Battery cell, electrode assembly, battery device, and electric device

Abstract

A battery cell, an electrode assembly, a battery device, and an electrical device are provided. The battery cell includes an electrode assembly, which includes a first electrode, a second electrode, and a separator. The first and second electrodes have opposite polarities. The separator is disposed between the first and second electrodes along a first direction. At least one end of the first electrode has a first insulating member, and / or at least one end of the second electrode has a second insulating member. In a projection plane perpendicular to the first direction, the orthographic projections of all the first insulating members disposed on the first electrode and / or the orthographic projections of all the second insulating members disposed on the second electrode form a ring. By making the orthographic projections of all the first insulating members disposed on the first electrode and / or the orthographic projections of all the second insulating members disposed on the second electrode form a ring in a projection plane perpendicular to the first direction, the reliability of the battery cell is improved.

Description

Technical Field

[0001] This application relates to the field of batteries, and more specifically, to a battery cell, electrode assembly, battery device, and power-consuming device. Background Technology

[0002] Batteries are widely used in the new energy field, such as in electric vehicles and new energy vehicles, which have become a new trend in the automotive industry. The development of battery technology requires consideration of multiple design factors, such as energy density, cycle life, discharge capacity, and charge / discharge rate, as well as battery reliability. However, the reliability of batteries currently needs further improvement. Utility Model Content

[0003] This application provides a battery cell, electrode assembly, battery device, and power consumption device, which can improve the reliability of the battery.

[0004] In a first aspect, embodiments of this application provide a battery cell, the battery cell including an electrode assembly, the electrode assembly including a first electrode, a second electrode, and a separator, the first electrode and the second electrode having opposite polarities, the separator being disposed between the first electrode and the second electrode along a first direction; at least one end of the first electrode is provided with a first insulating member and / or at least one end of the second electrode is provided with a second insulating member, and in a projection plane perpendicular to the first direction, the orthographic projections of all the first insulating members disposed on the first electrode and / or the orthographic projections of all the second insulating members disposed on the second electrode form a ring.

[0005] In the above technical solution, at least one end of the first electrode is provided with a first insulating member. The first insulating member can cover the burrs or molten beads at the end of the first electrode, thereby reducing the risk of short circuit caused by the burrs or molten beads causing the first electrode and the second electrode to overlap. At least one end of the second electrode is provided with a second insulating member. The second insulating member can cover the burrs or molten beads at the end of the second electrode, thereby reducing the risk of short circuit caused by the burrs or molten beads causing the first electrode and the second electrode to overlap. By forming a ring with the orthographic projections of all the first insulating members provided on the first electrode in a projection plane perpendicular to the first direction and / or the orthographic projections of all the second insulating members provided on the second electrode in a projection plane perpendicular to the first direction, although the burrs or molten beads at the ends of the first electrode without first insulating members are not directly covered, the second insulating members can block the burrs or molten beads at the ends of the first electrode without first insulating members to a certain extent, thereby reducing the risk of short circuit caused by the burrs or molten beads causing the first electrode and the second electrode to overlap. Similarly, although burrs or molten beads at the end of the second electrode without the second insulating element are not directly covered, the first insulating element can, to some extent, block these burrs or molten beads, thereby reducing the risk of short circuits caused by the first and second electrodes overlapping due to burrs or molten beads. This is beneficial for improving the reliability of the battery cell. Furthermore, during the manufacturing of the electrode assembly, the first electrode, the separator, and the second electrode need to be extruded along a first direction. When the end of the first electrode with the first insulating element bends during extrusion, the first insulating element provides insulation, reducing the risk of short circuits caused by the first and second electrodes overlapping. When the end of the first electrode without the first insulating element bends during extrusion, the second insulating element provides insulation, reducing the risk of short circuits caused by the first and second electrodes overlapping, thus improving the reliability of the battery cell. Moreover, this electrode assembly can have the first insulating element only on a portion of the first electrode and the second insulating element only on a portion of the second electrode, achieving good insulation while also reducing manufacturing costs.

[0006] As an optional technical solution in this application embodiment, the first insulating element includes a solid electrolyte; and / or the second insulating element includes a solid electrolyte.

[0007] In the above technical solution, the first insulating component and / or the second insulating component includes a solid electrolyte. On the one hand, the solid electrolyte can provide insulation and reduce the risk of short circuits caused by the overlap of the first and second electrodes. On the other hand, the solid electrolyte allows ions to pass through. When the first insulating component and / or the second insulating component overlaps between the first and second electrodes, the solid electrolyte can form an ion pathway, which helps to reduce the internal resistance of the battery cell.

[0008] As an optional technical solution in this application embodiment, the first insulating element is a coating applied to the end of the first electrode sheet; and / or the second insulating element is a coating applied to the end of the second electrode sheet.

[0009] In the above technical solution, the first insulating component is a coating applied to the end of the first electrode. On one hand, the first insulating component can better cover burrs or molten beads at the end of the first electrode, thereby reducing the risk of short circuits caused by burrs or molten beads colliding between the first and second electrodes. On the other hand, the connection stability between the first insulating component and the first electrode is good; the first insulating component is not easily detached from the first electrode, thus providing stable protection for the first electrode. Similarly, the second insulating component is a coating applied to the end of the second electrode. On the one hand, the second insulating component can better cover burrs or molten beads at the end of the second electrode, thereby reducing the risk of short circuits caused by burrs or molten beads colliding between the first and second electrodes. On the other hand, the connection stability between the second insulating component and the second electrode is good; the second insulating component is not easily detached from the second electrode, thus providing stable protection for the second electrode.

[0010] As an optional technical solution of this application embodiment, the first electrode is provided with the first insulating member at both ends along the second direction, and the second electrode is provided with the second insulating member at both ends along the third direction; in the projection plane perpendicular to the first direction, the orthographic projections of the two first insulating members located at both ends of the first electrode and the orthographic projections of the two second insulating members located at both ends of the second electrode form a ring; the first direction, the second direction and the third direction are perpendicular to each other.

[0011] In the above technical solution, along the second direction, both ends of the first electrode are provided with first insulating members. The first insulating members can cover the burrs or molten beads at the ends of the first electrode, thereby reducing the risk of short circuit caused by the burrs or molten beads causing the first electrode and the second electrode to overlap. Along the third direction, both ends of the second electrode are provided with second insulating members. The second insulating members can cover the burrs or molten beads at the ends of the second electrode, thereby reducing the risk of short circuit caused by the burrs or molten beads causing the first electrode and the second electrode to overlap. Although the burrs or molten beads at both ends of the first electrode along the third direction are not directly covered, the second insulating members can block the burrs or molten beads at the ends of the first electrode along the third direction to a certain extent, thereby reducing the risk of short circuit caused by the burrs or molten beads causing the first electrode and the second electrode to overlap. Similarly, although the burrs or molten beads at both ends of the second electrode along the second direction are not directly covered, the first insulating member can, to a certain extent, block the burrs or molten beads at the ends of the second electrode along the second direction, thereby reducing the risk of short circuits caused by the burrs or molten beads colliding with the first electrode and the second electrode, which is beneficial to improving the reliability of the battery cell. Furthermore, during the manufacturing of the electrode assembly, the first electrode, the separator, and the second electrode need to be extruded along the first direction. When the two ends of the first electrode along the second direction bend during extrusion, the first insulating member can provide insulation, thereby reducing the risk of short circuits caused by the first electrode and the second electrode colliding. When the two ends of the first electrode along the third direction bend during extrusion, the second insulating member can provide insulation, thereby reducing the risk of short circuits caused by the first electrode and the second electrode colliding, which is beneficial to improving the reliability of the battery cell. Moreover, this electrode assembly can have the first insulating member only at the two ends of the first electrode along the second direction and the second insulating member at the two ends of the second electrode along the third direction, achieving good insulation while also reducing manufacturing costs.

[0012] As an optional technical solution in this application embodiment, the first electrode includes a first current collector and a first active material layer, the first active material layer being disposed on at least one side of the first current collector along the first direction; the first insulating member covers one end of the first current collector along the second direction.

[0013] In the above technical solution, the burrs or molten beads at the end of the first electrode along the second direction are mainly present on the first current collector. By covering one end of the first current collector along the second direction with the first insulating member, the burrs or molten beads at the end of the first electrode can be effectively covered, thereby reducing the risk of short circuit caused by the burrs or molten beads causing the first electrode and the second electrode to overlap, which is beneficial to improving the reliability of the battery cell.

[0014] As an optional technical solution in this application embodiment, the first insulating element covers one end of the first active material layer along the second direction.

[0015] In the above technical solution, by covering one end of the first active material layer along the second direction with the first insulating component, on the one hand, burrs or molten beads at the end of the first electrode sheet can be better covered, thereby reducing the risk of short circuits caused by the first and second electrode sheets overlapping due to burrs or molten beads. On the other hand, when the two ends of the first electrode sheet along the second direction are bent during the extrusion process, the first insulating component can play an insulating role, reducing the risk of short circuits caused by the contact between the first active material layer and the second electrode sheet, which is beneficial to improving the reliability of the battery cell.

[0016] As an optional technical solution of this application embodiment, the first active material layer is provided on both sides of the first current collector along the first direction; the first insulating member includes a first insulating part, a second insulating part and a third insulating part, the second insulating part connects the first insulating part and the third insulating part, the second insulating part covers one end of the first current collector along the second direction and one end of the first active material layer along the second direction, along the first direction, the first insulating part is located on one side of the first active material layer away from the first current collector, and the third insulating part is located on the other side of the first active material layer away from the first current collector.

[0017] In the above technical solution, the first insulating portion, the second insulating portion, and the third insulating portion can completely cover the end of the first electrode sheet along the second direction, better covering the burrs or molten beads at the end of the first electrode sheet, thereby reducing the risk of short circuit caused by the first electrode sheet and the second electrode sheet overlapping due to burrs or molten beads. Furthermore, along the first direction, the first insulating portion is located on the side of a first active material layer facing away from the first current collector, protecting the side of the first active material layer facing away from the first current collector, thereby reducing the risk of short circuit caused by the contact between the first active material layer and the second electrode sheet. The third insulating portion is located on the side of another first active material layer facing away from the first current collector, protecting the side of the other first active material layer facing away from the first current collector, thereby reducing the risk of short circuit caused by the contact between the other first active material layer and the second electrode sheet, which is beneficial to improving the reliability of the battery cell.

[0018] As an optional technical solution in this application embodiment, the second electrode includes a second current collector and a second active material layer, the second active material layer being disposed on at least one side of the second current collector along the first direction; the second insulating member covers one end of the second current collector along the third direction.

[0019] In the above technical solution, the burrs or molten beads at the end of the second electrode along the third direction are mainly present on the second current collector. By covering one end of the second current collector along the third direction with the second insulating member, the burrs or molten beads at the end of the second electrode can be effectively covered, thereby reducing the risk of short circuit caused by the burrs or molten beads causing the first electrode and the second electrode to overlap, which is beneficial to improving the reliability of the battery cell.

[0020] As an optional technical solution in this application embodiment, the second insulating member covers one end of the second active material layer along the third direction.

[0021] In the above technical solution, by covering one end of the second active material layer along a third direction with the second insulating component, on the one hand, burrs or molten beads at the end of the second electrode can be better covered, thereby reducing the risk of short circuits caused by the first and second electrodes overlapping due to burrs or molten beads. On the other hand, when the two ends of the first electrode along the third direction are bent during extrusion, the second insulating component can play an insulating role, reducing the risk of short circuits caused by the second active material layer contacting the first electrode, which is beneficial to improving the reliability of the battery cell.

[0022] As an optional technical solution of this application embodiment, along the first direction, the second active material layer is provided on both sides of the second current collector; the second insulating member includes a fourth insulating part, a fifth insulating part and a sixth insulating part, the fifth insulating part connects the fourth insulating part and the sixth insulating part, the fifth insulating part covers one end of the second current collector along the third direction and one end of the second active material layer along the third direction, along the first direction, the fourth insulating part is located on the side of one second active material layer away from the second current collector, and the sixth insulating part is located on the side of another second active material layer away from the second current collector.

[0023] In the above technical solution, the fourth, fifth, and sixth insulating portions can completely cover the end of the second electrode sheet along the third direction, better covering burrs or molten beads at the end of the second electrode sheet, thereby reducing the risk of short circuits caused by burrs or molten beads colliding with the first and second electrode sheets. Furthermore, along the first direction, the fourth insulating portion is located on the side of one second active material layer facing away from the second current collector, protecting this side and reducing the risk of a short circuit due to contact between the second active material layer and the first electrode sheet. The sixth insulating portion is located on the side of another second active material layer facing away from the second current collector, further protecting this side and reducing the risk of a short circuit due to contact between the other second active material layer and the first electrode sheet, thus improving the reliability of the battery cell.

[0024] As an optional technical solution in this application embodiment, the first electrode is provided with a first electrode tab, which is connected to one end of the first electrode along the second direction; and / or the second electrode is provided with a second electrode tab, which is connected to one end of the second electrode along the third direction.

[0025] In the above technical solution, a first insulating member is provided at both ends of the first electrode sheet along the second direction, and a first electrode tab is connected to one end of the first electrode sheet along the second direction. Thus, the first electrode sheet has a first insulating member at the end where the first electrode tab is provided, and also at the opposite end. When the first electrode tab is manufactured by die-cutting, the first insulating member can cover the die-cut side of the first electrode sheet, thereby shielding burrs or molten beads generated during die-cutting and reducing the risk of short circuits caused by burrs or molten beads colliding between the first and second electrode sheets. Similarly, a second insulating member is provided at both ends of the second electrode sheet along the third direction, and a second electrode tab is connected to one end of the second electrode sheet along the third direction. Thus, the second electrode sheet has a second insulating member at the end where the second electrode tab is provided, and also at the opposite end. When the second electrode tab is manufactured by die-cutting, the second insulating component can cover the die-cut side of the second electrode, thereby shielding the burrs or molten beads generated by die-cutting and reducing the risk of short circuit caused by the burrs or molten beads causing the first electrode and the second electrode to overlap.

[0026] As an optional technical solution in this application embodiment, the first electrode is provided with a first electrode tab, which is connected to one end of the first electrode along the third direction; and / or the second electrode is provided with a second electrode tab, which is connected to one end of the second electrode along the second direction.

[0027] In the above technical solution, a first insulating member is provided at both ends of the first electrode along the second direction, and a first tab is connected to one end of the first electrode along the third direction. Thus, the first insulating member and the first tab are located at different positions on the first electrode. The first insulating member can cover the slit side of the first electrode, thereby shielding burrs or molten beads generated during slitting and reducing the risk of short circuits caused by burrs or molten beads colliding between the first and second electrodes. Similarly, a second insulating member is provided at both ends of the second electrode along the third direction, and a second tab is connected to one end of the second electrode along the second direction. Thus, the second insulating member and the second tab are located at different positions on the second electrode. The second insulating member can cover the slit side of the second electrode, thereby shielding burrs or molten beads generated during slitting and reducing the risk of short circuits caused by burrs or molten beads colliding between the first and second electrodes.

[0028] As an optional technical solution in this application embodiment, the first electrode includes a first current collector, the first current collector and the first electrode tab are integrally formed; and / or the second electrode includes a second current collector, the second current collector and the second electrode tab are integrally formed.

[0029] In the above technical solution, the first current collector and the first tab are integrally formed, resulting in better overall integrity and higher connection strength between them, which also helps to reduce the internal resistance of the battery cell. Similarly, the second current collector and the second tab are integrally formed, resulting in better overall integrity and higher connection strength between them, which also helps to reduce the internal resistance of the battery cell.

[0030] As an optional technical solution in this application embodiment, the first electrode is provided with the first insulating element at both ends along the third direction; and / or the second electrode is provided with the second insulating element at both ends along the second direction.

[0031] In the above technical solution, first insulating elements are provided at both ends of the first electrode along the second direction and at both ends of the first electrode along the third direction. This allows the first insulating elements to completely cover the first electrode, resulting in better insulation. Similarly, second insulating elements are provided at both ends of the second electrode along the second direction and at both ends of the second electrode along the third direction. This allows the second insulating elements to completely cover the second electrode, resulting in better insulation.

[0032] As an optional technical solution in this application embodiment, the first electrode is a negative electrode, and both ends of the first electrode along the second direction extend beyond the second electrode, with each end extending beyond the second electrode by a length L1, satisfying: 0.1mm≤L1≤10mm; and / or both ends of the first electrode along the third direction extend beyond the second electrode, with each end extending beyond the second electrode by a length L2, satisfying: 0.1mm≤L2≤10mm.

[0033] In the above technical solution, when L1 ≥ 0.1 mm, the length of the first electrode extending beyond the second electrode along the second direction is relatively large, which helps reduce assembly difficulty and achieve an overhang design, thus reducing the risk of metal ion precipitation. When L1 ≤ 10 mm, the length of the first electrode extending beyond the second electrode along the second direction is not excessive, which helps reduce the volume of the electrode assembly, improve the internal space utilization of the battery cell, and increase the energy density of the battery cell. Therefore, when 0.1 mm ≤ L1 ≤ 10 mm, it is possible to both reduce assembly difficulty and achieve an overhang design, while also increasing the energy density of the battery cell.

[0034] When L2 ≥ 0.1 mm, the first electrode extends significantly beyond the second electrode along a third direction, which helps reduce assembly difficulty, enables overhang design, and reduces the risk of metal ion precipitation. When L2 ≤ 10 mm, the first electrode does not extend excessively beyond the second electrode along a third direction, which helps reduce the volume of the electrode assembly, improves the internal space utilization of the battery cell, and increases the energy density of the battery cell. Therefore, when 0.1 mm ≤ L2 ≤ 10 mm, it is possible to both reduce assembly difficulty and enable overhang design while increasing the energy density of the battery cell.

[0035] As an optional technical solution in the embodiments of this application, 0.3mm≤L1≤3mm, and / or 0.3mm≤L2≤3mm.

[0036] In the above technical solution, when L1 ≥ 0.3 mm, the first electrode extends further beyond the second electrode along the second direction, which is more conducive to reducing assembly difficulty and realizing an overhang design, thus reducing the risk of metal ion precipitation. When L1 ≤ 3 mm, the length of the first electrode extending beyond the second electrode along the second direction is not too large, which helps to reduce the volume of the electrode assembly, improve the internal space utilization of the battery cell, and increase the energy density of the battery cell. Therefore, when 0.3 mm ≤ L1 ≤ 3 mm, it can both reduce assembly difficulty and realize an overhang design, and also improve the energy density of the battery cell.

[0037] When L2 ≥ 0.3 mm, the first electrode extends significantly beyond the second electrode along a third direction, which is more conducive to reducing assembly difficulty and achieving an overhang design, thus reducing the risk of metal ion precipitation. When L2 ≤ 3 mm, the first electrode does not extend excessively beyond the second electrode along a third direction, which helps to reduce the volume of the electrode assembly, improve the internal space utilization of the battery cell, and increase the energy density of the battery cell. Therefore, when 0.3 mm ≤ L2 ≤ 3 mm, it is possible to both reduce assembly difficulty and achieve an overhang design while also increasing the energy density of the battery cell.

[0038] As an optional technical solution in this application embodiment, the insulating element is a solid electrolyte layer.

[0039] In the above technical solution, when the separator is a solid electrolyte layer, the battery cell is a solid battery cell with high energy density.

[0040] Secondly, embodiments of this application also provide an electrode assembly, the electrode assembly including a first electrode, a second electrode, and an insulating member, wherein the first electrode and the second electrode have opposite polarities, and the insulating member is disposed between the first electrode and the second electrode along a first direction; at least one end of the first electrode is provided with a first insulating member and / or at least one end of the second electrode is provided with a second insulating member, and in a projection plane perpendicular to the first direction, the orthographic projections of all the first insulating members disposed on the first electrode and / or the orthographic projections of all the second insulating members disposed on the second electrode form a ring.

[0041] As an optional technical solution in this application embodiment, the first insulating element includes a solid electrolyte; and / or the second insulating element includes a solid electrolyte.

[0042] In the above technical solution, the first insulating component and / or the second insulating component includes a solid electrolyte. On the one hand, the solid electrolyte can provide insulation and reduce the risk of short circuits caused by the overlap of the first and second electrodes. On the other hand, the solid electrolyte allows ions to pass through. When the first insulating component and / or the second insulating component overlaps between the first and second electrodes, the solid electrolyte can form an ion pathway, which helps to reduce the internal resistance of the battery cell.

[0043] As an optional technical solution of this application embodiment, the first electrode is provided with the first insulating member at both ends along the second direction, and the second electrode is provided with the second insulating member at both ends along the third direction; in the projection plane perpendicular to the first direction, the orthographic projections of the two first insulating members located at both ends of the first electrode and the orthographic projections of the two second insulating members located at both ends of the second electrode form a ring; the first direction, the second direction and the third direction are perpendicular to each other.

[0044] In the above technical solution, along the second direction, both ends of the first electrode are provided with first insulating members. The first insulating members can cover the burrs or molten beads at the ends of the first electrode, thereby reducing the risk of short circuit caused by the burrs or molten beads causing the first electrode and the second electrode to overlap. Along the third direction, both ends of the second electrode are provided with second insulating members. The second insulating members can cover the burrs or molten beads at the ends of the second electrode, thereby reducing the risk of short circuit caused by the burrs or molten beads causing the first electrode and the second electrode to overlap. Although the burrs or molten beads at both ends of the first electrode along the third direction are not directly covered, the second insulating members can block the burrs or molten beads at the ends of the first electrode along the third direction to a certain extent, thereby reducing the risk of short circuit caused by the burrs or molten beads causing the first electrode and the second electrode to overlap. Similarly, although the burrs or molten beads at both ends of the second electrode along the second direction are not directly covered, the first insulating member can, to a certain extent, block the burrs or molten beads at the ends of the second electrode along the second direction, thereby reducing the risk of short circuits caused by the burrs or molten beads colliding with the first electrode and the second electrode, which is beneficial to improving the reliability of the battery cell. Furthermore, during the manufacturing of the electrode assembly, the first electrode, the separator, and the second electrode need to be extruded along the first direction. When the two ends of the first electrode along the second direction bend during extrusion, the first insulating member can provide insulation, thereby reducing the risk of short circuits caused by the first electrode and the second electrode colliding. When the two ends of the first electrode along the third direction bend during extrusion, the second insulating member can provide insulation, thereby reducing the risk of short circuits caused by the first electrode and the second electrode colliding, which is beneficial to improving the reliability of the battery cell. Moreover, this electrode assembly can have the first insulating member only at the two ends of the first electrode along the second direction and the second insulating member at the two ends of the second electrode along the third direction, achieving good insulation while also reducing manufacturing costs.

[0045] As an optional technical solution in this application embodiment, the first electrode is provided with a first electrode tab, which is connected to one end of the first electrode along the second direction; the second electrode is provided with a second electrode tab, which is connected to one end of the second electrode along the third direction.

[0046] In the above technical solution, a first insulating member is provided at both ends of the first electrode sheet along the second direction, and a first electrode tab is connected to one end of the first electrode sheet along the second direction. Thus, the first electrode sheet has a first insulating member at the end where the first electrode tab is provided, and also at the opposite end. When the first electrode tab is manufactured by die-cutting, the first insulating member can cover the die-cut side of the first electrode sheet, thereby shielding burrs or molten beads generated during die-cutting and reducing the risk of short circuits caused by burrs or molten beads colliding between the first and second electrode sheets. Similarly, a second insulating member is provided at both ends of the second electrode sheet along the third direction, and a second electrode tab is connected to one end of the second electrode sheet along the third direction. Thus, the second electrode sheet has a second insulating member at the end where the second electrode tab is provided, and also at the opposite end. When the second electrode tab is manufactured by die-cutting, the second insulating component can cover the die-cut side of the second electrode, thereby shielding the burrs or molten beads generated by die-cutting and reducing the risk of short circuit caused by the burrs or molten beads causing the first electrode and the second electrode to overlap.

[0047] As an optional technical solution in this application embodiment, the insulating element is a solid electrolyte layer.

[0048] In the above technical solutions, when the insulating component is a solid electrolyte layer, it is beneficial to reduce the volume of the electrode assembly and improve the energy density.

[0049] Thirdly, embodiments of this application also provide an electrode assembly manufacturing method, the electrode assembly manufacturing method comprising: providing a first electrode sheet; providing a second electrode sheet, the second electrode sheet having the opposite polarity to the first electrode sheet, wherein at least one end of the first electrode sheet is provided with a first insulating member, and / or at least one end of the second electrode sheet is provided with a second insulating member; providing an insulating member; and stacking the first electrode sheet, the insulating member, and the second electrode sheet along a first direction, such that the insulating member is disposed between the first electrode sheet and the second electrode sheet along the first direction, and in a projection plane perpendicular to the first direction, the orthographic projections of all the first insulating members disposed on the first electrode sheet and / or the orthographic projections of all the second insulating members disposed on the second electrode sheet form a ring.

[0050] As an optional technical solution in this application embodiment, the first electrode sheet is provided with the first insulating element at both ends along the second direction, and the second electrode sheet is provided with the second insulating element at both ends along the third direction. In a projection plane perpendicular to the first direction, the orthographic projections of the two first insulating elements located at both ends of the first electrode sheet and the orthographic projections of the two second insulating elements located at both ends of the second electrode sheet form a ring. The first direction, the second direction, and the third direction are perpendicular to each other. Providing the first electrode sheet includes: providing a first electrode sheet strip; coating the two ends of the first electrode sheet strip in the width direction with an insulating coating; and cutting the first electrode sheet strip into multiple first electrode sheets.

[0051] In the above technical solution, by coating the two ends of the first electrode strip in the width direction with insulating slurry, and then cutting the first electrode strip into multiple first electrodes, multiple first electrodes can be manufactured at one time, which is beneficial to improving the manufacturing efficiency of the first electrodes and reducing the manufacturing cost of the electrode assembly.

[0052] As an optional technical solution in this application embodiment, providing the first electrode strip includes: providing a first electrode substrate; cutting the first electrode substrate into a plurality of first electrode blanks; and die-cutting electrode tabs into the first electrode blanks to form the first electrode strip.

[0053] In the above technical solution, multiple first electrode blanks can be formed by slitting the first electrode substrate. The first electrode strip can be formed by die-cutting the electrode tabs on the first electrode blanks. The above manufacturing method is beneficial to improving the manufacturing efficiency of the first electrode strip and reducing the manufacturing cost of the electrode assembly.

[0054] As an optional technical solution in this application embodiment, providing the second electrode sheet includes: providing a second electrode sheet strip; coating both ends of the second electrode sheet strip in the width direction with an insulating coating; and cutting the second electrode sheet strip into a plurality of second electrode sheets.

[0055] In the above technical solution, by coating the two ends of the second electrode strip in the width direction with insulating slurry, and then cutting the second electrode strip into multiple second electrodes, multiple second electrodes can be manufactured at one time, which is beneficial to improving the manufacturing efficiency of the second electrodes and reducing the manufacturing cost of the electrode assembly.

[0056] As an optional technical solution in this application embodiment, providing the second electrode strip includes: providing a second electrode substrate; cutting the second electrode substrate into a plurality of second electrode blanks; and die-cutting tabs into the second electrode blanks to form the second electrode strip.

[0057] In the above technical solution, multiple second electrode blanks can be formed by slitting the second electrode substrate. The electrode tabs can be die-cut into the second electrode blanks to form the second electrode strip. The above manufacturing method is beneficial to improve the manufacturing efficiency of the second electrode strip and reduce the manufacturing cost of the electrode assembly.

[0058] As an optional technical solution in this application embodiment, the insulating coating includes a solid electrolyte.

[0059] In the above technical solution, the insulating coating includes a solid electrolyte. On the one hand, the solid electrolyte can provide insulation and reduce the risk of short circuits caused by the overlap of the first and second electrodes. On the other hand, the solid electrolyte allows ions to pass through. When the first insulating component and / or the second insulating component overlaps between the first and second electrodes, the solid electrolyte can form an ion pathway, which helps to reduce the internal resistance of the battery cell.

[0060] As an optional technical solution in this application embodiment, the separator is a solid electrolyte layer. After the step of stacking the first electrode, the separator and the second electrode along the first direction, the electrode assembly manufacturing method further includes: performing isostatic pressing on the stacked first electrode, the separator and the second electrode.

[0061] In the above technical solution, when the separator is a solid electrolyte layer, it is beneficial to reduce the volume of the electrode assembly and improve the energy density. By performing isostatic pressing on the stacked first electrode, the separator, and the second electrode, it is beneficial to achieve densification of the electrode assembly and further reduce the volume of the electrode assembly.

[0062] Fourthly, embodiments of this application also provide a battery device, the battery device comprising the aforementioned battery cell.

[0063] Fifthly, embodiments of this application also provide an electrical device, the electrical device including the aforementioned battery cell, the battery cell being used to provide electrical energy to the electrical device. Attached Figure Description

[0064] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0065] Figure 1 This application provides structural schematic diagrams of vehicles for some embodiments;

[0066] Figure 2 Exploded views of battery devices provided in some embodiments of this application;

[0067] Figure 3 Exploded views of a single battery cell provided in some embodiments of this application;

[0068] Figure 4 A top view schematic diagram of an electrode assembly provided in some embodiments of this application;

[0069] Figure 5 for Figure 4 Sectional view at position AA:

[0070] Figure 6 for Figure 4 A cross-sectional view at position BB in the middle;

[0071] Figure 7 A cross-sectional view of a first electrode provided for some embodiments of this application;

[0072] Figure 8 Cross-sectional view of the first electrode provided for other embodiments of this application;

[0073] Figure 9 Cross-sectional view of a first electrode provided for some embodiments of this application;

[0074] Figure 10 Cross-sectional view of the second pole piece provided in some embodiments of this application;

[0075] Figure 11 Cross-sectional view of the second pole piece provided for other embodiments of this application;

[0076] Figure 12 Cross-sectional view of the second pole piece provided for some embodiments of this application;

[0077] Figure 13 A top view schematic diagram of an electrode assembly provided for other embodiments of this application;

[0078] Figure 14 A schematic block diagram illustrating a method for manufacturing an electrode assembly according to some embodiments of this application;

[0079] Figure 15 A schematic block diagram illustrating a method for manufacturing an electrode assembly according to other embodiments of this application;

[0080] Figure 16 A schematic block diagram illustrating a method for manufacturing an electrode assembly according to some embodiments of this application;

[0081] Figure 17 A schematic block diagram illustrating a method for manufacturing an electrode assembly according to further embodiments of this application;

[0082] Figure 18 Schematic block diagrams of electrode assembly manufacturing methods provided in some embodiments of this application;

[0083] Figure 19 This is a schematic block diagram illustrating a method for manufacturing an electrode assembly according to other embodiments of this application.

[0084] Icons: 10-Box; 11-First part; 12-Second part; 20-Battery cell; 21-Casing; 211-Shell; 212-End cap; 22-Electrode assembly; 221-First electrode; 2211-First current collector; 2212-First active material layer; 222-Second electrode; 2221-Second current collector; 2222-Second active material layer; 223-Separator; 224-First insulating component; 2241-First insulating part; 2242-Second insulating part; 2243-Third insulating part; 225-Second insulating component; 2251-Fourth insulating part; 2252-Fifth insulating part; 2253-Sixth insulating part; 226-First tab; 227-Second tab; 30-Electrode assembly manufacturing method; 100-Battery device; 200-Controller; 300-Motor; 1000-Vehicle. Detailed Implementation

[0085] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0086] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having," and any variations thereof, in the description, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the description, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or hierarchy.

[0087] In this application, the reference to "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments.

[0088] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0089] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0090] In the embodiments of this application, the same reference numerals denote the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width, and other dimensions of various components in the embodiments of this application shown in the accompanying drawings, as well as the overall thickness, length, width, and other dimensions of the integrated device, are merely illustrative and should not constitute any limitation on this application.

[0091] In this application, "multiple" means two or more (including two).

[0092] In this embodiment of the application, the battery cell can be a secondary battery, which refers to a battery cell that can be recharged to activate the active materials and continue to be used after the battery cell has been discharged.

[0093] Battery cells include, but are not limited to, lithium-ion batteries, sodium-ion batteries, sodium-lithium-ion batteries, lithium metal batteries, sodium metal batteries, lithium-sulfur batteries, magnesium-ion batteries, nickel-metal hydride batteries, nickel-cadmium batteries, lead-acid batteries, etc.

[0094] A single battery cell typically includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator. During the charging and discharging process of a single battery cell, active ions (such as lithium ions) repeatedly insert and extract between the positive and negative electrodes. The separator, positioned between the positive and negative electrodes, reduces the risk of short circuits while allowing active ions to pass through.

[0095] In some embodiments, the positive electrode can be a positive electrode sheet, which may include a positive current collector and a positive active material disposed on at least one surface of the positive current collector.

[0096] As an example, the positive current collector has two surfaces opposite each other in its own thickness direction, and the positive active material is disposed on either or both of the two opposite surfaces of the positive current collector.

[0097] As an example, the positive electrode current collector can be a metal foil or a composite current collector. For example, as a metal foil, it can be aluminum with a silver-plated surface, stainless steel with a silver-plated surface, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel, or titanium, etc. Composite current collectors can include a polymer material base layer and a metal layer. Composite current collectors can be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0098] As an example, the positive electrode active material may include at least one of the following materials: lithium phosphate, lithium transition metal oxide, and their respective modified compounds. However, this application is not limited to these materials, and other conventional materials that can be used as positive electrode active materials in battery cells may also be used. These positive electrode active materials may be used alone or in combination of two or more. Examples of lithium phosphate may include, but are not limited to, at least one of lithium iron phosphate (such as LiFePO4 (also referred to as LFP)), lithium iron phosphate and carbon composites, lithium manganese phosphate (such as LiMnPO4), lithium manganese phosphate and carbon composites, lithium iron manganese phosphate, and lithium iron manganese phosphate and carbon composites. Examples of lithium transition metal oxide may include, but are not limited to, lithium cobalt oxide (such as LiCoO2), lithium nickel oxide (such as LiNiO2), lithium manganese oxide (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, and lithium nickel cobalt manganese oxide (such as LiNi). 1 / 3 Co 1 / 3Mn 1 / 3 O2 (also known as NCM) 333 LiNi 0.5 Co 0.2 Mn 0.3 O2 (also known as NCM) 523 LiNi 0.5 Co 0.25 Mn 0.25 O2 (also known as NCM) 211 LiNi 0.6 Co 0.2 Mn 0.2 O2 (also known as NCM) 622 LiNi 0.8 Co 0.1 Mn 0.1 O2 (also known as NCM) 811 ), lithium nickel cobalt aluminum oxide (such as LiNi) 0.85 Co 0.15 Al 0.05At least one of O2 and its modified compounds.

[0099] In some embodiments, the positive electrode can be a foamed metal. The foamed metal can be foamed nickel, foamed copper, foamed aluminum, foamed alloys, etc. When foamed metal is used as the positive electrode, the surface of the foamed metal may or may not contain a positive electrode active material. As an example, lithium source material, potassium metal, or sodium metal can also be filled and / or deposited within the foamed metal, where the lithium source material is lithium metal and / or a lithium-rich material.

[0100] In some embodiments, the negative electrode can be a negative electrode sheet, and the negative electrode sheet can include a negative current collector.

[0101] As an example, the negative electrode current collector can be a metal foil, a foamed metal, or a composite current collector. For example, as a metal foil, it can be aluminum with a silver-plated surface, stainless steel with a silver-plated surface, stainless steel, copper, aluminum, nickel, carbon electrodes, carbon, nickel, or titanium, etc. Foamed metal can be nickel foam, copper foam, aluminum foam, foam alloy, etc. Composite current collectors can include a polymer material base layer and a metal layer. Composite current collectors can be formed by forming a metal material (copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0102] As an example, the negative electrode sheet may include a negative current collector and a negative active material disposed on at least one surface of the negative current collector.

[0103] As an example, the negative electrode current collector has two surfaces opposite each other in its own thickness direction, and the negative electrode active material is disposed on either or both of the two opposite surfaces of the negative electrode current collector.

[0104] As an example, the negative electrode active material may be a negative electrode active material known in the art for use in battery cells. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, and lithium titanate, etc. Silicon-based materials may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. Tin-based materials may be selected from at least one of elemental tin, tin oxide compounds, and tin alloys. However, this application is not limited to these materials, and other conventional materials that can be used as negative electrode active materials in battery cells may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0105] In some embodiments, the positive current collector can be made of aluminum, and the negative current collector can be made of copper.

[0106] In some embodiments, the separator is a separator membrane. The separator membrane can be any known porous structure separator membrane with good chemical and mechanical stability.

[0107] As an example, the material of the separator may include at least one of glass fiber, nonwoven fabric, polyethylene, polypropylene, and polyvinylidene fluoride. The separator may be a single-layer film or a multi-layer composite film. When the separator is a multi-layer composite film, the materials of each layer may be the same or different. The separator may be a separate component located between the positive and negative electrodes, or it may be attached to the surfaces of the positive and negative electrodes.

[0108] In some embodiments, the separator is a solid electrolyte layer. The solid electrolyte layer is disposed between the positive and negative electrodes, serving both to transport ions and to isolate the positive and negative electrodes.

[0109] In some embodiments, the battery cell also includes an electrolyte, which acts as a conductor of ions between the positive and negative electrodes. The electrolyte can be liquid, gel-like, or solid. Liquid electrolytes include electrolyte salts and solvents.

[0110] In some embodiments, the electrolyte salt may include at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluorooxalate borate, lithium dioxalate borate, lithium difluorodioxalate phosphate, and lithium tetrafluorooxalate phosphate.

[0111] In some embodiments, the solvent may include at least one selected from ethylene carbonate, propylene carbonate, methyl ethyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, butyl carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, sulfolane, dimethyl sulfone, methyl ethyl sulfone, and diethyl sulfone. The solvent may also be an ether solvent. Ether solvents may include one or more selected from ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1,3-dioxolane, tetrahydrofuran, methyl tetrahydrofuran, diphenyl ether, and crown ethers.

[0112] Among them, the gel electrolyte includes a polymer as the electrolyte backbone network, combined with an ionic liquid - lithium salt.

[0113] Solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0114] As an example, polymer solid electrolytes can be polyether (polyoxyethylene), polysiloxane, polycarbonate, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, monoionic polymers, polyionic liquids-lithium salts, cellulose, etc.

[0115] As an example, inorganic solid electrolytes may include one or more of the following: oxide solid electrolytes (crystalline perovskite, sodium superconducting ion conductor, garnet, amorphous LiPON thin film), sulfide solid electrolytes (crystalline lithium superconducting ion conductor (lithium germanium phosphate sulfide, silver sulfide germanium ore), amorphous sulfides), halide solid electrolytes, nitride solid electrolytes, and hydride solid electrolytes.

[0116] As an example, composite solid electrolytes are formed by adding inorganic solid electrolyte fillers to polymer solid electrolytes.

[0117] In some implementations, the electrode assembly is a stacked structure.

[0118] As an example, multiple positive and negative electrode plates can be set, and multiple positive and multiple negative electrode plates can be stacked alternately.

[0119] As an example, multiple separators can be provided, each positioned between any adjacent positive or negative electrode plates.

[0120] As an example, the separator can be continuously arranged between any adjacent positive or negative electrode plates by folding or rolling.

[0121] In some implementations, the electrode assembly may be flat or polygonal in shape.

[0122] In some embodiments, the electrode assembly is provided with tabs that allow current to be drawn from the electrode assembly. The tabs include a positive tab and a negative tab.

[0123] In some embodiments, the battery cell may include a housing. The housing is used to encapsulate components such as electrode assemblies and electrolytes. The housing can be a rigid housing, such as a steel housing, an aluminum housing, or a composite metal housing (such as a copper-aluminum composite housing), or a flexible housing, such as an aluminum-plastic film housing or a heat-shrink film housing.

[0124] In some embodiments, the housing can be a sealed structure or a non-sealed structure. As an example, when the housing is a sealed structure, it can protect the electrode assembly and prevent, to some extent, electrolyte leakage. When the housing is a non-sealed structure, it can still protect the electrode assembly, and a sealing bag may be included between the housing and the electrode assembly to encapsulate the electrode assembly and electrolyte. Specifically, the sealing bag can be a bag-shaped insulating component or an aluminum-plastic film.

[0125] As an example, a battery cell can be a prismatic battery cell or a battery cell of other shapes. Prismatic battery cells include prismatic battery cells, blade-shaped battery cells, and multi-prismatic battery cells, such as hexagonal prismatic battery cells.

[0126] The battery apparatus mentioned in the embodiments of this application may include one or more battery cell assemblies for providing voltage and capacity. A battery cell assembly may include multiple battery cells, which are connected in series, parallel, or mixed connections via a busbar.

[0127] In some embodiments, a battery cell assembly is typically formed by arranging multiple battery cells; as an example, a battery cell assembly can be a battery module, which is formed by arranging multiple battery cells and fixing them together to form an independent module.

[0128] As an example, a battery module can be formed by bundling multiple battery cells together with cable ties.

[0129] In some embodiments, the battery device may be a battery pack, which may include a housing and one or more individual battery cells housed within the housing.

[0130] As an example, the battery cell assembly can be a battery module, which can be housed in a housing by fixing the battery module in the housing.

[0131] As an example, battery cell assemblies can also be housed in a housing by directly fixing multiple battery cells to the housing.

[0132] As an example, the enclosure may include a first part and a second part. The first and second parts are fastened together to form a closed space inside the enclosure to house the individual battery cells. Here, "closed" refers to covering or shutting off; it can be sealed or not sealed. The first part may be a top cover or a bottom plate.

[0133] As an example, the enclosure may include a top cover, a frame, and a bottom plate. The top cover and bottom plate are connected to the frame, creating an enclosed space inside the enclosure to house the individual battery cells.

[0134] As an example, the housing can be part of the vehicle's chassis structure. For instance, the housing's roof can be at least part of the vehicle's floor, or the housing's frame can be at least part of the vehicle's crossbeams and longitudinal beams.

[0135] In some embodiments, the battery device refers to an energy storage device, which includes a housing with a door on at least one side. Energy storage devices include energy storage containers, energy storage cabinets, etc.

[0136] Currently, judging from market trends, battery applications are becoming increasingly widespread. Batteries are not only used in energy storage systems such as hydropower, thermal power, wind power, and solar power plants, but also extensively in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace. With the continuous expansion of battery applications, market demand is also constantly increasing.

[0137] The development of battery technology requires consideration of multiple design factors, such as energy density, cycle life, discharge capacity, and charge / discharge rate. Additionally, battery reliability must be taken into account. However, current battery reliability needs further improvement.

[0138] During the manufacturing of electrode assemblies, positive and negative electrode sheets need to be cut. Mechanical cutting creates burrs at the edges of the electrode sheets, while laser cutting creates molten beads. When the positive and negative electrode sheets are stacked, these burrs or molten beads can easily puncture the separator, causing a short circuit between the positive and negative electrodes. Furthermore, burrs or molten beads may also bypass the separator, leading to a short circuit. Therefore, the reliability of the batteries currently needs further improvement.

[0139] In view of this, embodiments of this application provide a battery cell, which includes an electrode assembly. The electrode assembly includes a first electrode, a second electrode, and a separator. The first electrode and the second electrode have opposite polarities. Along a first direction, the separator is disposed between the first electrode and the second electrode. At least one end of the first electrode is provided with a first insulating member, and / or at least one end of the second electrode is provided with a second insulating member. In a projection plane perpendicular to the first direction, the orthographic projections of all the first insulating members disposed on the first electrode and / or the orthographic projections of all the second insulating members disposed on the second electrode form a ring.

[0140] At least one end of the first electrode is provided with a first insulating member, which can cover burrs or molten beads at the end of the first electrode, thereby reducing the risk of short circuit caused by burrs or molten beads causing the first electrode and the second electrode to overlap. At least one end of the second electrode is provided with a second insulating member, which can cover burrs or molten beads at the end of the second electrode, thereby reducing the risk of short circuit caused by burrs or molten beads causing the first electrode and the second electrode to overlap. By forming a ring with the orthographic projections of all the first insulating members provided on the first electrode in a projection plane perpendicular to the first direction and / or the orthographic projections of all the second insulating members provided on the second electrode in a projection plane perpendicular to the first direction, although the burrs or molten beads at the ends of the first electrode without first insulating members are not directly covered, the second insulating members can block the burrs or molten beads at the ends of the first electrode without first insulating members to a certain extent, thereby reducing the risk of short circuit caused by burrs or molten beads causing the first electrode and the second electrode to overlap. Similarly, although burrs or molten beads at the end of the second electrode without the second insulating element are not directly covered, the first insulating element can, to some extent, block these burrs or molten beads, thereby reducing the risk of short circuits caused by the first and second electrodes overlapping due to burrs or molten beads. This is beneficial for improving the reliability of the battery cell. Furthermore, during the manufacturing of the electrode assembly, the first electrode, the separator, and the second electrode need to be extruded along a first direction. When the end of the first electrode with the first insulating element bends during extrusion, the first insulating element provides insulation, reducing the risk of short circuits caused by the first and second electrodes overlapping. When the end of the first electrode without the first insulating element bends during extrusion, the second insulating element provides insulation, reducing the risk of short circuits caused by the first and second electrodes overlapping, thus improving the reliability of the battery cell. Moreover, this electrode assembly can have the first insulating element only on a portion of the first electrode and the second insulating element only on a portion of the second electrode, achieving good insulation while also reducing manufacturing costs.

[0141] The technical solutions described in the embodiments of this application are applicable to various electrical devices that use battery cells and battery devices, such as mobile phones, portable devices, laptops, electric vehicles, electric toys, power tools, vehicles, ships and spacecraft, etc. For example, spacecraft include airplanes, rockets, space shuttles and spacecraft.

[0142] For ease of explanation, the following embodiments will use a vehicle as an example of an electrical device.

[0143] Please refer to Figure 1 , Figure 1This is a schematic diagram of the structure of a vehicle 1000 provided in some embodiments of this application. A battery device 100 is disposed inside the vehicle 1000, and the battery device 100 may be located at the bottom, front, or rear of the vehicle 1000. The battery device 100 can be used to power the vehicle 1000; for example, the battery device 100 can serve as the operating power source for the vehicle 1000.

[0144] The vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 is used to control the battery device 100 to supply power to the motor 300, for example, for the power needs of the vehicle 1000 during startup, navigation and driving.

[0145] In some embodiments of this application, the battery device 100 can not only serve as the operating power source for the vehicle 1000, but also as the driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0146] Please refer to Figure 2 , Figure 2 This is an exploded view of a battery device 100 provided in some embodiments of this application. The battery device 100 may include a housing 10 and battery cells 20, the housing 10 being used to house the battery cells 20.

[0147] The housing 10 has an enclosed space inside for accommodating the battery cells 20. The housing 10 can have various structures. In some embodiments, the housing 10 may include a first part 11 and a second part 12, which are interlocked. The first part 11 and the second part 12 can have various shapes, such as cuboids or cylinders. The first part 11 can be a hollow structure open on one side, and the second part 12 can also be a hollow structure open on one side. The open side of the second part 12 interlocks with the open side of the first part 11, thus forming a housing 10 with an enclosed space. Alternatively, the first part 11 can be a hollow structure open on one side, and the second part 12 can be a plate-like structure, with the second part 12 interlocking with the open side of the first part 11, thus forming a housing 10 with an accommodating space.

[0148] In the battery device 100, there can be one or more battery cells 20. If there are multiple battery cells 20, they can be connected in series, parallel, or in a mixed configuration. A mixed configuration means that multiple battery cells 20 are connected in both series and parallel. Alternatively, multiple battery cells 20 can be first connected in series, parallel, or in a mixed configuration to form a battery module, and then multiple battery modules can be connected in series, parallel, or in a mixed configuration to form a whole, which is then housed within the housing 10. Another option is that all battery cells 20 can be directly connected in series, parallel, or in a mixed configuration, and then the whole consisting of all battery cells 20 is housed within the housing 10.

[0149] In some embodiments, the battery device 100 may further include a busbar component, through which multiple battery cells 20 can be electrically connected to each other to achieve series, parallel, or mixed connection of the multiple battery cells 20. The busbar component may be a metallic conductor, such as copper, iron, aluminum, stainless steel, aluminum alloy, etc.

[0150] Please refer to Figure 3 , Figure 4 , Figure 5 and Figure 6 , Figure 3 An exploded view of a battery cell 20 provided in some embodiments of this application. Figure 4 This is a top view schematic diagram of the electrode assembly 22 provided in some embodiments of this application. Figure 5 for Figure 4 A cross-sectional view at position AA. Figure 6 for Figure 4 A cross-sectional view of the BB position. This application provides a battery cell 20, which includes an electrode assembly 22. The electrode assembly 22 includes a first electrode 221, a second electrode 222, and a separator 223. The first electrode 221 and the second electrode 222 have opposite polarities. Along a first direction, the separator 223 is disposed between the first electrode 221 and the second electrode 222. At least one end of the first electrode 221 is provided with a first insulating member 224, and / or at least one end of the second electrode 222 is provided with a second insulating member 225. In a projection plane perpendicular to the first direction, the orthographic projections of all the first insulating members 224 disposed on the first electrode 221 and / or the orthographic projections of all the second insulating members 225 disposed on the second electrode 222 form a ring.

[0151] Battery cell 20 refers to the smallest unit that makes up battery device 100.

[0152] The battery cell 20 includes a housing 21 and an electrode assembly 22, which is housed within the housing 21.

[0153] The housing 21 may include a housing 211 and an end cap 212. The housing 211 has an opening, and the end cap 212 closes the opening of the housing 211. Here, "closed" means covered or shut, and can be either sealed or unsealed.

[0154] End cap 212 refers to a component that covers the opening of housing 211 to isolate the internal environment of battery cell 20 from the external environment. The shape of end cap 212 can be adapted to the shape of housing 211 to fit it. Optionally, end cap 212 can be made of a material with a certain hardness and strength (such as aluminum alloy), so that end cap 212 is less prone to deformation under pressure and impact, enabling battery cell 20 to have higher structural strength and improved reliability. The material of end cap 212 can include, but is not limited to, copper, iron, aluminum, stainless steel, aluminum alloy, and plastic.

[0155] The housing 211 is a component used to cooperate with the end cap 212 to form the internal environment of the battery cell 20. This internal environment can accommodate the electrode assembly 22, electrolyte, and other components. The housing 211 and the end cap 212 can be independent components. An opening can be provided on the housing 211, and the end cap 212 can be used to close the opening to form the internal environment of the battery cell 20. Alternatively, the end cap 212 and the housing 211 can be integrated. Specifically, the end cap 212 and the housing 211 can form a common mating surface before other components are inserted into the housing. When it is necessary to encapsulate the interior of the housing 211, the end cap 212 closes the housing 211. The housing 211 can have various shapes and sizes, such as cuboid, cylindrical, hexagonal prism, etc. Specifically, the shape of the housing 211 can be determined according to the specific shape and size of the electrode assembly 22. The material of the housing 211 can include, but is not limited to, copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0156] In an embodiment where the housing 211 has an opening at one end, one end cap 212 may be provided. In an embodiment where the housing 211 has openings at opposite ends, two end caps 212 may be provided, with the two end caps 212 respectively closing the two openings of the housing 211. The two end caps 212 and the housing 211 together define the receiving space for accommodating the electrode assembly 22.

[0157] Electrode assembly 22 is the component in the battery cell 20 where the electrochemical reaction occurs. The housing 211 may contain one or more electrode assemblies 22. The electrode assembly 22 is mainly formed by stacking a positive electrode sheet, a separator 223, and a negative electrode sheet. The positive electrode sheet includes a positive current collector and a positive active material, with the positive active material coated on the surface of the positive current collector. In some embodiments, the positive current collector also has a portion uncoated with positive active material, protruding from the coated portion, and serving as a positive electrode tab. In other embodiments, the positive electrode tab may be separately disposed from the positive current collector and then electrically connected. The negative electrode sheet includes a negative current collector and a negative active material, with the negative active material coated on the surface of the negative current collector. In some embodiments, the negative electrode current collector further includes a portion uncoated with negative electrode active material, which protrudes from the negative electrode current collector coated with negative electrode active material, and serves as a negative electrode tab. In other embodiments, the negative electrode tab may also be a separate structure from the negative electrode current collector, which is then electrically connected.

[0158] One of the first electrode 221 and the second electrode 222 is a positive electrode, and the other is a negative electrode. For example, when the first electrode 221 is a positive electrode, the second electrode 222 is a negative electrode. Or, when the first electrode 221 is a positive electrode, the second electrode 222 is a negative electrode.

[0159] The first direction is the stacking direction of the first electrode 221, the spacer 223, and the second electrode 222. Please refer to... Figure 5 and Figure 6 The first direction is the Z direction shown in the figure.

[0160] In some embodiments, the separator 223 can be a separator membrane, which can be any known porous separator membrane with good chemical and mechanical stability. In other embodiments, the separator 223 can also be a solid electrolyte layer. Along the first direction, the separator 223 is disposed between the first electrode 221 and the second electrode 222 to isolate the first electrode 221 and the second electrode 222. When the separator 223 is a solid electrolyte layer, it can also function as an ion transporter.

[0161] The first electrode 221 includes multiple ends. Taking a rectangular structure as an example, the first electrode 221 has two opposite ends along its length, located at opposite ends along its length. The first electrode 221 also has two opposite ends along its width, located at opposite ends along its width. The first electrode 221 may have a first insulating member 224 at only one end, or it may have a first insulating member 224 at two ends. When the first electrode has a first insulating member 224 at two ends, it can be two adjacent ends of the first electrode 221, or two opposite ends of the first electrode 221. Of course, the first electrode 221 may also have a first insulating member 224 at three ends, or all ends of the first electrode 221 may have a first insulating member 224. When all ends of the first electrode 221 are provided with a first insulating element 224, all the first insulating elements 224 provided on the first electrode 221 form a ring.

[0162] The first insulating element 224 serves an insulating function. When the end of the first electrode 221 where the first insulating element 224 is located is bent, the first insulating element 224 can insulate and isolate the first electrode 221 and the second electrode 222, thereby reducing the risk of short circuit caused by the first electrode 221 and the second electrode 222 overlapping. The material of the first insulating element 224 can be plastic, rubber, etc.

[0163] The second electrode 222 includes multiple ends. Taking a rectangular structure as an example, the second electrode 222 has two opposite ends along its length, located at opposite ends along its length. The second electrode 222 also has two opposite ends along its width, located at opposite ends along its width. The second electrode 222 may have a second insulating member 225 at only one end, or it may have a second insulating member 225 at both ends. When the first electrode has two ends with a second insulating member 225, it can be two adjacent ends of the second electrode 222, or two opposite ends of the second electrode 222. Of course, the second electrode 222 may also have three ends with a second insulating member 225, or all ends of the second electrode 222 may have a second insulating member 225. When all ends of the second electrode 222 are provided with a second insulating element 225, all the second insulating elements 225 provided on the second electrode 222 form a ring.

[0164] The second insulating element 225 serves as an insulator. When the end of the first electrode 221 without the first insulating element 224 bends, the second insulating element 225 can insulate and isolate the first electrode 221 and the second electrode 222, thereby reducing the risk of short circuit caused by the overlap of the first electrode 221 and the second electrode 222. The material of the second insulating element 225 can be plastic, rubber, etc.

[0165] Please refer to Figure 4 ,exist Figure 4 In the embodiment shown, the orthographic projections of all the first insulating members 224 disposed on the first electrode 221 onto a projection plane perpendicular to the first direction and the orthographic projections of all the second insulating members 225 disposed on the second electrode 222 onto a projection plane perpendicular to the first direction enclose a rectangular ring.

[0166] At least one end of the first electrode 221 is provided with a first insulating member 224, which can cover burrs or molten beads at the end of the first electrode 221, thereby reducing the risk of short circuit caused by burrs or molten beads causing the first electrode 221 and the second electrode 222 to overlap. At least one end of the second electrode 222 is provided with a second insulating member 225, which can cover burrs or molten beads at the end of the second electrode 222, thereby reducing the risk of short circuit caused by burrs or molten beads causing the first electrode 221 and the second electrode 222 to overlap. By forming a ring with the orthographic projections of all the first insulating members 224 on the first electrode 221 in a projection plane perpendicular to the first direction and / or the orthographic projections of all the second insulating members on the second electrode 222 in a projection plane perpendicular to the first direction, the burrs or molten beads at the ends of the first electrode 221 without the first insulating members 224 are not directly covered, but the second insulating members 225 can block the burrs or molten beads at the ends of the first electrode 221 without the first insulating members 224 to a certain extent, thereby reducing the risk of short circuit caused by the burrs or molten beads causing the first electrode 221 and the second electrode 222 to overlap. Similarly, although burrs or molten beads at the end of the second electrode 222 without the second insulating member 225 are not directly covered, the first insulating member 224 can, to a certain extent, block the burrs or molten beads at the end of the second electrode 222 without the second insulating member 225, thereby reducing the risk of short circuits caused by the burrs or molten beads causing the first electrode 221 and the second electrode 222 to overlap, which is beneficial to improving the reliability of the battery cell 20. In addition, when manufacturing the electrode assembly 22, it is necessary to press the first electrode 221, the separator 223 and the second electrode 222 along the first direction. When the end of the first electrode 221 with the first insulating member 224 bends during the pressing process, the first insulating member 224 can play an insulating and isolating role, thereby reducing the risk of short circuits caused by the overlap of the first electrode 221 and the second electrode 222. When the end of the first electrode 221 without the first insulating member 224 bends during extrusion, the second insulating member 225 provides insulation, reducing the risk of short circuit due to the overlap of the first electrode 221 and the second electrode 222, thus improving the reliability of the battery cell 20. Furthermore, the electrode assembly 22 can have the first insulating member 224 only on a portion of the first electrode 221 and the second insulating member 225 only on a portion of the second electrode 222, achieving good insulation while also reducing manufacturing costs.

[0167] In some embodiments, the first insulating element 224 includes a solid electrolyte; and / or the second insulating element 225 includes a solid electrolyte.

[0168] Solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0169] Polymer solid electrolytes can be polyether (polyoxyethylene), polysiloxane, polycarbonate, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, monoionic polymers, polyionic liquids-lithium salts, cellulose, etc.

[0170] Inorganic solid electrolytes may include one or more of the following: oxide solid electrolytes (crystalline perovskite, sodium superconducting ion conductor, garnet, amorphous LiPON thin film), sulfide solid electrolytes (crystalline lithium superconducting ion conductor (lithium germanium phosphate sulfide, silver sulfide germanium ore), amorphous sulfides), halide solid electrolytes, nitride solid electrolytes, and hydride solid electrolytes.

[0171] Composite solid electrolytes are formed by adding inorganic solid electrolyte fillers to polymer solid electrolytes.

[0172] The first insulating element 224 and / or the second insulating element 225 include a solid electrolyte. On the one hand, the solid electrolyte can provide insulation and reduce the risk of short circuit caused by the overlap of the first electrode 221 and the second electrode 222. On the other hand, the solid electrolyte allows ions to pass through. When the first insulating element 224 and / or the second insulating element 225 overlaps between the first electrode 221 and the second electrode 222, the solid electrolyte can form an ion pathway, which helps to reduce the internal resistance of the battery cell 20.

[0173] In some embodiments, the first insulating element 224 is a coating applied to the end of the first electrode 221; and / or the second insulating element 225 is a coating applied to the end of the second electrode 222.

[0174] The first insulating element 224 can be an insulating coating, which is formed by coating the end of the first electrode 221 with an insulating coating and drying it. Optionally, the first insulating element 224 can be a solid electrolyte coating formed by coating a solid electrolyte onto the end of the first electrode 221.

[0175] The second insulating element 225 can be an insulating coating, formed by coating the end of the second electrode 222 with an insulating coating and drying it. Optionally, the second insulating element 225 can be a solid electrolyte coating formed by coating a solid electrolyte onto the end of the second electrode 222.

[0176] The first insulating element 224 is a coating applied to the end of the first electrode 221. On one hand, the first insulating element 224 can better cover burrs or molten beads at the end of the first electrode 221, thereby reducing the risk of a short circuit caused by burrs or molten beads causing the first electrode 221 and the second electrode 222 to overlap. On the other hand, the connection stability between the first insulating element 224 and the first electrode 221 is good; the first insulating element 224 is not easily detached from the first electrode 221, and can stably protect the first electrode 221. Similarly, the second insulating element 225 is a coating applied to the end of the second electrode 222. On the one hand, the second insulating element 225 can better cover burrs or molten beads at the end of the second electrode 222, thereby reducing the risk of a short circuit caused by burrs or molten beads causing the first electrode 221 and the second electrode 222 to overlap. On the other hand, the connection stability between the second insulating member 225 and the second electrode 222 is good, and the second insulating member 225 is not easy to detach from the second electrode 222, thus it can stably play a protective role for the second electrode 222.

[0177] Please refer to Figure 3 , Figure 4 , Figure 5 and Figure 6 In some embodiments, the first electrode 221 has a first insulating member 224 at both ends along the second direction, and the second electrode 222 has a second insulating member 225 at both ends along the third direction. In a projection plane perpendicular to the first direction, the orthographic projections of the two first insulating members 224 located at both ends of the first electrode 221 and the orthographic projections of the two second insulating members 225 located at both ends of the second electrode 222 form a ring. The first direction, the second direction, and the third direction are all perpendicular to each other.

[0178] The second direction and the first direction can form an acute angle or a right angle. Please refer to [reference needed]. Figure 5 and Figure 6 The second direction is the X direction shown in the diagram. In this case, the second direction is perpendicular to the first direction. The third direction can form an acute angle or a right angle with the first direction. Please refer to... Figure 5 and Figure 6 The third direction is the Y direction shown in the figure. At this time, the first direction, the second direction and the third direction are perpendicular to each other.

[0179] First insulating elements 224 are provided at both ends of the first electrode 221 along the second direction, that is, two first insulating elements 224 are respectively provided at both ends of the first electrode 221 along the second direction. The first insulating elements 224 can play an insulating role. When the two ends of the first electrode 221 along the second direction are bent, the first insulating elements 224 can insulate and isolate the first electrode 221 and the second electrode 222, thereby reducing the risk of short circuit caused by the first electrode 221 and the second electrode 222 overlapping.

[0180] The second electrode 222 has two second insulating elements 225 at both ends along the third direction, that is, two second insulating elements 225 are respectively disposed at both ends of the second electrode 222 along the third direction. The second insulating elements 225 can play an insulating role. When the first electrode 221 is bent at both ends along the third direction, the second insulating elements 225 can insulate and isolate the first electrode 221 and the second electrode 222, thereby reducing the risk of short circuit caused by the first electrode 221 and the second electrode 222 overlapping.

[0181] Please refer to Figure 4 ,exist Figure 4In the illustrated embodiment, the orthographic projections of the two first insulating members 224 onto a projection plane perpendicular to the first direction and the orthographic projections of the two second insulating members 225 onto a projection plane perpendicular to the first direction form a rectangular ring. Along the second direction, both ends of the first electrode 221 are provided with first insulating members 224, which can cover burrs or molten beads at the ends of the first electrode 221, thereby reducing the risk of short circuits caused by burrs or molten beads causing the first electrode 221 and the second electrode 222 to overlap. Along the third direction, both ends of the second electrode 222 are provided with second insulating members 225, which can cover burrs or molten beads at the ends of the second electrode 222, thereby reducing the risk of short circuits caused by burrs or molten beads causing the first electrode 221 and the second electrode 222 to overlap. Although the burrs or molten beads at both ends of the first electrode 221 along the third direction are not directly covered, the second insulating member 225 can block the burrs or molten beads at the ends of the first electrode 221 along the third direction to a certain extent, thereby reducing the risk of short circuit caused by the burrs or molten beads causing the first electrode 221 and the second electrode 222 to overlap. Similarly, although the burrs or molten beads at both ends of the second electrode 222 along the second direction are not directly covered, the first insulating member 224 can block the burrs or molten beads at the ends of the second electrode 222 along the second direction to a certain extent, thereby reducing the risk of short circuit caused by the burrs or molten beads causing the first electrode 221 and the second electrode 222 to overlap, which is beneficial to improving the reliability of the battery cell 20. Furthermore, during the manufacturing of the electrode assembly 22, the first electrode 221, the separator 223, and the second electrode 222 need to be extruded along a first direction. When the two ends of the first electrode 221 along the second direction bend during the extrusion process, the first insulating member 224 can provide insulation and isolation, thereby reducing the risk of short circuit caused by the overlap of the first electrode 221 and the second electrode 222. When the two ends of the first electrode 221 along a third direction bend during the extrusion process, the second insulating member 225 can provide insulation and isolation, thereby reducing the risk of short circuit caused by the overlap of the first electrode 221 and the second electrode 222, which is beneficial to improving the reliability of the battery cell 20. Moreover, the electrode assembly 22 can only have the first insulating member 224 at the two ends of the first electrode 221 along the second direction and the second insulating member 225 at the two ends of the second electrode 222 along the third direction, which has a good insulation effect while also having a lower manufacturing cost.

[0182] Please refer to Figure 7 , Figure 7 This is a cross-sectional view of a first electrode 221 provided for some embodiments of this application. In some embodiments, the first electrode 221 includes a first current collector 2211 and a first active material layer 2212, the first active material layer 2212 being disposed on at least one side of the first current collector 2211 along a first direction. A first insulating member 224 covers one end of the first current collector 2211 along a second direction.

[0183] When the first electrode 221 is a positive electrode, the first current collector 2211 is the aforementioned positive current collector, and the first active material layer 2212 is the aforementioned coating formed by the positive active material coated on the surface of the positive current collector. When the first electrode 221 is a negative electrode, the first current collector 2211 is the aforementioned negative current collector, and the first active material layer 2212 is the aforementioned coating formed by the negative active material coated on the surface of the negative current collector.

[0184] The first active material layer 2212 can be provided only on one side of the first current collector 2211 along the first direction, or the first active material layer 2212 can be provided on both sides of the first current collector 2211 along the first direction.

[0185] The first insulating element 224 at least covers one end of the first current collector 2211 along the second direction. The two first insulating elements 224 respectively cover both ends of the first current collector 2211 along the second direction.

[0186] The burrs or molten beads at the end of the first electrode 221 along the second direction are mainly present on the first current collector 2211. By covering one end of the first current collector 2211 along the second direction with the first insulating member 224, the burrs or molten beads at the end of the first electrode 221 can be effectively covered, thereby reducing the risk of short circuit caused by the burrs or molten beads causing the first electrode 221 and the second electrode 222 to overlap, which is beneficial to improving the reliability of the battery cell 20.

[0187] Please refer to Figure 8 , Figure 8 This is a cross-sectional view of the first electrode 221 provided in some other embodiments of this application. In other embodiments, the first insulating member 224 covers one end of the first active material layer 2212 along a second direction.

[0188] The first insulating element 224 not only covers one end of the first current collector 2211 along the second direction, but also covers one end of the first active material layer 2212 along the second direction. In other words, both ends of the first current collector 2211 along the second direction are covered by two first insulating elements 224, and both ends of the first active material layer 2212 along the second direction are covered by the aforementioned two first insulating elements 224.

[0189] By covering one end of the first active material layer 2212 along the second direction with the first insulating member 224, on the one hand, burrs or molten beads at the end of the first electrode 221 can be better covered, thereby reducing the risk of short circuit caused by the first electrode 221 and the second electrode 222 overlapping due to burrs or molten beads. On the other hand, when the two ends of the first electrode 221 along the second direction are bent during the extrusion process, the first insulating member 224 can play an insulating role, reducing the risk of short circuit caused by the first active material layer 2212 contacting the second electrode 222, which is beneficial to improving the reliability of the battery cell 20.

[0190] Please refer to Figure 9 , Figure 9 This is a cross-sectional view of a first electrode 221 provided in some embodiments of this application. In some embodiments, a first active material layer 2212 is provided on both sides of the first current collector 2211 along a first direction. The first insulating member 224 includes a first insulating portion 2241, a second insulating portion 2242, and a third insulating portion 2243. The second insulating portion 2242 connects the first insulating portion 2241 and the third insulating portion 2243, and covers one end of the first current collector 2211 along a second direction and one end of the first active material layer 2212 along the second direction. Along the first direction, the first insulating portion 2241 is located on the side of one first active material layer 2212 opposite to the first current collector 2211, and the third insulating portion 2243 is located on the side of another first active material layer 2212 opposite to the first current collector 2211.

[0191] The first electrode 221 includes two first active material layers 2212, which are respectively disposed on both sides of the first current collector 2211 along the first direction.

[0192] The first insulating portion 2241 and the third insulating portion 2243 are disposed opposite each other along a first direction. The end of the first electrode 221 along a second direction is disposed between the first insulating portion 2241 and the third insulating portion 2243. In other words, along the first direction, the first current collector 2211 and the two first active material layers 2212 are both located between the first insulating portion 2241 and the third insulating portion 2243. The second insulating portion 2242 connects the first insulating portion 2241 and the third insulating portion 2243, and covers one end of the first current collector 2211 along the second direction and one end of the two first active material layers 2212 along the second direction.

[0193] The first insulating part 2241, the second insulating part 2242 and the third insulating part 2243 together form a U-shaped structure, which covers the end of the first electrode 221 along the second direction to protect the end of the first electrode 221 along the second direction.

[0194] The first insulating portion 2241, the second insulating portion 2242, and the third insulating portion 2243 can completely cover the end of the first electrode 221 along the second direction, better covering the burrs or molten beads at the end of the first electrode 221, thereby reducing the risk of short circuit caused by the burrs or molten beads causing the first electrode 221 and the second electrode 222 to overlap. Furthermore, along the first direction, the first insulating portion 2241 is located on the side of a first active material layer 2212 facing away from the first current collector 2211. The first insulating portion 2241 can protect the side of the first active material layer 2212 facing away from the first current collector 2211, thereby reducing the risk of short circuit caused by the first active material layer 2212 contacting the second electrode 222. The third insulating portion 2243 is located on the side of another first active material layer 2212 facing away from the first current collector 2211. The third insulating portion 2243 can protect the side of the other first active material layer 2212 facing away from the first current collector 2211, thereby reducing the risk of short circuit caused by the other first active material layer 2212 contacting the second electrode 222, which is beneficial to improving the reliability of the battery cell 20.

[0195] Please refer to Figure 10 , Figure 10 This is a cross-sectional view of a second electrode 222 provided in some embodiments of this application. In some embodiments, the second electrode 222 includes a second current collector 2221 and a second active material layer 2222, the second active material layer 2222 being disposed on at least one side of the second current collector 2221 along a first direction. A second insulating member 225 covers one end of the second current collector 2221 along a third direction.

[0196] When the second electrode 222 is a positive electrode, the second current collector 2221 is the aforementioned positive current collector, and the second active material layer 2222 is the aforementioned coating formed by the positive active material coated on the surface of the positive current collector. When the second electrode 222 is a negative electrode, the second current collector 2221 is the aforementioned negative current collector, and the second active material layer 2222 is the aforementioned coating formed by the negative active material coated on the surface of the negative current collector.

[0197] The second active material layer 2222 can be provided only on one side of the second current collector 2221 along the first direction, or the second active material layer 2222 can be provided on both sides of the second current collector 2221 along the first direction.

[0198] The second insulating element 225 covers at least one end of the second current collector 2221 along the third direction. The two second insulating elements 225 respectively cover both ends of the second current collector 2221 along the third direction.

[0199] The burrs or molten beads at the third-direction end of the second electrode 222 are mainly present on the second current collector 2221. By covering one end of the second current collector 2221 with the second insulating member 225, the burrs or molten beads at the end of the second electrode 222 can be effectively covered, thereby reducing the risk of short circuit caused by the burrs or molten beads causing the first electrode 221 and the second electrode 222 to overlap, which is beneficial to improving the reliability of the battery cell 20.

[0200] Please refer to Figure 11 , Figure 11 This is a cross-sectional view of the second electrode 222 provided for other embodiments of this application. In other embodiments, the second insulating member 225 covers one end of the second active material layer 2222 along a third direction.

[0201] The second insulating member 225 not only covers one end of the second current collector 2221 along the third direction, but also covers one end of the second active material layer 2222 along the third direction. In other words, both ends of the second current collector 2221 along the third direction are covered by two second insulating members 225, and both ends of the second active material layer 2222 along the third direction are covered by the aforementioned two second insulating members 225.

[0202] By covering one end of the second active material layer 2222 along the third direction with the second insulating member 225, on the one hand, burrs or molten beads at the end of the second electrode 222 can be better covered, thereby reducing the risk of short circuit caused by the first electrode 221 and the second electrode 222 overlapping due to burrs or molten beads. On the other hand, when the two ends of the first electrode 221 along the third direction are bent during the extrusion process, the second insulating member 225 can play an insulating role, reducing the risk of short circuit caused by the second active material layer 2222 contacting the first electrode 221, which is beneficial to improving the reliability of the battery cell 20.

[0203] Please refer to Figure 12 , Figure 12 This is a cross-sectional view of the second electrode 222 provided in some embodiments of this application. In some embodiments, along a first direction, a second active material layer 2222 is provided on both sides of the second current collector 2221. The second insulating member 225 includes a fourth insulating portion 2251, a fifth insulating portion 2252, and a sixth insulating portion 2253. The fifth insulating portion 2252 connects the fourth insulating portion 2251 and the sixth insulating portion 2253, and covers one end of the second current collector 2221 along a third direction and one end of the second active material layer 2222 along a third direction. Along the first direction, the fourth insulating portion 2251 is located on the side of one second active material layer 2222 facing away from the second current collector 2221, and the sixth insulating portion 2253 is located on the side of the other second active material layer 2222 facing away from the second current collector 2221.

[0204] The second electrode 222 includes two second active material layers 2222, which are respectively disposed on both sides of the second current collector 2221 along the first direction.

[0205] The fourth insulating portion 2251 and the sixth insulating portion 2253 are disposed opposite each other along a first direction. The end of the second electrode 222 along a third direction is disposed between the fourth insulating portion 2251 and the sixth insulating portion 2253. In other words, along the first direction, the second current collector 2221 and the two second active material layers 2222 are both located between the fourth insulating portion 2251 and the sixth insulating portion 2253. The fifth insulating portion 2252 connects the fourth insulating portion 2251 and the sixth insulating portion 2253, and covers one end of the second current collector 2221 along a third direction and one end of the two second active material layers 2222 along a third direction.

[0206] The fourth insulating part 2251, the fifth insulating part 2252 and the sixth insulating part 2253 together form a U-shaped structure, which covers the end of the second electrode 222 along the third direction to protect the end of the second electrode 222 along the third direction.

[0207] The fourth insulating part 2251, the fifth insulating part 2252 and the sixth insulating part 2253 can completely cover the end of the second electrode 222 along the third direction, better covering the burrs or molten beads at the end of the second electrode 222, thereby reducing the risk of short circuit caused by the first electrode 221 and the second electrode 222 overlapping due to burrs or molten beads. Furthermore, along the first direction, the fourth insulating portion 2251 is located on the side of a second active material layer 2222 that is away from the second current collector 2221. The fourth insulating portion 2251 can protect the side of the second active material layer 2222 that is away from the second current collector 2221, thereby reducing the risk of short circuit caused by the second active material layer 2222 contacting the first electrode 221. The sixth insulating portion 2253 is located on the side of another second active material layer 2222 that is away from the second current collector 2221. The sixth insulating portion 2253 can protect the side of the other second active material layer 2222 that is away from the second current collector 2221, thereby reducing the risk of short circuit caused by the other second active material layer 2222 contacting the first electrode 221. This is beneficial to improving the reliability of the battery cell 20.

[0208] Please refer to this again. Figure 4 In some embodiments, the first electrode 221 is provided with a first tab 226, which is connected to one end of the first electrode 221 along a second direction. And / or the second electrode 222 is provided with a second tab 227, which is connected to one end of the second electrode 222 along a third direction.

[0209] First insulating members 224 are provided at both ends of the first electrode 221 along the second direction. A first tab 226 is connected to one end of the first electrode 221 along the second direction. Thus, the first insulating member 224 is provided at the end of the first electrode 221 where the first tab 226 is located, and also at the other end opposite to the end where the first tab 226 is located. When the first insulating member 224 is provided, it can cover the ends of the first current collector 2211 and the first active material layer 2212 along the second direction, while avoiding the location of the first tab 226 on the first current collector 2211. In short, the first insulating member 224 is provided on the first electrode 221 to avoid the first tab 226.

[0210] Second insulating members 225 are provided at both ends of the second electrode 222 along a third direction. A second tab 227 is connected to one end of the second electrode 222 along a third direction. Thus, the second electrode 222 has a second insulating member 225 at the end where the second tab 227 is located, and also at the opposite end. When the second insulating member 225 is provided, it covers the ends of the second current collector 2221 and the second active material layer 2222 along a third direction, while avoiding the location of the second tab 227 on the second current collector 2221. In short, the second insulating member 225 on the second electrode 222 avoids the second tab 227.

[0211] First insulating members 224 are provided at both ends of the first electrode 221 along the second direction, and first tabs 226 are connected to one end of the first electrode 221 along the second direction. Thus, the first electrode 221 has a first insulating member 224 at the end where the first tab 226 is provided, and also at the other end opposite to the end where the first tab 226 is provided. When the first tab 226 is manufactured by die-cutting, the first insulating member 224 can cover the die-cut side of the first electrode 221, thereby shielding burrs or molten beads generated during die-cutting and reducing the risk of short circuits caused by burrs or molten beads colliding between the first electrode 221 and the second electrode 222. The second electrode 222 has a second insulating member 225 at both ends along the third direction. The second tab 227 is connected to one end of the second electrode 222 along the third direction. Thus, the second electrode 222 has a second insulating member 225 at the end where the second tab 227 is located, and also at the other end opposite to the end where the second tab 227 is located. When the second tab 227 is manufactured by die-cutting, the second insulating member 225 can cover the die-cut side of the second electrode 222, thereby shielding burrs or molten beads generated during die-cutting and reducing the risk of short circuit caused by burrs or molten beads causing the first electrode 221 and the second electrode 222 to overlap.

[0212] Please refer to Figure 13 , Figure 13 This is a top view schematic diagram of the electrode assembly 22 provided in other embodiments of this application. In other embodiments, the first electrode 221 is provided with a first tab 226, which is connected to one end of the first electrode 221 along a third direction. And / or the second electrode 222 is provided with a second tab 227, which is connected to one end of the second electrode 222 along a second direction.

[0213] The first electrode 221 is provided with a first insulating member 224 at both ends along the second direction, and the first electrode tab 226 is connected to one end of the first electrode 221 along the third direction. Thus, the first insulating member 224 and the first electrode tab 226 are provided at different positions of the first electrode 221.

[0214] The second electrode 222 is provided with a second insulating member 225 at both ends along the third direction, and the second electrode tab 227 is connected to one end of the second electrode 222 along the second direction. Thus, the second insulating member 225 and the second electrode tab 227 are provided at different positions of the second electrode 222.

[0215] When the first insulating member 224 and the first tab 226 are positioned at different locations on the first electrode 221, the first insulating member 224 can cover the slit side of the first electrode 221, thereby shielding the burrs or molten beads generated during slitting and reducing the risk of short circuit caused by the burrs or molten beads causing the first electrode 221 and the second electrode 222 to overlap. When the second insulating member 225 and the second tab 227 are positioned at different locations on the second electrode 222, the second insulating member 225 can cover the slit side of the second electrode 222, thereby shielding the burrs or molten beads generated during slitting and reducing the risk of short circuit caused by the burrs or molten beads causing the first electrode 221 and the second electrode 222 to overlap.

[0216] In some embodiments, the first electrode 221 includes a first current collector 2211, the first current collector 2211 and the first tab 226 are integrally formed; and / or the second electrode 222 includes a second current collector 2221, the second current collector 2221 and the second tab 227 are integrally formed.

[0217] When the first current collector 2211 and the first electrode 226 are integrally formed, the first current collector 2211 and the first electrode 226 are an integral structure. For example, the first electrode 226 can be formed on the first current collector 2211 by die-cutting the electrode, so that the first current collector 2211 and the first electrode 226 are integrally formed.

[0218] When the second current collector 2221 and the second tab 227 are integrally formed, the second current collector 2221 and the second tab 227 are an integral structure. For example, the second tab 227 can be formed on the second current collector 2221 by die-cutting the tab, so that the second current collector 2221 and the second tab 227 are integrally formed.

[0219] The first current collector 2211 and the first tab 226 are integrally formed, resulting in better overall integrity and higher connection strength between them. This also helps reduce the internal resistance of the battery cell 20. Similarly, the second current collector 2221 and the second tab 227 are integrally formed, again exhibiting better overall integrity and higher connection strength. This further helps reduce the internal resistance of the battery cell 20.

[0220] In some other embodiments, the first tab 226 is welded to the first electrode 221, and the second tab 227 is welded to the second electrode 222.

[0221] In some embodiments, the first electrode 221 is provided with a first insulating member 224 at both ends along a third direction; and / or the second electrode 222 is provided with a second insulating member 225 at both ends along a second direction.

[0222] The first electrode 221 has a first insulating element 224 at both ends along the second direction, and the first electrode 221 also has a first insulating element 224 at both ends along the third direction. In this way, the first electrode 221 is completely covered by the first insulating element 224, which further reduces the risk of short circuit caused by contact between the first electrode 221 and the second electrode 222.

[0223] The second electrode 222 has second insulating members 225 at both ends along the second direction, and also at both ends along the third direction. In this way, the second electrode 222 is completely covered by the second insulating members 225, which further reduces the risk of short circuit due to contact between the first electrode 221 and the second electrode 222.

[0224] First insulating elements 224 are provided at both ends of the first electrode 221 along the second direction and at both ends of the first electrode 221 along the third direction. Thus, the first insulating elements 224 can completely cover the first electrode 221, providing better insulation. Second insulating elements 225 are provided at both ends of the second electrode 222 along the second direction and at both ends of the second electrode 222 along the third direction. Thus, the second insulating elements 225 can completely cover the second electrode 222, providing better insulation.

[0225] Please refer to Figure 4 , Figure 5 and Figure 6 In some embodiments, the first electrode 221 is a negative electrode, and both ends of the first electrode 221 extend beyond the second electrode 222 along the second direction, with each end extending beyond the second electrode 222 by a length L1, satisfying: 0.1mm ≤ L1 ≤ 10mm. And / or both ends of the first electrode 221 extend beyond the second electrode 222 along the third direction, with each end extending beyond the second electrode 222 by a length L2, satisfying: 0.1mm ≤ L2 ≤ 10mm.

[0226] The first electrode 221 is the negative electrode, and the second electrode 222 is the positive electrode. Along the second direction, both ends of the first electrode 221 extend beyond the second electrode 222.

[0227] L1 represents the length of the first electrode 221 extending beyond the second electrode 222 along the second direction. It should be noted that the length of one end of the first electrode 221 extending beyond the second electrode 222 along the second direction can be equal to the length of the other end of the first electrode 221 extending beyond the second electrode 222 along the second direction. Alternatively, the length of one end of the first electrode 221 extending beyond the second electrode 222 along the second direction can be unequal to the length of the other end of the first electrode 221 extending beyond the second electrode 222 along the second direction. However, the length of one end of the first electrode 221 extending beyond the second electrode 222 along the second direction is within the range of 0.1 to 10 mm, and the length of the other end of the first electrode 221 extending beyond the second electrode 222 along the second direction is also within the range of 0.1 to 10 mm.

[0228] The length of the first electrode 221 extending beyond the second electrode 222 along the second direction can be: L1 = 0.1mm, 0.2mm, 0.5mm, 1mm, 1.5mm, 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, etc.

[0229] L2 represents the length of the first electrode 221 extending beyond the second electrode 222 along a third direction. It should be noted that the length of one end of the first electrode 221 extending beyond the second electrode 222 along a third direction can be equal to the length of the other end of the first electrode 221 extending beyond the second electrode 222 along a third direction. Alternatively, the length of one end of the first electrode 221 extending beyond the second electrode 222 along a third direction can be unequal to the length of the other end of the first electrode 221 extending beyond the second electrode 222 along a third direction. However, the length of one end of the first electrode 221 extending beyond the second electrode 222 along a third direction is within the range of 0.1 to 10 mm, and the length of the other end of the first electrode 221 extending beyond the second electrode 222 along a third direction is also within the range of 0.1 to 10 mm.

[0230] The length of the first electrode 221 extending beyond the second electrode 222 along a third direction can be: L2 = 0.1mm, 0.2mm, 0.5mm, 1mm, 1.5mm, 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, etc.

[0231] When L1 ≥ 0.1 mm, the length of the first electrode 221 extending beyond the second electrode 222 along the second direction is relatively large, which helps reduce assembly difficulty, achieves an overhang design, and reduces the risk of metal ion precipitation. When L1 ≤ 10 mm, the length of the first electrode 221 extending beyond the second electrode 222 along the second direction is not excessive, which helps reduce the volume of the electrode assembly 22, improves the internal space utilization of the battery cell 20, and increases the energy density of the battery cell 20. Therefore, when 0.1 mm ≤ L1 ≤ 10 mm, it can both reduce assembly difficulty and achieve an overhang design, and also improve the energy density of the battery cell 20. When L2 ≥ 0.1 mm, the length of the first electrode 221 extending beyond the second electrode 222 along the third direction is relatively large, which helps reduce assembly difficulty, achieves an overhang design, and reduces the risk of metal ion precipitation. When L2 ≤ 10 mm, the length of the first electrode 221 extending beyond the second electrode 222 along a third direction is not excessive, which helps to reduce the volume of the electrode assembly 22, improve the internal space utilization of the battery cell 20, and increase the energy density of the battery cell 20. Therefore, when 0.1 mm ≤ L2 ≤ 10 mm, it can both reduce the assembly difficulty and realize the overhang design, and improve the energy density of the battery cell 20.

[0232] Optionally, 0.3mm≤L1≤3mm, and / or 0.3mm≤L2≤3mm.

[0233] The length of the first electrode 221 extending beyond the second electrode 222 along the second direction can be: L1 = 0.3mm, 0.5mm, 0.8mm, 1mm, 1.2mm, 1.5mm, 1.8mm, 2mm, 2.2mm, 2.5mm, 2.8mm, 3mm, etc.

[0234] The length of the first electrode 221 extending beyond the second electrode 222 along a third direction can be: L2 = 0.3mm, 0.5mm, 0.8mm, 1mm, 1.2mm, 1.5mm, 1.8mm, 2mm, 2.2mm, 2.5mm, 2.8mm, 3mm, etc.

[0235] When L1 ≥ 0.3 mm, the length of the first electrode 221 extending beyond the second electrode 222 along the second direction is greater, which is more conducive to reducing assembly difficulty and realizing an overhang design, thus reducing the risk of metal ion precipitation. When L1 ≤ 3 mm, the length of the first electrode 221 extending beyond the second electrode 222 along the second direction is not too large, which is conducive to reducing the volume of the electrode assembly 22, improving the internal space utilization of the battery cell 20, and increasing the energy density of the battery cell 20. Therefore, when 0.3 mm ≤ L1 ≤ 3 mm, it is possible to reduce assembly difficulty, realize an overhang design, and increase the energy density of the battery cell 20. When L2 ≥ 0.3 mm, the length of the first electrode 221 extending beyond the second electrode 222 along the third direction is greater, which is more conducive to reducing assembly difficulty and realizing an overhang design, thus reducing the risk of metal ion precipitation. When L2 ≤ 3mm, the length of the first electrode 221 extending beyond the second electrode 222 along a third direction is not excessive, which helps to reduce the volume of the electrode assembly 22, improve the internal space utilization of the battery cell 20, and increase the energy density of the battery cell 20. Therefore, when 0.3mm ≤ L2 ≤ 3mm, it is possible to reduce assembly difficulty, achieve overhang design, and improve the energy density of the battery cell 20.

[0236] In some embodiments, the separator 223 is a solid electrolyte layer.

[0237] When the separator 223 is a solid electrolyte layer, the battery cell 20 is a solid battery cell 20 with a high energy density.

[0238] Please refer to Figures 4 to 13 This application embodiment also provides an electrode assembly 22, which includes a first electrode 221, a second electrode 222, and an isolator 223. The first electrode 221 and the second electrode 222 have opposite polarities. Along a first direction, the isolator 223 is disposed between the first electrode 221 and the second electrode 222. At least one end of the first electrode 221 is provided with a first insulating member 224 and / or at least one end of the second electrode 222 is provided with a second insulating member 225. In a projection plane perpendicular to the first direction, the orthographic projections of all the first insulating members 224 disposed on the first electrode 221 and / or the orthographic projections of all the second insulating members 225 disposed on the second electrode 222 form a ring.

[0239] In some embodiments, the first insulating element 224 includes a solid electrolyte; and / or the second insulating element 225 includes a solid electrolyte.

[0240] The first insulating element 224 and / or the second insulating element 225 include a solid electrolyte. On the one hand, the solid electrolyte can provide insulation and reduce the risk of short circuit caused by the overlap of the first electrode 221 and the second electrode 222. On the other hand, the solid electrolyte allows ions to pass through. When the first insulating element 224 and / or the second insulating element 225 overlaps between the first electrode 221 and the second electrode 222, the solid electrolyte can form an ion pathway, which helps to reduce the internal resistance of the battery cell 20.

[0241] Please refer to Figure 4 In some embodiments, the first electrode 221 has a first insulating member 224 at both ends along the second direction, and the second electrode 222 has a second insulating member 225 at both ends along the third direction. In a projection plane perpendicular to the first direction, the orthographic projections of the two first insulating members 224 located at both ends of the first electrode 221 and the orthographic projections of the two second insulating members 225 located at both ends of the second electrode 222 form a ring. The first direction, the second direction, and the third direction are all perpendicular to each other.

[0242] Along the second direction, both ends of the first electrode 221 are provided with a first insulating member 224. The first insulating member 224 can cover the burrs or molten beads at the ends of the first electrode 221, thereby reducing the risk of short circuit caused by the burrs or molten beads causing the first electrode 221 and the second electrode 222 to overlap. Along the third direction, both ends of the second electrode 222 are provided with a second insulating member 225. The second insulating member 225 can cover the burrs or molten beads at the ends of the second electrode 222, thereby reducing the risk of short circuit caused by the burrs or molten beads causing the first electrode 221 and the second electrode 222 to overlap. Although the burrs or molten beads at both ends of the first electrode 221 along the third direction are not directly covered, the second insulating member 225 can block the burrs or molten beads at the ends of the first electrode 221 along the third direction to a certain extent, thereby reducing the risk of short circuit caused by the burrs or molten beads causing the first electrode 221 and the second electrode 222 to overlap. Similarly, although the burrs or molten beads at both ends of the second electrode 222 along the second direction are not directly covered, the first insulating member 224 can, to a certain extent, block the burrs or molten beads at the ends of the second electrode 222 along the second direction, thereby reducing the risk of short circuits caused by the burrs or molten beads causing the first electrode 221 and the second electrode 222 to overlap, which is beneficial to improving the reliability of the battery cell 20. In addition, when manufacturing the electrode assembly 22, it is necessary to extrude the first electrode 221, the separator 223, and the second electrode 222 along the first direction. When the two ends of the first electrode 221 along the second direction bend during the extrusion process, the first insulating member 224 can play an insulating role, thereby reducing the risk of short circuits caused by the overlap of the first electrode 221 and the second electrode 222. When the two ends of the first electrode 221 along the third direction bend during the extrusion process, the second insulating member 225 can play an insulating role, thereby reducing the risk of short circuits caused by the overlap of the first electrode 221 and the second electrode 222, which is beneficial to improving the reliability of the battery cell 20. Furthermore, the electrode assembly 22 can have a first insulating element 224 provided only at both ends of the first electrode 221 along the second direction, and a second insulating element 225 provided at both ends of the second electrode 222 along the third direction, which achieves good insulation effect while also reducing manufacturing cost.

[0243] Please refer to Figure 4 In some embodiments, the first electrode 221 is provided with a first tab 226, which is connected to one end of the first electrode 221 along a second direction. The second electrode 222 is provided with a second tab 227, which is connected to one end of the second electrode 222 along a third direction.

[0244] First insulating members 224 are provided at both ends of the first electrode 221 along the second direction, and first tabs 226 are connected to one end of the first electrode 221 along the second direction. Thus, the first electrode 221 has a first insulating member 224 at the end where the first tab 226 is provided, and also at the other end opposite to the end where the first tab 226 is provided. When the first tab 226 is manufactured by die-cutting, the first insulating member 224 can cover the die-cut side of the first electrode 221, thereby shielding burrs or molten beads generated during die-cutting and reducing the risk of short circuits caused by burrs or molten beads colliding between the first electrode 221 and the second electrode 222. The second electrode 222 has a second insulating member 225 at both ends along the third direction. The second tab 227 is connected to one end of the second electrode 222 along the third direction. Thus, the second electrode 222 has a second insulating member 225 at the end where the second tab 227 is located, and also at the other end opposite to the end where the second tab 227 is located. When the second tab 227 is manufactured by die-cutting, the second insulating member 225 can cover the die-cut side of the second electrode 222, thereby shielding burrs or molten beads generated during die-cutting and reducing the risk of short circuit caused by burrs or molten beads causing the first electrode 221 and the second electrode 222 to overlap.

[0245] In some embodiments, the separator 223 is a solid electrolyte layer.

[0246] When the separator 223 is a solid electrolyte layer, it is beneficial to reduce the volume of the electrode assembly 22 and improve the energy density.

[0247] Please refer to Figure 14 , Figure 14 This is a schematic block diagram illustrating an electrode assembly manufacturing method 30 provided in some embodiments of this application. Embodiments of this application also provide an electrode assembly manufacturing method 30, which includes:

[0248] Step S100: Provide the first electrode 221;

[0249] Step S200: Provide a second electrode 222, the second electrode 222 having the opposite polarity to the first electrode 221, at least one end of the first electrode 221 being provided with a first insulating member 224, and / or at least one end of the second electrode 222 being provided with a second insulating member 225;

[0250] Step S300: Provide isolation component 223;

[0251] Step S400: The first electrode 221, the insulating member 223, and the second electrode 222 are stacked along the first direction, such that the insulating member 223 is disposed between the first electrode 221 and the second electrode 222 along the first direction. In the projection plane perpendicular to the first direction, the orthographic projections of all the first insulating members 224 disposed on the first electrode 221 and / or the orthographic projections of all the second insulating members 225 disposed on the second electrode 222 form a ring.

[0252] In step S100, the first electrode 221 may have a first insulating member 224 at only one end, or it may have a first insulating member 224 at two ends, or it may have a first insulating member 224 at three ends, or it may have a first insulating member 224 at all ends.

[0253] In step S200, the second electrode 222 may have a second insulating member 225 at only one end, or it may have a second insulating member 225 at two ends, or it may have a second insulating member 225 at three ends, or it may have a second insulating member 225 at all ends.

[0254] In step S300, the separator 223 can be a separator membrane or a solid electrolyte layer.

[0255] In step S400, the first electrode 221, the separator 223, and the second electrode 222 are stacked along a first direction, forming a stacked structure. The separator 223 is disposed between the first electrode 221 and the second electrode 222 along the first direction to isolate the first electrode 221 and the second electrode 222. When the separator 223 is a solid electrolyte layer, it can also function as an ion transporter. The orthographic projections of all the first insulating members 224 disposed on the first electrode 221 onto a projection plane perpendicular to the first direction and / or the orthographic projections of all the second insulating members 225 disposed on the second electrode 222 onto a projection plane perpendicular to the first direction form a rectangular ring.

[0256] Please refer to Figure 15 In some embodiments, the first electrode 221 has a first insulating member 224 at both ends along the second direction, and the second electrode 222 has a second insulating member 225 at both ends along the third direction. In a projection plane perpendicular to the first direction, the orthographic projections of the two first insulating members 224 located at both ends of the first electrode 221 and the orthographic projections of the two second insulating members 225 located at both ends of the second electrode 222 form a ring. The first direction, the second direction, and the third direction are mutually perpendicular. The first electrode 221 includes:

[0257] Step S110: Provide the first electrode strip;

[0258] Step S120: Apply insulating coating to both ends of the first electrode strip in the width direction;

[0259] Step S130: Cut the first electrode strip into multiple first electrode sheets 221.

[0260] The first electrode strip may include multiple consecutively arranged first electrodes 221, that is, the first electrode strip is the strip of multiple first electrodes 221 before they are cut.

[0261] Optionally, the first electrode strip is provided with a plurality of first electrode tabs 226, and the first electrode tabs 226 are correspondingly provided with the first electrode 221. In this way, after step S130, each first electrode 221 is provided with a corresponding first electrode tab 226.

[0262] In step S120, an insulating coating is formed by coating both ends of the first electrode strip in the width direction. After step S130, the insulating coating is cut into the first insulating element 224 on the first electrode 221.

[0263] In step S130, the cutting direction of the cutter is parallel to the width direction of the first electrode strip, that is, the cutter cuts the first electrode strip along the width direction of the first electrode strip to cut the first electrode strip into multiple first electrodes 221.

[0264] By coating insulating slurry at both ends of the first electrode strip in the width direction, and then cutting the first electrode strip into multiple first electrodes 221, multiple first electrodes 221 can be manufactured at one time, which helps to improve the manufacturing efficiency of the first electrodes 221 and reduce the manufacturing cost of the electrode assembly 22.

[0265] Please refer to Figure 16 In some embodiments, providing the first electrode strip includes:

[0266] Step S111: Provide the first electrode substrate;

[0267] Step S112: Cut the first electrode substrate into multiple first electrode blanks;

[0268] Step S113: Die-cut the tabs on the first electrode blank to form the first electrode strip.

[0269] The first electrode substrate can be a first electrode roll formed after the first active material layer 2212 is coated on the first current collector 2211. In step S112, the first electrode substrate is cut into multiple first electrode blanks.

[0270] In step S113, the first electrode blank is die-cut with tabs to form the first electrode strip. Thus, the first electrode strip has multiple first tabs 226, and the first tabs 226 are correspondingly set with the first electrode 221.

[0271] By slitting the first electrode substrate, multiple first electrode blanks can be formed. Die-cutting the first electrode blanks with tabs can form the first electrode strip. Using the above manufacturing method can improve the manufacturing efficiency of the first electrode strip and reduce the manufacturing cost of the electrode assembly 22.

[0272] Please refer to Figure 17 , Figure 17 A schematic block diagram of an electrode assembly manufacturing method 30 provided for further embodiments of this application. In some embodiments, providing the second electrode 222 includes:

[0273] Step S210: Provide the second electrode strip;

[0274] Step S220: Apply insulating coating to both ends of the second electrode strip in the width direction;

[0275] Step S230: Cut the second electrode strip into multiple second electrode sheets 222.

[0276] The second electrode strip may include multiple consecutively arranged second electrodes 222, that is, the second electrode strip is the strip of multiple second electrodes 222 before they are cut.

[0277] Optionally, the second electrode strip is provided with a plurality of second electrode tabs 227, and the second electrode tabs 227 are correspondingly provided with the second electrode 222. In this way, after step S230, each second electrode 222 is provided with a corresponding second electrode tab 227.

[0278] In step S220, an insulating coating is formed by coating both ends of the second electrode strip in the width direction. After step S230, the insulating coating is cut into the second insulating element 225 on the second electrode 222.

[0279] In step S230, the cutting direction of the cutter is parallel to the width direction of the second electrode strip, that is, the cutter cuts the second electrode strip along the width direction of the second electrode strip to cut the second electrode strip into multiple second electrodes 222.

[0280] By coating insulating slurry at both ends of the second electrode strip in the width direction, and then cutting the second electrode strip into multiple second electrodes 222, multiple second electrodes 222 can be manufactured at one time, which helps to improve the manufacturing efficiency of the second electrodes 222 and reduce the manufacturing cost of the electrode assembly 22.

[0281] Please refer to Figure 18 , Figure 18 This application also provides schematic block diagrams of an electrode assembly manufacturing method 30 according to some embodiments. In some embodiments, providing the second electrode strip includes:

[0282] Step S211: Provide a second electrode substrate;

[0283] Step S212: Cut the second electrode substrate into multiple second electrode blanks;

[0284] Step S213: Die-cut the tabs on the second electrode blank to form the second electrode strip.

[0285] The second electrode substrate can be a roll of second electrode material formed after coating the second current collector 2221 with the second active material layer 2222. In step S212, the second electrode substrate is slit to form multiple second electrode blanks.

[0286] In step S213, the tabs are die-cut on the second electrode blank to form the second electrode strip. Thus, there are multiple second tabs 227 on the second electrode strip, and the second tabs 227 are correspondingly set with the second electrode 222.

[0287] By slitting the second electrode substrate, multiple second electrode blanks can be formed. Die-cutting the electrode tabs into the second electrode blanks will form the second electrode strip. Using the above manufacturing method will help improve the manufacturing efficiency of the second electrode strip and reduce the manufacturing cost of the electrode assembly 22.

[0288] In some embodiments, the insulating coating includes a solid electrolyte.

[0289] The insulating coating includes a solid electrolyte. On the one hand, the solid electrolyte can act as an insulation barrier, reducing the risk of short circuits caused by the overlap of the first electrode 221 and the second electrode 222. On the other hand, the solid electrolyte allows ions to pass through. When the first insulating member 224 and / or the second insulating member 225 overlaps between the first electrode 221 and the second electrode 222, the solid electrolyte can form an ion pathway, which helps to reduce the internal resistance of the battery cell 20.

[0290] Please refer to Figure 19 , Figure 19 This is a schematic block diagram of an electrode assembly manufacturing method 30 provided for further embodiments of this application. In some embodiments, the separator 223 is a solid electrolyte layer. After the step of stacking the first electrode 221, the separator 223, and the second electrode 222 along a first direction, the electrode assembly manufacturing method 30 further includes:

[0291] Step S500: Perform isostatic pressing on the stacked first electrode 221, spacer 223 and second electrode 222.

[0292] The working principle of isostatic pressure is based on Pascal's law: "In a closed container, the pressure of a medium (liquid or gas) can be transmitted equally in all directions."

[0293] In step S500, the encapsulation bag containing the stacked first electrode 221, the separator 223, and the second electrode 222 can be placed into the hydraulic oil, and then the hydraulic oil can be pressurized to achieve isostatic pressure treatment.

[0294] When the separator 223 is a solid electrolyte layer, it is beneficial to reduce the volume of the electrode assembly 22 and improve the energy density. By performing isostatic pressing on the stacked first electrode 221, separator 223 and second electrode 222, it is beneficial to achieve densification of the electrode assembly 22 and further reduce the volume of the electrode assembly 22.

[0295] This application embodiment also provides a battery device 100, which includes the aforementioned battery cell 20.

[0296] This application embodiment also provides an electrical device, which includes the aforementioned battery cell 20, and the battery cell 20 is used to provide electrical energy to the electrical device.

[0297] According to some embodiments of this application, please refer to Figures 3 to 13 .

[0298] This application provides a battery cell 20, which includes an electrode assembly 22. The electrode assembly 22 includes a first electrode 221, a second electrode 222, a separator 223, a first insulator 224, and a second insulator 225. The first electrode 221 and the second electrode 222 have opposite polarities. Along a first direction, the separator 223 is disposed between the first electrode 221 and the second electrode 222. The first electrode 221 has a first insulator 224 at both ends along a second direction. The second electrode 222 has a second insulator 225 at both ends along a third direction. In a projection plane perpendicular to the first direction, the orthographic projections of the two first insulators 224 located at both ends of the first electrode 221 and the orthographic projections of the two second insulators 225 located at both ends of the second electrode 222 form a ring. The first direction, the second direction, and the third direction are all perpendicular to each other. Along the second direction, both ends of the first electrode 221 are provided with a first insulating member 224. The first insulating member 224 can cover the burrs or molten beads at the ends of the first electrode 221, thereby reducing the risk of short circuit caused by the burrs or molten beads causing the first electrode 221 and the second electrode 222 to overlap. Along the third direction, both ends of the second electrode 222 are provided with a second insulating member 225. The second insulating member 225 can cover the burrs or molten beads at the ends of the second electrode 222, thereby reducing the risk of short circuit caused by the burrs or molten beads causing the first electrode 221 and the second electrode 222 to overlap. Although the burrs or molten beads at both ends of the first electrode 221 along the third direction are not directly covered, the second insulating member 225 can block the burrs or molten beads at the ends of the first electrode 221 along the third direction to a certain extent, thereby reducing the risk of short circuit caused by the burrs or molten beads causing the first electrode 221 and the second electrode 222 to overlap. Similarly, although the burrs or molten beads at both ends of the second electrode 222 along the second direction are not directly covered, the first insulating member 224 can, to a certain extent, block the burrs or molten beads at the ends of the second electrode 222 along the second direction, thereby reducing the risk of short circuits caused by the burrs or molten beads causing the first electrode 221 and the second electrode 222 to overlap, which is beneficial to improving the reliability of the battery cell 20. In addition, when manufacturing the electrode assembly 22, it is necessary to extrude the first electrode 221, the separator 223, and the second electrode 222 along the first direction. When the two ends of the first electrode 221 along the second direction bend during the extrusion process, the first insulating member 224 can play an insulating role, thereby reducing the risk of short circuits caused by the overlap of the first electrode 221 and the second electrode 222. When the two ends of the first electrode 221 along the third direction bend during the extrusion process, the second insulating member 225 can play an insulating role, thereby reducing the risk of short circuits caused by the overlap of the first electrode 221 and the second electrode 222, which is beneficial to improving the reliability of the battery cell 20.Furthermore, the electrode assembly 22 can have first insulating members 224 provided only at both ends of the first electrode 221 along the second direction, and second insulating members 225 provided at both ends of the second electrode 222 along the third direction. This achieves good insulation while reducing manufacturing costs. By forming a ring with the orthographic projections of the two first insulating members 224 onto a plane perpendicular to the first direction and the two second insulating members 225 onto a plane perpendicular to the first direction, the first insulating members 224 and the second insulating members 225 can work together to achieve better insulation, further reducing the risk of short circuits caused by the overlap of the first electrode 221 and the second electrode 222, and thus improving the reliability of the battery cell 20.

[0299] The first insulating element 224 includes a solid electrolyte; and / or the second insulating element 225 includes a solid electrolyte. The solid electrolyte in the first insulating element 224 and / or the second insulating element 225 provides insulation, reducing the risk of short circuits caused by the overlap of the first electrode 221 and the second electrode 222. Furthermore, the solid electrolyte allows ions to pass through; when the first insulating element 224 and / or the second insulating element 225 overlaps between the first electrode 221 and the second electrode 222, the solid electrolyte forms an ion pathway, which helps reduce the internal resistance of the battery cell 20.

[0300] The separator 223 is a solid electrolyte layer. When the separator 223 is a solid electrolyte layer, the battery cell 20 is a solid battery cell 20, which has a higher energy density.

[0301] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A battery cell, characterized by, Includes an electrode assembly, the electrode assembly comprising: A first electrode, a second electrode, and a separator, wherein the first electrode and the second electrode have opposite polarities and are disposed between the first electrode and the second electrode along a first direction; A first insulating element is provided at at least one end of the first electrode, the first insulating element comprising a solid electrolyte; and / or The second insulating element is provided at at least one end of the second electrode, and the second insulating element includes a solid electrolyte. In a projection plane perpendicular to the first direction, the orthographic projections of all the first insulating elements disposed on the first electrode and / or the orthographic projections of all the second insulating elements disposed on the second electrode form a ring.

2. The battery cell of claim 1, wherein, The first insulating element is a coating applied to the end of the first electrode; and / or The second insulating element is a coating applied to the end of the second electrode.

3. The battery cell of claim 1, wherein, The first electrode is provided with the first insulating element at both ends along the second direction, and the second electrode is provided with the second insulating element at both ends along the third direction; In a projection plane perpendicular to the first direction, the orthographic projections of the two first insulating members located at both ends of the first electrode plate and the orthographic projections of the two second insulating members located at both ends of the second electrode plate form a ring. The first direction, the second direction, and the third direction are perpendicular to each other.

4. The battery cell of claim 3, wherein, The first electrode includes a first current collector and a first active material layer, wherein the first active material layer is disposed on at least one side of the first current collector along the first direction; The first insulating element covers one end of the first current collector along the second direction.

5. The battery cell of claim 4, wherein, The first insulating element covers one end of the first active material layer along the second direction.

6. The battery cell of claim 5, wherein, Along the first direction, the first active material layer is provided on both sides of the first current collector; The first insulating member includes a first insulating portion, a second insulating portion, and a third insulating portion. The second insulating portion connects the first insulating portion and the third insulating portion. The second insulating portion covers one end of the first current collector along the second direction and one end of the first active material layer along the second direction. Along the first direction, the first insulating portion is located on one side of the first active material layer away from the first current collector, and the third insulating portion is located on another side of the first active material layer away from the first current collector.

7. The battery cell of claim 3, wherein the cathode comprises a lithium metal oxide. The second electrode includes a second current collector and a second active material layer, wherein the second active material layer is disposed on at least one side of the second current collector along the first direction; The second insulating element covers one end of the second current collector along the third direction.

8. The battery cell of claim 7, wherein the cathode comprises a lithium metal oxide. The second insulating element covers one end of the second active material layer along the third direction.

9. The battery cell of claim 8, wherein the cathode comprises a lithium metal oxide. Along the first direction, the second active material layer is provided on both sides of the second current collector; The second insulating member includes a fourth insulating portion, a fifth insulating portion, and a sixth insulating portion. The fifth insulating portion connects the fourth insulating portion and the sixth insulating portion. The fifth insulating portion covers one end of the second current collector along the third direction and one end of the second active material layer along the third direction. Along the first direction, the fourth insulating portion is located on one side of the second active material layer away from the second current collector, and the sixth insulating portion is located on the other side of the second active material layer away from the second current collector.

10. The battery cell of claim 3, wherein, The first electrode is provided with a first tab, which is connected to one end of the first electrode along the second direction; and / or The second electrode is provided with a second tab, which is connected to one end of the second electrode along the third direction.

11. The battery cell of claim 3, wherein, The first electrode is provided with a first tab, which is connected to one end of the first electrode along the third direction; and / or The second electrode is provided with a second tab, which is connected to one end of the second electrode along the second direction.

12. The battery cell of claim 10 or 11, wherein, The first electrode includes a first current collector, the first current collector and the first electrode tab are integrally formed; and / or The second electrode includes a second current collector, and the second current collector and the second electrode tab are integrally formed.

13. The battery cell according to any one of claims 3-11, characterized in that, The first insulating element is provided at both ends of the first electrode along a third direction; and / or The second electrode is provided with the second insulating element at both ends along the second direction.

14. The battery cell of any one of claims 3-11, wherein, The first electrode is a negative electrode. Both ends of the first electrode extend beyond the second electrode along the second direction, and the length by which each end extends beyond the second electrode is L1, satisfying: 0.1mm ≤ L1 ≤ 10mm; and / or The first electrode extends beyond the second electrode at both ends along the third direction, and the length of each end extending beyond the second electrode is L2, satisfying: 0.1mm≤L2≤10mm.

15. The battery cell of claim 14, wherein the cathode comprises a lithium metal oxide. 0.3mm≤L1≤3mm, and / or 0.3mm≤L2≤3mm.

16. The battery cell of any one of claims 1-11, wherein, The insulating component is a solid electrolyte layer.

17. An electrode assembly, characterized by include: A first electrode, a second electrode, and a separator, wherein the first electrode and the second electrode have opposite polarities and are disposed between the first electrode and the second electrode along a first direction; A first insulating element is provided at at least one end of the first electrode, the first insulating element comprising a solid electrolyte; and / or The second insulating element is provided at at least one end of the second electrode, and the second insulating element includes a solid electrolyte. In a projection plane perpendicular to the first direction, the orthographic projections of all the first insulating elements disposed on the first electrode and / or the orthographic projections of all the second insulating elements disposed on the second electrode form a ring.

18. The electrode assembly of claim 17, wherein, The first electrode is provided with the first insulating element at both ends along the second direction, and the second electrode is provided with the second insulating element at both ends along the third direction; In a projection plane perpendicular to the first direction, the orthographic projections of the two first insulating members located at both ends of the first electrode plate and the orthographic projections of the two second insulating members located at both ends of the second electrode plate form a ring. The first direction, the second direction, and the third direction are perpendicular to each other.

19. The electrode assembly of claim 18, wherein, The first electrode is provided with a first electrode tab, which is connected to one end of the first electrode along the second direction; The second electrode is provided with a second tab, which is connected to one end of the second electrode along the third direction.

20. The electrode assembly of any of claims 17-19, wherein, The insulating component is a solid electrolyte layer.

21. A battery device, characterized in that, Includes the battery cell according to any one of claims 1-16.

22. An electrical device, comprising: Includes a battery cell according to any one of claims 1-16, the battery cell being used to provide electrical energy to the electrical device.

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