Collecting plates, end cover assemblies, energy storage devices and electrical equipment

Abstract

The present application provides a current collecting plate, an end cover assembly, an energy storage device and an electrical device. The current collecting plate includes a first plate body and an extension portion. The extension portion is fixedly connected to the first plate body, and the extension portion and the first plate body are integrally formed.

Description

Technical Field

[0001] The present application relates to the technical field of energy storage devices, and in particular to a collecting plate, an end cover assembly, an energy storage device, and an electrical device. Background Art

[0002] Energy storage devices typically consist of an electrode assembly, a housing, and an end cap assembly. The electrode assembly is placed inside the housing, and the end cap assembly is mounted to the housing to achieve a seal. The end cap assembly is electrically connected to the electrode assembly via a current collector plate. In existing current collector plates, the plate and handle are often welded together. Summary of the Invention

[0003] The applicant has found that metal burrs or fine chips generated during welding of the disc body and the handle body can easily cut the tabs of the electrode assembly, or enter the interior of the electrode assembly and cause a short circuit, thereby reducing the reliability of the energy storage device.

[0004] The purpose of this application is to provide a current collecting plate, an end cover assembly, an energy storage device and an electrical equipment to solve the problem of welding the plate body and the handle body in the existing current collecting plate, which reduces the reliability of the energy storage device.

[0005] In a first aspect, an embodiment of the present application provides a current collecting plate, which includes a first plate body and an extension portion, wherein the extension portion is fixedly connected to the first plate body portion, and the extension portion and the first plate body portion are integrally formed.

[0006] In one embodiment, the first disk body portion includes a first surface, a second surface, and a peripheral surface, the first surface and the second surface are arranged opposite to each other along the thickness direction of the first disk body portion, the peripheral surface is connected between the first surface and the second surface, and the first disk body portion is provided with a notch, the notch is provided at the peripheral surface of the first disk body portion and passes through the first surface and the second surface, the notch results in the formation of a main wall surface and two side wall surfaces on the first disk body portion, the two side wall surfaces are connected to opposite sides of the main wall surface;

[0007] The extension portion is fixedly connected to the main wall surface and is spaced apart from the two side wall surfaces.

[0008] In one embodiment, the extension portion includes a bending section and a first extension section, the bending section is connected between the main wall surface and the first extension section, and the stress fatigue of the bending section is greater than the stress fatigue of the first disk portion and the first extension section;

[0009] The collecting tray has a folded state and an unfolded state. When the collecting tray is in the folded state, the extension portion is folded relative to the first tray body; when the collecting tray is in the unfolded state, the extension portion is unfolded relative to the first tray body, and the extension portion and the first tray body are in the same plane.

[0010] When the current collecting disc is in the folded state, the bent section is bent, and the first extension section is spaced apart from and arranged opposite to the first disc body; when the current collecting disc is in the unfolded state, the bent section is unfolded relative to the first disc body and the first extension section.

[0011] In one embodiment, the width dimension W of the bending section is greater than or equal to 1.5 mm and less than or equal to 3 mm.

[0012] In one embodiment, the second surface is provided with a plurality of first reinforcing ribs, the plurality of first reinforcing ribs are all located on the first disk portion adjacent to the notch and are spaced apart from each other, and all extend along the first disk portion toward the bending section;

[0013] The first extension section is provided with a plurality of second reinforcing ribs, which are located at one end of the first extension section facing the bending section and are spaced apart from each other and extend along the first extension section toward the bending section.

[0014] In one embodiment, multiple first reinforcing ribs are flush with the end surface of the bending section and are coplanar with the end surface of the bending section connected to the first disk body; multiple second reinforcing ribs are flush with the end surface of the bending section and are coplanar with the end surface of the bending section connected to the first extension section.

[0015] In one embodiment, the first extension section includes a first surface and a second surface, the first surface and the second surface are arranged opposite to each other along the thickness direction of the first extension section; the second reinforcing rib protrudes relative to the second surface;

[0016] When the current collecting plate is in the folded state, the first surface is arranged opposite to the first surface, and the second surface is arranged opposite to the second surface.

[0017] In one embodiment, the distance between two adjacent first reinforcing ribs gradually increases in a direction from the notch toward the center of the first disk body.

[0018] In one embodiment, the extension portion further includes a second extension segment, and the second extension segment is connected to an end of the first extension segment away from the bending segment;

[0019] When the current collecting plate is in the folded state, the portion of the second extending section facing the first extending section is bent, and the portion of the second extending section away from the first extending section is spaced apart from and opposite to the first extending section.

[0020] In one embodiment, a first welding groove is provided on the first surface of the first disc portion, and a bottom wall of the first welding groove is protruding relative to the second surface.

[0021] In one embodiment, the collecting plate further includes a second plate body portion, which is installed in the notch and overlaps with the first plate body portion; the second plate body portion is spaced apart from the extension portion.

[0022] In one embodiment, the second disk body portion includes a main body and two overlapping pieces, wherein the two overlapping pieces are disposed at opposite ends of the main body and both overlap with the first disk body portion;

[0023] The main body protrudes relative to the first disk body, and is provided with a second welding groove. When the collecting plate is in the expanded state, the main body is located on one side of the extension portion in the thickness direction and is spaced apart from the extension portion. The bottom wall of the second welding groove protrudes relative to the surface of the main body away from the extension portion.

[0024] In one embodiment, a distance D by which the main body protrudes from the first disc portion is greater than or equal to 0.2 mm and less than or equal to 0.8 mm.

[0025] In a second aspect, an embodiment of the present application provides an end cover assembly, comprising an end cover and the current collecting plate, wherein the current collecting plate is installed on one side of the end cover along the thickness direction.

[0026] In a third aspect, an embodiment of the present application provides an energy storage device, characterized in that it includes a shell, an electrode assembly and the end cover assembly, the shell has an opening, the shell is provided with a accommodating cavity, the electrode assembly is accommodated in the accommodating cavity, the end cover assembly is installed at the opening at one end of the shell, and the collecting plate is electrically connected to the electrode assembly.

[0027] In a fourth aspect, an embodiment of the present application provides an electrical device, characterized in that the electrical device includes the energy storage device, and the energy storage device supplies power to the electrical device.

[0028] This embodiment of the present application provides an integrally formed current collector plate, which avoids the impact of the welding process on the electrode assembly. The provision of a notch prevents the tabs from being pulled during the bending process, thereby improving the stability of the connection between the current collector plate and the tabs. Furthermore, this embodiment of the present application further expands the contact area between the current collector plate and the tabs by providing a second plate portion welded to the tabs, thereby improving the uniformity of the current collected by the current collector plate in the electrode assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0030] Figure 1 This is an application scenario diagram of the energy storage system provided in the embodiment of the present application;

[0031] Figure 2 A schematic structural diagram of the energy storage device provided in the first embodiment of the present application;

[0032] Figure 3 for Figure 2 A schematic structural diagram of an electrode assembly in the energy storage device shown;

[0033] Figure 4 for Figure 2 A schematic diagram of the exploded structure of the end cap assembly in the energy storage device shown;

[0034] Figure 5 for Figure 2 A cross-sectional structural diagram of the end cap assembly in the energy storage device shown;

[0035] Figure 6 for Figure 4 A schematic structural diagram of the first insulating component in the end cap assembly shown in another perspective;

[0036] Figure 7 for Figure 4 A schematic diagram of the structure of the collecting plate in the end cover assembly shown;

[0037] Figure 8 for Figure 7 A schematic diagram of the structure of the collecting plate when it is in an expanded state;

[0038] Figure 9 for Figure 8 The schematic diagram of the structure of the collecting plate shown in another perspective;

[0039] Figure 10 for Figure 2 A schematic diagram of a portion of the structure of the energy storage device during assembly is shown;

[0040] Figure 11 This is a structural schematic diagram of the current collecting plate of the second embodiment of the present application in an expanded state;

[0041] Figure 12 This is a schematic structural diagram of the second disk portion of the second embodiment of the present application;

[0042] Figure 13 for Figure 11 The cross-sectional structure diagram of the collecting plate along the AA direction is shown;

[0043] Figure 14 A schematic diagram of the partial structure of the energy storage device provided in the second embodiment of the present application in a partially bent state.

[0044] Reference numerals: energy storage system 1000; electric energy conversion device 600; user load 500; energy storage device 400; housing 100; end cap assembly 200; electrode assembly 300; mandrel area 310; negative electrode tab 330; end cap 10; fixing hole 12; pressure relief hole 14; mounting groove 15; explosion-proof valve 20; protective member 21; pole 30; column portion 31; carrier portion 33; first insulating component 40; insulating body 41; protrusion 42; through hole 44; conductive block 50; connecting hole 53; second insulating component 60; mounting hole 63; through hole 64; Collecting plate 80; sealing member 90; first plate body portion 81; through hole 811; notch 812; first welding groove 813; first surface 814; second surface 815; main wall surface 816; side wall surface 817; first reinforcing rib 818; extension portion 82; bending section 821; first extension section 822; second extension section 823; first surface 801; second surface 802; second reinforcing rib 824; second plate body portion 83; main body 830; third surface 831; fourth surface 832; lap joint 834; first section 835; second section 836; second welding groove 837. DETAILED DESCRIPTION

[0045] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0046] Because the energy we need is highly temporal and spatially dependent, rationally utilizing and improving energy efficiency requires a medium or device that can store one form of energy in the same form or convert it into another, allowing it to be released in a specific form based on future application needs. As we all know, achieving the goal of carbon neutrality currently relies primarily on developing green energy sources such as photovoltaics and wind power to replace fossil fuels.

[0047] Currently, the generation of green electricity generally relies on photovoltaics, wind power, and hydropower. However, wind and solar energy are generally intermittent and highly volatile, which can cause grid instability, insufficient electricity during peak hours, and excessive electricity during off-peak hours. Unstable voltage can also damage electricity. Therefore, insufficient electricity demand or insufficient grid capacity may lead to the problem of "wind and solar power curtailment". To solve these problems, we must rely on energy storage. That is, electrical energy is converted into other forms of energy through physical or chemical means and stored, and then converted into electrical energy and released when needed. Simply put, energy storage is like a large "power bank". When there is sufficient photovoltaic and wind energy, it stores electrical energy and releases the stored electricity when needed.

[0048] Taking electrochemical energy storage as an example, an embodiment of the present application provides an energy storage device 400, which has a group of chemical batteries inside. The energy storage device 400 mainly uses the chemical elements in the chemical batteries as energy storage media. The charging and discharging process is accompanied by chemical reactions or changes in the energy storage medium. Simply put, the electricity generated by wind energy and solar energy is stored in the chemical battery. When the use of external electricity reaches a peak, the stored electricity is released for use, or transferred to places where electricity is scarce for use.

[0049] Currently, energy storage (i.e., energy storage) has a wide range of application scenarios, including power generation-side energy storage, grid-side energy storage, renewable energy grid-connected energy storage, and user-side energy storage. The corresponding types of energy storage devices include:

[0050] (1) Large energy storage containers used in grid-side energy storage scenarios can serve as high-quality active and reactive power regulation power sources in the grid, achieving load matching of electricity in time and space, enhancing the ability to absorb renewable energy, and are of great significance in grid system backup, alleviating peak load power supply pressure, and peak and frequency regulation;

[0051] (2) The main operating mode of small and medium-sized energy storage cabinets used in industrial and commercial energy storage scenarios (banks, shopping malls, etc.) on the user side and small household energy storage boxes used in home energy storage scenarios on the user side is "peak shaving and valley filling". Since there is a large price difference in electricity prices at peak and valley locations according to electricity demand, after users have energy storage equipment, in order to reduce costs, they usually charge the energy storage cabinets / boxes during the low electricity price period; during the peak electricity price period, the electricity in the energy storage equipment is discharged for use to achieve the purpose of saving electricity bills. In addition, in remote areas and areas with high incidence of natural disasters such as earthquakes and hurricanes, the existence of household energy storage devices is equivalent to users providing themselves and the power grid with backup power, eliminating the inconvenience caused by frequent power outages due to disasters or other reasons.

[0052] See also Figure 1 , Figure 1 This is an application scenario diagram of the energy storage system 1000 provided in an embodiment of the present application.

[0053] like Figure 1 While the embodiments of this application illustrate household energy storage scenarios within user-side energy storage, it should be understood that the energy storage system 1000 provided herein is not limited to household energy storage scenarios. In this embodiment, the energy storage system 1000 can be a household energy storage system. The energy storage system 1000 includes an energy conversion device 600, a user load 500, and an energy storage device 400. The energy storage device 400 is a small energy storage box that can be mounted on an outdoor wall. For example, the energy conversion device 600 can be a photovoltaic panel. The energy conversion device 600 can convert solar energy into electricity during periods of low electricity prices. The energy storage device 400 stores this electricity and supplies it to user loads 500, such as streetlights and household appliances, during peak electricity prices, or during grid outages. In this embodiment, the energy storage device 400 can be, but is not limited to, a single cell, a battery module, a battery pack, or a battery system. For example, when the energy storage device 400 is a single cell, it can be either a cylindrical or a prismatic cell.

[0054] See also Figure 2 , Figure 2 This is a schematic structural diagram of the energy storage device 400 provided in the first embodiment of the present application.

[0055] In this embodiment, the energy storage device 400 is a cylindrical lithium-ion battery. The energy storage device 400 includes a housing 100, an electrode assembly ( Figure 2 The housing 100 is cylindrical and has two openings. The housing 100 defines a receiving cavity, with the openings located on either side of the cavity. The electrode assembly 300 is accommodated in the cavity. Along the height of the housing 100, the two end cap assemblies 200 are mounted on opposite sides of the openings and are electrically connected to the electrode assembly.

[0056] Specifically, the electrode assembly includes a positive electrode sheet, a negative electrode sheet, and a separator. The positive electrode sheet and the negative electrode sheet are spaced apart and arranged opposite to each other, and the separator is located between the positive electrode sheet and the negative electrode sheet. The tab of the positive electrode sheet is the positive electrode tab, and the tab of the negative electrode sheet is the negative electrode tab. The positive electrode tab and the negative electrode tab are arranged opposite to each other. Of the two end cap assemblies 200, one end cap assembly 200 is the end cap assembly on the negative electrode side, and the other end cap assembly 200 is the end cap assembly on the positive electrode side. The end cap assembly 200 on the negative electrode side is electrically connected to the negative electrode tab in the electrode assembly, and the end cap assembly 200 on the positive electrode side is electrically connected to the positive electrode tab in the electrode assembly, thereby achieving electrical connection between the two end cap assemblies 200 and the electrode assembly.

[0057] In the embodiment of the present application, the electrode assembly is placed in the housing 100, two end cap assemblies 200 are connected to the two ends of the electrode assembly, and the two end cap assemblies 200 are installed at opposite ends of the housing 100. Then, electrolyte is injected from the end cap assembly 200 on the positive electrode side to assemble the energy storage device 400. The electrode assembly is immersed in the electrolyte, and an electrochemical reaction can occur between the electrode assembly and the electrolyte, converting chemical energy into electrical energy, thereby enabling the energy storage device 400 to store electrical energy and output electrical energy.

[0058] See also Figure 3 , Figure 3 for Figure 2 A schematic structural diagram of the electrode assembly 300 in the energy storage device 400 is shown.

[0059] The electrode assembly 300 is roughly cylindrical and is formed by stacking a positive electrode sheet, a separator and a negative electrode sheet in sequence and then winding them. The electrode assembly 300 includes a core shaft area 310, which is a hollow area of ​​the electrode assembly 300 and is used to accommodate the electrolyte. The electrode assembly 300 may include a plurality of positive electrode tabs (not shown) and a plurality of negative electrode tabs 330, and the plurality of positive electrode tabs and the plurality of negative electrode tabs 330 are respectively located at opposite ends of the electrode assembly 300. The plurality of negative electrode tabs 330 are all arranged around the central axis of the electrode assembly 300 and are all in an inverted state. The contact area of ​​the negative electrode tab 330 in the inverted state is large, and it is easy to achieve electrical connection with the end cover assembly 200 on the negative electrode side. Electrical connection of the plurality of positive electrode tabs to the end cover assembly 200 on the positive electrode side.

[0060] In other embodiments, the number of the negative electrode tab 330 may also be one. The embodiment of the present application does not specifically limit the number of the positive electrode tab and the negative electrode tab 330 .

[0061] In the embodiment of the present application, the specific structure of the end cover assembly 200 is described by taking the end cover assembly 200 on the negative electrode side as an example.

[0062] See Figure 4 and Figure 5 , Figure 4 for Figure 2 The schematic diagram of the exploded structure of the end cover assembly 200 in the energy storage device 400 is shown. Figure 5 for Figure 2 A cross-sectional structural diagram of the end cover assembly 200 in the energy storage device 400 is shown.

[0063] For the convenience of description, define Figure 4 The height direction of the end cover assembly 200 is the Z-axis direction, the length direction of the extension portion 82 of the collecting plate 80 is the Y-axis direction, and the width direction of the extension portion 82 is the X-axis direction. The X-axis direction, the Y-axis direction and the Z-axis direction are perpendicular to each other.

[0064] The end cap assembly 200 includes an end cap 10, an explosion-proof valve 20, a protective member 21, a pole 30, a first insulating member 40, a conductive block 50, a second insulating member 60, a collecting plate 80, and a sealing member 90. The explosion-proof valve 20 is mounted on the end cap 10 to prevent the energy storage device 400 from exploding during use. The protective member 21 is mounted on the end cap 10 to protect the explosion-proof valve 20 from damage caused by the external environment and external forces. The second insulating member 60 is mounted on one side of the end cap 10 in the thickness direction (Z-axis direction). The conductive block 50 is located on the side of the end cap 10 facing away from the second insulating member 60. The first insulating member 40 is disposed between the end cap 10 and the conductive block 50 to insulate and separate the end cap 10 and the conductive block 50. The pole 30 passes through the second insulating member 60, the end cap 10, the first insulating member 40, and the conductive block 50 in sequence. The seal 90 is mounted on the pole 30 and is clamped between the pole 30 and the end cap 10 to insulate the pole 30 from the end cap 10. The current collecting plate 80 is connected to the side of the pole 30 facing away from the second insulating member 60. The current collecting plate 80 and the end cap 10 are isolated and insulated by the second insulating member 60.

[0065] Continue to see Figure 4 , the end cover 10 is provided with a fixing hole 12, a pressure relief hole 14 and a mounting groove 15. The fixing hole 12 and the pressure relief hole 14 both pass through the end cover 10 along the thickness direction (Z-axis direction) of the end cover 10. Among them, the fixing hole 12 is located in the middle of the end cover 10. In this embodiment, the fixing hole 12 is a circular hole. The pressure relief hole 14 is located on one side of the fixing hole 12 and is spaced apart from the fixing hole 12. The opening of the mounting groove 15 is located on the surface of the end cover 10 away from the second insulating part 60. The mounting groove 15 is recessed from the surface of the end cover 10 away from the second insulating part 60 to the surface facing the second insulating part 60. The mounting groove 15 is arranged around the fixing hole 12 and is connected to the fixing hole 12.

[0066] The explosion-proof valve 20 is mounted on the end cap 10 and covers the pressure relief hole 14 to block the pressure relief hole 14. The explosion-proof valve 20 covers the opening of the pressure relief hole 14 toward the collecting plate 80. The protective member 21 is mounted on the positive end cap 10 and covers the opening of the pressure relief hole 14 away from the collecting plate 80.

[0067] The second insulating component 60 is provided with a mounting hole 63 and a through-hole 64. Both the mounting hole 63 and the through-hole 64 extend through the second insulating component 60 along its thickness (Z-axis). Specifically, the mounting hole 63 is located in the middle of the second insulating component 60, opposite and connected to the fixing hole 12. The through-hole 64 is located to one side of the mounting hole 63 and spaced apart from the mounting hole 63. Furthermore, the through-hole 64 is located opposite the explosion-proof valve 20.

[0068] The conductive block 50 is provided with a connection hole 53 that extends through the conductive block 50 along its thickness (Z-axis). The first insulating component 40 is disposed between the end cap 10 and the conductive block 50. The first insulating component 40 is provided with a through hole 44. The through hole 44 is located in the middle of the first insulating component 40 and extends through the first insulating component 40 along its thickness (Z-axis) and connects the fixing hole 12 with the connection hole 53.

[0069] See also Figure 6 , Figure 6 for Figure 4 The structure diagram of the first insulating component 40 in the end cover assembly 200 is shown in another perspective.

[0070] The first insulating component 40 includes an insulating body 41 and a protrusion 42, and the protrusion 42 is fixedly connected to the insulating body 41. In this embodiment, the insulating body 41 and the protrusion 42 are integrally formed and are both made of insulating material. Specifically, the protrusion 42 is protruding from the surface of the insulating body 41 facing the end cover 10. The shape and size of the protrusion 42 are roughly the same as the shape and size of the mounting groove 15. Among them, along the thickness direction (Z-axis direction) of the first insulating component 40, the through hole 44 passes through the insulating body 41 and the protrusion 42.

[0071] See also Figure 5 The protrusion 42 of the first insulating component 40 is installed in the mounting groove 15 of the end cover 10 to increase the contact area between the first insulating component 40 and the end cover 10, increase the connection stability between the first insulating component 40 and the end cover 10, and thereby increase the assembly stability between the conductive voltage block 50 and the end cover 10.

[0072] The pole 30 is sequentially passed through the mounting hole 63 of the second insulating component 60, the fixing hole 12 of the end cover 10, the through hole 44 of the first insulating component 40 and the connecting hole 53 of the conductive voltage block 50. The pole 30 includes a columnar portion 31 and a seat portion 33. In this embodiment, along the height direction (Z-axis direction) of the pole 30, the seat portion 33 is connected to one end of the columnar portion 31. In this embodiment, the columnar portion 31 is roughly cylindrical. The seat portion 33 is roughly circular plate-shaped and protrudes relative to the peripheral side surface of the columnar portion 31. One end of the pole 30 is fixed to the connecting hole 53 and is exposed relative to the connecting hole 53. The seat portion 33 is supported on the surface of the second insulating component 60 facing away from the end cover 10.

[0073] Continue reading Figure 4The seal 90 is sleeved around the side surface of the cylindrical portion 31 of the terminal 30, penetrates the fixing hole 12 of the end cap 10, and is clamped between the terminal 30 and the wall of the fixing hole 12. This not only insulates the terminal 10 from the terminal 30, but also improves the installation seal between the terminal 10 and the terminal 30, thereby improving the sealing of the end cap assembly 200 after assembly. Exemplarily, the seal 90 is a sealing ring made of an insulating material such as plastic.

[0074] See also Figure 7 and Figure 8 , Figure 7 for Figure 4 The schematic structural diagram of the collecting plate 80 in the end cover assembly 200 is shown. Figure 8 for Figure 7 The structure diagram of the collecting plate 80 shown is in the expanded state. Figure 7 The collecting tray 80 is shown in a folded state. Figure 8 The dotted lines are only used to illustrate the areas of the collecting plate 80 and do not represent the actual structure.

[0075] The collecting plate 80 is fixedly connected to the surface of the supporting portion 33 of the pole 30 facing away from the second insulating component 60. The collecting plate 80 includes a first plate body portion 81 and an extension portion 82, and the extension portion 82 is fixedly connected to the first plate body portion 81. In the embodiment of the present application, the extension portion 82 and the first plate body portion 81 are integrally formed. Compared with the welded extension portion 82 and the first plate body portion 81 in the prior art, the integrally formed extension portion 82 and the first plate body portion 81 save a welding process, improve production efficiency, and avoid metal burrs or fine chips generated during the welding process from cutting the inverted pole lugs on the electrode assembly 300, or metal burrs or fine chips from entering the interior of the electrode assembly 300 and causing a short circuit.

[0076] In this embodiment, the collecting tray 80 has a folded state and an unfolded state. Figure 7 As shown, when the collecting plate 80 is in the folded state, the first plate body 81 and the extension portion 82 are folded relative to each other. Figure 8 As shown, when the collecting plate 80 is in the expanded state, the first plate body 81 and the extension portion 82 are relatively expanded, and the first plate body 81 and the extension portion 82 are flush with the same surface.

[0077] In this embodiment, the first disk body 81 is roughly disk-shaped. The first disk body 81 includes a first surface 814 and a second surface 815, and the first surface 814 is the surface of the first disk body 81 facing the second insulating component 60. Along the thickness direction (Z-axis direction) of the first disk body 81, the second surface 815 is arranged opposite to the first surface 814. The first disk body 81 is provided with a through hole 811 and a first welding groove 813. The through hole 811 is located in the middle of the first disk body 81 and passes through the first disk body 81 along the thickness direction (Z-axis direction) of the first disk body 81. Among them, the through hole 811 and the core shaft area 310 of the electrode assembly 300 (such as Figure 3 The first welding groove 813 is located on one side of the through hole 811 and is spaced apart from the through hole 811. The opening of the first welding groove 813 is located on the first surface 814, and the first welding groove 813 is recessed from the first surface 814 toward the second surface 815. The bottom wall of the first welding groove 813 protrudes relative to the second surface 815 and is used to connect with the electrode tab (as shown in FIG. Figure 3 811) to achieve electrical connection between the current collecting plate 80 and the electrode assembly 300, thereby achieving electrical connection between the end cap assembly 200 and the electrode assembly 300. There are two first welding grooves 813, which are located on opposite sides of the through hole 811 and are spaced apart from the through hole 811. Exemplarily, the first welding grooves 813 are formed by a stamping process.

[0078] The first plate portion 81 also has a notch 812, which is located on one side of the through-hole 811 and between the two first welding grooves 813. The notch 812 is spaced apart from both the through-hole 811 and the two first welding grooves 813. The notch 812 is provided on the circumference of the first plate portion 81 and extends through the first plate portion 81 along its thickness (Z-axis). The notch 812 forms a main wall 816 and two opposing side walls 817 on the first plate portion 81. The main wall 816 is connected to the two side walls 817.

[0079] Please also refer to Figure 8 and Figure 9 , Figure 9 for Figure 8 The structure diagram of the collecting plate 80 shown is from another perspective.

[0080] The first disk body 81 is also provided with a plurality of first reinforcing ribs 818. The plurality of first reinforcing ribs 818 are located on the side of the through hole 811 facing the notch 812 (in the Y-axis direction), and are located between the two first welding grooves 813. The plurality of first reinforcing ribs 818 are spaced apart from the notch 812 and the two first welding grooves 813. The plurality of first reinforcing ribs 818 are arranged at intervals from each other. The plurality of first reinforcing ribs 818 not only enhance the strength of the first disk body 81 in the thickness direction (in the Z-axis direction), but also abut against the fallen tabs to prevent the tabs from warping. At the same time, they can increase the contact area between the first disk body 81 and the tabs, thereby improving the current collecting effect of the current collecting disk 80.

[0081] In this embodiment, the end faces of the plurality of first reinforcing ribs 818 facing the notch 812 (Y-axis direction) are flush and coplanar with the main wall surface 816 of the notch 812 (a certain error is allowed). The plurality of first reinforcing ribs 818 generally extend in the direction along the notch 812 toward the through hole 811. Exemplarily, the first reinforcing ribs 818 are formed by a stamping process, and the first reinforcing ribs 818 are recessed from the first surface 814 toward the second surface 815. In addition, the plurality of first reinforcing ribs 818 are distributed radially, and the distance between two adjacent first reinforcing ribs 818 gradually increases along the direction from the notch 812 toward the through hole 811. The radial distribution of the plurality of first reinforcing ribs 818 can not only further increase the contact area between the first disk portion 81 and the tab, thereby improving the current collection effect, but also increase the number of tabs abutted by the plurality of first reinforcing ribs 818, thereby improving the abutment effect and preventing the tabs from warping.

[0082] The extension portion 82 is fixedly connected to the main wall surface 816 of the notch 812 and is spaced apart from both side walls 817. The extension portion 82 includes a bent section 821, a first extension section 822, and a second extension section 823. The bent section 821 is fixedly connected to the main wall surface 816 of the notch 812 and is spaced apart from both side walls 817. The width dimension W of the bent section 821 is greater than or equal to 1.5 mm and less than or equal to 3 mm. The first extension section 822 is connected between the bent section 821 and the second extension section 823. When the collecting plate 80 is in the expanded state, the extension portion 82 is in the shape of an elongated strip, and the bent section 821, the first extension section 822, and the second extension section 823 are basically in the same plane.

[0083] The first extension section 822 is connected to the end of the bent section 821 facing away from the first disc portion 81. The first extension section 822 includes a first surface 801 and a second surface 802. When the collecting disc 80 is in the expanded state, the first surface 801 is flush with the first surface 814. Along the thickness direction (Z-axis) of the first extension section 822, the second surface 802 is disposed opposite the first surface 801. The first extension section 822 is provided with a plurality of second reinforcing ribs 824. These ribs are located at the end of the first extension section 822 facing the bent section 821 and are spaced apart along the width direction (X-axis) of the first extension section 822. The plurality of second reinforcing ribs 824 extend along the length direction (Y-axis) of the first extension section 822. The plurality of second reinforcing ribs 824 enhance the strength of the first extension section 822 in the thickness direction (Z-axis). Exemplary second reinforcing ribs 824 are formed by stamping. The second reinforcing ribs 824 are recessed from the first surface 801 toward the second surface 802.

[0084] See also Figure 7 In the energy storage device 400, the current collecting disk 80 is in a folded state, the bending section 821 is bent, and along the thickness direction (Z-axis direction) of the first extension section 822, the first extension section 822 is spaced apart from and opposite to the first disk body 81, the second extension section 823 is bent toward the first extension section 822, and the second extension section 823 is spaced apart from and opposite to the first extension section 822. At this time, the second reinforcing rib 824 protrudes relative to the second surface 802. When the energy storage device 400 falls, the electrolyte in the core shaft area 310 will pass through the through hole 811 and impact the first extension section 822. When the electrolyte impacts the second surface 802, the electrolyte can flow back to the electrode assembly 300 along the channel between the adjacent second reinforcing ribs 824, and will not stay on the second surface 802 to cause waste.

[0085] In the embodiment of the present application, the end surfaces of the plurality of second reinforcing ribs 824 facing the first plate portion 81 are flush and coplanar with the end surface of the bent section 821 connecting to the first extension section 822 (a certain error is allowed). It is understood that the plurality of second reinforcing ribs 824 and the plurality of first reinforcing ribs 818 together define the bent section 821, and the distance between the end surfaces of the plurality of second reinforcing ribs 824 facing the first plate portion 81 and the surfaces of the plurality of first reinforcing ribs 818 facing the notch 812 is the width W of the bent section 821.

[0086] Please also refer to Figure 7 and Figure 10 , Figure 10 for Figure 2 FIG. 4 is a schematic diagram of a portion of the structure of the energy storage device 400 during the assembly process.

[0087] During the assembly of the energy storage device 400, after the electrode assembly 300 is installed on the inner side of the shell 100, the assembled end cap assembly 200 is connected to one end of the electrode assembly 300. Specifically, the second extension section 823 of the current collecting disc 80 in the unfolded state is first welded to the pole 30, and then the bottom wall of the first welding groove 813 is welded to the pole tab of the electrode assembly 300 to achieve electrical connection between the end cap assembly 200 and the electrode assembly 300. At this time, the multiple first reinforcing ribs 818 of the first disc body 81 abut against the multiple pole tabs, and the through hole 811 of the current collecting disc 80 is arranged relative to the core shaft area 310 of the electrode assembly 300. Then, the current collecting disc 80 is bent until it is in a folded state.

[0088] like Figure 10 As shown, in the embodiment of the present application, because the stress fatigue of the bending section 821 is significantly higher than that of the first disk portion 81 provided with the first reinforcing rib 818 and the first extension section 822 provided with the second reinforcing rib 824, when the extension section 82 bends relative to the first disk portion 81, the fold between the extension section 82 and the first disk portion 81 is necessarily located within the bending section 821 where the stress fatigue is higher, and the distribution range of the fold is relatively fixed. Because the width dimension W of the bending section 821 is greater than or equal to 1.5 mm, it can ensure that the first reinforcing rib 818 and the second reinforcing rib 824 will not contact or squeeze each other when the extension section 82 bends relative to the first disk portion 81, thereby preventing the folding of the collecting tray 80 from being affected. Moreover, the width dimension W is less than or equal to 3 mm, which can ensure that the bending section 821 is narrow enough, so that the distribution range of the fold between the extension portion 82 and the first disk body portion 81 is sufficiently determined, ensuring that the actual bending direction of the extension portion 82 is consistent with the preset bending direction, thereby improving the consistency of the bending direction of the collecting plate 80 during the assembly process, and thereby improving the consistency of different energy storage devices 400 when leaving the factory; at the same time, the bending stress generated by the first bending of the extension portion 82 is also roughly concentrated in the bending section 821, and will not cause the first welding groove 813 set at a distance from the bending section 821 to warp upward, reducing the possibility of the first welding groove 813 pulling the pole ear welded to it, improving the stability of the connection between the collecting plate 80 and the pole ear, and ensuring the welding stability and flow effect of the collecting plate 80 and the pole ear.

[0089] Please also refer to Figures 11 to 13 , Figure 11 This is a structural diagram of the current collecting plate 80 of the second embodiment of the present application in an expanded state. Figure 12 This is a schematic structural diagram of the second disk portion 83 of the second embodiment of the present application. Figure 13 for Figure 11 The cross-sectional structural view of the collecting plate 80 along the AA direction is shown.

[0090] like Figure 11As shown, the energy storage device 400 of the second embodiment has the same structure as the energy storage device 400 of the first embodiment, except that the current collecting disk 80 of the energy storage device 400 of the second embodiment further includes a second disk portion 83. The second disk portion 83 is installed in the notch 812 of the first disk portion 81, and can form a substantially complete circular disk together with the first disk portion 81. The second disk portion 83 is spaced apart from the extension portion 82.

[0091] like Figure 12 As shown, the second disk portion 83 includes a main body 830 and two lap joints 834, and the two lap joints 834 are arranged at opposite ends of the main body 830. The main body 830 is in the shape of a thin plate, and the main body 830 includes a third surface 831 and a fourth surface 832. The third surface 831 is oriented in the same direction as the first surface 814, and is arranged opposite to the fourth surface 832 along the thickness direction (Z-axis direction) of the main body 830. The main body 830 is provided with a second welding groove 837. The opening of the second welding groove 837 is located on the third surface 831, and the second welding groove 837 is recessed from the third surface 831 toward the fourth surface 832. The bottom wall of the second welding groove 837 protrudes relative to the fourth surface 832, and is used to mate with the pole ear (such as Figure 3 As shown) is electrically connected to realize electrical connection between the current collecting plate 80 and the electrode assembly 300, thereby realizing electrical connection between the end cover assembly 200 and the electrode assembly. Exemplarily, the second welding groove 837 is formed by a stamping process. The lap joint 834 is roughly L-shaped, including a first section 835 and a second section 836. The first section 835 is protruding from the third surface 831 of the main body 830, and the second section 836 is connected to the end of the first section 835 away from the third surface 831, and the first section 835 and the second section 836 are arranged at an angle. The first sections 835 of the two lap joints 834 extend in the same direction (Z-axis direction), and the second sections 836 of the two lap joints 834 extend in opposite directions (X-axis direction).

[0092] Continue reading Figure 11 The second plate portion 83 overlaps the first plate portion 81 via two bridging members 834. The first section 835 of the bridging member 834 is positioned opposite the sidewall of the notch 812, while the second section 836, facing the third surface 831, overlaps the first surface 814 of the first plate portion 81. The main body 830 of the second plate portion 83 is located on the side of the first extension 822 facing away from the first surface 801. The main body 830 and the extension 82 are positioned opposite and spaced apart in the thickness direction (Z-axis) of the current collecting plate 80. Furthermore, the bridging member 834 is spaced apart from the extension 82 in the width direction (X-axis) of the extension 82.

[0093] Please refer to Figure 13At this time, the distance D that the body 830 protrudes from the first disk portion 81 is greater than or equal to 0.2 mm and less than or equal to 0.8 mm. The distance D refers to the distance between the fourth surface 832 of the second disk portion 83 and the second surface 815 of the first disk portion 81. The body 830 protruding relative to the first disk portion 81 can limit the movement space of the negative electrode tab 330 located at the notch 812 in the height direction (Z-axis direction) of the electrode assembly 300, preventing the negative electrode tab 330 corresponding to the notch 812 from warping, or even turning outward and overlapping the inner wall of the housing 100 through the notch 812 to form a short circuit.

[0094] During the assembly of the energy storage device 400, after the bottom wall of the first welding slot 813 of the first disc portion 81 is welded to the tab of the electrode assembly 300, the second disc portion 83 is installed in the notch 812 of the first disc portion 81. The second disc portion 83 is overlapped with the first disc portion 81 via two lap joints 834. The bottom wall of the second welding slot 837 is then welded to the tab corresponding to the notch 812, thereby securing the second disc portion 83 to the tab. The overlapped connection forms an electrical connection between the second disc portion 83 and the first disc portion 81. The provision of the second disc portion 83 increases the contact area between the current collecting disc 80 and the tab, improving the current collection effect, increasing the uniformity of the current collected by the current collecting disc 80 from the electrode assembly 300, and improving the consistency of the production of different energy storage devices 400.

[0095] See Figure 14 , Figure 14 This is a schematic diagram of the partial structure of the energy storage device 400 provided in the second embodiment of the present application in a partially bent state.

[0096] In the embodiment of the present application, when the extension portion 82 is bent relative to the first plate portion 81, since the second plate portion 83 is only overlapped with the first plate portion 81 via the lap joint 834, the bending stress near the bent section 821 will not affect the second plate portion 83, and will not cause the second welding groove 837 to warp upward, thereby reducing the possibility that the second welding groove 837 will pull on the negative electrode tab 330 located at the notch 812. Therefore, the solution of welding the second plate portion 83 to the tab and the first plate portion 81 to the tab adopted in the present application improves the stability of the connection between the second plate portion 83 and the tab, thereby ensuring the welding effect and flow rate of the current collecting plate 80 and the tab.

[0097] The present embodiment provides an integrally formed current collecting plate 80, which avoids the impact of the welding process on the electrode assembly 300. Furthermore, by providing a first reinforcing rib 818 and a second reinforcing rib 824 to define a bending section 821, the bending stress of the current collecting plate during bending is concentrated in the bending section 821, preventing the first welding groove 813 from pulling on the electrode tab, thereby improving the connection stability between the current collecting plate 80 and the tab. Furthermore, by providing a second plate portion 83 welded to the tab, the present embodiment further expands the contact area between the current collecting plate 80 and the tab, thereby improving the uniformity of the current collected by the current collecting plate 80 in the electrode assembly 300.

[0098] The above disclosure is only a preferred embodiment of the present application, and it is certainly not intended to limit the scope of the rights of the present application. A person skilled in the art can understand that all or part of the processes of the above embodiments and equivalent changes made in accordance with the claims of the present application are still within the scope of the present application.

Claims

1. A collecting plate (80), characterized in that: The collecting plate (80) comprises a first plate body portion (81) and an extension portion (82), wherein the extension portion (82) is fixedly connected to the first plate body portion (81), and the extension portion (82) and the first plate body portion (81) are integrally formed; The first disk body (81) includes a peripheral surface, the first disk body (81) is provided with a notch (812), the notch (812) is provided at the peripheral surface of the first disk body (81) and passes through the first disk body (81), the first disk body (81) includes a first surface (814) and a second surface (815), the first surface (814) and the second surface (815) are arranged opposite to each other along the thickness direction of the first disk body (81), the notch (812) passes through the first surface (814) and the second surface (815), the notch (812) causes a main wall surface (816) and two side wall surfaces (817) to be formed on the first disk body (81), and the two side wall surfaces (817) are connected to opposite sides of the main wall surface (816); The collecting disc (80) further includes a second disc body (83), the second disc body (83) being used for connecting to the tab, the second disc body (83) being installed in the notch (812) and overlapping the first disc body (81).

2. The collecting plate (80) according to claim 1, characterized in that: The peripheral surface is connected between the first surface (814) and the second surface (815); The extension portion (82) is fixedly connected to the main wall surface (816) and is spaced apart from the two side wall surfaces (817).

3. The collecting plate (80) according to claim 2, characterized in that: The extension portion (82) comprises a bending section (821) and a first extension section (822); the bending section (821) is connected between the main wall surface (816) and the first extension section (822); and the stress fatigue of the bending section (821) is greater than the stress fatigue of the first disc portion (81) and the first extension section (822); The collecting disc (80) has a folded state and an unfolded state. When the collecting disc (80) is in the folded state, the extension portion (82) is folded relative to the first disc body portion (81), the bending section (821) is bent, and the first extension section (822) is spaced apart from and arranged relative to the first disc body portion (81); when the collecting disc (80) is in the unfolded state, the extension portion (82) is unfolded relative to the first disc body portion (81) and the first extension section (822), and the extension portion (82) and the first disc body portion (81) are in the same plane.

4. The collecting plate (80) according to claim 3, characterized in that The width dimension W of the bending section (821) is greater than or equal to 1.5 mm and less than or equal to 3 mm.

5. The collecting plate (80) according to claim 3, characterized in that: The second surface (815) is provided with a plurality of first reinforcing ribs (818), the plurality of first reinforcing ribs (818) are all located at the first disk body portion (81) adjacent to the notch (812) and are spaced apart from each other, and all extend along the first disk body portion (81) toward the bending section (821); The first extension section (822) is provided with a plurality of second reinforcing ribs (824), the plurality of second reinforcing ribs (824) being located at one end of the first extension section (822) facing the bending section (821) and spaced apart from each other, and all extending in a direction from the first extension section (822) to the bending section (821).

6. The collecting plate (80) according to claim 5, characterized in that: The plurality of first reinforcing ribs (818) are flush with the end surface of the bending section (821) and are coplanar with the end surface of the bending section (821) connected to the first disk portion (81); the plurality of second reinforcing ribs (824) are flush with the end surface of the bending section (821) and are coplanar with the end surface of the bending section (821) connected to the first extension section (822).

7. The collecting plate (80) according to claim 5, characterized in that: The first extension section (822) comprises a first surface (801) and a second surface (802), the first surface (801) and the second surface (802) being arranged opposite to each other along the thickness direction of the first extension section (822); the second reinforcing rib (824) protrudes relative to the second surface (802); When the collecting plate (80) is in the folded state, the first surface (801) and the first surface (814) are arranged opposite to each other, and the second surface (802) and the second surface (815) are arranged opposite to each other.

8. The collecting plate (80) according to claim 5, characterized in that: Along the direction from the notch (812) to the center of the first disk body (81), the distance between two adjacent first reinforcing ribs (818) gradually increases.

9. The collecting plate (80) according to any one of claims 3 to 8, characterized in that: The extension portion (82) further includes a second extension section (823), wherein the second extension section (823) is connected to an end of the first extension section (822) away from the bending section (821); When the collecting plate (80) is in the folded state, the portion of the second extension section (823) that is directed toward the first extension section (822) is bent, and the portion of the second extension section (823) that is away from the first extension section (822) is spaced apart from and arranged relative to the first extension section (822).

10. The collecting plate (80) according to claim 2, characterized in that: A first welding groove (813) is provided on the first surface (814) of the first disc body (81), and a bottom wall of the first welding groove (813) protrudes relative to the second surface (815).

11. The collecting plate (80) according to claim 3, characterized in that: The second disc portion (83) and the extension portion (82) are spaced apart.

12. The collecting plate (80) according to claim 11, characterized in that The second disk body portion (83) includes a main body (830) and two overlapping pieces (834), wherein the two overlapping pieces (834) are arranged at opposite ends of the main body (830) and are both overlapped with the first disk body portion (81); The main body (830) protrudes relative to the first disc portion (81), and the main body (830) is provided with a second welding groove (837). When the collecting disc (80) is in the expanded state, the main body (830) is located on one side of the extension portion (82) in the thickness direction and is spaced apart from the extension portion (82). The bottom wall of the second welding groove (837) protrudes relative to the surface of the main body (830) away from the extension portion (82).

13. The collecting plate (80) according to claim 12, characterized in that The distance D that the main body (830) protrudes from the first disc portion (81) is greater than or equal to 0.2 mm and less than or equal to 0.8 mm.

14. An end cap assembly (200), characterized in that: It comprises an end cover (10) and a current collecting plate (80) according to any one of claims 1 to 13, wherein the current collecting plate (80) is mounted on one side of the end cover (10) along a thickness direction.

15. An energy storage device (400), characterized in that The invention comprises a shell (100), an electrode assembly (300), and an end cap assembly (200) according to claim 14, wherein the shell (100) has an opening, the shell (100) is provided with an accommodating cavity, the electrode assembly (300) is accommodated in the accommodating cavity, the end cap assembly (200) is mounted at the opening at one end of the shell (100), and the current collecting plate (80) is electrically connected to the electrode assembly (300).

16. An electrical device, characterized in that: The electric device comprises the energy storage device (400) according to claim 15, and the energy storage device (400) supplies power to the electric device.

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