliable. In this embodiment, the multiple layers of tabs 221 are stacked and welded together. On the one hand, the multiple layers of tabs 221 can be initially welded into a relatively regular foil group, avoiding the welding accuracy between the tabs 221 and the adapter piece 230 due to misalignment or offset of the tabs 221. On the other hand, the multiple layers of tabs 221 are made of extremely thin foil sheets, and there are likely to be tiny gaps between the foil sheets. By connecting the multiple layers of tabs 221 through ultrasonic welding, the high-frequency vibration and pressure can make the multiple layers of tabs 221 fit tightly together, reducing the tiny gaps between the multiple layers of tabs 221. During the laser welding process between the tabs 221 and the adapter plate 230, if the gaps between the multiple layers of tabs 221 are too large, it may cause laser energy dispersion, resulting in a weak weld. This embodiment of the application pre-welds the multiple layers of tabs 221 to control the gaps between them to a very small range, meeting the stringent requirements of laser welding for interface fit. This ensures a strong weld between the tabs 221 and the adapter plate 230, further guaranteeing the electrical connection stability and safety performance of the energy storage device 200.

[0063] Optionally, in one specific embodiment, the second solder area 270 is rectangular, and the dimensions of the second solder area 270 are 12mm × 35mm, that is, the width of the second solder area 270 is 12mm and the length is 35mm.

[0064] Please see also Figures 8 to 11In some embodiments, the bare cell 220 includes a positive electrode 222, a separator 223, and a negative electrode 224. The positive electrode 222, the separator 223, and the negative electrode 224 are stacked and then wound. The positive electrode 222 includes a current collector layer 225, an active material layer 226, and an insulating coating layer 227. The active material layer 226 and the insulating coating layer 227 are disposed on the same side of the current collector layer 225. The current collector layer 225 includes a connected main body portion 2251 and a tab 221, with the tab 221 extending out of the main body portion 2251. On one side; the insulating coating layer 227 includes a first insulating portion 2271 and a second insulating portion 2272 connected together, the active material layer 226 and the first insulating portion 2271 are connected and both are disposed on the main body portion 2251; the second insulating portion 2272 is disposed at one end of the tab 221 near the main body portion 2251, the portion of the tab 221 without the second insulating portion 2272 has the second solder area 270, and the portion of the tab 221 without the second insulating portion 2272 is also used to weld with the adapter piece 230 to form the first solder area 250.

[0065] Understandably, the active material layer 226 and the insulating coating layer 227 are disposed in the same layer.

[0066] Understandably, in some embodiments, the active material layer 226 is disposed on one side of the current collector layer 225; in other embodiments, the active material layer 226 has two layers, and the two active material layers 226 are respectively disposed on opposite sides of the current collector layer 225.

[0067] Understandably, the portion of the tab 221 without the second insulating portion 2272 is larger than the portion of the second solder area 270, so as to facilitate the soldering connection of multiple layers of the tabs without damaging the second insulating portion 2272.

[0068] Understandably, the portion of the tab 221 without the second insulating portion 2272 is larger than the first solder area 250, so as to facilitate the soldering connection between the tab 221 and the adapter piece 230 without damaging the second insulating portion 2272.

[0069] Understandably, both the first solder mark area 250 and the second solder mark area 270 are located in the portion of the tab 221 where the second insulating portion 2272 is not provided.

[0070] In this embodiment, the active material layer 226 and the first insulating portion 2271 are connected and both disposed on the main body portion 2251. In other words, on the main body portion 2251, there is a certain gap between the coating area of ​​the active material layer 226 and the edge of the main body portion 2251 near the tab 221. In the bare cell 220, the size of the negative electrode 224 is usually larger than the size of the positive electrode 222. When the separator 223 located between the positive electrode 222 and the negative electrode 224 shrinks, if the coating area of ​​the active material layer 226 is not spaced from the edge of the main body portion 2251 near the tab 221, the active material layer 226 will directly contact the negative electrode material layer or negative electrode current collector of the negative electrode 224, which may cause a short circuit. By providing the first insulating portion 2271 and the second insulating portion 2272, the positive electrode 222 and the negative electrode 224 are insulated and isolated, preventing short circuit between the positive electrode 222 and the negative electrode 224 and improving the safety performance of the energy storage device 200. Furthermore, the end of the tab 221 near the main body 2251 has the second insulating portion 2272. The portion of the tab 221 without the second insulating portion 2272 has the second solder mark area 270. The portion of the tab 221 without the second insulating portion 2272 is also used to weld with the adapter piece 230 to form the first solder mark area 250. Similarly, the second insulating portion 2272 can prevent the current collector layer 225 from directly contacting the negative electrode 224 and short-circuiting. Furthermore, when the tab 221 of the bare cell 220 is soldered to the adapter piece 230, the end of the tab 221 with the second solder area 270 is bent. The second solder area 270 and the second insulating part 2272 are staggered, which can prevent the second solder area 270 and the second insulating part 2272 from affecting each other. Firstly, bending of the second insulating part 2272 can be avoided, thereby preventing the second insulating part 2272 from losing its insulating properties due to powder shedding. Secondly, it can also prevent the insulating coating layer 227 from being affected during high-temperature soldering, thereby ensuring the insulating performance of the second insulating part 2272, thereby preventing internal short-circuit failure of the energy storage device 200 and improving the safety performance of the energy storage device 200. Secondly, since the second insulating portion 2272 is stacked with the current collector layer 225, the portion of the tab 221 where the second insulating portion 2272 is located is relatively thick. If the first soldering area 250 and the second soldering area 270 are located in the area where the second insulating portion 2272 is located, the excessive thickness may affect the manufacturing performance. In this embodiment, by staggering the second insulating portion 2272 with the first soldering area 250 and the second soldering area 270, the stability of the welding connection between the tab 221 and the adapter piece 230 can be improved, further enhancing the safety performance of the energy storage device 200.

[0071] In some embodiments, along the arrangement direction of the main body portion 2251 and the tab 221, the first solder area 250 on the tab 221 is located at the end of the tab 221 away from the main body portion 2251.

[0072] In this embodiment, after the bare cell 220 is welded to the adapter piece 230, the tab 221 extends beyond the bare cell 220 and is bent. Along the arrangement direction of the main body 2251 and the tab 221, the first solder area 250 on the tab 221 is located at the end of the tab 221 away from the main body 2251, allowing the tab 221 to have a larger bending angle. This prevents the tab 221 from being excessively bent and breaking, extending the safety performance of the tab 221; it also avoids affecting the overcurrent capacity of the tab 221, improving the safety performance of the energy storage device 200. Furthermore, when there are multiple bare cells 220, setting the first solder area 250 to a position offset from the center of the tab 221 along the specific direction facilitates the welding of the multiple bare cells 220, improving the assembly performance of the energy storage device 200.

[0073] In some embodiments, the tab 221 has a preset bend line 228, which is located on the side of the second solder area 270 near the second insulating portion 2272, and the preset bend line 228 is offset from the second insulating portion 2272.

[0074] Understandably, the plane where the second solder area 270 is located is perpendicular to the height direction of the energy storage device 200, the height direction of the bare cell 220 is parallel to the height direction of the energy storage device 200, and the tab 221 is bent to connect the main body 2251 and the adapter piece 230 to form the preset bending line 228.

[0075] In this embodiment, during the installation of the energy storage device 200, when multiple bare cells 220 need to be placed in the receiving cavity 211, the tab 221 is located on the side of the housing 210 near the end cap 242. The tab 221 needs to be bent to combine two adjacent bare cells 220, so that the entire assembly of multiple bare cells 220 can be housed in the receiving cavity 211, thereby giving the tab 221 a preset bending line 228. The multiple layers of tabs 221 are ultrasonically welded to form the second solder area 270. The area where the second solder area 270 is located is more rigid than other areas of the tabs 221, so that when the tabs 221 are connected to the main body 2251 and the adapter piece 230 respectively, the tabs 221 bend and form the preset bending line 228 along the side of the second solder area 270 near the second insulating part 2272. The preset bending line 228 is staggered from the second insulating part 2272, which can avoid bending the second insulating part 2272 and causing the insulating material in the second insulating part 2272 to fall off, thereby avoiding short circuit failure inside the bare cell 220. The energy storage device 200 has better safety performance.

[0076] In some embodiments, along the arrangement direction of the main body 2251 and the tab 221, the width d1 of the first insulating portion 2271 is in the range of 0.5mm≤d1≤2.5mm.

[0077] Specifically, the width d1 of the first insulating portion 2271 can be, but is not limited to, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 1.1mm, 1.3mm, 1.5mm, 1.6mm, 1.8mm, 2mm, 2.1mm, 2.2mm, 2.4mm, and 2.5mm.

[0078] Understandably, in the energy storage device 200, before the tab 221 is bent, the arrangement direction of the main body 2251 and the tab 221 is parallel to the height direction of the energy storage device 200. The main body 2251 of the plurality of positive electrode plates 222 are wound with the diaphragm 223 and the negative electrode plate 224 to form the bare cell 220 as a whole. The tab 221 extends out of the main body 2251 on the side near the end cap 242.

[0079] In this embodiment, along the arrangement direction of the main body 2251 and the tabs 221, when the width d1 of the first insulating portion 2271 satisfies the range of 0.5mm≤d1≤2.5mm, the width of the first insulating portion 2271 is within a reasonable range. On the one hand, when the diaphragm 223 undergoes thermal shrinkage, the first insulating portion 2271 can act as a barrier layer, preventing direct exposure of the active material layer 226 and causing the active material layer 226 to short-circuit with the negative electrode 224, thereby improving the safety performance of the energy storage device 200. On the other hand, it can prevent the width of the first insulating portion 2271 from being too large and occupying too much space in the main body 2251, thus ensuring that the width of the active material layer 226 disposed on the main body 2251 is also large enough, and the bare cell 220 has a large capacity. When the width d1 of the first insulating portion 2271 is too large, the first insulating portion 2271 occupies too much space in the main body portion 2251, thereby making the width of the active material layer 226 disposed on the main body portion 2251 smaller, reducing the capacity of the bare cell 220. When the width d1 of the first insulating portion 2271 is too small, when the separator 223 undergoes thermal shrinkage, the active material layer 226 is easily directly exposed and short-circuited to the negative electrode plate 224, reducing the safety performance of the energy storage device 200.

[0080] Preferably, the width d1 of the first insulating part 2271 is in the range of 1mm≤d1≤2mm.

[0081] In some embodiments, along the arrangement direction of the main body 2251 and the tab 221, the width d2 of the second insulating portion 2272 is in the range of 0.5mm≤d2≤12.5mm.

[0082] Specifically, the width d2 of the second insulating portion 2272 can be, but is not limited to, 0.5mm, 1mm, 1.5mm, 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, 12mm and 12.5mm.

[0083] In this embodiment, along the arrangement direction of the main body 2251 and the tab 221, when the width d2 of the second insulating portion 2272 satisfies the range of 0.5mm≤d2≤12.5mm, the width of the second insulating portion 2272 is within a reasonable range. On the one hand, this can reduce the die-cutting accuracy of the positive electrode 222 during its preparation. Furthermore, the second insulating portion 2272 can fully exert its insulating function, preventing short-circuit connections between the positive electrode 222 and the negative electrode 224. On the other hand, it can prevent the second insulating portion 2272 from occupying too much space on the tab 221, thus affecting the welding of the tab 221 to the adapter piece 230 and ensuring the current-carrying capacity of the tab 221. When the width d2 of the second insulating portion 2272 is too large, the area of ​​the tab 221 used for welding with the adapter piece 230 is correspondingly reduced. This may result in the first solder area 250 and / or the second solder area 270 being partially located in the second insulating portion 2272. This could lead to a decrease in the current carrying capacity of the tab 221 and may cause the insulating material of the second insulating portion 2272 to fall off, resulting in a loss of insulation performance. In addition, since the second insulating portion 2272 occupies a certain thickness, it may also affect the bending of the tab 221, thereby increasing the risk of damage to the tab 221. When the width d2 of the second insulating portion 2272 is too small, the die-cutting precision of the positive electrode 222 increases during the preparation of the positive electrode 222, increasing the difficulty of preparing the positive electrode 222.

[0084] Preferably, along the arrangement direction of the main body 2251 and the tab 221, the width d2 of the second insulating part 2272 is in the range of 1mm≤d2≤8mm.

[0085] Optionally, along the arrangement direction of the main body 2251 and the tab 221, the sum of the width of the first insulating part 2271 and the width of the second insulating part 2272, i.e., d1+d2, satisfies the range: 1mm≤d1+d2≤15mm.

[0086] Preferably, along the arrangement direction of the main body 2251 and the tab 221, the sum of the width of the first insulating part 2271 and the width of the second insulating part 2272, i.e., d1+d2, satisfies the range: 2mm≤d1+d2≤10mm.

[0087] In some embodiments, along the thickness direction of the positive electrode 222, the thickness of the insulating coating layer 227 is less than the thickness of the active material layer 226.

[0088] In this embodiment, along the thickness direction of the positive electrode 222, the thickness of the insulating coating layer 227 is less than the thickness of the active material layer 226. This ensures that the thickness of the active material layer 226 is within a reasonable range, allowing the positive electrode 222 to have a sufficiently large capacity. Furthermore, the thickness of the insulating coating layer 227 is also within a reasonable range, allowing it to fully utilize its insulating properties to prevent short-circuit connections between the positive electrode 222 and the negative electrode 224. Additionally, it avoids increasing die-cutting difficulty due to excessive thickness of the insulating coating layer 227, thus improving the fabrication performance of the positive electrode 222.

[0089] In some embodiments, the thickness h of the insulating coating layer 227 is in the range of 10 μm ≤ h ≤ 150 μm.

[0090] Specifically, the thickness h of the insulating coating layer 227 can be, but is not limited to, 10μm, 15μm, 20μm, 25μm, 30μm, 35μm, 40μm, 50μm, 60μm, 70μm, 75μm, 80μm, 90μm, 100μm, 110μm, 120μm, 130μm, 140μm, and 150μm.

[0091] In this embodiment, when the thickness h of the insulating coating layer 227 meets the range of 10μm≤h≤150μm, the thickness of the insulating coating layer 227 is within a reasonable range. The insulating coating layer 227 can fully utilize its insulating properties to prevent short-circuit connection between the positive electrode 222 and the negative electrode 224. Furthermore, it avoids increasing the die-cutting difficulty due to excessive thickness of the insulating coating layer 227, thus improving the fabrication performance of the positive electrode 222. When the thickness of the insulating coating layer 227 is too large, the difficulty of die-cutting the portion coated with the insulating coating layer 227 increases during the fabrication of the positive electrode 222, reducing the fabrication performance of the positive electrode 222. In addition, the insulating coating layer 227 may crack, causing it to lose its insulating properties. If the thickness of the insulating coating layer 227 is too small, it may easily detach from the current collector layer 225 or fail to provide adequate insulation, increasing the risk of internal short circuits in the bare cell 220 and reducing the safety performance of the energy storage device 200. Furthermore, if the thickness of the insulating coating layer 227 is too small, the difference between its thickness and the thickness of the active material layer 226 will be too large, easily leading to gray edge problems. During die-cutting, the equipment may not be able to effectively identify the two coatings, easily resulting in incorrect die-cutting specifications and increasing the difficulty of die-cutting.

[0092] In the terminology of this application, "gray cut" refers to the unexpected gray, dark, or rough marks on the edge of the die-cut product (usually the cut edge of a substrate such as paper or film), rather than a clean, clear, natural edge.

[0093] Preferably, the thickness h of the insulating coating layer 227 is in the range of 20μm≤h≤60μm.

[0094] In some embodiments, the peel strength T between the insulating coating layer 227 and the current collector layer 225 is in the range of 280 N / m ≤ T ≤ 340 N / m.

[0095] Specifically, the peel strength T between the insulating coating layer 227 and the current collector layer 225 can be, but is not limited to, 280 N / m, 282 N / m, 285 N / m, 290 N / m, 292 N / m, 295 N / m, 300 N / m, 305 N / m, 310 N / m, 315 N / m, 320 N / m, 325 N / m, 330 N / m, 332 N / m, 335 N / m, and 340 N / m.

[0096] In this embodiment, when the peel strength T between the insulating coating layer 227 and the current collector layer 225 meets the specified range, the insulating coating layer 227 and the current collector layer 225 have a high peel strength, making it difficult for the insulating coating layer 227 to detach from the current collector layer 225. This prevents short-circuit connections between the positive electrode 222 and the negative electrode 224, thus improving the safety performance of the energy storage device 200. When the peel strength T between the insulating coating layer 227 and the current collector layer 225 is too high, the interfacial bonding force between them is correspondingly too large. This strong bonding force may lead to poor leveling of the insulating coating material on the current collector layer 225 during the coating process of the insulating coating layer 227, easily resulting in local accumulation or edge pinholes. This requires additional adjustments to the coating pressure, speed, or slurry viscosity, increasing the difficulty of preparing the positive electrode 222 and thus making the preparation cost of the positive electrode 222 too high. When the peel strength T between the insulating coating layer 227 and the current collector layer 225 is too low, the insulating coating layer 227 is prone to peel off from the current collector layer 225, thereby increasing the probability of short circuit between the positive electrode 222 and the negative electrode 224, and ultimately making the safety performance of the energy storage device 200 poor.

[0097] Optionally, the energy storage device 200 further includes an electrolyte disposed within the receiving cavity 211 for wetting at least a portion of the bare battery cell 220.

[0098] Specifically, before the positive electrode 222 is immersed in the electrolyte, the peel strength between the insulating coating layer 227 and the current collector layer 225 is in the range of 280 N / m ≤ T ≤ 300 N / m.

[0099] Specifically, after the positive electrode 222 is immersed in the electrolyte, the peel strength between the insulating coating layer 227 and the current collector layer 225 is in the range of 300 N / m < T ≤ 340 N / m.

[0100] Optionally, the insulating coating layer 227 includes an insulating coating material, which includes ceramic particles, an adhesive, and a softener. The ceramic particles include, but are not limited to, boehmite particles. The adhesive includes, but is not limited to, polyvinylidene fluoride. The softener includes, but is not limited to, carboxylated nitrile rubber, natural rubber (NR), chloroprene rubber (CR), styrene-butadiene-styrene block copolymer, styrene-isoprene-styrene block copolymer, and methyl methacrylate-butadiene-styrene copolymer.

[0101] In this embodiment, the ceramic particles possess insulating properties, and the adhesive is used to bond the ceramic particles, thereby improving the adhesion between the insulating coating layer 227 and the current collector layer 225. Furthermore, the insulating coating material also includes a flexible agent, which is an elastic dispersion. When the flexible agent is applied to the insulating coating material, it acts as an elastomeric dispersion phase to absorb impact energy, significantly reducing the brittleness of the insulating coating material after curing. This facilitates the manufacturing and processing of the insulating coating layer 227 and prevents the insulating coating layer 227 from becoming too hard and brittle to detach directly from the current collector layer 225, thus resulting in high peel strength between the insulating coating layer 227 and the current collector layer 225. In addition, under high-temperature conditions, the insulating coating layer 227 and the current collector layer 225 also exhibit good adhesion, further enhancing the safety performance of the energy storage device 200.

[0102] Optionally, in some embodiments, in the insulating coating layer 227, the mass fraction of the ceramic particles ranges from 70% to 90%, the mass fraction of the adhesive ranges from 5% to 20%, and the mass fraction of the flexible agent ranges from 5% to 20%.

[0103] Specifically, the mass fraction of the ceramic particles can be, but is not limited to, 70%, 72%, 75%, 78%, 80%, 82%, 85%, 88%, and 90%. The mass fraction of the ceramic particles falls within a reasonable range to ensure that the insulating coating layer 227 has good insulation properties.

[0104] Specifically, the mass fraction of the adhesive can be, but is not limited to, 5%, 8%, 10%, 12%, 15%, 18%, 19%, and 20%. The mass fraction of the adhesive is within a reasonable range to ensure that the insulating coating layer 227 has good film-forming and processing properties. If the mass fraction of the adhesive is too low, the insulating coating layer 227 will be difficult to form a film and cannot effectively adhere to the current collector layer 225, which is detrimental to uniform coating; if the mass fraction of the adhesive is too high, the viscosity of the coating slurry will be too high, making coating and processing difficult.

[0105] Specifically, the mass fraction of the softening agent can be, but is not limited to, 5%, 8%, 10%, 12%, 15%, 18%, 19%, and 20%.

[0106] Optionally, after the energy storage device 200 is cyclically charged at 0.5P for 3 cycles at 25°C, a peel test is performed on the positive electrode 222 at room temperature, and the area of ​​peeling off the insulating coating 227 is less than 1 mm. 2 .

[0107] Optionally, after the energy storage device 200 is cycled at 0.5P for 3 times at 25°C, it is overcharged to 20V and disassembled. A peel test is then performed on the positive electrode 222. The area of ​​the insulating coating 227 that has detached is zero; in other words, the insulating coating 227 does not detach. The insulating coating 227 exhibits good adhesion properties under both normal and high temperature conditions, thereby improving the performance of the positive electrode 222 and the safety performance of the energy storage device 200.

[0108] Optionally, the insulating coating layer 227 is subjected to DSC (Differential Scanning Calorimetry) testing. The test results show that there is no exothermic peak below 200°C, and more preferably, there is no exothermic peak below 225°C. That is, the insulating coating layer 227 has good thermal stability. Even if the internal temperature of the energy storage device 200 is high, the insulating coating layer 227 still has good thermal stability, so that it can be disposed on the surface of the current collector layer 225 and firmly bonded to the current collector layer 225.

[0109] Optionally, the insulating coating layer 227 is subjected to FTIR (Fourier Transform Infrared Spectroscopy) testing, with the test structure being at 400 cm⁻¹. -1 Up to 1200cm -1 There are 7 distinct characteristic peaks within the wavenumber range, indicating that the insulating coating 227 includes the ceramic particles, the adhesive, and the flexible agent.

[0110] Please see Figure 12 and Figure 13 This application provides an electrical device 300, which includes: a device body 310 and an energy storage device 200 provided in this application, wherein the energy storage device 200 supplies power to the device body 310.

[0111] Understandably, the energy storage device 200 is electrically connected to the device body 310.

[0112] In this embodiment, the energy storage device 200 has high electrical connection stability and safety performance, and can provide stable power to the device body 310, so that the device body 310 can work stably and improve the user experience.

[0113] Optionally, the electrical device 300 in this embodiment can be, but is not limited to, portable electronic devices such as mobile phones, tablets, laptops, desktop computers, smart bracelets, smartwatches, e-readers, and game consoles. It can also be vehicles such as cars, trucks, sedans, vans, freight cars, bullet trains, high-speed trains, and electric bicycles. Furthermore, it can be various household appliances.

[0114] It is understood that the electrical device 300 described in this embodiment is merely one form of the electrical device 300 used by the battery, and should not be construed as a limitation on the electrical device 300 provided in this application, nor should it be construed as a limitation on the electrical device 300 provided in various embodiments of this application.

[0115] In this application, the terms "embodiment" and "implementation" mean that a specific feature, structure, or characteristic described in connection with an embodiment can be included in at least one embodiment of this application. The appearance of these phrases in various locations throughout the specification does not necessarily refer to the same embodiment, nor are they independent or alternative embodiments mutually exclusive with other embodiments. Those skilled in the art will understand, explicitly and implicitly, that the embodiments described in this application can be combined with other embodiments. Furthermore, it should be understood that the features, structures, or characteristics described in the various embodiments of this application can be arbitrarily combined to form another embodiment that does not depart from the spirit and scope of the technical solution of this application, provided there is no contradiction between them.

[0116] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application and are not intended to limit it. Although this application has been described in detail with reference to the above preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions to the technical solutions of this application should not depart from the spirit and scope of the technical solutions of this application.

Claims

1. An energy storage device (200), the energy storage device (200) comprising a housing (210), a bare battery cell (220), an adapter plate (230), and an end cap assembly (240), the housing (210) having a receiving cavity (211), the bare battery cell (220) and the adapter plate (230) being received within the receiving cavity (211), the end cap assembly (240) closing the receiving cavity (211), the adapter plate (230) being used to realize electrical connection between the bare battery cell (220) and the end cap assembly (240), characterized in that, The end cap assembly (240) includes a lower insulating member (241) and an end cap (242). The lower insulating member (241) is disposed on the side of the end cap (242) facing the bare battery cell (220). The lower insulating member (241) includes a body portion (2411) and a boss portion (2412). There are two boss portions (2412). The two boss portions (2412) are respectively connected to two ends of the body portion (2411) along a predetermined direction. The boss portion (2412) protrudes at least partially from the side of the body portion (2411) facing the bare battery cell (220). The bare battery cell (220) has a tab (221). The tab (221) is stacked and welded to the adapter piece (230). The tab (221) and the adapter piece (230) have a first solder mark area (250). Along a preset direction, the tab (221) has a first end (2211) near the boss (2412) and a second end (2212) away from the boss (2412), the distance between the first end (2211) and the first solder area (250) is less than the distance between the second end (2212) and the first solder area (250); wherein, the preset direction is the length direction of the energy storage device (200).

2. The energy storage device (200) according to claim 1, characterized in that, The tab (221) further includes a second solder area (270). The number of tabs (221) is multiple. The multiple tabs (221) are stacked and welded together to form the second solder area (270). The first solder area (250) is located within the second solder area (270).

3. The energy storage device (200) according to claim 2, characterized in that, The bare cell (220) includes a positive electrode (222), a separator (223), and a negative electrode (224). The positive electrode (222), the separator (223), and the negative electrode (224) are stacked and then wound. The positive electrode (222) includes a current collector layer (225), an active material layer (226), and an insulating coating layer (227). The active material layer (226) and the insulating coating layer (227) are disposed on the same side of the current collector layer (225). The current collector layer (225) includes a connected main body (2251) and a tab (221), and the tab (221) extends out of the main body (2251). On one side; the insulating coating layer (227) includes a first insulating part (2271) and a second insulating part (2272) connected together, the active material layer (226) and the first insulating part (2271) are connected and both are disposed on the main body part (2251); the second insulating part (2272) is disposed at one end of the tab (221) near the main body part (2251), the portion of the tab (221) without the second insulating part (2272) has the second solder area (270), and the portion of the tab (221) without the second insulating part (2272) is also used to weld with the adapter piece (230) to form the first solder area (250).

4. The energy storage device (200) according to claim 3, characterized in that, Along the arrangement direction of the main body (2251) and the tab (221), the first solder area (250) on the tab (221) is located at the end of the tab (221) away from the main body (2251).

5. The energy storage device (200) according to claim 3, characterized in that, The tab (221) has a preset bend line (228), which is located on the side of the second solder area (270) near the second insulating part (2272). The preset bend line (228) is offset from the second insulating part (2272).

6. The energy storage device (200) according to claim 3, characterized in that, Along the arrangement direction of the main body (2251) and the tab (221), the width d1 of the first insulating part (2271) is in the range of 0.5mm≤d1≤2.5mm.

7. The energy storage device (200) according to claim 3, characterized in that, Along the arrangement direction of the main body (2251) and the tab (221), the width d2 of the second insulating part (2272) ranges from 0.5mm to 12.5mm.

8. The energy storage device (200) according to claim 3, characterized in that, Along the thickness direction of the positive electrode sheet (222), the thickness of the insulating coating layer (227) is less than the thickness of the active material layer (226).

9. The energy storage device (200) according to claim 7, characterized in that, The thickness h of the insulating coating layer (227) is in the range of 10μm≤h≤150μm.

10. The energy storage device (200) according to claim 3, characterized in that, The peel strength T between the insulating coating layer (227) and the current collector layer (225) is in the range of 280 N / m ≤ T ≤ 340 N / m.

11. An electrical appliance (300), characterized in that, The electrical equipment (300) includes: Equipment body (310); and The energy storage device (200) according to any one of claims 1 to 10, wherein the energy storage device (200) supplies power to the device body (310).

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