Current collector plate, battery cell, and electric device

Abstract

The application provides a current collecting plate, a battery monomer and an electric device. The current collecting plate comprises: a plurality of stress dispersion parts arranged at intervals in the circumferential direction and an outer ring fixing part connected between adjacent stress dispersion parts; the stress dispersion part comprises: a fixing pin, a stress connecting part and an electrode pin arranged in sequence from the radial outer side to the radial inner side, the outer ring fixing part is connected to the stress connecting part, and the electrode pin extends towards the radial inner side, wherein the fixing pin is used for fixed connection with a shell assembly of the battery monomer, the electrode pin is used for welding with an electrode assembly of the battery monomer, and a through groove is formed between the edges of the electrode pin. The above technical scheme can at least help to disperse stress and reduce the deformation of the disc surface area of the current collecting plate.

Description

Technical Field

[0001] This application relates to the field of battery technology, and more specifically, to a current collector, a battery cell, and an electrical device. Background Technology

[0002] In the field of new energy power batteries, a single battery cell generally includes an electrode assembly located within a housing assembly. The electrode assembly comprises a positive electrode, a negative electrode, and a separator located between the positive and negative electrode sheets. These positive and negative electrode sheets and the separator are stacked and wound to form the electrode assembly, which is then encapsulated within the housing assembly. The electrode assembly's tabs are electrically connected to the housing assembly via current collectors. However, existing current collectors are susceptible to stress, leading to deformation of the collector surface area. Utility Model Content

[0003] In view of the problems existing in the related technologies, the purpose of this application is to provide a current collector, a battery cell and an electrical device, which can at least help to disperse stress and reduce the deformation of the current collector surface area.

[0004] To achieve the above objectives, this application provides a current collector for a battery cell, comprising: a plurality of stress-dispersing portions spaced circumferentially and an outer ring fixing portion connected between adjacent stress-dispersing portions; the stress-dispersing portion includes: a fixing pin, a stress-connecting portion, and an electrode pin sequentially connected from the radially outer side to the radially inner side, the outer ring fixing portion being connected to the stress-connecting portion, and the electrode pin extending radially inner, wherein the fixing pin is used for fixed connection with the housing assembly of the battery cell, the electrode pin is used for electrical connection with the electrode assembly of the battery cell, and a through groove is formed between the edges of the electrode pin.

[0005] In some embodiments, the through slot includes a central hole and a gap portion that communicates with the central hole and extends radially; the electrode pin includes two side edges disposed opposite each other in the circumferential direction and an inner edge located radially inward; the side edges are straight edges extending radially, and a gap portion is formed between the side edges; the inner edge is an arc-shaped edge, and the arc-shaped edge surrounds the central hole to form a circular hole.

[0006] In some embodiments, the stress connection includes a first connection portion connected to an electrode pin, a second connection portion connected to a fixed pin, and a transition portion between the first connection portion and the second connection portion, wherein the circumferential width of the first connection portion and the second connection portion is smaller than the circumferential width of the transition portion.

[0007] In some embodiments, the gap extends radially and covers the side edge of the electrode pin and the side edge of the first connection portion, and the circumferential width of the first connection portion is greater than the circumferential width of the corresponding electrode pin.

[0008] In some embodiments, the stress dispersion section further includes a stress absorption section, which is disposed at the connection between the second connection section and the transition section, and the thickness of the collector plate at the stress absorption section is less than the thickness at the second connection section or the transition section.

[0009] In some embodiments, the gap includes a first gap located between the side edges of two adjacent electrode pins and a second gap located on opposite sides of the first connection in the circumferential direction, the second gap extending circumferentially; the fixed pin is bent relative to the second connection and extends in an arc shape in the circumferential direction.

[0010] In some embodiments, the stress dispersion portion further includes: an edge groove formed at the connection between the second connecting portion and the transition portion, the edge groove extending inward from the outer edge of the connection portion, two edge grooves corresponding to each stress dispersion portion being radially symmetrical and arranged at an included angle, wherein the distance between the two edge grooves gradually decreases in the direction from the radially outer side to the radially inner side. In some embodiments, the stress dispersion portion further includes a root groove extending radially and disposed in the stress connection portion, and a portion of the root groove is distributed on the electrode pin; each stress dispersion portion has at least two root grooves, the at least two root grooves being circumferentially spaced apart.

[0011] Embodiments of this application also provide a battery cell, including: a housing assembly defining a receiving cavity; an electrode assembly disposed within the receiving cavity, one end of the electrode assembly having a tab; and the aforementioned current collector, the current collector being located between the tab of the electrode assembly and the housing assembly, the electrode pins being electrically connected to the tabs, the fixed pins being fixedly connected to the housing assembly, the through groove including a central hole and a gap portion extending radially through the central hole, a portion of the gap portion being formed radially outside the electrode pins, the central hole and the central axial hole of the electrode assembly being correspondingly arranged axially in the electrode assembly, and the portion of the gap portion being arranged closer to the outer peripheral surface of the electrode assembly than the central axial hole of the electrode assembly.

[0012] In some embodiments, the electrode pins are welded to the tabs, and the electrode pins have a first solder mark formed by welding. The first solder mark is distributed on the electrode pins and the stress connection portion. The fixed pins are welded to the housing assembly, and the fixed pins have a second solder mark formed by welding. The second solder mark is distributed circumferentially.

[0013] Embodiments of this application also provide an electrical device that includes the aforementioned battery cell.

[0014] The beneficial effects of this application include:

[0015] The outer ring fixing part is connected to the stress connection part, and the outer ring fixing part is connected to several stress dispersion parts arranged at intervals in the circumferential direction. This can isolate the stress transmission between each stress dispersion part, play the role of circumferential stress absorption and dispersion, which helps to reduce the deformation of the disk area and avoid stress concentration that could damage the electrical connection between the electrode pin and the electrode assembly or cause the fixing pin to break and fail. Attached Figure Description

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

[0017] Figure 1 A perspective view of a battery cell according to some embodiments is shown.

[0018] Figure 2 A schematic cross-sectional view of a vertical section of a battery cell according to an embodiment of this application is shown.

[0019] Figure 3 , Figure 4 , Figure 5 , Figure 6 and Figure 7 Plan view diagrams of the manifold according to different embodiments of this application are shown.

[0020] Figure 8 A schematic diagram is shown when the electronic device according to an embodiment of this application is a vehicle. Detailed Implementation

[0021] To better understand the spirit of the embodiments of this application, the following description is based on some preferred embodiments of this application.

[0022] Embodiments of this application will be described in detail below. Throughout this specification, identical or similar components and components having identical or similar functions are indicated by similar reference numerals. The embodiments described herein with reference to the accompanying drawings are illustrative and diagrammatic in nature and are intended to provide a basic understanding of this application. The embodiments of this application should not be construed as limiting this application.

[0023] As used herein, the terms “approximately,” “generally,” “substantially,” and “about” are used to describe and indicate minor variations. When used in conjunction with an event or situation, the terms may refer to examples in which the event or situation occurred precisely or in examples in which the event or situation occurred very approximately.

[0024] In this specification, unless otherwise specified or limited, relative terms such as “central,” “longitudinal,” “lateral,” “front,” “rear,” “right,” “left,” “inner,” “outer,” “lower,” “higher,” “horizontal,” “vertical,” “above,” “below,” “above,” “below,” “top,” “bottom,” and their derivatives (e.g., “horizontally,” “downward,” “upward,” etc.) should be interpreted as referring to the directions described in the discussion or depicted in the accompanying drawings. These relative terms are used for descriptive convenience only and do not require that this application be constructed or operated in a particular orientation.

[0025] For ease of description, "first," "second," "third," etc., can be used in this article to distinguish different components of a figure or a series of figures. "First," "second," "third," etc., are not intended to describe the corresponding components.

[0026] During battery manufacturing, deformation stress caused by processes such as welding, grooving, and sealing is transmitted to the surface area of ​​the current collector, causing deformation such as wrinkling or warping, reducing the flatness of the current collector. Furthermore, the fixed pins of the current collector are fixedly connected to the battery casing, for example, by welding to form a casing welding area, and the surface is electrically connected to the electrode assembly, for example, by spaced-apart electrode welding areas on the surface. Deformation of the surface area can damage the electrical connection with the electrode assembly (e.g., tearing of the solder joints in the electrode welding area) or cause excessive deformation and breakage of the fixed pins. Additionally, these two welding areas affect the current transmission path; if the welding areas are too scattered, it increases the current flow path, which is detrimental to controlling the cell's DCR (DC resistance). To address at least the above problems, this application provides a current collector, a battery cell, and an electrical device.

[0027] Figure 1 A perspective view of a battery cell 100 according to some embodiments is shown. Figure 2 A schematic cross-sectional view of a vertical section of a battery cell 100 according to an embodiment of this application is shown.

[0028] Combination Figures 1 to 2 As shown in this embodiment, the battery cell 100 is illustrated as a cylindrical battery for example. However, this application is not limited to cylindrical battery types; it can also be other battery types such as prismatic batteries with rigid housing assemblies and explosion-proof valves. In some embodiments, the battery cell 100 can be a 4680 cylindrical battery (46mm in diameter, 80mm in height), a 4695 cylindrical battery (46mm in diameter, 95mm in height), or a 46120 cylindrical battery (46mm in diameter, 120mm in height). Here, the diameter refers to the outer diameter of the housing.

[0029] The battery cell 100 includes a housing assembly, which includes a housing 200 and an end cap 220. The housing 200 may specifically include an end wall 111 and a side wall 109 surrounding the end wall 111. As long as a stable sealing and electrical connection can be formed, the connection between the end wall 111 and the side wall 109 can be achieved in various ways, such as integral stamping, integral casting, or separate welding. The side wall 109 can be cylindrical or follow any other closed-loop contour that matches the end wall 111. In this embodiment, the outer edge of the end wall 111 is circular, and the side wall 109 is cylindrical and surrounds the outer edge of the end wall 111. An opening 205 is formed at the end of the side wall 109 opposite to the end wall 111, and the end cap 220 covers the opening 205. The end cap 220 is fixedly connected to the end of the side wall 109 at the opening 205. The end cap 220 and the end of the side wall 109 can be welded together, for example, by laser welding. The end cap 220 and the side wall 109 can also be mechanically connected by other mechanical fixing methods. The fixed connection between the end cap 220 and the side wall 109 needs to achieve a fixed and sealed connection. The housing 200 and the end cap 220 together define a receiving cavity, which can be used to receive the electrode assembly 120, as well as the first current collector 210 and the second current collector 230 connected to the electrode assembly 120. The first current collector 210 and the second current collector 230 are connected to the opposite ends of the electrode assembly 120 in its axial direction and can be electrically connected to the positive and negative electrode tabs of the electrode assembly 120, respectively. The receiving cavity can also be used to receive electrolyte and other necessary battery components. The direction from the end cap 220 to the end wall 111 is the height direction of the battery cell 100, and the height direction of the battery cell 100 can be parallel to the axial direction of the electrode assembly 120.

[0030] The terminal 160 can pass through the end wall 111, be fixedly connected to the end wall 111, and be insulated from the end wall 111. In some embodiments, the terminal 160 can be made of a conductive metallic material. For example, the material of the terminal 160 can be aluminum. In some embodiments, the terminal 160 is the positive terminal of the battery cell 100. Electrical insulation between the terminal 160 and the end wall 111 of the housing 200 can be achieved in various ways. For example, insulation can be achieved by placing an insulating gasket assembly between the terminal 160 and the end wall 111.

[0031] Specifically, the outer diameter of the housing 200 can be determined based on the specific dimensions of the electrode assembly 120. For example, the outer diameter of the housing 200 can be 18mm, 21mm, 46mm, etc. The housing 200 can be made of various materials, such as copper, iron, aluminum, steel, or aluminum alloy. The end cap 220 can be made of steel, such as stainless steel or nickel-plated steel, or aluminum alloy or a composite material of steel and aluminum, or other materials that meet the battery energy density requirements while also possessing strength, reliability, and sealing properties. Furthermore, the material can be adjusted to best suit the needs of lightweight battery design. To prevent the housing 200 from rusting during long-term use, a rust-preventive material, such as nickel plating, can be plated onto the surfaces of both the housing 200 and the end cap 220.

[0032] The electrode assembly 120 can be mainly formed by winding a positive electrode sheet and a negative electrode sheet, with a separator provided between the positive and negative electrode sheets. The wound electrode assembly 120 can have a central axial hole 120c, and the electrode assembly 120 and the central axial hole 120c can have a common axis Lx. The positive electrode sheet can include a positive current collector and a positive active material, with the positive active material coated on the surface of the positive current collector; the positive current collector can include a coated area coated with the active material and an uncoated area without the active material, and the uncoated area can be used to form the positive electrode tab of the electrode assembly 120 after winding. The negative electrode sheet includes a negative current collector and a negative active material, with the negative active material coated on the surface of the negative current collector; the negative current collector includes a coated area coated with the active material and an uncoated area without the active material, and the uncoated area can be used to form the negative electrode tab of the electrode assembly 120 after winding. Taking a lithium-ion battery cell as an example, the positive electrode current collector can be made of aluminum, and the positive electrode active material layer includes positive electrode active material, which can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, etc. The negative electrode current collector can be made of copper, and the negative electrode active material layer includes negative electrode active material, which can be carbon or silicon, etc. The separator material can be, for example, PP (polypropylene) or PE (polyethylene). To protect and insulate the electrode assembly 120, an insulating film can be wrapped around the electrode assembly 120. The insulating film can be synthesized from PP, PE, PET (polyethylene terephthalate), PVC (polyvinyl chloride), or other polymer materials.

[0033] A first current collector 210 is disposed between the end cap 220 and the electrode assembly 120. For example, a negative electrode tab of the electrode assembly 120 may face the opening 205, and the negative electrode tab may be welded to the first current collector 210 to electrically connect to the side wall 109 of the housing 200 or the end cap 220 via the first current collector 210. In some embodiments, the first current collector 210 is a negative current collector. A second current collector 230 is disposed between the end wall 111 and the electrode assembly 120. For example, a positive electrode tab of the electrode assembly 120 may face the end wall 111, and the positive electrode tab may be electrically connected to the electrode post 160 via the second current collector 230. In some embodiments, the second current collector 230 is a positive current collector. In some embodiments, the axial directions of the first current collector 210, the second current collector 230, and the electrode assembly 120 may coincide, and they may extend along the axis Lx.

[0034] In some embodiments, such as Figure 2 As shown, the sidewall 109 is provided with a groove 113 adjacent to the end of the sidewall 109 at the opening 205. The groove 113, together with the end wall 111, can restrict the movement of the electrode assembly 120 in the height direction. A first collector 210 can be located between the electrode assembly 120 and the groove 113, and the first collector 210 can be welded to the side of the groove 113 facing the electrode assembly 120. The sidewall 109 is provided with a radially inwardly extending rolled edge 132 on the periphery of the opening 205. The groove 113 and the rolled edge 132 can jointly clamp the end cap 220. The end cap 220 can be insulated and sealed between the groove 113 and the rolled edge 132. In some other embodiments, the end cap 220 can be sealed by laser welding to the sidewall 109, and in this case, the fixing pins of the first collector 210 can be directly welded to the inner wall of the sidewall 109 or the inner wall of the end cap 220.

[0035] An explosion-proof valve may be provided on the end cap 220. In some embodiments, the explosion-proof valve is an annular groove on the surface of the end cap 220 facing the electrode assembly 120. The end cap 220 is thinner at the groove. In some other embodiments, other suitable structures may be used to form the explosion-proof valve.

[0036] During the use of a single battery cell, gas is generated. When the internal gas pressure reaches a certain level, the explosion-proof valve opens, at least partially opening the end cap 220, to release the internal pressure and prevent the battery from exploding. When a single battery cell experiences thermal runaway, the explosion-proof valve must be able to open smoothly to release gas and prevent an explosion, ensuring the battery casing remains intact and preventing the splashing of hard materials that could cause injury to the human body.

[0037] Figure 3 A plan view of a first collector disk according to an embodiment of this application is shown. Figure 3The first collector disk 210A shown can correspond to Figure 2 The first collector disk 210. For the sake of brevity, the first collector disk will be referred to as the collector disk below.

[0038] See Figure 3 As shown, the collector plate 210A includes a plurality of stress-dispersing portions 310 arranged in a ring around the circumference of the collector plate 210A, and an outer ring fixing portion 320 connected between the stress-dispersing portions 310. From the radially outer side to the radially inner side, the stress-dispersing portion 310 may include a fixing pin 360, a stress connecting portion 349, and an electrode pin 340 arranged sequentially. In this way, the fixing pin 360 and the electrode pin 340 of each stress-dispersing portion 310 can be arranged in a one-to-one correspondence in the radial direction. A through groove 390 is formed between the edges of the electrode pins 340 of each stress-dispersing portion 310. The electrode pins 340 can be separated circumferentially by the through groove 390.

[0039] The fixed pin 360 is used for fixed connection with the housing assembly of the battery cell, for example, with the side wall 109 of the housing 200 (see...). Figure 2 Soldering. Electrode pins 340 are used for electrical connection to the electrode assembly of the battery cell. In some embodiments, electrode pins 340 may be soldered to a corresponding tab (e.g., a negative tab) of the electrode assembly. Electrode pins 340 may be areas that fold over when the battery is depressurized.

[0040] The outer ring fixing portion 320 can be connected to the circumferentially outer side of the stress connection portion 349 and can extend circumferentially. The outer ring fixing portion 320 is connected to the circumferentially outer side of the stress connection portion 349, and the outer radial side of the electrode pin 340 can be connected to the stress connection portion 349 and extends radially inward, thus forming a cantilever structure for the electrode pin 340. In the current collector 210A, for example, deformation stress may occur due to the fixed connection between the fixed pin 360 and the housing assembly. By using the outer ring fixing portion 320 to connect a plurality of circumferentially spaced stress dispersing portions 310, stress transmission between each stress dispersing portion 310 can be isolated, thus absorbing and dispersing stress circumferentially. This helps reduce deformation of the disk surface area and avoids stress concentration that could damage the electrical connection between the electrode pin 340 and the electrode assembly, or cause excessive deformation or breakage of the fixed pin 360.

[0041] The current collector 210A includes several stress-dispersing sections 310 arranged circumferentially. Fixed pins 360 and electrode pins 340 are radially aligned in a one-to-one correspondence. The housing welding area on the fixed pins 360 and the electrode welding area on the electrode pins 340 can be located on the same radial path, simultaneously shortening the current transmission path and facilitating DCR control. The radially aligned correspondence between the fixed pins 360 and electrode pins 340 also maximizes the length and coverage area of ​​the electrode pins 340, allowing them to better receive and evenly distribute gas pressure during depressurization, facilitating smooth folding during depressurization. It also allows for unified control of stress transmission caused by the fixed connections of different fixed pins 360 to the housing assembly, preventing wrinkling or warping of the disk surface caused by stress concentration and improving flatness. Furthermore, the fixed connection of the fixed pins 360 during folding provides more stable fixation to the outer side of the electrode pins 340, facilitating smooth folding and opening of the inner ring of the electrode pins 340.

[0042] By forming a through groove 390 between the edges of the electrode pins 340, the through groove 390 can completely separate at least the electrode pins 340 of the stress dispersion section 310. This not only provides ventilation but also improves the tearing efficiency of the material-connecting portion on the disc surface, facilitating the opening of the electrode pins 340 while ensuring stress isolation. The through groove 390 may specifically include a central hole 305 and gap portions 392 that communicate with the central hole 305 and extend at least partially radially. The edges of the electrode pins 340 include two circumferentially opposite side edges 3402 and an inner edge 3401 located radially inward. Each side edge 3402 is a straight edge extending radially. A portion of the gap portion 392, i.e., a first spacing portion 342, is formed between the side edges 3402 of the electrode pins 340. The inner edge 3401 of the electrode pins 340 surrounds and forms the central hole 305. The central hole 305 can be used for electrolyte injection and electrolyte wetting.

[0043] In some embodiments, the inner edge 3401 of the electrode pin 340 is an arc-shaped edge, and a central hole 305 is formed by the arc-shaped edge. The central hole 305 is a circular hole. The arc-shaped edge surrounding the central hole 305 ensures that the central hole 305 has a sufficiently large area to ensure better liquid injection wetting on the collector plate 210A side. In some embodiments, the diameter of the central hole 305 is 5mm-15mm. This diameter range of the central hole 305 can ensure the electrode liquid injection and wetting effect while maximizing the coverage area of ​​the electrode pin 340. The central hole 305 can also be used as a main venting channel to increase the opening efficiency of the explosion-proof valve in the event of thermal runaway inside the battery.

[0044] In some embodiments, the electrode pins 340 are fan-shaped. By constructing the electrode pins 340 in a fan shape and spacing them apart by the gaps 342, the coverage area of ​​the electrode pins 340 can be increased. This better ensures the strength of the current collector 210A, thereby resisting the deformation stress transmitted to the electrode pins 340, preventing the disk surface from warping due to stress, and ensuring the flatness of the disk surface.

[0045] The stress connection portion 349 may specifically include a first connection portion 341 connected to the electrode pin 340, a second connection portion 348 connected to the fixed pin 360, and a transition portion 347 between the first connection portion 341 and the second connection portion 348. The circumferential width of the first connection portion 341 and the second connection portion 348 is smaller than the circumferential width of the transition portion 347. When the fixed pin 360 is fixedly connected to the housing assembly, deformation stress may be generated at the fixed pin 360. The deformation stress is first conducted to the stress connection portion 349, and then transmitted to the electrode pin 340 through the stress connection portion 349. By configuring the first connection portion 341 and the second connection portion 348, which respectively connect the electrode pin 340 and the fixed pin 360, to have smaller widths, they can better buffer, disperse, and absorb stress.

[0046] In some embodiments, the gap 392 extends radially and covers the side edge 3402 of the electrode pin 140 and the side edge of the first connection portion 341. That is, the gap 392 extends to the side edge of the first connection portion 341 and spaces adjacent first connection portions 341. The circumferential width of the gap 392 corresponding to the first connection portion 341 is greater than the circumferential width of the gap 392 corresponding to the electrode pin 140. That is, the width of the gap 392 between the first connection portions 341 is greater than the width of the gap 392 between the electrode pins 140. By providing a wider gap 392 between the first connection portions 341, a narrower circumferential width of the first connection portion 341 can be formed. This can reduce the strength at this first connection portion 341, better buffer and absorb the welding stress from the fixed pin 360, while the remaining width of the first connection portion 341 can still ensure the connection strength between the electrode pin 340 and the transition portion 347, avoiding surface wrinkling or warping.

[0047] More specifically, the gap portion 392 includes a first gap portion 342 located between the side edges 3402 of two adjacent electrode pins 340, and a second gap portion 308 located on opposite sides of the first connecting portion 341 in the circumferential direction. The second gap portion 308 is formed on the radially outer side of the electrode pin 340, and the second gap portion 308 can separate a portion of the outer edge of the electrode pin 340 from the corresponding portion of the outer ring fixing portion 320. The second gap portion 308 can extend circumferentially. The second gap portion 308 can serve as a vent. The second gap portion 308 located on both sides of the first connecting portion 341 can be closer to the outer ring of the electrode assembly, which is beneficial for venting and depressurizing the outer ring of the electrode assembly. The circumferential extension of the second gap portion 308 increases the area of ​​the second gap portion 308, which is more conducive to ensuring venting of the outer ring of the electrode assembly.

[0048] In the secondary battery, the central hole 305 of the current collector 210A can be correspondingly arranged along the axis Lx with the central shaft hole 120c of the electrode assembly 120. The central hole 305 and the central shaft hole 120c of the electrode assembly 120 can be arranged coaxially. As described above, the central hole 305 can serve as the main venting channel of the battery, and the central shaft hole 120c of the electrode assembly 120 can also jointly serve as the main venting channel of the battery. Aligning the central hole 305 with the central shaft hole 120c of the electrode assembly 120 facilitates the folding and opening of the disk surface 340 for smooth pressure release. The second gap portion 308 can be positioned closer to the outer peripheral surface of the electrode assembly 120 relative to the central shaft hole 120c, so that the second gap portion 308 can be used for venting the outer ring of the electrode assembly 120.

[0049] The first gap 342 has a width W1 in the direction perpendicular to the radial direction. In some embodiments, the width W1 ranges from 0.5 mm to 2 mm. If the width W1 of the first gap 342 is less than 0.5 mm, the first gap 342 will be too narrow, and the distance between adjacent electrode pins 340 will be too close, making it impossible for the electrode pins 340 to fold open smoothly during pressure relief. If the width W1 of the first gap 342 is greater than 0.5 mm, the first gap 342 will be too wide, reducing the area of ​​the retained electrode pins 340. By setting the width W1 of the first gap 342 to a range of 0.5 mm to 2 mm, it can be ensured that the electrode pins 340 are independent of each other, and that the electrode pins 340 can fold open smoothly during pressure relief. At the same time, the integrity of the retained electrode pins 340 can be maximized, increasing the area for bearing deformation stress during pressure relief.

[0050] The collector plate 210A may further include an edge groove 309, which is formed at the connection between the second connecting portion 348 and the transition portion 347 and extends inward from the connection. The two edge grooves 309 corresponding to each stress dispersion portion 310 are radially symmetrically arranged, and the two edge grooves 309 extend at an angle. In some embodiments, the distance between the two edge grooves 309 gradually decreases in the direction from the radially outer side to the radially inner side. This makes the width of the second connecting portion 348 between the two edge grooves 309 smaller than the circumferential width of the transition portion 347. By forming the edge grooves 309, stress from the fixed pin 360 can be buffered and absorbed, preventing the plate surface from warping due to stress.

[0051] In some embodiments, the radial width of the second gap 308 is W2, and the value of W2 can range from 1 mm to 3 mm. The minimum distance between the two edge grooves 309 corresponding to a stress dispersion portion 310 is d1, and in some embodiments, the value of distance d1 ranges from 8 mm to 12 mm, for example, it can be 10 mm. The minimum distance between two adjacent second gaps 308 (i.e., the minimum width of the first connecting portion 341) is d2, and the value of distance d2 ranges from 8 mm to 12 mm, for example, it can be 10 mm.

[0052] In some embodiments, the outer diameter of the outer ring fixing portion 320 can range from 35 mm to 45 mm, for example, 40 mm. The inner diameter of the outer ring fixing portion 320 can range from 28 mm to 36 mm, for example, 32 mm. In some embodiments, the outer ring fixing portion 320 and the electrode pin 340 have the same thickness, and the thickness ranges from 0.2 mm to 0.4 mm, for example, 0.2 mm.

[0053] The electrode pin 340 may have a first solder mark 388 formed for soldering with the electrode tab. For the sake of simplicity, the diagram is as follows. Figure 3 The diagram only shows the first solder mark 388 corresponding to one electrode pin 340. The first solder mark 388 may be distributed not only on the electrode pin 340 but also on the stress connection portion 349. In this embodiment, the first solder mark 388 extends continuously from the electrode pin 340 to the stress connection portion 349. In other embodiments, the first solder mark 388 may also be distributed intermittently on the electrode pin 340 and the stress connection portion 349. By distributing the first solder mark 388 from the electrode pin 340 to the stress connection portion 349, the length of the first solder mark 388 can be increased, which can help control the battery's overcurrent and DC internal resistance.

[0054] The fixed pin 360 can be bent relative to the second connecting portion 348. The fixed pin 360 can extend in a circumferential arc along the collector. The fixed pin 360 may have a second solder mark formed by welding to the housing 200, and the second solder mark may be distributed circumferentially. To accommodate the welding of the fixed pin 360 to the housing assembly, the second connecting portion 348 can undergo elastic deformation. The elastic connection of the second connecting portion 348 provides elastic buffering capability to buffer the deformation stress from the fixed pin 360.

[0055] Since the fixed pin 360 can be bent relative to the second connecting portion 348, the fixed pin 360 and the second connecting portion 348 can be arranged at an angle. In some embodiments, the fixed pin 360 and the second connecting portion 348 can be an integral structure. In some embodiments, the angle between the fixed pin 360 and the second connecting portion 348 can be equal to 90° or less than 90°. In some embodiments, the surface 3631 of the fixed pin 360 located outside the angle can be aligned with the groove 113 of the sidewall 109 (see...). Figure 2 Welding is performed on the side facing the electrode assembly. In embodiments employing a grooving sealing method, when welding the fixed pin 360, the fixed pin 360 can be relatively pressed down and deformed. At this time, the second connecting portion 348 can undergo axial elastic deformation to provide deformation buffer and prevent the disk surface from deforming.

[0056] In some embodiments, the maximum width of the second connecting portion 348 is W3, and the value of W3 can range from 4 mm to 14 mm. The maximum width W3 of the second connecting portion 348 can be less than the maximum width of the corresponding electrode pin 340. In some embodiments, the maximum radial distance between two radially opposite fixed pins 360 can be the maximum radial dimension of the current collector 210A, and the maximum radial dimension of the current collector 210A can range from 40 mm to 50 mm, for example, 45 mm. In embodiments where the included angle between the fixed pin 360 and the second connecting portion 348 is 90°, the height of the fixed pin 360 can be in the range of 2.5 mm to 4 mm, for example, 3 mm.

[0057] Figure 4 A plan view of a manifold 210B according to another embodiment of this application is shown. The manifold 210B is comparable to the above-referenced manifold in several aspects. Figure 3 The following description is similar to or the same as the 210A collector panel. Figure 4 The differences between the shown collector panel 210B and the others are as follows. See also: Figure 4 As shown, at least one connecting part 343 is provided in the first gap portion 342, and the connecting part 343 can be used to connect adjacent electrode pins 340. In this embodiment, as an example, two connecting parts 343 are provided in each first gap portion 342.

[0058] If there is no connecting part 343 between the electrode leads 340, the electrode leads 340 are prone to warping and other problems after machining, making it difficult to maintain the flatness of the disk surface, which will affect subsequent welding processes. By setting the connecting part 343, the machining difficulty of the electrode leads 340 can be reduced and a certain structural strength can be provided, preventing the disk surface from warping and maintaining the flatness of the disk surface. At the same time, it can be opened smoothly during venting. The connecting part 343 can also provide holding force in subsequent welding processes, ensuring welding yield and avoiding problems such as poor solder joints or difficulty in accurately controlling the welding depth due to the fit between the electrode leads 340 and the tab.

[0059] The width of each connecting portion 343 may be the same as the width of the first gap portion 342. In some embodiments, the radial length of each connecting portion 343 may be 0.5 mm to 1 mm, for example, 0.5 mm. The two ends of the first gap portion 342 are respectively connected to the central hole 305 and the second gap portion 308. In some embodiments, the distance between the two ends of the first gap portion 342 and the nearest connecting portion 343 may be 0.8 mm to 1.2 mm, for example, 1 mm.

[0060] Figure 5 A plan view of a manifold 210C according to another embodiment of this application is shown. The manifold 210C is comparable to the above-referenced manifold in several aspects. Figure 3 and Figure 4 The described collector panels 210A and 210B are similar or identical. See also Figure 5 As shown, the manifold 210C includes a plurality of stress-dispersing portions 310 spaced circumferentially, and an outer ring fixing portion 320 connected between adjacent stress-dispersing portions 310. From radially outward to radially inward, each stress-dispersing portion 310 may sequentially include a fixing pin 360, a stress connecting portion 349, and an electrode pin 340. The outer ring fixing portion 320 is connected to the stress connecting portion 349, and the electrode pins 340 extend radially inward. A through groove 390 is formed between the electrode pins 340. The through groove 390 includes a central hole 305 and a gap portion 392, the gap portion 392 including a first gap portion 342 and a second gap portion 308.

[0061] The electrode pins 340 are separated by a first gap 342. Unlike the aforementioned manifolds 210A and 210B, in this embodiment, the number of stress-dispersing portions 310 is three. In other embodiments, the number of stress-dispersing portions 310 may be less than three, for example, one or two. By reducing the number of stress-dispersing portions 310, the bending pressure during pressure relief can be more evenly distributed, and the strength of the disk surface can be enhanced.

[0062] Because the number of stress-dispersing parts 310 is reduced, the length of the second gap 308 that connects two adjacent stress-dispersing parts 310 in the circumferential direction can be longer, and the area of ​​the second gap 308 can be larger, that is, the exhaust area of ​​the outer ring can be larger, which is more conducive to ensuring the exhaust of the outer ring of the electrode assembly and can also improve the uneven airflow distribution.

[0063] In this embodiment, the manifold 210C may further include a root slot 332, which may be disposed at the stress connection portion 349 and extend toward the central hole 3305. The root slot 332 may extend radially. Some of the root slots 332 may also be distributed on the electrode pins 340. At least two root slots 332 may be provided in each stress dispersion portion 310, and the at least two root slots 332 are spaced apart in the circumferential direction. By providing root slots 332, it is beneficial to absorb circumferential and radial deformation stress, and improve the problems of disk surface deformation and warping during processing.

[0064] The width of each root slot 332 can range from 0.5 mm to 1 mm, for example, 0.5 mm. In some embodiments, the length of each root slot 332 can range from 8 mm to 12 mm, for example, 10 mm. The two root slots 332 corresponding to one stress dispersion section 310 can extend in parallel. In some embodiments, the distance between the two root slots 332 corresponding to one stress dispersion section 310 can range from 1 mm to 3 mm, for example, 2 mm. The root slots 332 avoid the electrode welding area (specifically, the first solder mark 388) on the electrode pin 340. Each stress dispersion section 310 is provided with two root slots 332, and the stress absorption effect can be increased by increasing the number of root slots 332.

[0065] Figure 6 A plan view of a manifold 210D according to another embodiment of this application is shown. The manifold 210D is comparable to the above-referenced manifold in several aspects. Figures 3 to 5 The described embodiments are similar or identical. See also Figure 6 As shown, the manifold 210D includes a plurality of stress-dispersing portions 310 spaced circumferentially, and an outer ring fixing portion 320 connecting adjacent stress-dispersing portions 310. From radially outward to radially inward, each stress-dispersing portion 310 may sequentially include a fixing pin 360, a stress connecting portion 349, and an electrode pin 340. The outer ring fixing portion 320 is connected to the stress connecting portion 349, and the electrode pins 340 extend radially inward. A through groove 390 is formed between the electrode pins 340. The fixing pins 360 and electrode pins 340 of each stress-dispersing portion 310 may be radially corresponding one-to-one.

[0066] The first gap portion 342 is located circumferentially between two adjacent electrode pins 340, separating the two adjacent electrode pins 340. In this embodiment, the first gap portion 342 is a fan-shaped structure with a gradually increasing width in the radial direction. The electrode pins 340 may have a rectangular shape. The second gap portion 308 between two adjacent first connecting portions 341 may communicate with the first gap portion 342. By providing a large-area first gap portion 342, it is beneficial to absorb deformation forces in the radial direction, which can improve the problem of disc warping during processing.

[0067] Figure 7 A plan view of a manifold 210E according to another embodiment of this application is shown. The manifold 210E is comparable to the above-referenced manifold in several respects. Figure 3 The following description is similar to or the same as the 210A collector panel. Figure 7 The differences between the shown collector panel 210E and the others are as follows. See also: Figure 7 As shown, in this embodiment, a stress-absorbing portion 369 is provided at the connection between the second connecting portion 348 and the transition portion 347. The stress-absorbing portion 369 can be a thinned portion, and the thickness of the manifold 210E at the stress-absorbing portion 369 is less than the thickness at the second connecting portion 348 or the transition portion 347. The stress-absorbing portion 369 can be formed by upsetting, scoring, etc. In some embodiments, the thickness retained after thinning at the stress-absorbing portion 369 can range from 0.08 mm to 1.5 mm, for example, 0.1 mm. The radial width of the stress-absorbing portion 369 is W4, and the width W4 can range from 0.08 mm to 1.5 mm, for example, 0.1 mm.

[0068] By providing a stress-absorbing part 369 at the connection between the second connecting part 348 and the transition part 347, deformation can be buffered, improving the problem of disk warping during processing. Furthermore, if a groove is cut near the fixed pin 360, laser leakage may occur during the welding of the fixed pin 360 to the housing assembly, leading to cell defects. Therefore, grooves are typically cut away from the fixed pin 360. By providing a non-grooved stress-absorbing part 369, laser leakage problems caused by grooving can be avoided.

[0069] See Figure 8 This application provides an electrical device 1000. For ease of explanation, the following embodiments use a vehicle as an example. A battery pack 1002 is installed inside the vehicle. The battery pack 1002 can be located at the bottom, front, or rear of the vehicle body 1001. The battery pack 1002 can be used to power the vehicle; for example, it can serve as the vehicle's operating power source. The battery pack 1002 can include multiple battery cells, such as the battery cell 100 described above.

[0070] The working part of the electrical device 1000 is electrically connected to the battery pack 1002 to obtain electrical power. The vehicle can be a gasoline vehicle, a natural gas vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, but are not limited thereto. The working part is the vehicle body 1001, and the battery pack 1002 is located at the bottom of the vehicle body 1001, providing electrical power for the vehicle's operation or the operation of its internal electrical components. However, in some other embodiments, the electrical device 1000 can also be a mobile phone, portable device, laptop computer, ship, spacecraft, electric toy, and power tool, etc. Spacecraft include airplanes, rockets, space shuttles, etc.; the working part can obtain electrical power from the battery pack 1002 and perform corresponding functions, such as a fan blade rotation unit or a vacuum cleaner suction unit. Electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric boat toys, and electric airplane toys, etc.; power tools include metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc. This application does not impose any special limitations on the aforementioned electrical equipment 1000.

[0071] The above are merely preferred embodiments of this application and are not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A collector disk, characterized in that, The current collection plate includes: a plurality of stress dispersion parts arranged at circumferential intervals and an outer ring fixing part connecting adjacent stress dispersion parts; The stress dispersion section includes: a fixed pin, a stress connection section, and an electrode pin connected sequentially from the radially outer side to the radially inner side. The outer ring fixed section is connected to the stress connection section, and the electrode pin extends toward the radially inner side. The fixed pin is used to be fixedly connected to the housing assembly of the battery cell, and the electrode pin is used to be electrically connected to the electrode assembly of the battery cell. A through groove is formed between the edges of the electrode pin.

2. The collector disk according to claim 1, characterized in that, The through slot includes a central hole and a gap portion that connects to the central hole and extends radially; the electrode pin includes two side edges arranged opposite each other along the circumference and an inner edge located radially inside; the side edges are straight edges extending radially, and the gap portion is formed between the side edges; the inner edge is an arc-shaped edge, and the arc-shaped edge surrounds and forms the central hole, which is a circular hole.

3. The collector disk according to claim 2, characterized in that, The stress connection includes a first connection portion connected to the electrode pin, a second connection portion connected to the fixed pin, and a transition portion between the first connection portion and the second connection portion. The width of the first connection portion and the second connection portion along the circumferential direction is smaller than the width of the transition portion along the circumferential direction.

4. The collector disk according to claim 3, characterized in that, The gap extends radially and covers the side edge of the electrode pin and the side edge of the first connection portion, and the circumferential width of the first connection portion is greater than the circumferential width of the electrode pin.

5. The collector disk according to claim 3, characterized in that, The stress dispersion section further includes: A stress-absorbing section is provided at the connection between the second connecting section and the transition section, and the thickness of the collector plate at the stress-absorbing section is less than the thickness at the second connecting section or the transition section.

6. The collector disk according to claim 4, characterized in that, The gap portion includes a first gap portion located between the side edges of two adjacent electrode pins, and a second gap portion located on opposite sides of the first connection portion in the circumferential direction, the second gap portion extending along the circumferential direction; The fixed pin is bent relative to the second connection portion, and the fixed pin extends along the circumferential arc.

7. The collector disk according to claim 3, characterized in that, The stress dispersion section further includes: An edge groove is formed at the connection between the second connecting part and the transition part. The edge groove extends inward from the outer edge of the connection. The two edge grooves corresponding to each stress dispersion part are symmetrically arranged along the radial direction and at an included angle. The distance between the two edge grooves gradually decreases in the direction from the radial outer side to the radial inner side. The stress dispersion section further includes a root groove, which extends radially and is disposed in the stress connection section, and a portion of the root groove is distributed on the electrode pin; Each of the stress dispersion portions is provided with at least two root slots, and the at least two root slots are spaced apart in the circumferential direction.

8. A single battery cell, characterized in that, include: Housing assembly, defining the receiving cavity; An electrode assembly is disposed within the receiving cavity, and one end of the electrode assembly is provided with an electrode tab. as well as According to any one of claims 1-7, the collector plate is located between the tab of the electrode assembly and the housing assembly, the electrode pin is electrically connected to the tab, the fixed pin is fixedly connected to the housing assembly, the through slot includes a central hole and a gap portion that communicates with the central hole and extends radially, a portion of the gap portion is formed on the radially outer side of the electrode pin, the central hole and the central axial hole of the electrode assembly are correspondingly arranged in the axial direction of the electrode assembly, and the portion of the gap portion is arranged closer to the outer peripheral surface of the electrode assembly than the central axial hole of the electrode assembly.

9. The battery cell according to claim 8, characterized in that, The electrode pin is welded and fixed to the electrode tab. The electrode pin has a first weld mark formed by welding. The first weld mark is distributed on the electrode pin and the stress connection portion. The fixed pin is welded and connected to the housing assembly. The fixed pin has a second weld mark formed by welding. The second weld mark is distributed along the circumferential direction.

10. An electrical appliance, characterized in that, include: The battery cell as described in any one of claims 8-9.

Images