Extrusion equipment, preparation method of electrode diaphragm, battery pole piece, battery and electronic equipment

Abstract

The invention provides extrusion equipment, a preparation method of an electrode diaphragm, a battery pole piece, a battery and electronic equipment. The extrusion equipment comprises a barrel, at least two extrusion assemblies and a temperature adjusting structure. The barrel is provided with a containing cavity. The at least two extrusion assemblies are arranged in the accommodating cavity at intervals; each extrusion assembly comprises a rotating shaft, a thread structure and a kneading structure, and the rotating shaft comprises a first section, a second section and a third section; the first section and the third section are respectively provided with a thread structure, and the second section is provided with a kneading structure. The temperature adjusting structure comprises a first temperature adjusting part, a second temperature adjusting part and a third temperature adjusting part, and the first temperature adjusting part, the second temperature adjusting part and the third temperature adjusting part are arranged at the positions, corresponding to the first section, the second section and the third section, of the barrel correspondingly and used for conducting independent temperature adjusting on the positions, corresponding to the first section, the second section and the third section, of the barrel correspondingly; the temperature requirements of the binder at different positions of the cylinder are met, and the fibration effect of the binder is improved.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to an extrusion device, a method for preparing an electrode membrane, a battery electrode, a battery, and an electronic device. Background Art

[0002] The dry electrode process abandons the use of solvents in the traditional wet electrode manufacturing process, and realizes a fully dry process from dry powder mixing to electrode forming, which can effectively avoid the shortcomings of high energy consumption, environmental pollution and low membrane surface density. The electrode materials of the dry electrode process include active substances, conductive agents and binders. In the dry electrode process, the binder is highly sensitive to temperature, and the mechanical properties of the binder are different at different temperatures. However, in the process of fiberizing the material, the traditional fiberizing equipment has a single form of regulating the cylinder temperature, resulting in insufficient accuracy in regulating the temperature of the material in the cylinder, making it difficult to control the degree of fiberization of the binder, and causing the binder in the produced electrode material mixture to easily have uneven fiberization problems, resulting in low production efficiency. Summary of the Invention

[0003] The present application provides an extrusion device, a method for preparing an electrode membrane, a battery electrode, a battery and an electronic device to solve the problem of insufficient temperature regulation accuracy of a cylinder of a traditional fiberizing device.

[0004] In the first aspect, the present application provides an extrusion device, which includes a cylinder, at least two extrusion assemblies and a temperature control structure. The cylinder is provided with a receiving cavity. At least two extrusion assemblies are arranged at intervals in the receiving cavity along a plane perpendicular to the axial direction; each extrusion assembly includes a rotating shaft, a threaded structure and a kneading structure, and the rotating shaft includes a first segment, a second segment and a third segment arranged in sequence along the axial direction; the first segment and the third segment are respectively provided with the threaded structure, and the second segment is provided with the kneading structure. The temperature control structure includes a first temperature control member, a second temperature control member and a third temperature control member, and the first temperature control member, the second temperature control member and the third temperature control member are respectively provided at positions corresponding to the first segment, the second segment and the third segment of the cylinder, and are used to separately adjust the temperature of the positions of the cylinder corresponding to the first segment, the second segment and the third segment.

[0005] In combination with the first aspect, in certain implementations of the first aspect, the temperature adjustment ranges of the first temperature adjustment component, the second temperature adjustment component, and the third temperature adjustment component are each 20° C.-300° C.

[0006] In combination with the first aspect, in certain implementations of the first aspect, the first temperature regulating component, the second temperature regulating component and the third temperature regulating component each include a heating part and a cooling part, respectively, the heating part includes a heat conductor and a heating coil, the heat conductor is located in the accommodating cavity, the heating coil is used to heat the heat conductor after power is turned on, the cooling part is located in the accommodating cavity, a cooling channel is provided in the cooling part, and the cooling channel is used to accommodate cooling liquid.

[0007] In combination with the first aspect, in certain implementations of the first aspect, the ratio of the axial length of the first segment to the axial length of the rotating shaft is defined as R1, wherein 0.2≤R1≤0.7; the ratio of the axial length of the second segment to the axial length of the rotating shaft is defined as R2, wherein 0<R2≤0.2; the ratio of the axial length of the third segment to the axial length of the rotating shaft is defined as R3, wherein 0.1≤R3≤0.8.

[0008] In combination with the first aspect, in certain implementations of the first aspect, the threaded structure is provided with a spiral protrusion, and the pitch of the spiral protrusion is 5 mm-100 mm.

[0009] In combination with the first aspect, in certain implementations of the first aspect, the lead of the spiral protrusion is 10 mm-200 mm.

[0010] In combination with the first aspect, in certain implementations of the first aspect, the number of the threaded structures of each of the extrusion components is 2-84.

[0011] In combination with the first aspect, in certain implementations of the first aspect, along the arrangement direction of all the extrusion components, the minimum spacing between two corresponding thread structures on two adjacent extrusion components is 0.1 mm-1 mm.

[0012] In combination with the first aspect, in certain implementations of the first aspect, along the radial direction of the rotating shaft, a minimum distance between the thread structure and the inner cavity wall of the accommodating cavity is 0.05 mm-1 mm.

[0013] In combination with the first aspect, in certain implementations of the first aspect, the kneading structure includes a plurality of kneading elements, the plurality of kneading elements are arranged along the axial direction of the rotating shaft, and two adjacent kneading elements are deflected along the circumferential direction of the rotating shaft.

[0014] In combination with the first aspect, in certain implementations of the first aspect, the plurality of kneading elements are arranged in a spiral pattern along the axial direction of the rotating shaft.

[0015] In combination with the first aspect, in certain implementations of the first aspect, the lead of the kneading structure is 5 mm-240 mm.

[0016] In combination with the first aspect, in certain implementations of the first aspect, a deflection angle of two adjacent kneading elements along the circumferential direction of the rotation axis is defined as θ1, wherein 0°<θ1≤90°.

[0017] In combination with the first aspect, in certain implementations of the first aspect, a thickness of the kneading element along the axial direction of the rotating shaft is 5 mm to 20 mm.

[0018] In combination with the first aspect, in certain implementations of the first aspect, the number of the kneading elements in each of the extrusion assemblies is 1-48.

[0019] In combination with the first aspect, in certain implementations of the first aspect, along the arrangement direction of all the extrusion assemblies, a minimum spacing between two corresponding kneading elements on two adjacent extrusion assemblies is 0.1 mm-2 mm.

[0020] In combination with the first aspect, in certain implementations of the first aspect, along the radial direction of the rotating shaft, a minimum distance between the kneading element and the inner wall of the accommodating chamber is 0.1 mm to 3 mm.

[0021] In a second aspect, the present application provides a method for preparing an electrode membrane, the method comprising:

[0022] Mixing the active material, the conductive agent and the binder to obtain an electrode material mixture;

[0023] The electrode material mixture is subjected to a fiberizing treatment by an extrusion device as described above;

[0024] The electrode material mixture after fiberization is subjected to calendering to obtain the electrode membrane.

[0025] In combination with the second aspect, in certain implementations of the second aspect, the temperature of the mixing process of the active material, the conductive agent, and the binder is less than 19°C.

[0026] In combination with the second aspect, in certain implementations of the second aspect, the mass ratio of the active material, the conductive agent, and the binder is (90-99): (0.5-9): (0.5-10).

[0027] In combination with the second aspect, in certain implementations of the second aspect, the temperature of the fiberization treatment is 20°C-300°C.

[0028] In combination with the second aspect, in certain implementations of the second aspect, during the fiberization process, the rotational speed of the rotating shaft of the extrusion device is 20 r / min-1000 r / min.

[0029] In combination with the second aspect, in certain implementations of the second aspect, the temperature of the calendering treatment is 40°C-200°C.

[0030] In combination with the second aspect, in certain implementations of the second aspect, the calendering process includes a first rolling process and a second rolling process, the roll gap spacing of the first rolling process is defined as D1, wherein 1000μm<D1≤5000μm, and the roll gap spacing of the second rolling process is defined as D2, wherein 0μm<D2≤1000μm.

[0031] In combination with the second aspect, in certain implementations of the second aspect, the calendering treatment is performed by differential rolling, and the differential speed ratio of the differential rolling is 1:1-4:1.

[0032] In a second aspect, the present application provides a battery electrode, which includes a current collector and the electrode membrane prepared by any of the preparation methods described above, wherein the electrode membrane is fixed on the current collector.

[0033] In a second aspect, the present application provides a battery, comprising a housing and the battery electrode as described above, wherein the battery electrode is disposed in the housing.

[0034] In a second aspect, the present application provides an electronic device, comprising a functional element and the battery as described above, wherein the battery is used to power the functional element.

[0035] In the extrusion equipment, electrode membrane preparation method, battery electrode, battery and electronic equipment provided by the present application, a first segment, a second segment and a third segment arranged in sequence along the axial direction are provided based on the rotating shaft, a threaded structure is provided on the first segment and the third segment respectively, and a kneading structure is provided on the second segment. The first temperature regulating member, the second temperature regulating member and the third temperature regulating member are respectively provided at positions corresponding to the first segment, the second segment and the third segment of the cylinder, and are respectively used to separately adjust the temperature of the positions of the cylinder corresponding to the first segment, the second segment and the third segment, so that the extrusion equipment can independently adjust the temperature of different positions in the cylinder, improve the accuracy of the temperature regulation of the cylinder, so as to meet the temperature requirements of the binder at different positions of the cylinder, improve the fiberization effect of the binder, and through the joint regulation of the temperature by the first temperature regulating member, the second temperature regulating member and the third temperature regulating member, the temperature regulation efficiency of the material in the cylinder can be improved, the temperature control accuracy of the material can be improved, and the production efficiency of the extrusion equipment can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0037] Figure 1 It is a cross-sectional schematic diagram of the extrusion equipment provided in an embodiment of the present application at one viewing angle.

[0038] Figure 2 It is a schematic structural diagram of the extrusion assembly provided in an embodiment of the present application.

[0039] Figure 3 It is a cross-sectional schematic diagram of the extrusion equipment provided in an embodiment of the present application from another perspective.

[0040] Figure 4 It is a structural schematic diagram of the thread structure provided in an embodiment of the present application.

[0041] Figure 5 yes Figure 2 Cross-sectional view at II in the middle.

[0042] Figure 6 It is a structural schematic diagram of the kneading structure provided in the embodiment of the present application.

[0043] Figure 7 yes Figure 2 Cross-sectional view at II-II.

[0044] Figure 8 This is a flow chart of the method for preparing the electrode membrane provided in the embodiment of the present application.

[0045] Figure 9 Scanning electron microscope image of the electrode membrane provided in the first embodiment of the present application.

[0046] Figure 10 A scanning electron microscope image of the electrode membrane provided in the second embodiment of the present application.

[0047] Figure 11 It is a schematic structural diagram of the battery electrode provided in an embodiment of the present application.

[0048] Explanation of the main reference numerals: extrusion device 100; cylinder 10; accommodating chamber 101; extrusion assembly 20; rotating shaft 21; engaging protrusion 210; first segment 211; second segment 212; third segment 213; threaded structure 22; main body 221; spiral protrusion 222; spiral groove 223; first fixing hole 224; first engaging groove 225; kneading structure 23; kneading element 231; second fixing hole 2311; second engaging groove 2312; temperature adjustment structure 30; First thermostat 31; second thermostat 32; third thermostat 33; heating portion 311; heat conductor 3111; heating coil 3112; cooling portion 312; cooling channel 3121; pitch P1; lead S1; lead S2; minimum spacing C1; minimum spacing C2; minimum spacing C3; minimum spacing C4; deflection angle θ1; thickness T1; axial direction Y; circumferential direction Z; radial direction X; battery electrode 500; current collector 510; electrode diaphragm 520.

[0049] The following specific implementation methods will further illustrate the present application in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0050] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments in this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0051] References herein to "embodiments" or "implementations" mean that a particular feature, structure, or characteristic described in connection with the embodiments or implementations may be included in at least one embodiment of the present application. The appearance of such phrases in various places in the specification does not necessarily refer to the same embodiment, nor do they constitute independent or alternative embodiments that are mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0052] It should be noted that the terms used in the specification, claims, and drawings of this application are intended only to describe specific embodiments and are not intended to limit this application. The terms "first," "second," and so on, used in the specification, claims, and drawings of this application are used to distinguish between different objects, not to describe a specific order.

[0053] Please also refer to Figure 1 and Figure 2 , Figure 1 is a cross-sectional schematic diagram of the extrusion device 100 provided in an embodiment of the present application at a viewing angle, Figure 2This is a schematic diagram of the structure of the extrusion assembly 20 provided in an embodiment of the present application. Extrusion equipment 100 is suitable for use in dry electrode processes. Electrode materials in dry electrode processes include active materials, conductive agents, and binders. Extrusion equipment 100 is used to fiberize the electrode material mixture to fiberize the binder in the electrode material mixture and form a fiber web that encapsulates the active material and conductive agent.

[0054] The extrusion device 100 includes a cylinder 10, at least two extrusion assemblies 20, and a temperature control structure 30. The cylinder 10 is provided with a receiving chamber 101. At least two extrusion assemblies 20 are arranged at intervals in the receiving chamber 101 along a plane perpendicular to the axial direction Y. Each extrusion assembly 20 includes a rotating shaft 21, a threaded structure 22, and a kneading structure 23. The rotating shaft 21 includes a first segment 211, a second segment 212, and a third segment 213 arranged in sequence along the axial direction Y. The first segment 211 and the third segment 213 are respectively provided with a threaded structure 22. The second segment is provided with a kneading structure 23. The temperature control structure 30 includes a first temperature control member 31, a second temperature control member 32, and a third temperature control member 33. The first, second, and third temperature control members 31, 32, and 33 are respectively disposed on the barrel 10 at locations corresponding to the first, second, and third segments 211, 212, and 213, and are used to independently control the temperature of the barrel 10 at the locations corresponding to the first, second, and third segments 211, 212, and 213, respectively. The threaded structure 22 is used to extrude and shear the electrode material mixture. The kneading structure 23 is used to stretch, knead, and shear the electrode material mixture to fiberize the binder. The first temperature regulating component 31, the second temperature regulating component 32 and the third temperature regulating component 33 in the extrusion equipment 100 in the embodiment of the present application can independently adjust the temperature at different positions in the barrel 10, thereby improving the accuracy of the temperature regulation of the barrel 10, so as to meet the temperature requirements of the adhesive at different positions of the barrel 10, improve the fiberization effect of the adhesive, and through the joint regulation of the temperature by the first temperature regulating component 31, the second temperature regulating component 32 and the third temperature regulating component 33, the temperature regulation efficiency of the material in the barrel 10 can be improved, the temperature control accuracy of the material can be improved, and the production efficiency of the extrusion equipment 100 can be improved.

[0055] It should be noted that, in this embodiment, for the convenience of description, Figure 1 、 Figure 2 and Figure 3 For reference, the term "axial direction Y" herein refers to a direction parallel to the central axis of the rotating shaft 21. The term "circumferential direction Z" refers to a direction surrounding the central axis of the rotating shaft 21. The term "radial direction X" refers to a direction parallel to the diameter of the rotating shaft 21. The radial direction X is perpendicular to the axial direction Y.

[0056] When the electrode material mixture enters the accommodating chamber 101, the temperature of the electrode material mixture is the temperature after being processed by the upstream equipment. The temperature of the electrode material mixture is usually different from the temperature of the binder during fiberization. In the embodiment of the present application, the first segment 211 is used to compact the electrode material mixture to increase the filling rate of the electrode material mixture, and the temperature of the electrode material mixture is adjusted by the first temperature regulating member 31. The temperature of the electrode material mixture can be adjusted to the temperature required for the fiberization of the binder, thereby improving the fiberization effect of the binder. The second segment 212 is used to stretch, knead, and shear the electrode material mixture to fiberize the binder.

[0057] When the electrode material mixture is output to the downstream equipment, the temperature of the electrode material mixture needs to match the downstream equipment. In the embodiment of the present application, the third segment 213 is used to transport the fiberized electrode material mixture out of the extrusion device 100 so that the electrode material mixture enters the downstream equipment, and the temperature of the electrode material mixture is adjusted by the third temperature regulating component 33, which can reduce the temperature adjustment step in the downstream process, reduce the process flow, and improve production efficiency.

[0058] In the embodiment of the present application, the temperature range of the first thermostat 31, the second thermostat 32, and the third thermostat 33 is 20°C-300°C. The temperature of the first thermostat 31, the second thermostat 32, and the third thermostat 33 can be 20°C, 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, 160°C, 170°C, 180°C, 190°C, 195°C, 200°C, etc. In some embodiments, the temperature of the first thermostat 31 can be set higher than that of the second thermostat 32 to increase the temperature rise rate of the electrode material mixture at the first segment 211, allowing the electrode material mixture to be heated to the required temperature at the second segment 212 more quickly, thereby shortening the axial length of the first segment 211, improving production efficiency, and reducing production costs.

[0059] Please also refer to Figure 1 and Figure 3 , Figure 3It is a cross-sectional schematic diagram of the extrusion equipment 100 provided in an embodiment of the present application from another perspective. The first temperature regulating component 31, the second temperature regulating component 32 and the third temperature regulating component 33 each include a heating part 311 and a cooling part 312, respectively. The heating part 311 and the cooling part 312 are respectively located in the accommodating chamber 101 to improve the heat exchange efficiency between the heating part 311, the cooling part 312 and the material in the barrel 10, and to improve the accuracy of temperature control of the material. The heating part 311 is used to heat the electrode material mixture in the accommodating chamber 101. The cooling part 312 is used to cool the electrode material mixture in the accommodating chamber 101. In this way, by jointly regulating the temperature in the accommodating chamber 101 through the heating part 311 and the cooling part 312, the accuracy of temperature control in the accommodating chamber 101 can be improved, the time required for temperature regulation can be reduced, and the regulation efficiency can be improved.

[0060] The heating unit 311 includes a heat conductor 3111 and a heating coil 3112. The heat conductor 3111 is located within the accommodating chamber 101. The heating coil 3112 is used to heat the heat conductor 3111 when powered. The heating coil 3112 is wound around the outer circumference of the heat conductor 3111. After current passes through the heating coil 3112, the heating coil 3112 heats the heat conductor 3111 through electromagnetic heating. The heating unit 311 heats the accommodating chamber 101 through electromagnetic heating, which can improve heating efficiency and reduce temperature adjustment time.

[0061] A cooling channel 3121 is provided in the cooling portion 312. The cooling channel 3121 is used to accommodate a coolant. The coolant is used to absorb the heat in the accommodating chamber 101 to achieve cooling of the accommodating chamber 101. The coolant may be cooling water, cooling oil, refrigerant, or the like. In some embodiments, the extrusion device 100 further includes a circulating pump and a radiator connected to the cooling channel 3121. The circulating pump is used to circulate the coolant in the cooling channel 3121, and the radiator is used to dissipate heat from the coolant flowing out of the accommodating chamber 101.

[0062] In some embodiments, the extrusion apparatus 100 further includes a temperature sensor. The temperature sensor is used to detect the temperature within the accommodating chamber 101 and, in conjunction with the temperature control structure 30, regulate the temperature within the accommodating chamber 101. At least three temperature sensors may be provided. At least one temperature sensor is disposed on the barrel 10 at positions corresponding to the first segment 211, the second segment 212, and the third segment 213.

[0063] See also Figure 2In some embodiments, along the axial direction Y, the ratio of the axial length of the first segment 211 to the axial length of the rotating shaft 21 is defined as R1, where 0.2≤R1≤0.7. For example, the ratio R1 can be 0.2, 0.3, 0.4, 0.5, 0.7, etc. Along the axial direction Y, the ratio of the axial length of the second segment 212 to the axial length of the rotating shaft 21 is defined as R2, where 0<R2≤0.2. For example, the ratio R2 can be 0.05, 0.1, 0.15, 0.2, etc. The ratio of the axial length of the third segment 213 to the axial length of the rotating shaft 21 is defined as R3, where 0.1≤R3≤0.8. For example, the ratio R3 can be 0.1, 0.2, 0.3, 0.4, 0.5, 0.7, 0.8, etc. In some embodiments, the axial length of the first segment 211 may be greater than or equal to that of the third segment 213 . In this way, the axial length of the third segment 213 may be shortened, making the extrusion device 100 miniaturized.

[0064] In this embodiment, the number of extrusion assemblies 20 is set to two to simplify the structure of the extrusion device 100 and reduce manufacturing costs. In some embodiments, the number of extrusion assemblies 20 can be set to more than two, and the two or more extrusion assemblies 20 are arranged at intervals along a plane perpendicular to the axial direction Y. The number of extrusion assemblies 20 can be specifically set according to actual needs. For example, the number of extrusion assemblies 20 can be set to three, four, etc.

[0065] Please also refer to Figure 1 、 Figure 2 、 Figure 4 and Figure 5 , Figure 4 It is a structural diagram of the thread structure 22 provided in an embodiment of the present application. Figure 5 yes Figure 2 Cross-sectional view at point II in the middle. The threaded structure 22 is relatively fixed to the rotating shaft 21 along the circumferential direction Z. The threaded structure 22 includes a main body 221 and a spiral protrusion 222 provided on the main body 221. A spiral groove 223 is formed between the spiral protrusion 222 and the main body 221. The main body 221 is provided with a first fixing hole 224 along the axial direction Y. The rotating shaft 21 is passed through the first fixing hole 224. A first clamping groove 225 is provided on one of the inner side wall of the first fixing hole 224 and the outer side wall of the rotating shaft 21, and a clamping protrusion 210 is provided on the other of the inner side wall of the first fixing hole 224 and the outer side wall of the rotating shaft 21. The clamping protrusion 210 is used to be accommodated in the first clamping groove 225, and the first clamping groove 225 is used to limit the rotation of the clamping protrusion 210 along the circumferential direction Z, so that the threaded structure 22 is fixed relative to the rotating shaft 21 along the circumferential direction Z. When the rotating shaft 21 drives the threaded structure 22 to rotate, the spiral protrusion 222 squeezes the material and pushes the material to move along the spiral groove 223 .

[0066] The pitch of the spiral protrusion 222 is defined as P1, and the pitch P1 ranges from 5 mm to 100 mm. This ensures that when the spiral protrusion 222 compresses the electrode material mixture to propel it in the axial direction Y, the electrode material mixture remains in the accommodating chamber 101 for a sufficient time, allowing the first and third temperature regulating members 31 and 33 to accurately regulate the temperature of the electrode material mixture and causing the electrode material mixture to be "compressed" and "folded" within the spiral groove 223, ensuring that the filling rate of the electrode material mixture in the accommodating chamber 101 meets the requirements. The pitch P1 of the spiral protrusion 222 can be set based on actual needs and is not specifically limited in this application. Illustratively, the pitch P1 can be 5mm, 6mm, 8mm, 10mm, 12mm, 15mm, 20mm, 25mm, 30mm, 35mm, 40mm, 45mm, 50mm, 55mm, 60mm, 65mm, 70mm, 75mm, 80mm, 85mm, 90mm, 95mm, 100mm, etc.

[0067] In some embodiments, the thread structure 22 can be configured as a multi-thread structure. The main body 221 is provided with multiple spiral protrusions 222, which are spaced apart along the circumferential direction Z. This allows the multiple spiral protrusions 222 to share the reaction force of the electrode material mixture, thereby reducing the reaction force borne by each spiral protrusion 222 and improving the load-bearing capacity of the thread structure 22. Furthermore, it increases the speed at which the thread structure 22 conveys the electrode material mixture, thereby improving production efficiency. The number of spiral protrusions 222 can be set based on actual needs and is not specifically limited in this application. For example, the number of spiral protrusions 222 can be one, two, three, or four. The lead of the spiral protrusion 222 is defined as S1, which is the product of the pitch P1 and the number of thread structures 22. The lead S1 of the spiral protrusion 222 ranges from 10 mm to 200 mm. The lead S1 of the thread structure 22 can be set based on actual needs and is not specifically limited in this application. Exemplarily, the lead S1 can be 10mm, 15mm, 20mm, 25mm, 30mm, 35mm, 40mm, 45mm, 50mm, 55mm, 60mm, 65mm, 70mm, 75mm, 80mm, 85mm, 90mm, 95mm, 100mm, 110mm, 120mm, 130mm, 140mm, 150mm, 160mm, 170mm, 180mm, 190mm, 200mm, etc.

[0068] The number of thread structures 22 in each extrusion assembly 20 ranges from 2 to 84. The number of thread structures 22 in each extrusion assembly 20 can be set according to actual needs and is not specifically limited in this application. For example, the number of thread structures 22 in each extrusion assembly 20 can be 2, 3, 4, 5, 10, 15, 20, 24, 25, 26, 27, 30, 35, 36, 40, 42, 45, 50, 55, 60, 65, 70, 75, 80, 81, 82, 83, 84, etc. The number of thread structures 22 in the first segment 211 and the third segment 213 can be set to one or more, respectively.

[0069] Along the arrangement direction of all the extrusion assemblies 20, in the two corresponding thread structures 22 on two adjacent extrusion assemblies 20, the spiral protrusion 222 of one thread structure 22 is located in the spiral groove 223 of the other thread structure 22, and the two thread structures 22 are spaced apart from each other to avoid structural interference between the thread structures 22, which is conducive to facilitating the disassembly and assembly of the thread structures 22 and ensuring the continuous transportation of materials in the accommodating chamber 101. Along the arrangement direction of all the extrusion assemblies 20, the minimum spacing between the two corresponding thread structures 22 on two adjacent extrusion assemblies 20 is defined as C1, and the minimum spacing C1 is 0.1mm-1mm. Among them, the minimum spacing C1 can be the spacing between the farthest point of the spiral protrusion 222 in one of the extrusion assemblies 20 relative to the rotating shaft 21 and the closest point of the spiral groove 223 in the other extrusion assembly 20 relative to the rotating shaft 21. The minimum spacing C1 can be specifically set according to actual needs and is not specifically limited in this application. Illustratively, the minimum spacing C1 may be 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, etc.

[0070] Along the radial direction X of the rotating shaft 21, the threaded structure 22 is spaced apart from the inner wall of the accommodating chamber 101. On the one hand, this can avoid structural interference between the threaded structure 22 and the cylinder 10, prevent frictional heat generation and the generation of foreign matter. On the other hand, it is convenient for the disassembly and assembly of the threaded structure 22. On the other hand, it is conducive to the continuous transportation and folding of materials in the accommodating chamber 101, reducing the retention of materials in the accommodating chamber 101. Along the radial direction X of the rotating shaft 21, the minimum spacing between the threaded structure 22 and the inner wall of the accommodating chamber 101 is defined as C2, and the minimum spacing C2 is 0.05mm-1mm. The minimum spacing C2 can be specifically set according to actual needs and is not specifically limited in this application. For example, the minimum spacing C2 can be 0.05mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, etc.

[0071] The pitch P1, lead S1, minimum pitch C1, and minimum pitch C2 of the different thread structures 22 in each extrusion assembly 20 can be set to be the same or different, and the spiral directions of the spiral protrusions 222 in different thread structures 22 can be set to be the same or different. In this embodiment, the thread structure 22 and the rotating shaft 21 are detachable to facilitate replacement and maintenance of the thread structure 22 in the extrusion assembly 20. In this way, compared to the solution where the thread structure 22 and the rotating shaft 21 are not detachable, the extrusion device 100 in the embodiment of the present application can specifically set the specific parameters of the thread structure 22 according to factors such as the required residence time of the electrode material mixture in the accommodating chamber 101, the filling rate, the heat exchange efficiency between the electrode material mixture and the temperature regulating structure 30, the type and mass ratio of each component in the electrode material mixture, and the fiberization conditions of the binder. This is conducive to improving the scope of use of the extrusion device 100 and improving the adaptability of the extrusion device 100 to different production requirements. By making the extrusion assembly 20 modular, the extrusion assembly 20 can adjust the relevant parameters of the thread structure 22 according to process requirements, thereby improving the applicability of the extrusion device 100.

[0072] Please also refer to Figure 1 、 Figure 2 、 Figure 6 and Figure 7 , Figure 6 is a structural diagram of the kneading structure 23 provided in the embodiment of the present application, Figure 7 yes Figure 2 Cross-sectional view taken at II-II in FIG. The kneading structure 23 includes a plurality of kneading elements 231. The plurality of kneading elements 231 are arranged along the axial direction Y of the rotating shaft 21. The kneading elements 231 are provided with a second fixing hole 2311 along the axial direction Y. The rotating shaft 21 is inserted into the second fixing hole 2311. A second retaining groove 2312 is provided on one of the inner sidewall of the second fixing hole 2311 and the outer sidewall of the rotating shaft 21. A locking protrusion 210 is provided on the other of the inner sidewall of the second fixing hole 2311 and the outer sidewall of the rotating shaft 21. The locking protrusion 210 is configured to be received in the second retaining groove 2312. The second retaining groove 2312 is configured to limit the rotation of the retaining protrusion 210 along the circumferential direction Z, thereby securing the kneading elements 231 relative to the rotating shaft 21 along the circumferential direction Z. When the rotating shaft 21 drives the kneading element 231 to rotate, the kneading element 231 extrude, stretch and shear the electrode material mixture, so that the electrode material mixture is fibrillated at the position of the second segment 212. The kneading element 231 is used to provide the binder with the shear force required in the fibrillation process, so that the binder forms fiber filaments, and the fiber filaments are interlaced to form a fiber mesh, and the active material and the conductive agent are coated in the fiber mesh.

[0073] The kneading element 231 is generally constructed as an elliptical sheet-like structure. It has a major axis and a minor axis perpendicular to the major axis. The kneading element 231 extends longer along the major axis than along the minor axis. A relief portion 232 is provided at the end of the kneading element 231 along the major axis. This relief space is formed between the relief portion 232 and the wall of the accommodating chamber 101. This relief space helps increase the dwell time of the material at the kneading element 231. When the kneading element 231 rotates relative to the barrel 10, the kneading element 231 causes the material within the relief space to tumble, squeeze, and knead, thereby enhancing the fiberization effect of the binder.

[0074] Adjacent kneading elements 231 are arranged in a deflected manner along the circumferential direction Z of the rotating shaft 21. The multiple kneading elements 231 in the kneading structure 23 can be arranged regularly or irregularly. In this embodiment, the multiple kneading elements 231 in the kneading structure 23 are arranged in a deflected manner along the axial direction Y of the rotating shaft 21, and the multiple kneading elements 231 are arranged in a spiral. The lead of the kneading structure 23 is defined as S2, and the lead S2 ranges from 5 mm to 240 mm. The lead S2 of the kneading structure 23 is the sum of the thicknesses of the multiple kneading elements 231 along the axial direction Y. The lead S2 of the kneading structure 23 can be specifically set according to actual needs and is not specifically limited in this application. Illustratively, the lead S2 of the kneading structure 23 may be 5 mm, 10 mm, 15 mm, 20 mm, 25 mm, 30 mm, 35 mm, 40 mm, 45 mm, 50 mm, 55 mm, 60 mm, 65 mm, 70 mm, 75 mm, 80 mm, 85 mm, 90 mm, 95 mm, 100 mm, 110 mm, 120 mm, 130 mm, 140 mm, 150 mm, 160 mm, 170 mm, 180 mm, 190 mm, 200 mm, 210 mm, 220 mm, 230 mm, 240 mm, etc.

[0075] The deflection angle between two adjacent kneading elements 231 along the circumferential direction of the rotation axis is defined as θ1, where 0° < θ1 ≤ 90°. The specific value of the deflection angle θ1 can be set according to actual needs and is not specifically limited in this application. For example, the deflection angle θ1 can be 10°, 20°, 30°, 35°, 40°, 45°, 50°, 55°, 60°, 65°, 70°, 75°, 80°, 85°, 90°, etc.

[0076] The thickness of the kneading elements 231 along the axial direction Y of the rotating shaft 21 is defined as T1, and this thickness ranges from 5 mm to 20 mm. This ensures that a sufficient number of kneading elements 231 are provided to fully knead the electrode material mixture, improving the kneading and shearing efficiency of the electrode material mixture in the second segment 212 and enhancing the fiberization of the binder. This prevents kneading elements 231 from being too thin, resulting in insufficient extrusion and pushing capability, and from being too thick, resulting in inefficient kneading. The thickness T1 can be set based on practical needs and is not specifically limited in this application. Exemplarily, the thickness T1 can be 5mm, 5.2mm, 5.4mm, 5.5mm, 5.6mm, 5.8mm, 6mm, 6.2mm, 6.4mm, 6.5mm, 6.6mm, 6.8mm, 7mm, 7.2mm, 7.4mm, 7.5mm, 7.6mm, 7.8mm, 8mm, 9mm, 10mm, 11mm, 12mm, 13mm, 14mm, 15mm, 16mm, 17mm, 18mm, 19mm, 20mm, etc.

[0077] The number of kneading elements 231 in each extrusion assembly 20 ranges from 1 to 48. The number of kneading elements 231 in each extrusion assembly 20 can be set according to actual needs and is not specifically limited in this application. For example, the number of kneading elements 231 in each extrusion assembly 20 can be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 24, 25, 26, 27, 30, 35, 36, 40, 42, 45, 48, etc.

[0078] Along the arrangement direction of all extrusion assemblies 20, the minimum spacing between corresponding kneading elements 231 on two adjacent extrusion assemblies 20 is defined as C3. This minimum spacing C3 ranges from 0.1 mm to 2 mm. This prevents structural interference between corresponding kneading elements 231, prevents the generation of foreign matter, facilitates assembly and disassembly of the kneading elements 231, and allows the material to be extruded and sheared between the two kneading elements 231, thereby improving the fiberization effect of the binder. The minimum spacing C3 can be defined as the distance between the farthest point of a kneading element 231 in one extrusion assembly 20 relative to the rotation axis 21 and the closest point of a kneading element 231 in another extrusion assembly 20 relative to the rotation axis 21. The minimum spacing C3 can be defined as the distance between corresponding kneading elements 231 on two adjacent extrusion assemblies 20 when the two kneading elements 231 are in a vertical position (i.e., the long axes of the two kneading elements 231 are perpendicular to each other). The minimum spacing C3 can be set based on actual needs and is not specifically limited in this application. Exemplarily, the minimum spacing C3 may be 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm, 2 mm, etc.

[0079] Along the radial direction X of the rotating shaft 21, the kneading element 231 is spaced apart from the inner wall of the accommodating chamber 101 to prevent structural interference between the kneading element 231 and the barrel 10 and facilitate assembly and removal of the kneading element 231. The minimum spacing C4 between the kneading element 231 and the inner wall of the accommodating chamber 101 along the radial direction of the rotating shaft is defined as 0.1 mm to 3 mm. This prevents structural interference between the kneading element 231 and the barrel 10, preventing frictional heat generation and the generation of foreign matter. It also facilitates assembly and removal of the kneading element 231 and further facilitates material transport along the axial direction Y at the second segment 212, preventing material from being retained at the second segment 212. The minimum spacing C4 can be set based on practical needs and is not specifically defined in this application. Exemplarily, the minimum spacing C4 can be 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm, 2mm, 2.1mm, 2.2mm, 2.3mm, 2.4mm, 2.5mm, 2.6mm, 2.7mm, 2.8mm, 2.9mm, 3mm, etc.

[0080] The kneading element 231 is detachably connected to the rotating shaft 21 to facilitate replacement and maintenance of the kneading element 231 within the extrusion assembly 20. Compared to solutions in which the kneading element 231 and the rotating shaft 21 are inseparable, the extrusion apparatus 100 in the present embodiment can replace the kneading element 231 according to different production requirements. The modular design of the extrusion assembly 20 allows the parameters of the kneading element 231 to be adjusted according to process requirements, thereby expanding the applicability of the extrusion apparatus 100.

[0081] See also Figure 8 , Figure 8 This is a flow chart of a method for preparing an electrode membrane provided in an embodiment of the present application. The electrode membrane is made by a dry electrode process. The electrode materials in the electrode membrane include an active substance, a conductive agent, and a binder. The active substance can be a positive electrode active material or a negative electrode active material. Positive electrode active materials include but are not limited to lithium iron phosphate (LFP), nickel-cobalt-manganese (NCM), lithium cobalt oxide (LCO), and sodium ferric pyrophosphate (NFPP). Negative electrode active materials include but are not limited to natural graphite, artificial graphite, and silicon carbon. Conductive agents include but are not limited to acetylene black, carbon nanotubes (CNT), carbon nanofibers, activated carbon, graphene, and Ketjen black. Binders include but are not limited to polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), and ultra-high molecular weight polyethylene (UPE).

[0082] The mass ratio of the active material, conductive agent, and binder is (90-99): (0.5-9): (0.5-10). The mass ratio of the active material, conductive agent, and binder can be specifically set according to actual needs and is not specifically limited in this application. For example, the mass ratio of the active material, conductive agent, and binder can be 97:1:2, 98:1:1, etc.

[0083] The preparation method of the electrode membrane includes:

[0084] S410, mixing the active material, the conductive agent and the binder to obtain an electrode material mixture.

[0085] The mixing process can be carried out by a mixing device, including but not limited to a high-speed mixer, a fluidized bed, a ball mill, and a coating machine.

[0086] The mixing process of the active material, the conductive agent, and the binder may include a first mixing process and a second mixing process. The first mixing process is used to uniformly mix the active material and the conductive agent to obtain a first mixture. The second mixing process is used to uniformly mix the first mixture and the binder.

[0087] The temperature of the mixing process of the active material, the conductive agent, and the binder is less than 19° C. In some embodiments, the active material may be subjected to a low-temperature treatment before the first mixing process, so that the active material can offset the temperature rise during the first mixing process, thereby preventing the temperature of the active material from being higher than the phase change temperature of the binder during the friction process, thereby preventing the active material from transferring the temperature to the binder, causing the binder to prematurely become fibrotic due to the temperature being higher than the phase change temperature, and preventing the binder from agglomerating the active material and the conductive agent into lumps, so that the binder can maintain a particle state during the mixing process, thereby allowing the active material, the conductive agent, and the binder to be uniformly mixed in a particle state, thereby improving the mixing uniformity of the electrode material. In some embodiments, the binder can be subjected to low-temperature treatment before the second mixing treatment to avoid the temperature of the binder during the stirring process being higher than the phase change temperature of the binder, so that the binder always remains in a triclinic crystal state during the stirring process, and the crystal structure of the binder is avoided from being transformed into a hexagonal crystal, and the binder is avoided from being prematurely fiberized during the second mixing treatment, thereby avoiding agglomeration problems in the electrode material, and allowing the active material, conductive agent and binder to be uniformly mixed in a particle state during the second mixing treatment, thereby improving the mixing uniformity of the active material, conductive agent and binder in the electrode material.

[0088] S420, the electrode material mixture is subjected to fiberization treatment by extrusion equipment.

[0089] Wherein, the temperature of the fiberization treatment is 20 ℃ -300 ℃. In this way, on the one hand, the binder can be fully fiberized during the fiberization treatment to form a uniformly distributed fiber web, avoiding the problem of insufficient fiberization of the binder due to insufficient temperature and excessive fiberization of the binder due to excessive temperature. Exemplarily, the heating temperature of the fiberization treatment can be 20 ℃, 25 ℃, 30 ℃, 40 ℃, 50 ℃, 60 ℃, 70 ℃, 80 ℃, 90 ℃, 100 ℃, 110 ℃, 120 ℃, 130 ℃, 140 ℃, 150 ℃, 160 ℃, 170 ℃, 180 ℃, 190 ℃, 195 ℃, 200 ℃, 210 ℃, 220 ℃, 230 ℃, 240 ℃, 250 ℃, 260 ℃, 270 ℃, 280 ℃, 290 ℃, 300 ℃, etc.

[0090] During the fiberization process, the rotational speed of the rotating shaft 21 of the extrusion device 100 is 20 rpm to 1000 rpm. This ensures that the conveying speed of the electrode material mixture in the barrel 10 meets production requirements, preventing the electrode material mixture from excessively staying in the barrel 10, which could lead to excessive fiberization of the binder and reduced production speed. Furthermore, it prevents excessive rotational speed of the rotating shaft 21, which could lead to insufficient residence time of the electrode material mixture in the barrel 10 and insufficient fiberization of the binder. The rotational speed of the rotating shaft 21 can be set according to actual needs and is not specifically limited in this application. Illustratively, the rotational speed of the rotating shaft 21 can be 20r / min, 30r / min, 40r / min, 50r / min, 60r / min, 70r / min, 80r / min, 100r / min, 110r / min, 120r / min, 130r / min, 140r / min, 150r / min, 200r / min, 300r / min, 400r / min, 500r / min, 600r / min, 700r / min, 800r / min, 900r / min, 1000r / min, etc.

[0091] S430, rolling the electrode material mixture after the fiberization treatment to obtain an electrode membrane.

[0092] The heating temperature of the calendering treatment is 40°C-200°C. In this way, on the one hand, the binder can be fully fiberized during the calendering treatment to form a uniformly distributed fiber web, avoiding the problem of insufficient fiberization of the binder due to insufficient temperature, and avoiding the problem of excessive fiberization of the binder due to excessive temperature. Among them, the heating temperature of the calendering treatment can be specifically set according to actual needs and is not specifically limited in this application. For example, the heating temperature of the calendering treatment can be 40°C, 50°C, 60°C, 70°C, 80°C, 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, 160°C, 170°C, 180°C, 190°C, 195°C, 200°C, etc.

[0093] The calendering process includes a first rolling process and a second rolling process. The roll gap spacing of the first rolling process is defined as D1, wherein 1000μm<D1≤5000μm. The roll gap spacing D1 of the first rolling process can be specifically set according to actual needs and is not specifically limited in this application. For example, the roll gap spacing D1 of the first rolling process can be 1100μm, 1200μm, 1500μm, 2000μm, 2500μm, 3000μm, 3500μm, 4000μm, 4500μm, 5000μm, etc.

[0094] The roller gap distance of the second roller pressing process is defined as D2, wherein 0 μm<D2≤1000 μm. The roller gap distance D2 of the second roller pressing process can be specifically set according to actual needs and is not specifically limited in this application. For example, the roll gap distance D2 of the second rolling treatment can be 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, 110 μm, 120 μm, 130 μm, 140 μm, 150 μm, 160 μm, 170 μm, 180 μm. m, 190μm, 200μm, 250μm, 300μm, 350μm, 400μm, 450μm, 500μm, 550μm, 600μm, 650μm, 700μm, 750μm, 800μm, 850μm, 900μm, 950μm, 1000μm.

[0095] The calendering treatment is carried out by differential rolling. The differential speed ratio of differential rolling is 1:1-4:1. In the differential rolling treatment, the rotation speeds of the two paired rollers are different, so that the linear speeds on both sides of the electrode material mixture located between the roller gaps of the two rollers are different, so that the rollers shear the electrode material mixture while squeezing the electrode material mixture, thereby causing the binder to undergo secondary fiberization, so that the surface of the electrode membrane after calendering is smooth and wrinkle-free, and the fiber web formed by the binder can bond the active material to form a self-supporting film, so that the tensile strength and elongation of the electrode membrane meet the winding requirements. The differential speed ratio of differential rolling can be specifically set according to actual needs and is not specifically limited in this application. For example, the differential speed ratio of differential rolling can be 1:1, 1.5:1, 2:1, 2.5:1, 3:1, 3.5:1, 4:1. Among them, the calendering treatment can include multiple differential rolling. The differential speed ratios between different differential rolling times can be set to be the same or different.

[0096] See also Figure 9 , Figure 9 This is a scanning electron microscope image of the electrode membrane provided in the first embodiment of the present application. In the first embodiment of the present application, the mass ratio of the active material, the conductive agent, and the binder in the electrode membrane is 97:1:2. The active material is configured as a negative electrode active material, and the active material is specifically configured as graphite. The conductive agent is configured as carbon black (Super P, SP). The binder is configured as polytetrafluoroethylene (PTFE). The preparation method of the electrode membrane in the first embodiment includes:

[0097] Mixing graphite, carbon black and polytetrafluoroethylene to obtain an electrode material mixture;

[0098] The electrode material mixture is subjected to fiberization treatment by passing it through an extrusion device;

[0099] The electrode material mixture after fiberization is subjected to calendering treatment to obtain an electrode membrane.

[0100] During the mixing process, the temperature in the mixing chamber of the mixing device is controlled at 10° C., and the mixing device adopts a high-speed mixer.

[0101] The fiberization process is performed using the extrusion device 100 described in any of the above embodiments. The rotation speed of the rotating shaft 21 is 50 r / min. The adjustment temperature of the first temperature control element 31 is set to 120°C, the adjustment temperature of the second temperature control element 32 is set to 100°C, and the adjustment temperature of the third temperature control element 33 is set to 80°C. Three first-type thread structures, seven second-type thread structures, and seven third-type thread structures are sequentially arranged in the axial direction Y in the first segment 211. Two second-type thread structures and eight third-type thread structures are sequentially arranged in the axial direction Y in the third segment 213. The pitch P1 of the first thread structure is 30 mm, and the lead S1 is 60 mm. The pitch P1 of the second thread structure is 24 mm, and the lead S1 is 48 mm. The pitch P1 of the third thread structure is 16 mm, and the lead S1 is 32 mm. The minimum pitch C1 of the first, second, and third thread structures is 0.8 mm, and the minimum pitch C2 is 0.5 mm. The second segment 212 is provided with one first kneading structure and one second kneading structure, arranged in sequence along the axial direction Y. In the first kneading structure, the kneading elements 231 have a deflection angle θ1 of 45°, a thickness T1 of 8 mm, and a number of five kneading elements 231. The lead S2 of the first kneading structure is 40 mm. In the second kneading structure, the kneading elements 231 have a deflection angle θ1 of 30°, a thickness T1 of 5 mm, and a number of six kneading elements 231. The lead S2 of the first kneading structure is 30 mm. The minimum spacing C3 of both the first and second kneading structures is 1.5 mm, and the minimum spacing C4 of both is 1 mm.

[0102] The first roll pressing process was performed at a heating temperature of 80°C and a differential speed ratio of 3:1. The first roll pressing process was performed three times, with the roll gap distances D1 of 5000 μm, 2500 μm, and 1500 μm, respectively. The second roll pressing process was performed at a heating temperature of 120°C and a differential speed ratio of 1.25:1. The second roll pressing process was performed four times, with the roll gap distances D2 of 700 μm, 500 μm, 300 μm, and 150 μm, respectively.

[0103] The thickness of the electrode membrane prepared by the preparation method in the first embodiment of the present application is about 170 μm. Figure 9It can be seen that in the electrode membrane prepared by the preparation method of the electrode membrane provided in the embodiment of the present application, the particles of each component are evenly mixed together, so that the electrode membrane has good flexibility and toughness.

[0104] See also Figure 10 , Figure 10 This is a scanning electron microscope image of the electrode membrane provided in the second embodiment of the present application. In the second embodiment of the present application, the mass ratio of the active material, the conductive agent, and the binder in the electrode membrane is 97:1:2. The active material is configured as a positive electrode active material, and the active material is specifically configured as a single crystal ternary material (NCM). The conductive agent is configured as carbon black (Super P, SP). The binder is configured as polytetrafluoroethylene (PTFE). The preparation method of the electrode membrane in the first embodiment includes:

[0105] The single crystal ternary metal, carbon black and polytetrafluoroethylene are mixed to obtain an electrode material mixture;

[0106] The electrode material mixture is subjected to fiberization treatment by passing it through an extrusion device;

[0107] The electrode material mixture after fiberization is subjected to calendering treatment to obtain an electrode membrane.

[0108] During the mixing process, the temperature in the mixing chamber of the mixing device is controlled at 10° C., and the mixing device adopts a high-speed mixer.

[0109] The fiberization process is performed using the extrusion device 100 described in any of the above embodiments. The rotation speed of the rotating shaft 21 is 50 r / min. The adjustment temperature of the first temperature control element 31 is set to 80°C, the adjustment temperature of the second temperature control element 32 is set to 80°C, and the adjustment temperature of the third temperature control element 33 is set to 80°C. Five first-type thread structures and eight second-type thread structures are sequentially arranged in the axial direction Y in the first segment 211. Fourteen third-type thread structures are sequentially arranged in the axial direction Y in the third segment 213. The pitch P1 of the first thread structure is 30 mm, and the lead S1 is 60 mm. The pitch P1 of the second thread structure is 24 mm, and the lead S1 is 48 mm. The pitch P1 of the third thread structure is 16 mm, and the lead S1 is 32 mm. The minimum pitch C1 of the first, second, and third thread structures is 0.8 mm, and the minimum pitch C2 of the first, second, and third thread structures is 0.5 mm. The second segment 212 is sequentially arranged in the axial direction Y with one third-type kneading structure. In the third kneading structure, the deflection angle θ1 of the kneading elements 231 is 45°, the thickness T1 of the kneading elements 231 is 6.4 mm, the number of kneading elements 231 is 5, and the lead S2 of the third kneading structure is 32 mm. The minimum pitch C3 of the third kneading structure is 1.5 mm, and the minimum pitch C4 is 1.2 mm.

[0110] The first roll pressing process was performed at a heating temperature of 80°C and a differential speed ratio of 3:1. The first roll pressing process was performed three times, with the roll gap distances D1 of 5000 μm, 2500 μm, and 1500 μm, respectively. The second roll pressing process was performed at a heating temperature of 120°C and a differential speed ratio of 1.2:1, respectively. The second roll pressing process was performed four times, with the roll gap distances D2 of 700 μm, 500 μm, 300 μm, and 150 μm, respectively.

[0111] The thickness of the electrode membrane prepared by the preparation method in the first embodiment of the present application is about 170 μm. Figure 10 It can be seen that in the electrode membrane prepared by the preparation method of the electrode membrane provided in the embodiment of the present application, the particles of each component are evenly mixed together, so that the surface of the electrode membrane is smooth and wrinkle-free, and the electrode membrane has the ability to be rolled up.

[0112] See also Figure 11 , Figure 11 : is a schematic structural diagram of a battery electrode 500 provided in an embodiment of the present application. An embodiment of the present application also provides a battery electrode 500. The battery electrode 500 includes a current collector 510 and an electrode membrane 520 prepared by the preparation method in any of the above embodiments. The electrode membrane 520 is fixed on the current collector 510. In some embodiments, the electrode membrane 520 can be provided as a single layer, and the electrode membrane 520 is provided on one side surface of the current collector 510. In some embodiments, the electrode membrane 520 can be provided as two layers, and the two layers of electrode membrane 520 are provided on the opposite sides of the current collector 510.

[0113] The present application also provides a battery. The battery includes a housing and a battery electrode 500 as described in any of the above embodiments. The battery electrode 500 is disposed within the housing. The battery can be configured as a cylindrical battery, a prismatic battery, a soft-pack battery, or the like.

[0114] The present application also provides an electronic device in accordance with an embodiment of the present invention. The electronic device includes a functional element and a battery as described in the above embodiment. The battery is used to power the functional element. The electronic device can be configured as a car, a mobile phone, a laptop computer, a mobile power bank, an energy storage power supply, or the like. For example, the electronic device can be configured as a car, the functional element can be configured as an electric motor or an onboard computer in the car, and the battery can be configured as the vehicle's power battery.

[0115] The above are only specific embodiments of the present application, but the scope of protection of the present application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and such modifications or substitutions should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. An extrusion device (100), characterized in that include: The cylinder (10) is provided with a receiving cavity (101); At least two extrusion assemblies (20), at least two of the extrusion assemblies (20) are spaced apart in a plane perpendicular to the axial direction (Y) in the accommodating cavity (101); each of the extrusion assemblies (20) comprises a rotating shaft (21), a threaded structure (22), and a kneading structure (23); the rotating shaft (21) comprises a first segment (211), a second segment (212), and a third segment (213) sequentially arranged along the axial direction (Y); the threaded structure (22) is respectively provided on the first segment (211) and the third segment (213), and the kneading structure (23) is provided on the second segment (212); The temperature regulating structure (30) comprises a first temperature regulating element (31), a second temperature regulating element (32) and a third temperature regulating element (33). The first temperature regulating element (31), the second temperature regulating element (32) and the third temperature regulating element (33) are respectively arranged at positions of the barrel (10) corresponding to the first segment (211), the second segment (212) and the third segment (213), and are respectively used to separately regulate the temperatures of the positions of the barrel (10) corresponding to the first segment (211), the second segment (212) and the third segment (213).

2. The extrusion device (100) according to claim 1, characterized in that The temperature adjustment ranges of the first temperature adjustment component (31), the second temperature adjustment component (32) and the third temperature adjustment component (33) are respectively 20°C-300°C.

3. The extrusion device (100) according to claim 1 or 2, characterized in that The first temperature regulating component (31), the second temperature regulating component (32) and the third temperature regulating component (33) respectively include a heating part (311) and a cooling part (312); the heating part (311) includes a heat conductor (3111) and a heating coil (3112); the heat conductor (3111) is located in the accommodating cavity (101); the heating coil (3112) is used to heat the heat conductor (3111) after power is turned on; the cooling part (312) is located in the accommodating cavity (101); a cooling channel (3121) is provided in the cooling part (312); and the cooling channel (3121) is used to accommodate a cooling liquid.

4. The extrusion device (100) according to claim 1, characterized in that The ratio of the axial length of the first segment (211) to the axial length of the rotating shaft (21) is defined as R1, wherein 0.2≤R1≤0.7; the ratio of the axial length of the second segment (212) to the axial length of the rotating shaft (21) is defined as R2, wherein 0<R2≤0.2; and the ratio of the axial length of the third segment (213) to the axial length of the rotating shaft (21) is defined as R3, wherein 0.1≤R3≤0.

8.

5. The extrusion device (100) according to claim 1, characterized in that The thread structure (22) is provided with a spiral protrusion (222), and the pitch (P1) of the spiral protrusion (222) is 5mm-100mm.

6. The extrusion device (100) according to claim 5, characterized in that The lead (S1) of the spiral protrusion (222) is 10 mm to 200 mm.

7. The extrusion device (100) according to claim 1, characterized in that The number of the thread structures (22) of each extrusion assembly (20) is 2 to 84.

8. The extrusion device (100) according to claim 1, characterized in that Along the arrangement direction of all the extrusion assemblies (20), the minimum spacing (C1) between the two corresponding thread structures (22) on two adjacent extrusion assemblies (20) is 0.1 mm to 1 mm.

9. The extrusion device (100) according to claim 1, characterized in that Along the radial direction of the rotating shaft (21), the minimum distance (C2) between the thread structure (22) and the inner cavity wall of the accommodating cavity (101) is 0.05 mm-1 mm.

10. The extrusion device (100) according to claim 1, characterized in that The kneading structure (23) includes a plurality of kneading elements (231), which are arranged along the axial direction (Y) of the rotating shaft (21), and two adjacent kneading elements (231) are deflected along the circumferential direction (Z) of the rotating shaft (21).

11. The extrusion device (100) according to claim 10, characterized in that Along the axial direction (Y) of the rotating shaft (21), a plurality of kneading elements (231) are arranged in a spiral manner.

12. The extrusion device (100) according to claim 11, characterized in that The lead (S2) of the kneading structure (23) is 5 mm to 240 mm.

13. The extrusion device (100) according to claim 10, characterized in that The deflection angle of two adjacent kneading elements (231) along the circumferential direction (Z) of the rotation axis (21) is defined as θ1, wherein 0°<θ1≤90°.

14. The extrusion device (100) according to claim 10, characterized in that The thickness (T1) of the kneading element (231) along the axial direction (Y) of the rotating shaft (21) is 5 mm to 20 mm.

15. The extrusion device (100) according to claim 10, characterized in that The number of the kneading elements (231) in each of the extrusion components (20) ranges from 1 to 48.

16. The extrusion device (100) according to claim 10, characterized in that Along the arrangement direction of all the extrusion assemblies (20), the minimum distance (C3) between the two corresponding kneading elements (231) on two adjacent extrusion assemblies (20) is 0.1 mm to 2 mm.

17. The extrusion device (100) according to claim 10, characterized in that Along the radial direction of the rotating shaft (21), the minimum distance (C4) between the kneading element (231) and the inner cavity wall of the accommodating cavity (101) is 0.1 mm to 3 mm.

18. A method for preparing an electrode membrane, characterized in that: The preparation method comprises: The active material, the conductive agent and the binder are mixed to obtain an electrode material mixture (S410); The electrode material mixture is subjected to a fiberizing treatment (S420) by an extrusion device according to any one of claims 1 to 17; The electrode material mixture after the fiberization treatment is subjected to a calendering treatment to obtain the electrode membrane (S430).

19. The preparation method according to claim 18, characterized in that The temperature of the mixing process of the active material, the conductive agent, and the binder is less than 19°C.

20. The preparation method according to claim 18, characterized in that The mass ratio of the active material, the conductive agent and the binder is (90-99): (0.5-9): (0.5-10).

21. The preparation method according to claim 18, characterized in that The temperature of the fiberization treatment is 20°C-300°C.

22. The preparation method according to claim 18, characterized in that During the fiberizing process, the rotation speed of the rotating shaft of the extrusion device is 20 r / min-1000 r / min.

23. The preparation method according to claim 18, characterized in that The temperature of the calendering treatment is 40°C-200°C.

24. The preparation method according to claim 18, characterized in that The calendering process includes a first rolling process and a second rolling process, wherein the roll gap distance of the first rolling process is defined as D1, wherein 1000 μm<D1≤5000 μm, and the roll gap distance of the second rolling process is defined as D2, wherein 0 μm<D2≤1000 μm.

25. The preparation method according to claim 18, characterized in that The calendering treatment is carried out by differential rolling, and the differential speed ratio of the differential rolling is 1:1-4:

1.

26. A battery electrode (500), characterized in that: The battery pole piece (500) comprises a current collector (510) and the electrode membrane (520) prepared by the preparation method according to any one of claims 18 to 25, wherein the electrode membrane (520) is fixed on the current collector (510).

27. A battery, characterized in that: The battery comprises a housing and the battery pole piece (500) according to claim 26, and the battery pole piece (500) is arranged in the housing.

28. An electronic device, characterized in that: The electronic device includes a functional element and the battery according to claim 27, wherein the battery is used to power the functional element.

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