Electrode assembly, winding device, battery cell, battery and electric device

Abstract

The utility model relates to an electrode assembly, a winding device and method, a battery monomer, a battery and a power utilization device, and belongs to the technical field of battery manufacturing. The utility model provides an electrode assembly which comprises a positive pole piece, and the positive pole piece forms a bending area after being wound; wherein the positive pole piece comprises a positive current collector and a positive active material layer arranged on the surface of the positive current collector, the positive active material layer comprises an inactivation region, and at least one part of the inactivation region is located in the bending region. The utility model further provides winding equipment and a manufacturing method of the electrode assembly, and the electrode assembly can be formed. The electrode assembly has good safety performance, the electrode assembly can be formed by winding through the manufacturing method and the winding equipment, industrial production of the electrode assembly can be achieved, and the manufacturing efficiency of the electrode assembly is improved. The utility model further provides a battery monomer, a battery and a power utilization device. The battery monomer comprises the electrode assembly.

Description

Technical Field

[0001] The present application relates to the technical field of battery manufacturing, and in particular to an electrode assembly, a winding device, a battery cell, a battery and an electrical device. Background Art

[0002] With the rapid development of the new energy vehicle industry, the technical level of power batteries has become more and more mature, and the safety performance of power batteries has become one of the important indicators to measure their performance. The wound electrode assembly is an important component inside the battery cell, and the safety performance of the electrode assembly plays a decisive role in the safety performance of the battery cell. However, on the one hand, the existing electrode assembly is prone to lithium deposition during the charging process and has poor safety performance; on the other hand, even if the structure of the electrode assembly is improved to improve the safety performance of the battery cell, there is currently no corresponding winding equipment, resulting in the inability to achieve industrial production even if the structure of the electrode assembly is improved. Utility Model Content

[0003] To this end, the present application proposes an electrode assembly, a winding device, a battery cell, a battery and an electrical device. The electrode assembly has good safety performance, and the winding device can wind and form the electrode assembly, which can realize the industrialized production of the electrode assembly and improve the manufacturing efficiency of the electrode assembly.

[0004] The first aspect of the present application proposes an electrode assembly, including a positive electrode plate, wherein the positive electrode plate forms a bending zone after being wound; wherein the positive electrode plate includes a positive electrode collector and a positive electrode active material layer arranged on the surface of the positive electrode collector, the positive electrode active material layer includes a deactivation zone, and at least a portion of the deactivation zone is located in the bending zone.

[0005] In the electrode assembly of the embodiment of the present application, since at least a part of the deactivation area of ​​the positive electrode active material layer is located in the bending area of ​​the positive electrode sheet, the effective active area of ​​the positive electrode active material layer in the bending area of ​​the positive electrode sheet can be reduced, thereby improving the CB value of the bent part of the electrode assembly (that is, the ratio of the negative electrode active material capacity on the opposite side to the positive electrode active material capacity), so that the lithium ions deintercalated from the positive electrode active material layer during the charging process of the battery cell can be effectively embedded in the corresponding negative electrode active material layer, thereby alleviating the lithium plating phenomenon in the bent part of the electrode assembly, thereby improving the safety performance of the electrode assembly.

[0006] According to some embodiments of the present application, the positive current collector includes an inner side surface facing the axis of the electrode assembly and an outer side surface away from the axis of the electrode assembly, the positive active material layer includes a first positive active material layer arranged on the inner side surface of the positive current collector and a second positive active material layer arranged on the outer side surface of the positive current collector, and the first positive active material layer includes the deactivation zone.

[0007] In the above scheme, since the area of ​​the first positive electrode active material layer arranged on the inner side of the positive electrode collector is larger than the area of ​​the negative electrode active material layer of the corresponding negative electrode collector, the deactivation zone is arranged in the first positive electrode active material layer, which can reduce the effective active area of ​​the first positive electrode active material layer, and increase the CB value between the outer side of the negative electrode sheet and the inner side of the positive electrode sheet in the bent part of the electrode assembly, so that most of the lithium ions deintercalated from the first positive electrode active material layer during the charging process of the battery cell can be embedded in the corresponding negative electrode active material layer, which alleviates the lithium plating phenomenon between the inner side of the positive electrode collector and the inner negative electrode collector, thereby improving the safety performance of the electrode assembly.

[0008] According to some embodiments of the present application, the deactivation zone is located at the positive electrode plate of the innermost circle of the electrode assembly.

[0009] In the above scheme, the radius of curvature of the innermost circle of the positive electrode sheet is the smallest, resulting in the largest area ratio between the positive electrode active material layer on the inner side of the innermost circle of the positive electrode sheet and the negative electrode active material layer of the negative electrode sheet on the corresponding inner circle. A deactivation zone is set on the innermost circle of the positive electrode sheet, which can significantly improve the CB value between the inner side of the innermost circle of the positive electrode sheet and the negative electrode sheet on its inner side, so that the lithium ions deintercalated from the positive electrode active material layer during the charging process of the battery cell can be effectively embedded in the corresponding negative electrode active material layer, slowing down the lithium decomposition phenomenon and improving the safety performance of the electrode assembly.

[0010] According to some embodiments of the present application, the number of the deactivation zones is at least two, and at least two of the deactivation zones are spaced apart and distributed along the winding direction.

[0011] In the above scheme, each circle of the positive electrode sheet includes two bending areas around the winding direction, and each bending area is provided with a deactivation area, thereby alleviating the lithium deposition phenomenon of the bending part of the electrode assembly and improving the safety performance of the electrode assembly.

[0012] The second embodiment of the present application provides a battery cell, comprising the electrode assembly described in the first embodiment of the present application.

[0013] Since the bending area of ​​the positive electrode plate in the electrode assembly of the first embodiment of the present application has a deactivation area, the lithium deposition phenomenon in the bending part of the electrode assembly can be alleviated, and the safety performance of the electrode assembly can be improved, so that the battery cell including the electrode assembly also has good safety performance.

[0014] The third embodiment of the present application provides a battery, comprising the battery cell described in the second embodiment of the present application.

[0015] Since the bending area of ​​the positive electrode plate of the electrode assembly used in the battery cell of the second embodiment of the present application has a deactivation area, the lithium plating phenomenon in the bending part of the electrode assembly can be alleviated, and it has better safety performance, so that the battery including the battery cell also has better safety performance.

[0016] The fourth aspect of the present application provides an electrical device, comprising the battery described in the third aspect of the present application, wherein the battery is used to provide electrical energy.

[0017] Since the battery of the third aspect embodiment of the present application has a deactivation zone in the bending area of ​​the positive electrode plate of the electrode assembly used in the battery cell, the lithium plating phenomenon in the bending part of the electrode assembly can be alleviated, and it has better safety performance, so that the electrical device including the battery also has better safety performance.

[0018] The fifth aspect embodiment of the present application proposes a winding device, including: a winding device for winding a positive electrode sheet; a deactivation device, which is arranged upstream of the winding device along the tape running direction of the positive electrode sheet, and the deactivation device is configured to provide a deactivating agent to the positive electrode sheet to deactivate the positive active material of a part of the positive active material layer of the positive electrode sheet.

[0019] In the winding equipment of the embodiment of the present application, the deactivation device can provide a deactivating agent to the positive electrode sheet to deactivate the positive electrode active material of a part of the positive electrode active material layer of the positive electrode sheet to form a deactivation zone, so that the positive electrode sheet wound by the winding equipment when winding the electrode assembly has a deactivation zone, thereby being able to form the electrode assembly in the embodiment of the first aspect of the present application, realizing the industrial production of such electrode assembly, and improving the forming efficiency of such electrode assembly.

[0020] According to some embodiments of the present application, the deactivation device is configured to provide a deactivation agent to a side of the positive electrode sheet facing the winding device.

[0021] In the above scheme, the deactivation device provides a deactivating agent to the side of the positive electrode sheet facing the winding device, so that after the positive electrode sheet enters the winding device, the inner side facing the winding device is located on the side facing the winding axis, and the deactivation zone is located in the first positive electrode active material layer on the inner side of the positive electrode collector, thereby improving the CB value between the outer side of the negative electrode sheet and the inner side of the positive electrode sheet, alleviating the lithium plating phenomenon between the inner side of the positive electrode collector and the negative electrode collector of the negative electrode sheet inside it, thereby improving the safety performance of the electrode assembly.

[0022] According to some embodiments of the present application, the deactivation device includes: a clamping mechanism for clamping the positive electrode sheet and providing the deactivation agent to the positive electrode sheet; and a driving mechanism for driving the clamping mechanism to move synchronously with the positive electrode sheet.

[0023] In the above scheme, the driving mechanism drives the clamping mechanism to move synchronously with the positive electrode sheet, and can continuously provide the deactivating agent to the positive electrode sheet within the time range that the clamping mechanism follows the movement of the positive electrode sheet, so as to ensure the deactivation effect of the positive active material layer of the positive electrode sheet and form an effective deactivation zone.

[0024] According to some embodiments of the present application, the clamping mechanism includes: a bracket; a first clamping part and a second clamping part, which are arranged on the bracket; and a first driving member, which is arranged on the bracket and is used to drive the first clamping part and the second clamping part to move closer to or away from each other to clamp or release the positive electrode sheet; wherein at least one of the first clamping part and the second clamping part is configured to provide the deactivating agent to the positive electrode sheet.

[0025] In the above solution, the first clamping part and the second clamping part jointly clamp the positive electrode sheet and provide the deactivation agent to the positive electrode sheet, which can improve the position accuracy of the deactivation zone and form an effective deactivation zone at a preset position of the positive electrode sheet.

[0026] According to some embodiments of the present application, at least one of the first clamping part and the second clamping part is a porous material.

[0027] In the above scheme, the porous material can store the deactivating agent, and when the first clamping part and the second clamping part jointly clamp the positive electrode sheet, they can squeeze the porous material to squeeze the deactivating agent from the porous material to the surface of the positive electrode sheet, and when the positive electrode sheet is released, the deactivating agent remaining on the surface of the positive electrode sheet is sucked back, which not only maintains the cleanliness of the surface of the positive electrode sheet, but also can recycle the deactivating agent.

[0028] According to some embodiments of the present application, the driving mechanism includes: a screw rod, which is arranged along the running direction of the positive electrode plate, and the screw rod passes through the bracket and is threadedly engaged with the bracket; a second driving member, which is used to drive the screw rod to rotate so that the bracket moves along the axial direction of the screw rod.

[0029] In the above scheme, the rotation of the screw can drive the bracket to rotate along the axial direction of the screw, thereby driving the clamping mechanism to move synchronously with the positive electrode sheet, which has a simple structure and is easy to assemble.

[0030] According to some embodiments of the present application, the deactivation device includes at least two clamping mechanisms spaced apart along the tape-traveling direction of the positive electrode sheet, and the driving mechanism is used to drive at least two clamping mechanisms to move synchronously.

[0031] In the above scheme, each clamping mechanism corresponds to a deactivation zone, and the driving mechanism drives at least two clamping mechanisms to move synchronously, so that at least two clamping mechanisms can jointly clamp the positive electrode sheet and move with the positive electrode sheet to form at least two deactivation zones at the same time, thereby improving the formation efficiency of the deactivation zone.

[0032] According to some embodiments of the present application, the deactivation device further includes: a detection mechanism for detecting position information of the positive electrode plate; and a controller for controlling the actions of the clamping mechanism and the driving mechanism according to the position information detected by the detection mechanism.

[0033] In the above scheme, by setting up a detection mechanism, the position information of the positive electrode sheet can be detected, the controller can determine the preset position of the deactivation zone of the positive electrode sheet, and control the clamping mechanism to accurately perform the clamping action and control the driving mechanism to drive the clamping mechanism to move synchronously with the positive electrode sheet, which can improve the position accuracy of the deactivation zone and form an effective deactivation zone at the preset position of the positive electrode sheet. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0035] Figure 1 Shown is a simplified schematic diagram of a vehicle in one embodiment of the present application;

[0036] Figure 2 It is shown that Figure 1 A schematic diagram of the structure of the battery of the vehicle;

[0037] Figure 3 It is shown that Figure 2 A schematic diagram of the structure of a battery cell in the battery;

[0038] Figure 4 Shown is a structural diagram of an electrode assembly in some embodiments of the present application;

[0039] Figure 5 It is shown that Figure 4 A partial enlarged view of the middle A;

[0040] Figure 6 Shown is a structural diagram of another form of electrode assembly in some embodiments of the present application;

[0041] Figure 7Shown is a schematic diagram of winding the positive electrode sheet and the negative electrode sheet in the electrode assembly of some embodiments of the present application;

[0042] Figure 8 Shown is a schematic diagram of winding a positive electrode sheet in an electrode assembly of some embodiments of the present application;

[0043] Fig. 9 Shown is a structural schematic diagram of another form of a positive electrode sheet in an electrode assembly of some embodiments of the present application;

[0044] Fig.10 Shown is a schematic structural diagram of another positive electrode sheet of an electrode assembly of some embodiments of the present application;

[0045] Fig.11 Shown is a schematic structural diagram of another positive electrode sheet of an electrode assembly of some embodiments of the present application;

[0046] Fig.12 Shown is a schematic structural diagram of another positive electrode sheet of an electrode assembly of some embodiments of the present application;

[0047] Fig.13 Shown is a schematic structural diagram of another positive electrode sheet of an electrode assembly of some embodiments of the present application;

[0048] Fig.14 It shows Fig.13 A partial enlarged view of point B in the middle;

[0049] Fig.15 Shown is an isometric view of a deactivation device of a winding device according to some embodiments of the present application;

[0050] Fig.16 Shown is a front view of a deactivation device of a winding device according to some embodiments of the present application;

[0051] Fig.17 Shown is a top view of a deactivation device of a winding device according to some embodiments of the present application;

[0052] Fig.18 Shown is an isometric view of a deactivation device provided with a liquid supply mechanism of a winding device according to some embodiments of the present application;

[0053] Fig.19 Shown is a schematic diagram of a method for manufacturing an electrode assembly according to some embodiments of the present application;

[0054] Fig. 20 Shown is a schematic diagram of a method for deactivating a positive electrode active material layer in a method for manufacturing an electrode assembly according to some embodiments of the present application;

[0055] In the drawings, the drawings are not drawn to scale.

[0056] Marking description: 1000-vehicle; 100-battery; 110-battery cell; 111-housing; 1111-housing; 1112-cover; 1113-electrode terminal; 112-electrode assembly; 1121-positive electrode plate; 11211-positive current collector; 11212-positive active material layer; 11213-first inner side; 11214-first outer side; 11215-first positive active material layer; 11216-second positive active material layer; 11217-bending area; 11218-straight area; 1122-negative electrode plate; 11221-negative current collector; 11222-negative active material layer; 1123-first diaphragm; 1124-second diaphragm; 11219-bending area; 11220-straight area; 11221-negative electrode plate; 11222-negative current collector; 11222-negative active material layer; 1123-first diaphragm; 1124-second diaphragm; 1125-first inner side; 1126-first outer side; 1127-bending area; 1128-straight area; 1129-negative electrode plate; 11211-negative current collector; 11222-negative active material layer; 1123-first diaphragm; 1124-second diaphragm; 1125-first inner side; 1126-first outer side; 1127-bending area; 1128-straight area; 1129-negative electrode plate; 11212-negative electrode 251-straight part; 11252-bent part; 1127-deactivation zone; 1128-active zone; 1129-ear; 120-housing; 121-first housing; 122-second housing; 200-controller; 300-motor; 2000-winding device; 2100-winding device; 2200-deactivation device; 2210-clamping mechanism; 2211-bracket; 2212-first clamping part; 2213-second clamping part; 2214-first driving member; 2220-driving mechanism; 2221-screw; 2222-second driving member; 2230-detection mechanism; 2240-frame; 2250-liquid supply mechanism; 2251-liquid storage container; 2252-pump. DETAILED DESCRIPTION

[0057] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0058] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as those commonly understood by technicians in the technical field to which this application belongs; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned drawings and any variations thereof are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary and secondary relationship.

[0059] Reference to "embodiments" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described in this application may be combined with other embodiments.

[0060] It should be noted that in the description of this application, unless otherwise clearly specified and limited, the terms "installation", "connection", "connection", and "attachment" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0061] The term "plurality" used in the present application refers to two or more (including two).

[0062] In the present application, battery cells may include lithium-ion secondary batteries, lithium-ion primary batteries, lithium-sulfur batteries, sodium-lithium-ion batteries, sodium-ion batteries or magnesium-ion batteries, etc., and the embodiments of the present application do not limit this. Battery cells may be cylindrical, flat, rectangular or other shapes, etc., and the embodiments of the present application do not limit this. Battery cells are generally divided into three types according to the packaging method: cylindrical battery cells, square battery cells and soft-pack battery cells.

[0063] The battery mentioned in the embodiments of the present application refers to a single physical module including one or more battery cells to provide higher voltage and capacity. For example, the battery mentioned in the present application may include a battery module or a battery pack. The battery generally includes a box for encapsulating one or more battery cells, and the box can prevent liquid or other foreign matter from affecting the charging or discharging of the battery cells.

[0064] The battery cell includes an electrode assembly and an electrolyte. The battery cell mainly relies on the movement of metal ions between the positive electrode sheet and the negative electrode sheet to work. The positive electrode sheet includes a positive electrode collector and a positive electrode active material layer, and the positive electrode active material layer is coated on the surface of the positive electrode collector. The negative electrode sheet includes a negative electrode collector and a negative electrode active material layer, and the negative electrode active material layer is coated on the surface of the negative electrode collector. Among them, the electrode assembly is a winding structure.

[0065] The CB value refers to the ratio of the negative electrode active material capacity to the positive electrode active material capacity of the opposite negative electrode plate, and also refers to the ratio of the effective active area of ​​the negative electrode active material layer of the opposite negative electrode plate to the effective active area of ​​the positive electrode active material capacity.

[0066] In the related art, after the electrode assembly is wound and formed, there is an area difference between the positive electrode sheet and the negative electrode sheet at the bent portion of the electrode assembly within the same angle range, which is prone to lithium deposition and poses certain safety hazards.

[0067] After research, the inventors found that if the gap between the positive electrode sheet and the negative electrode sheet at the bent part of the electrode assembly becomes larger, for example, the negative electrode sheet collapses inward or the positive electrode sheet loosens outward, etc., it will cause the CB of the outer side of the negative electrode sheet at the bent part and the positive electrode sheet corresponding to the outer side to decrease, so that the lithium ions deintercalated from the positive electrode active material layer during the charging process of the battery cell cannot be fully embedded in the corresponding negative electrode active material layer, thereby causing lithium plating.

[0068] Based on the above ideas, the inventor of the present application proposed a technical solution, which forms a deactivation zone on the surface of the positive electrode sheet in the bent part of the electrode assembly, which can reduce the effective area of ​​the positive electrode active material layer in the bent area of ​​the positive electrode sheet, thereby improving the CB value of the bent part of the electrode assembly, so that the lithium ions deintercalated from the positive electrode active material layer during the charging process of the battery cell can be effectively embedded in the corresponding negative electrode active material layer, thereby alleviating the lithium plating phenomenon in the bent part of the electrode assembly, thereby improving the safety performance of the electrode assembly.

[0069] It is understandable that the battery cells described in the embodiments of the present application can directly supply power to electrical devices, or can form a battery by connecting in parallel or in series to supply power to various electrical devices in the form of a battery.

[0070] It can be understood that the electrical devices using battery cells or batteries described in the embodiments of the present application can be in various forms, for example, mobile phones, portable devices, laptops, electric vehicles, electric cars, ships, spacecraft, electric toys and electric tools, etc. For example, spacecraft include airplanes, rockets, space shuttles and spacecraft, etc. Electric toys include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys and electric airplane toys, etc. Electric tools include metal cutting electric tools, grinding electric tools, assembly electric tools and railway electric tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators and electric planers.

[0071] The battery cells and batteries described in the embodiments of the present application are not limited to the electrical devices described above, but can also be applied to all electrical devices using battery cells and batteries. However, for the sake of simplicity, the following embodiments are described using electric vehicles as examples.

[0072] Figure 1 Shown is a simplified schematic diagram of a vehicle in one embodiment of the present application; Figure 2 It shows Figure 1Schematic diagram of the structure of the battery of a vehicle.

[0073] like Figure 1 As shown, a battery 100, a controller 200 and a motor 300 are arranged inside the vehicle 1000. For example, the battery 100 can be arranged at the bottom, front or rear of the vehicle 1000. The vehicle 1000 can be a fuel vehicle, a gas vehicle or a new energy vehicle. The new energy vehicle can be a pure electric vehicle, a hybrid vehicle or an extended range vehicle.

[0074] In some embodiments of the present application, the battery 100 can be used to power the vehicle 1000, for example, the battery 100 can be used as an operating power source for the vehicle 1000. The controller 200 is used to control the battery 100 to power the motor 300, for example, to meet the power requirements of the vehicle 1000 during startup, navigation, and driving.

[0075] In other embodiments, the battery 100 can not only serve as an operating power source for the vehicle 1000 , but also serve as a driving power source for the vehicle 1000 , replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000 .

[0076] The battery 100 mentioned in the embodiments of the present application refers to a single physical module including one or more battery cells 110 to provide higher voltage and capacity. For example, the battery 100 is formed by connecting a plurality of battery cells 110 in series or in parallel.

[0077] The battery 100 includes a plurality of battery cells 110 and a housing 120 . The plurality of battery cells 110 are connected in parallel, in series or in a mixed combination to achieve high voltage output. The plurality of battery cells 110 are assembled and placed inside the housing 120 .

[0078] The box 120 includes a first box 121 and a second box 122. The first box 121 and the second box 122 are covered with each other to form a battery cavity, and multiple battery modules are placed in the battery cavity. Multiple battery cells 110 are connected in parallel, series or mixed and placed in the box 120 formed by the first box 121 and the second box 122 being buckled together.

[0079] Figure 3 It is shown that Figure 2 Schematic diagram of the structure of a battery cell in the battery.

[0080] like Figure 3As shown, each battery cell 110 includes a shell 111, an electrode assembly 112 and two electrode terminals 1113. The shell 111 may be a hexahedron or other shapes, and a receiving cavity is formed inside the shell 111 for receiving the electrode assembly 112 and the electrolyte. The shell 111 includes a shell 1111 and a cover 1112, and one end of the shell 1111 has an opening so that the electrode assembly 112 can be placed inside the shell 1111 through the opening. The shell 1111 may be made of a metal material, such as aluminum, aluminum alloy or nickel-plated steel. Two electrode terminals 1113 are provided on the cover 1112. Of the two electrode terminals 1113, one is a positive electrode terminal 1113 and the other is a negative electrode terminal 1113. The shell 1111 may be a rectangular parallelepiped, or a cylinder or an elliptical cylinder. The two electrode terminals 1113 may be both disposed on the cover 1112 , or both disposed on the housing 1111 , or one may be disposed on the cover 1112 and the other disposed on the housing 1111 .

[0081] The electrode assembly 112 is disposed inside the housing 111 , and includes two tabs 1129 with opposite polarities. The positive electrode terminal 1113 is connected to the tab 1129 of the positive electrode of the electrode assembly 112 , and the negative electrode terminal 1113 is connected to the tab 1129 of the negative electrode of the electrode assembly 112 .

[0082] Figure 4 Shown is a structural diagram of an electrode assembly in some embodiments of the present application; Figure 5 It is shown that Figure 4 A partial enlarged view of point A in the middle.

[0083] like Figure 3 , Figure 4 and Figure 5 As shown, the electrode assembly 112 includes a positive electrode sheet 1121, a negative electrode sheet 1122, a first separator 1123 and a second separator 1124. The first separator 1123 and the second separator 1124 are used to separate the adjacent positive electrode sheet 1121 and the negative electrode sheet 1122. The positive electrode sheet 1121, the negative electrode sheet 1122, the first separator 1123 and the second separator 1124 are wound to form the electrode assembly 112. The winding axis of the electrode assembly 112 is the first axis P.

[0084] The positive electrode plate 1121 includes a positive electrode collector 11211 and a positive electrode active material layer 11212, and the positive electrode active material layer 11212 is coated on the surface of the positive electrode collector 11211; the negative electrode plate 1122 includes a negative electrode collector 11221 and a negative electrode active material layer 11222, and the negative electrode active material layer 11222 is coated on the surface of the negative electrode collector 11221. Taking a lithium-ion battery as an example, the material of the positive electrode collector 11211 can be aluminum, and the positive electrode active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium or lithium manganese oxide. The portion of the positive electrode collector 11211 that is not coated with the positive electrode active material layer 11212 protrudes from the portion that is coated with the positive electrode active material layer 11212, and the portion of the positive electrode collector 11211 that is not coated with the positive electrode active material layer 11212 serves as the positive electrode tab 1129 (please refer to Figure 3 The negative electrode current collector 11221 may be made of copper, and the negative electrode active material may be carbon or silicon. The portion of the negative electrode current collector 11221 not coated with the negative electrode active material layer 11222 protrudes from the portion coated with the negative electrode active material layer 11222, and the portion of the negative electrode current collector 11221 not coated with the negative electrode active material layer 11222 serves as the negative electrode tab 1129 (see Figure 3 ). In order to ensure that a large current does not melt, the number of positive electrode tabs 1129 is multiple and stacked together, and the number of negative electrode tabs 1129 is multiple and stacked together. The material of the diaphragm can be PP (polypropylene) or PE (polyethylene).

[0085] like Figure 4 As shown, in some embodiments of the present application, the electrode assembly 112 is flat, and on a plane perpendicular to its winding axis, the length direction of the electrode assembly 112 is direction X, and the width direction is direction Y. Specifically, the electrode assembly 112 includes a straight portion 11251 and a bent portion 11252 located on both sides of the straight portion 11251 along direction X, and the two bent portions 11252 each have an arc surface. The electrode assembly 112 can be directly wound into a flat shape, or it can be wound into a circular or elliptical shape and then the middle part thereof is compacted so that the middle part of the electrode assembly 112 forms a straight portion 11251.

[0086] Figure 6 Shown is a structural diagram of another form of electrode assembly in some embodiments of the present application.

[0087] like Figure 6 As shown, in other embodiments, the electrode assembly 112 may also be cylindrical, and the electrode assembly 112 only includes the bent portion 11252 .

[0088] The positive electrode sheet 1121 , the negative electrode sheet 1122 and the separator each have a bending structure corresponding to the bending portion of the electrode assembly 112 , and the portion where the positive electrode sheet 1121 is wound around the bending portion of the electrode assembly 112 is a bending region 11217 .

[0089] For example, Figure 4 As shown, for the flat electrode assembly 112, the positive electrode sheet 1121 forms two bending areas 11217 each time it is wound one circle. The two bending areas 11217 correspond to the two bending parts 11252 of the electrode assembly 112 respectively. The part between the two bending areas 11217 is the straight area 11218 and corresponds to the straight part 11251 of the electrode assembly 112.

[0090] It is understandable that one circle in the present application means that a certain point of the electrode assembly 112 is taken as the starting point, and a circle is made along the winding direction to reach another point, and the line connecting the other point and the starting point extends along the radial direction of the electrode assembly 112. A half circle in the present application means half of a circle, and those skilled in the art should understand the meaning of other numbers of circles, which will not be further described here.

[0091] Figure 7 Shown is a schematic diagram of winding the positive electrode sheet and the negative electrode sheet in the electrode assembly of some embodiments of the present application; Figure 8 Shown is a schematic diagram of the winding of the positive electrode sheet in the electrode assembly of some embodiments of the present application.

[0092] like Figure 7 and Figure 8 As shown, some embodiments of the present application provide an electrode assembly 112, including a positive electrode sheet 1121, which is wound to form a bending area 11217. The positive electrode sheet 1121 includes a positive current collector 11211 and a positive active material layer 11212 disposed on the surface of the positive current collector 11211, and the positive active material layer 11212 includes a deactivation area 1127, at least a portion of the deactivation area 1127 is located in the bending area 11217.

[0093] The positive electrode active material layer 11212 includes an active area 1128 and an inactivation area 1127. The active area 1128 is an area that deintercalates lithium ions during the charge and discharge process and has active material capacity; the inactivation area 1127 refers to a part of the positive electrode active material layer that loses its activity, that is, the positive electrode active material layer 11212 in this area no longer deintercalates lithium ions during the charge and discharge process. There are many ways to form the inactivation area 1127 on the positive electrode active material layer 11212. For example, an acidic solution such as dilute hydrochloric acid can be sprayed on the position of the positive electrode active material layer 11212 for forming the inactivation area 1127, or an insulating liquid such as liquid glue can be used to infiltrate the position of the positive electrode active material layer 11212 for forming the inactivation area 1127.

[0094] The deactivation zone 1127 may only exist in the bending zone 11217 of the positive electrode sheet 1121 to improve the lithium deposition phenomenon in the bent portion of the electrode assembly 112; based on the aforementioned implementation that the electrode assembly 112 is flat, a circle of the positive electrode sheet 1121 is provided with two bending zones 11217, and each bending zone 11217 is provided with a deactivation zone 1127. The deactivation zone 1127 may also exist in the straight zone 11218 of the positive electrode sheet 1121 while existing in the bending zone 11217 of the positive electrode sheet 1121, and the area of ​​the positive active material layer 11212 is further reduced in the straight zone 11218, so that the lithium ions deintercalated from the positive active material layer 11212 can be fully embedded in the negative active material layer 11222 of the corresponding negative electrode sheet 1122, thereby avoiding the lithium deposition phenomenon in the straight portion 11251 of the electrode assembly 112; for example, Figure 8 As shown, based on the aforementioned implementation mode in which the electrode assembly 112 is flat, the innermost circle of the positive electrode plate 1121 extends from the winding end around the winding direction and sequentially forms a partial straight area 11218 and a bent area 11217, and the partial straight area 11218 and the bent area 11217 are provided with a continuous deactivation area 1127.

[0095] like Figure 8 As shown, the deactivation zone 1127 may also exist simultaneously on the inner side of the positive electrode sheet 1121 facing the first axis P and on the outer side away from the first axis P, so that the corresponding CB values ​​on both sides of the positive electrode sheet 1121 are improved. The deactivation zone 1127 may be arranged on the inner side of the winding axis (i.e., the first axis P) of the positive electrode sheet 1121 facing the electrode assembly 112 to improve the CB value between the negative electrode sheet 1122 and the outer positive electrode sheet 1121. The deactivation zone 1127 may also be arranged on the outer side of the positive electrode sheet 1121 away from the first axis P to improve the CB value between the negative electrode sheet 1122 and the inner positive electrode sheet 1121.

[0096] The positive electrode sheet 1121 is a multi-turn winding structure, the end of the positive electrode sheet 1121 close to the first axis P is the winding end, and the end located on the outer peripheral side of the positive electrode sheet 1121 is the tail end. The deactivation area 1127 can be set at the part of the positive electrode sheet 1121 close to the winding end, or at other parts.

[0097] In the electrode assembly 112 of the embodiment of the present application, since at least a portion of the deactivation area 1127 of the positive electrode active material layer 11212 is located in the bending area 11217 of the positive electrode plate 1121, the effective active area of ​​the positive electrode active material layer 11212 in the bending area 11217 of the positive electrode plate 1121 can be reduced, thereby improving the CB value of the bent portion of the electrode assembly 112 (that is, the ratio of the negative electrode active material capacity on the opposite side to the positive electrode active material capacity), so that the lithium ions deintercalated from the positive electrode active material layer 11212 during the charging process of the battery cell 110 can be effectively embedded in the corresponding negative electrode active material layer 11222, thereby alleviating the lithium plating phenomenon in the bent portion of the electrode assembly 112, thereby improving the safety performance of the electrode assembly 112.

[0098] Fig. 9 Shown is a structural schematic diagram of another form of a positive electrode plate in an electrode assembly of some embodiments of the present application.

[0099] like Fig. 9 As shown, in some embodiments of the present application, the positive electrode current collector 11211 includes an inner side surface facing the axis of the electrode assembly 112 (i.e., the first axis P) and an outer side surface away from the axis of the electrode assembly 112 (i.e., the first axis P), the positive electrode active material layer 11212 includes a first positive electrode active material layer 11215 arranged on the inner side surface of the positive electrode current collector 11211 and a second positive electrode active material layer 11216 arranged on the outer side surface of the positive electrode current collector 11211, and the first positive electrode active material layer 11215 includes a deactivation zone 1127.

[0100] Specifically, if Fig. 9 As shown, along the thickness direction of the positive current collector 11211, the side of the positive current collector 11211 facing the first axis P is the first inner side 11213, and the side away from the first axis P is the first outer side 11214. The first inner side 11213 of the positive current collector 11211 is provided with a first positive active material layer 11215, and the first outer side 11214 is provided with a second positive active material layer 11216. Similarly, along the thickness direction of the negative current collector 11221, the inner side of the negative current collector 11221 facing the first axis P is provided with a first negative active material layer (not shown in the figure), and the outer side of the negative current collector 11221 away from the first axis P is provided with a second negative active material layer (not shown in the figure). The first positive electrode active material layer 11215 is arranged corresponding to the second negative electrode active material layer, and the deactivation zone 1127 is arranged in the first positive electrode active material layer 11215, which can increase the CB value between the first positive electrode active material layer 11215 and the second negative electrode active material layer, thereby avoiding lithium precipitation.

[0101] In the above scheme, since the area of ​​the first positive active material layer 11215 arranged on the inner side of the positive current collector 11211 is larger than the area of ​​the negative active material layer 11222 of the corresponding negative current collector 11221, the deactivation zone 1127 is arranged on the first positive active material layer 11215, which can reduce the effective active area of ​​the first positive active material layer 11215, and increase the CB value between the outer side of the negative electrode sheet 1122 and the inner side of the positive electrode sheet 1121 in the bent part of the electrode assembly 112, so that most of the lithium ions deintercalated from the first positive active material layer 11215 during the charging process of the battery cell 110 can be embedded in the corresponding negative active material layer 11222, thereby alleviating the lithium plating phenomenon between the inner side of the positive current collector 11211 and the inner negative current collector 11221, thereby improving the safety performance of the electrode assembly 112.

[0102] Fig.10 Shown is a schematic structural diagram of another positive electrode sheet of an electrode assembly of some embodiments of the present application; Fig.11 Shown is a schematic structural diagram of another positive electrode plate of an electrode assembly of some embodiments of the present application.

[0103] like Fig.10 As shown, in some embodiments of the present application, the deactivation zone 1127 is located at the positive electrode plate 1121 of the innermost circle of the electrode assembly 112 .

[0104] like Fig.10 As shown, the innermost circle of the positive electrode sheet 1121 of the electrode assembly 112 refers to a circle extending from the winding end of the positive electrode sheet 1121 to the winding end around the winding direction, that is, the part of the positive electrode sheet 1121 from V1 to V2.

[0105] like Fig.10 As shown, the deactivation zone 1127 can be located both inside and outside the innermost positive electrode plate 1121; Fig.11 As shown, the deactivation zone 1127 may also be located on the inner side of the innermost circle of the positive electrode plate 1121 , or the deactivation zone 1127 may also be located on the outer side of the innermost circle of the positive electrode plate 1121 .

[0106] In the above scheme, the radius of curvature of the innermost circle of the positive electrode sheet 1121 is the smallest, resulting in the largest area ratio between the positive electrode active material layer 11212 on the inner side of the innermost circle of the positive electrode sheet 1121 and the negative electrode active material layer 11222 of the corresponding inner circle of the negative electrode sheet 1122. A deactivation zone 1127 is set on the innermost circle of the positive electrode sheet 1121, which can significantly improve the CB value between the inner side of the innermost circle of the positive electrode sheet 1121 and the negative electrode sheet 1122 inside it, so that the lithium ions deintercalated from the positive electrode active material layer 11212 during the charging process of the battery cell 110 can be effectively embedded in the corresponding negative electrode active material layer 1122, thereby slowing down the lithium decomposition phenomenon and improving the safety performance of the electrode assembly 112.

[0107] Fig.12 Shown is a schematic structural diagram of another positive electrode sheet of an electrode assembly of some embodiments of the present application; Fig.13 Shown is a schematic structural diagram of another positive electrode plate of the electrode assembly of some embodiments of the present application.

[0108] like Fig.12 As shown, in some embodiments of the present application, the number of the deactivation zones 1127 is at least two, and at least two deactivation zones 1127 are spaced apart along the winding direction.

[0109] At least two inactivation regions 1127 may be respectively disposed in different bending regions 11217. Fig.12 As shown, based on the aforementioned implementation in which the electrode assembly 112 is flat, two bending areas 11217 of a circle of positive electrode sheets 1121 are respectively provided with a deactivation area 1127. As a preferred implementation, the number of deactivation areas 1127 is two, and the two bending areas 11217 of the innermost circle of the positive electrode sheet 1121 are respectively provided with a deactivation area 1127, which can significantly improve the lithium deposition phenomenon of the innermost circle of the positive electrode sheet 1121.

[0110] The at least two deactivation zones 1127 may have a portion of the deactivation zones 1127 disposed in the bending zone and another portion disposed in the straight zone. For example, based on the aforementioned embodiment in which the deactivation zone 1127 is disposed in the innermost positive electrode sheet 1121, the innermost positive electrode sheet 1121 has continuous deactivation zones 1127 disposed in the straight zone and the bending zone.

[0111] At least two deactivation zones 1127 may also be arranged in the same bending zone, and at least two deactivation zones 1127 are spaced apart along the winding direction. For example, based on the aforementioned embodiment in which the electrode assembly 112 is cylindrical, the circumferential region around the first axis P of the electrode assembly 112 is all a bending portion, and the plurality of deactivation zones 1127 are spaced apart along the length direction of the positive electrode sheet 1121.

[0112] In the above scheme, each circle of the positive electrode sheet 1121 includes two bending areas around the winding direction, and each bending area is provided with a deactivation area 1127, thereby alleviating the lithium deposition phenomenon of the bending part of the electrode assembly 112 and improving the safety performance of the electrode assembly 112.

[0113] In other embodiments, the number of the deactivation zone 1127 may be one, and one deactivation zone 1127 is disposed in the bending zone 11217 of the positive electrode plate 1121 or exists continuously in the adjacent bending zone 11217 and the straight zone 11218 .

[0114] Some embodiments of the present application provide a battery cell 110 including an electrode assembly 112 .

[0115] Since the bending area of ​​the positive electrode sheet 1121 in the electrode assembly 112 has a deactivation area 1127, the lithium deposition phenomenon in the bending part of the electrode assembly 112 can be alleviated, and the safety performance of the electrode assembly 112 can be improved, so that the battery cell 110 including the electrode assembly 112 also has good safety performance.

[0116] Some embodiments of the present application provide a battery 100 including a battery cell 110 .

[0117] Since the bending area of ​​the positive electrode sheet 1121 of the electrode assembly 112 used in the battery cell 110 has a deactivation area 1127, the lithium deposition phenomenon of the bending part of the electrode assembly 112 can be alleviated, and it has better safety performance, so that the battery 100 including the battery cell 110 also has better safety performance.

[0118] Some embodiments of the present application provide an electrical device, including a battery 100 , where the battery 100 is used to provide electrical energy.

[0119] Since the bending area of ​​the positive electrode sheet 1121 of the electrode assembly 112 used in the battery cell 110 of the battery 100 has a deactivation area 1127, the lithium deposition phenomenon of the bending part of the electrode assembly 112 can be alleviated, and it has better safety performance, so that the electrical device including the battery 100 also has better safety performance.

[0120] Fig.13 Shown is a schematic structural diagram of a winding device according to some embodiments of the present application; Fig.14 It shows Fig.13 A partial enlarged view of point B in the middle.

[0121] Some embodiments of the present application propose a winding device 2000, including a winding device 2100 and a deactivation device 2200, the winding device 2100 is used to wind the positive electrode sheet 1121; along the running direction of the positive electrode sheet 1121, the deactivation device 2200 is arranged upstream of the winding device 2100, and the deactivation device 2200 is configured to provide a deactivating agent to the positive electrode sheet 1121 to deactivate the positive active material of a part of the positive active material layer 11212 of the positive electrode sheet 1121.

[0122] It can be understood that the process of winding the electrode assembly 112 in some embodiments of the present application includes but is not limited to relying on the winding device 2000 in the embodiments of the present application to be implemented; the winding device 2000 in the embodiments of the present application includes but is not limited to being used for winding the electrode assembly 112 in some embodiments of the present application.

[0123] The winding device 2000 further includes a feeding device corresponding to the positive electrode sheet 1121, the negative electrode sheet 1122, the first separator 1123 and the second separator 1124, which is arranged upstream of the winding device 2100 and is used to respectively provide the positive electrode sheet 1121, the negative electrode sheet 1122, the first separator 1123 and the second separator 1124. The positive electrode sheet 1121, the negative electrode sheet 1122, the first separator 1123 and the second separator 1124 enter the winding device 2100 from the upstream of the winding device 2100 to be wound into the electrode assembly 112. The upstream of the winding device 2100 refers to the incoming side of the winding device 2100, that is, the side of the winding device 2100 facing the feeding device.

[0124] The running direction of the positive electrode sheet 1121 refers to the direction in which the positive electrode sheet 1121 enters the winding device 2100 from the corresponding feeding device when the winding device 2100 rotates along the second direction M to wind the electrode assembly 112, that is, the first direction Q. The deactivation device 2200 extends along the first direction Q to provide a deactivating agent to the surface of the positive electrode sheet 1121 traveling along the first direction Q, and forms a deactivation area 1127 on the positive active material layer 11212 of the positive electrode sheet 1121.

[0125] The deactivation device 2200 can provide the deactivation agent to the surfaces of both sides of the positive electrode sheet 1121; the deactivation device 2200 can also provide the deactivation agent to the surface of one side of the positive electrode sheet 1121. The deactivation device 2200 can provide the deactivation agent in a stationary manner, and the positive electrode sheet 1121 passes through the deactivation device 2200 and forms a deactivation zone 1127 when moving along the first direction Q; the deactivation device 2200 can also move synchronously with the positive electrode sheet 1121 to continuously provide the deactivation agent to the surface of the positive electrode sheet 1121. The deactivation device 2200 can provide the deactivation agent to the positive electrode sheet 1121 by single-sided spraying, pressing, etc.; the deactivation device 2200 can also clamp the positive electrode sheet 1121 from both sides in the thickness direction and provide the deactivation agent to the surface of the positive electrode sheet 1121.

[0126] The deactivator may be an acidic solution, such as dilute hydrochloric acid, etc.; the deactivator may also be an insulating solution, such as liquid glue, etc.

[0127] In the winding device 2000 of the embodiment of the present application, the deactivation device 2200 can provide a deactivating agent to the positive electrode sheet 1121 to deactivate the positive active material of a part of the positive active material layer 11212 of the positive electrode sheet 1121 to form a deactivation zone 1127, so that the positive electrode sheet 1121 wound by the winding device 2000 when winding the electrode assembly 112 has the deactivation zone 1127, so that the electrode assembly 112 in some embodiments of the present application can be formed, the industrial production of such electrode assembly 112 can be realized, and the forming efficiency of such electrode assembly 112 can be improved.

[0128] like Fig.13 and Fig.14 As shown, in some embodiments of the present application, the deactivation device 2200 is configured to provide a deactivation agent to a side of the positive electrode sheet 1121 facing the winding device 2100 .

[0129] Specifically, after the first separator 1123, the negative electrode sheet 1122 and the second separator 1124 have been stacked and wound in the winding device 2100, the positive electrode sheet 1121 enters the winding device 2100 from the side of the second separator 1124 facing the winding device 2100. The side of the positive electrode sheet 1121 facing the winding device 2100 refers to the side of the positive electrode sheet 1121 away from the second separator 1124. After the positive electrode sheet 1121 is wound in the winding device 2100, the side of the positive electrode sheet 1121 facing the winding device 2100 is the inner side of the positive electrode sheet 1121, and the corresponding positive active material layer 11212 is the first active positive active material layer 11212.

[0130] In the above scheme, the deactivation device 2200 provides a deactivating agent to the side of the positive electrode sheet 1121 facing the winding device 2100, so that after the positive electrode sheet 1121 enters the winding device 2100, the inner side of the positive electrode sheet 1121 facing the winding device 2100 is located on the side facing the winding axis, and the deactivation area 1127 is located on the first positive electrode active material layer 11215 on the inner side of the positive electrode current collector 11211 (please refer to Figure 8 ), improve the CB value between the outer side of the negative electrode plate 1122 and the inner side of the positive electrode plate 1121, alleviate the lithium deposition phenomenon between the inner side of the positive electrode collector 11211 and the negative electrode collector 11221 of the negative electrode plate 1122 on its inner side, thereby improving the safety performance of the electrode assembly 112.

[0131] Fig.15 Shown is an isometric view of a deactivation device of a winding device according to some embodiments of the present application; Fig.16 Shown is a front view of a deactivation device of a winding device according to some embodiments of the present application; Fig.17 Shown is a top view of a deactivation device of a winding apparatus according to some embodiments of the present application.

[0132] like Fig.15 , Fig.16 and Fig.17 As shown, in some embodiments of the present application, the deactivation device 2200 includes a clamping mechanism 2210 and a driving mechanism 2220 , wherein the clamping mechanism 2210 is used to clamp the positive electrode plate 1121 and provide a deactivating agent to the positive electrode plate 1121 , and the driving mechanism 2220 is used to drive the clamping mechanism 2210 to move synchronously with the positive electrode plate 1121 .

[0133] The driving mechanism 2220 can be a linear driving component in various forms, such as a linear cylinder, an electric push rod, a motor screw nut mechanism, etc., to drive the clamping mechanism 2210 to move along the first direction Q.

[0134] The clamping mechanism 2210 clamps the positive electrode sheet 1121 from both sides in the thickness direction of the positive electrode sheet 1121 and presses the end with the deactivating agent against the positive active material layer 11212 of the positive electrode sheet 1121 to provide the deactivating agent to the surface of the positive electrode sheet 1121 .

[0135] The number of clamping mechanisms 2210 can be one, and the driving mechanism 2220 drives one clamping mechanism 2210 to move along the first direction Q; the number of clamping mechanisms 2210 can also be multiple, and multiple clamping mechanisms 2210 are arranged at intervals along the first direction Q, and the driving mechanism 2220 drives multiple clamping mechanisms 2210 to move synchronously.

[0136] In the above scheme, the driving mechanism 2220 drives the clamping mechanism 2210 to move synchronously with the positive electrode sheet 1121, and can continuously provide the deactivating agent to the positive electrode sheet 1121 within the time range of the clamping mechanism 2210 following the movement of the positive electrode sheet 1121, so as to ensure the deactivation effect of the positive electrode active material layer 11212 of the positive electrode sheet 1121, and form an effective deactivation zone 1127 (please refer to Figure 8 ).

[0137] like Fig.15 and Fig.16 As shown, in some embodiments of the present application, the clamping mechanism 2210 includes a bracket 2211, a first clamping portion 2212, a second clamping portion 2213 and a first driving member 2214, the first clamping portion 2212, the second clamping portion 2213 and the first driving member 2214 are all arranged on the bracket 2211, and the first driving member 2214 is used to drive the first clamping portion 2212 and the second clamping portion 2213 to move closer to or away from each other to clamp or release the positive electrode sheet 1121; wherein, at least one of the first clamping portion 2212 and the second clamping portion 2213 is configured to provide a deactivating agent to the positive electrode sheet 1121.

[0138] Specifically, the deactivation device 2200 further includes a frame 2240, the driving mechanism 2220 and the bracket 2211 are both mounted on the bracket 2211, and there is a gap between the first clamping portion 2212 and the second clamping portion 2213 for the positive electrode sheet 1121 to pass through. The thickness direction of the positive electrode sheet 1121 is the third direction N, and two first driving members 2214 are provided, and each first driving member 2214 drives the corresponding clamping portion to move along the third direction N to achieve the first clamping portion 2212 and the second clamping portion 2213 to move closer or farther away; the first clamping portion 2212 and the second clamping portion 2213 may also be the second clamping portion 2213 fixedly mounted on the bracket 2211, and the first clamping portion 2212 is mounted on the execution end of the first driving member 2214, and the first driving member 2214 drives the first clamping portion 2212 to move closer to or farther away from the second clamping portion 2213 along the third direction N.

[0139] One of the first clamping portion 2212 and the second clamping portion 2213 can provide a deactivating agent, and the other can support the positive electrode sheet 1121. Fig.15 and Fig.16As shown, based on the aforementioned implementation method of the deactivation device 2200 providing a deactivating agent to one side surface of the positive electrode sheet 1121, the second clamping portion 2213 is fixedly mounted on the bracket 2211, the first driving member 2214 is mounted on the bracket 2211, the first driving member 2214 drives the first clamping portion 2212 to approach the second clamping portion 2213 to clamp the positive electrode sheet 1121, so as to press the positive electrode sheet 1121 against the second clamping portion 2213, and the first clamping portion 2212 provides a deactivating agent to the surface of the positive electrode sheet 1121, so as to form a deactivation zone 1127 on one side surface of the positive electrode sheet 1121.

[0140] The first clamping portion 2212 and the second clamping portion 2213 can both provide a deactivating agent. For example, based on the aforementioned implementation of the deactivating device 2200 providing the deactivating agent to both side surfaces of the positive electrode sheet 1121, the first clamping portion 2212 and the second clamping portion 2213 can provide the deactivating agent to the surface of the positive electrode sheet 1121 when jointly clamping the positive electrode sheet 1121, so as to form a deactivating zone 1127 on both side surfaces of the positive electrode sheet 1121.

[0141] The first driving member 2214 can be a common linear driving mechanism 2220 such as a linear cylinder or an electric push rod. The second clamping portion 2213 can be slidably matched with the bracket 2211, or can be independently provided with the bracket 2211.

[0142] In the above solution, the first clamping portion 2212 and the second clamping portion 2213 jointly clamp the positive electrode sheet 1121 and provide a deactivating agent to the positive electrode sheet 1121 , which can improve the position accuracy of the deactivating zone 1127 and form an effective deactivating zone 1127 at a preset position of the positive electrode sheet 1121 .

[0143] In some embodiments of the present application, at least one of the first clamping portion 2212 and the second clamping portion 2213 is a porous material.

[0144] The porous material can absorb the deactivating agent and release the deactivating agent under squeezing. The porous material can be a sponge or other elastic porous materials.

[0145] One of the first clamping part 2212 and the second clamping part 2213 is a porous material for providing the deactivating agent to the surface of the positive electrode sheet 1121. For example, based on the implementation of the first clamping part 2212 providing the deactivating agent to one side surface of the positive electrode sheet 1121, the first clamping part 2212 is a storage member, the storage member is a porous material, and the second clamping part 2213 is a pad; based on the implementation of the first clamping part 2212 and the second clamping part 2213 providing the deactivating agent to both sides of the positive electrode sheet 1121 respectively, the first clamping part 2212 and the second clamping part 2213 are both porous materials.

[0146] Fig.18 Shown is an isometric view of a deactivation device provided with a liquid supply mechanism of a winding device according to some embodiments of the present application.

[0147] like Fig.18 As shown, further, the inactivation device 2200 may also include a liquid supply mechanism 2250, which includes a liquid storage container 2251 and a pump 2252. The liquid storage container 2251 is connected to the inactivation device 2200 through the pump 2252, and the inactivation agent is added to the porous material of the inactivation device 2200 by means of the pump 2252.

[0148] In the above scheme, the porous material can store the deactivating agent, and when the first clamping portion 2212 and the second clamping portion 2213 jointly clamp the positive electrode sheet 1121, they can squeeze the porous material to squeeze the deactivating agent from the porous material to the surface of the positive electrode sheet 1121, and when the positive electrode sheet 1121 is released, the deactivating agent remaining on the surface of the positive electrode sheet 1121 is sucked back, which not only maintains the cleanliness of the surface of the positive electrode sheet 1121, but also can recycle the deactivating agent.

[0149] In other embodiments, the surface of one of the first clamping portion 2212 or the second clamping portion 2213 may also have a liquid outlet, which is connected to the liquid supply mechanism 2250 , and the deactivating agent flows out of the liquid outlet by means of pump 2252 .

[0150] like Fig.15 , Fig.16 and Fig.17 As shown, in some embodiments of the present application, the driving mechanism 2220 includes a screw rod 2221 and a second driving member 2222. The screw rod 2221 is arranged along the running direction of the positive electrode plate 1121 (i.e., the first direction Q). The screw rod 2221 passes through the bracket 2211 and is threadedly engaged with the bracket 2211. The second driving member 2222 is used to drive the screw rod 2221 to rotate so that the bracket 2211 moves along the axial direction of the screw rod 2221 (i.e., the first direction Q).

[0151] Specifically, the length direction of the screw rod 2221 extends along the first direction Q, the two ends of the screw rod 2221 are rotatably mounted on the frame, and the second driving member 2222 is fixed to the frame and is used to drive the screw rod 2221 to rotate around its own axis. The bracket 2211 of the clamping mechanism 2210 is provided with a threaded hole, and the screw rod 2221 is threadedly matched with the threaded hole. When the screw rod 2221 rotates, it can drive the clamping mechanism 2210 to move along the first direction Q.

[0152] The second driving member 2222 may be a motor, and the motor is in transmission cooperation with the end of the screw rod 2221 .

[0153] In the above scheme, the rotation of the screw rod 2221 can drive the bracket 2211 to rotate along the axial direction of the screw rod 2221, thereby driving the clamping mechanism 2210 to move synchronously with the positive electrode plate 1121, which has a simple structure and is easy to assemble.

[0154] In some embodiments of the present application, the deactivation device 2200 includes at least two clamping mechanisms 2210 spaced apart along the running direction (ie, the first direction Q) of the positive electrode plate 1121, and the driving mechanism 2220 is used to drive the at least two clamping mechanisms 2210 to move synchronously.

[0155] Based on the aforementioned implementation mode in which the driving mechanism 2220 includes a screw rod 2221 and a second driving member 2222, the brackets 2211 of the multiple clamping mechanisms 2210 can all be threadedly matched with the screw rod 2221. When the screw rod 2221 rotates, it drives the multiple clamping mechanisms 2210 to move synchronously in the same direction, and one clamping mechanism 2210 forms a corresponding deactivation zone 1127.

[0156] like Fig.17 As shown, for example, the electrode assembly 112 is provided with two deactivation zones 1127, and the two deactivation zones 1127 are respectively located at the two bending zones of the innermost circle of the positive electrode plate 1121 of the electrode assembly 112, two clamping mechanisms 2210 are provided, one clamping mechanism 2210 corresponds to one deactivation zone 1127, and the spacing between the two clamping mechanisms 2210 is the same as the spacing between the two bending zones of the innermost circle of the positive electrode plate 1121, and the extension length of the storage component along the first direction Q is the extension length of one deactivation zone 1127, that is, the extension length of one bending zone.

[0157] In the above scheme, each clamping mechanism 2210 corresponds to a deactivation zone 1127, and the driving mechanism 2220 drives at least two clamping mechanisms 2210 to move synchronously, so that at least two clamping mechanisms 2210 can jointly clamp the positive electrode sheet 1121 and move with the positive electrode sheet 1121 to simultaneously form at least two deactivation zones 1127, thereby improving the formation efficiency of the deactivation zones 1127.

[0158] like Fig.17 As shown, in some embodiments of the present application, the deactivation device 2200 also includes a detection mechanism 2230 and a controller (not shown in the figure), the detection mechanism 2230 is used to detect the position information of the positive electrode plate 1121, and the controller is used to control the action of the clamping mechanism 2210 and the driving mechanism 2220 according to the position information detected by the detection mechanism 2230.

[0159] Along the first direction Q, the detection mechanism 2230 is located upstream of the deactivation device 2200, that is, on the side close to the feeding device. The positive electrode sheet 1121 first passes through the detection mechanism 2230 and then enters the deactivation device 2200 during its movement. When the positive electrode sheet 1121 passes through the detection mechanism 2230, the detection mechanism 2230 can detect the marking part of the positive electrode sheet 1121 and send the position information of the positive electrode sheet 1121. The controller can calculate the time for the clamping mechanism 2210 to clamp the positive electrode sheet 1121, the time when the clamping mechanism 2210 starts to move with the positive electrode sheet 1121, the speed at which the clamping mechanism 2210 moves synchronously with the positive electrode sheet 1121, and the time when the clamping mechanism 2210 releases the positive electrode sheet 1121 based on the received position information of the positive electrode sheet 1121 combined with parameters such as the tape running speed of the positive electrode sheet 1121, so as to realize the automatic formation of the deactivation zone 1127.

[0160] In the above scheme, by setting up the detection mechanism 2230, the position information of the positive electrode plate 1121 can be detected, and the controller can determine the preset position of the deactivation zone 1127 of the positive electrode plate 1121, and control the clamping mechanism 2210 to accurately perform the clamping action and control the driving mechanism 2220 to drive the clamping mechanism 2210 to move synchronously with the positive electrode plate 1121, which can improve the position accuracy of the deactivation zone 1127 and form an effective deactivation zone 1127 at the preset position of the positive electrode plate 1121.

[0161] Fig.19 Shown is a schematic diagram of a method for manufacturing an electrode assembly according to some embodiments of the present application.

[0162] like Fig.19 As shown, some embodiments of the present application provide a method for manufacturing an electrode assembly, comprising:

[0163] S100: Providing a positive electrode sheet 1121;

[0164] S200: inactivating a portion of the positive electrode active material layer 11212 of the positive electrode plate 1121;

[0165] S300: Winding the positive electrode sheet 1121 .

[0166] It is understood that the manufacturing method of the electrode assembly 112 in the embodiment of the present application includes but is not limited to the use of the winding device 2000 in the embodiment of the present application, and the manufacturing method of the electrode assembly 112 in the embodiment of the present application includes but is not limited to winding the electrode assembly 112 in the embodiment of the present application. For the convenience of description, this embodiment further describes the manufacturing method of the electrode assembly 112 in conjunction with the winding device 2000.

[0167] Before winding the positive electrode sheet 1121 in S300, the manufacturing method of the electrode assembly 112 includes:

[0168] S400: providing a first diaphragm 1123 and a second diaphragm 1124;

[0169] S500: Winding the first diaphragm 1123 and the second diaphragm 1124 using the winding device 2100;

[0170] S600: providing a negative electrode sheet 1122;

[0171] S700 : The negative electrode sheet 1122 enters between the first separator 1123 and the second separator 1124 , and the first separator 1123 , the negative electrode sheet 1122 and the second separator 1124 are wound and stacked, with the second separator 1124 being located on the side of the negative electrode sheet 1122 facing the winding device 2100 .

[0172] Before the positive electrode sheet 1121 is wound in S300 , the first separator 1123 , the negative electrode sheet 1122 and the second separator 1124 have been stacked and wound in the winding device 2100 , and the positive electrode sheet 1121 with the deactivated area 1127 finally enters the winding device 2100 to continue winding to form the electrode assembly 112 .

[0173] In other embodiments, S200 deactivates a portion of the positive active material layer 11212 of the positive electrode plate 1121 and may also form a deactivation zone 1127 at other locations of the positive active material layer 11212 of the positive electrode plate 1121 to form a corresponding electrode assembly 112, which is not further described herein.

[0174] S300 wound positive electrode sheet 1121 includes:

[0175] S310 : After the negative electrode sheet 1122 is wound at least one circle, the positive electrode sheet 1121 enters the side of the second separator 1124 facing the winding device 2100 .

[0176] After the negative electrode sheet 1122 is wound at least one circle, the positive electrode sheet 1121 enters the winding device 2100. The inner side of the innermost circle of the positive electrode sheet 1121 is provided with the negative electrode sheet 1122, and a deactivation zone 1127 is formed on the inner side of the positive electrode sheet 1121, which can effectively alleviate the lithium deposition phenomenon on the inner side of the innermost circle of the positive electrode sheet 1121 and improve the safety performance of the electrode assembly 112.

[0177] The manufacturing method of the electrode assembly 112 of the embodiment of the present application can manufacture an electrode assembly 112 in which at least a portion of the deactivation zone 1127 of the positive electrode plate 1121 of the electrode assembly 112 is located in the bending zone, thereby alleviating the lithium deposition phenomenon in the bending portion of the electrode assembly 112 and having better safety performance.

[0178] Fig. 20Shown is a schematic diagram of a method for deactivating a positive electrode active material layer in a method for manufacturing an electrode assembly in some embodiments of the present application.

[0179] like Fig. 20 As shown, in some embodiments of the present application, S200: inactivating a portion of the positive electrode active material layer 11212 of the positive electrode plate 1121, including:

[0180] S210 : providing an acidic solution to the positive electrode sheet 1121 to inactivate a portion of the positive electrode active material layer of the positive electrode sheet 1121 .

[0181] In the above scheme, an acidic solution is provided to the positive electrode plate 1121, and a portion of the positive electrode active material layer 11212 is inactivated by acid-base neutralization. This not only forms the deactivation zone 1127 simply and efficiently, but also maintains the original shape of the positive electrode active material layer 11212, making the surface of the positive electrode active material layer 11212 smooth, further alleviating the lithium deposition phenomenon of the bent part of the electrode assembly 112 while ensuring the working performance of the battery 100 assembly.

[0182] In some embodiments of the present application, S200 inactivates a portion of the positive electrode active material layer 11212 of the positive electrode plate 1121, including:

[0183] S220 : forming a deactivation region 1127 in the bending region of the positive electrode plate 1121 .

[0184] The deactivation area 1127 is formed in the bending area of ​​the positive electrode sheet 1121 , which can improve the lithium deposition phenomenon in the bending area, thereby improving the safety performance of the electrode assembly 112 .

[0185] In other embodiments, the deactivating agent may also be an insulating solution, and the insulating solution is used to soak the portion of the active material layer where the deactivation area 1127 is to be formed, so as to make it inactive.

[0186] In some embodiments of the present application, S220 forms a deactivation area 1127 in the bending area of ​​the positive electrode sheet 1121, including:

[0187] S221: Deactivate the two bending areas on the inner side of the innermost positive electrode plate 1121.

[0188] By inactivating the two bending areas on the inner side of the innermost positive electrode sheet 1121, the CB value of the innermost positive electrode sheet 1121 and the inner negative electrode sheet 1122 can be increased, thereby alleviating the lithium deposition phenomenon between the innermost positive electrode sheet 1121 and the inner negative electrode sheet 1122.

[0189] like Figures 4 to 13As shown, some embodiments of the present application provide an electrode assembly 112, which is flat. Along the direction X, the electrode assembly 112 includes a straight portion 11251 and bent portions 11252 on both sides of the straight portion 11251. The electrode assembly 112 includes a first separator 1123, a negative electrode sheet 1122, a second separator 1124, and a positive electrode sheet 1121, which are stacked and wound, wherein the portion of the positive electrode sheet 1121 corresponding to the bent portion 11252 is a bent area 11217. The inner surface of the positive electrode sheet 1121 has a first positive active material layer 11215, and the first positive active material layer 11215 is formed with a deactivated area 1127 by acid-base neutralization, and at least a portion of the deactivated area 1127 is located in the bent area 11217.

[0190] Preferably, the inner surface of the innermost circle (i.e., the V1-V2 portion) of the positive electrode sheet 1121 faces the outer surface of the negative electrode sheet 1122, and the inner surfaces of the two bending areas 11217 of the innermost circle of the positive electrode sheet 1121 are respectively formed with deactivation areas 1127, which can reduce the CB value between the two bending areas 11217 of the innermost circle of the positive electrode sheet 1121 and the negative electrode sheet 1122 therein, alleviate the lithium plating phenomenon there, and improve the safety performance of the electrode assembly 112.

[0191] like Figures 15 to 20As shown, some embodiments of the present application provide a winding device 2000, including a winding device 2100 and a deactivation device 2200, the winding device 2100 is used to wind the positive electrode sheet 1121, along the tape-feeding direction (i.e., the first direction Q) of the positive electrode sheet 1121, the deactivation device 2200 is arranged upstream of the winding device 2100, and corresponds to the side of the positive electrode sheet 1121 facing the winding device 2100. The deactivation device 2200 includes a clamping mechanism 2210, a driving mechanism 2220, a detection mechanism 2230, a frame 2240, and a liquid supply mechanism 2250. There are two clamping mechanisms 2210, and the driving mechanism 2220 is a motor screw nut mechanism. The driving mechanism 2220 simultaneously drives the two clamping mechanisms 2210 to move along the first direction Q to follow the synchronous movement of the positive electrode sheet 1121. The clamping mechanism 2210 includes a bracket 2211, a first clamping part 2212, a second clamping part 2213 and a first driving member 2214. The bracket 2211 is installed on the frame 2240, the second clamping part 2213 is fixedly installed on the bracket 2211, and the execution end of the first driving member 2214 is installed with the first clamping part 2212. The first clamping part 2212 is a porous material such as sponge, and the first clamping part 2212 is impregnated with a deactivating agent. When the positive electrode sheet 1121 moves along the first direction Q, the detection mechanism 2230 detects the position information of the positive electrode sheet 1121, and the controller calculates the position that needs to be deactivated. When the positive electrode sheet 1121 passes through the clamping mechanism 2210, the clamping mechanism 2210 clamps the positive electrode sheet 1121 and moves synchronously. Since the first clamping part 2212 is pressed on the surface of the positive electrode sheet 1121 for a certain period of time, the deactivator can be fully in contact with the positive active material layer 11212 of the positive electrode sheet 1121 to form an effective deactivation zone. Then the first clamping part 2212 is released, the positive electrode sheet 1121 continues to move forward, and the clamping mechanism 2210 is reset.

[0192] The spacing between the two clamping mechanisms 2210 corresponds to the length of the material strip between the two innermost bending areas of the positive electrode sheet 1121 of the electrode assembly 112, and the positive electrode sheet 1121 can simultaneously form two deactivation areas 1127 after passing through the deactivation device 2200. The second clamping portion 2213 and the entire deactivation device 2200 are corrosion-resistant and have a longer service life.

[0193] The method of using the winding device 2000 of the embodiment of the present application is as follows:

[0194] The winding device rotates along the second direction M, and the first diaphragm 1123 and the second diaphragm 1124 are stacked and enter the winding device 2100;

[0195] After the first separator 1123 and the second separator 1124 are wound at least one circle, the negative electrode sheet 1122 is inserted between the first separator 1123 and the second separator 1124 to enter the winding device 2100;

[0196] After the negative electrode sheet 1122 is wound at least once, the positive electrode sheet 1121 moves along the first direction Q and passes through the deactivation device 2200. After the deactivation device 2200 detects the position information of the positive electrode sheet 1121, the clamping mechanism 2210 accurately clamps the positive electrode sheet 1121 when passing through the clamping mechanism 2210 at the position of the preset deactivation zone. The first clamping part 2212 provides an acidic substance to the surface of the positive electrode sheet 1121. The clamping mechanism 2210 moves synchronously with the positive electrode sheet 1121 for a period of time to form two deactivation zones 1127 on the inner side of the positive electrode sheet 1121.

[0197] The clamping mechanism 2210 releases the positive electrode sheet 1121 , and the positive electrode sheet 1121 continues to move along the first direction Q and is inserted into the side of the second separator 1124 facing the winding device 2100 . The winding device 2100 continues to wind and form the electrode assembly 112 .

[0198] In the electrode assembly 112 manufactured by the winding device 2000 and the manufacturing method of the electrode assembly, the inner sides of the two innermost bending areas 11217 of the positive electrode sheet 1121 are respectively provided with a deactivation area 1127, which can reduce the CB value between the two innermost bending areas 11217 of the positive electrode sheet 1121 and the negative electrode sheet 1122 inside, alleviate the lithium deposition phenomenon at the location, and improve the safety performance of the electrode assembly 112. In addition, the winding device 2000 and the manufacturing method can realize the industrialized production of the electrode assembly 112, and improve the manufacturing efficiency of the electrode assembly 112.

[0199] Although the present application has been described with reference to preferred embodiments, various modifications may be made thereto and parts thereof may be replaced with equivalents without departing from the scope of the present application. In particular, the various technical features mentioned in the various embodiments may be combined in any manner as long as there are no structural conflicts. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. An electrode assembly, characterized in that: It includes a positive electrode sheet, wherein the positive electrode sheet is wound to form a bending area; Among them, the positive electrode plate includes a positive electrode collector and a positive electrode active material layer arranged on the surface of the positive electrode collector, the positive electrode active material layer includes a deactivation zone, at least a portion of the deactivation zone is located in the bending zone, and at least a portion of the deactivation zone is located in the positive electrode plate of the innermost circle of the electrode assembly.

2. The electrode assembly according to claim 1, characterized in that: The positive electrode current collector includes an inner side surface facing the axis of the electrode assembly and an outer side surface away from the axis of the electrode assembly, the positive electrode active material layer includes a first positive electrode active material layer arranged on the inner side surface of the positive electrode current collector and a second positive electrode active material layer arranged on the outer side surface of the positive electrode current collector, and the first positive electrode active material layer includes the deactivation zone.

3. The electrode assembly according to claim 1 or 2, characterized in that: The deactivation zone is located at the positive electrode plate of the innermost circle of the electrode assembly.

4. The electrode assembly according to claim 1, characterized in that: The number of the deactivation zones is at least two, and at least two of the deactivation zones are spaced apart and distributed along the winding direction.

5. A battery cell, characterized in that: The invention comprises an electrode assembly as claimed in any one of claims 1 to 4.

6. A battery, characterized in that: Comprising the battery cell as claimed in claim 5.

7. An electrical device, characterized in that: Comprising a battery as claimed in claim 6, the battery is used to provide electrical energy.

8. A winding device, characterized in that: include: A winding device, used for winding the positive electrode sheet, wherein the positive electrode sheet forms a bending area after being wound; A deactivation device is arranged upstream of the winding device along the conveying direction of the positive electrode sheet, and is configured to provide a deactivation agent to the positive electrode sheet to deactivate the positive active material of a part of the positive active material layer of the positive electrode sheet to form a deactivation zone, at least a part of the deactivation zone is located in the bending zone, and at least a part of the deactivation zone is located in the innermost circle of the positive electrode sheet.

9. The winding device according to claim 8, characterized in that The deactivation device is configured to provide a deactivation agent to a side of the positive electrode sheet facing the winding device.

10. The winding device according to claim 8 or 9, characterized in that The deactivation device comprises: A clamping mechanism, used for clamping the positive electrode sheet and providing the deactivating agent to the positive electrode sheet; The driving mechanism is used to drive the clamping mechanism to move synchronously with the positive electrode plate.

11. The winding device according to claim 10, characterized in that The clamping mechanism comprises: Bracket; A first clamping portion and a second clamping portion are disposed on the bracket; and A first driving member, disposed on the bracket, for driving the first clamping portion and the second clamping portion to move closer to or farther from each other, so as to clamp or release the positive electrode sheet; Wherein, at least one of the first clamping portion and the second clamping portion is configured to provide the deactivating agent to the positive electrode sheet.

12. The winding device according to claim 11, characterized in that At least one of the first clamping portion and the second clamping portion is a porous material.

13. The winding device according to claim 11, characterized in that The driving mechanism comprises: A screw rod is arranged along the running direction of the positive electrode sheet, and the screw rod passes through the bracket and is threadedly matched with the bracket; The second driving member is used to drive the screw to rotate so that the bracket moves along the axial direction of the screw.

14. The winding device according to claim 10, characterized in that The deactivation device comprises at least two clamping mechanisms spaced apart along the running direction of the positive electrode sheet, and the driving mechanism is used to drive at least two clamping mechanisms to move synchronously.

15. The winding device according to claim 10, characterized in that The deactivation device also includes: A detection mechanism, used for detecting the position information of the positive electrode plate; A controller is used to control the actions of the clamping mechanism and the driving mechanism according to the position information detected by the detection mechanism.

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