Abstract: A positive electrode active material and a preparation method therefor, a positive electrode plate, a battery, and an electrical apparatus. The positive electrode active material includes a transition metal oxide and a coating layer. The coating layer is coated on at least part of the surface of the transition metal oxide. The coating layer includes a silicon-containing polymer. The silicon-containing polymer is formed by polymerizing a silane monomer derivative containing a first group and polysiloxane containing a second group. The first group is reactive with the second group. The molecular weight of the silane monomer derivative is less than that of the polysiloxane.

Abstract: An end cap assembly, a battery cell, a battery, an electrical device, and a method and device for manufacturing a battery cell are provided. The end cap assembly includes an end cap and a pressure relief mechanism. The pressure relief mechanism is connected to the end cap. The pressure relief mechanism is configured to: keep in a first pressure relief state when an internal pressure or temperature of the battery cell is greater than or equal to a first threshold and less than a second threshold, so as to release the internal pressure of the battery cell; and keep in a second pressure relief state when the internal pressure or temperature of the battery cell is greater than or equal to the second threshold, so as to release the internal pressure of the battery cell.

Abstract: Embodiments of this application provide a cell, a battery, and an electric device. The cell includes: an electrode lead-out portion, configured to lead out electric energy of the cell; an electrode assembly, including a main body and a tab, the tab including a transition portion and a connecting portion, where the transition portion is connected between the connecting portion and the main body, and the connecting portion is connected to the electrode lead-out portion to form a connecting region; and an insulation component, where the insulation component includes a first insulator fixed to the main body and a third insulator fixed to the connecting portion, and the insulation component further includes a second insulator connected between the first insulator and the third insulator, where a part of the tab from a first joint to a second joint is not fixed to the insulation component.

Abstract: A battery cell, a battery, an electric device, and a processing method for a battery cell are provided. The battery cell comprises an electrode assembly and active structures. The electrode assembly comprises a positive electrode sheetand a negative electrode sheet, wherein the positive electrode sheet comprises first straight segments and first bent segments, and the negative electrode sheet comprises second straight segments and second bent segments, the first straight segmentsand the second straight segments are alternately stacked to form straight portions, and the first bent segments and the second bent segments are alternately stacked to form corner portions. At least some of the active structures are provided between the first bent segments and the second bent segments adjacent to the inner sides of the first bent segments. In this way, the problem of ion precipitation at the corner portions can be solved.

Abstract: A jelly roll battery cell, a battery, a battery assembly and an electric device. The jelly roll battery cell includes a main body portion and a tab portion; one side of each positive winding portion in one part of positive winding portions is connected to one positive tab, and one side of each positive winding portion in the other part of the positive winding portions is connected to two positive tabs; and/or, one side of each negative winding portion in one part of negative winding portions is connected to one negative tab, and one side of each negative winding portion in the other part of the negative winding portions is connected to two negative tabs.

Abstract: A battery cell comprises an electrode assembly, a case and an insulating member. The case is used for accommodating the electrode assembly and has a wall portion arranged opposite the electrode assembly in a first direction, the wall portion being provided with a first pressure-relief area. In the first direction, the insulating member is at least partially arranged between the electrode assembly and the wall portion to insulate and isolate the electrode assembly from the wall portion. The insulating member is provided with a second pressure-relief area at the position corresponding to the first pressure-relief area, and the first pressure-relief area and the second pressure-relief area are configured to be open when the battery cell releases pressure.

Abstract: The present application relates to the technical field of batteries, and in particular, to a battery electrode plate, an electrode plate assembly, a battery, and an electrical device. The battery electrode plate of the present application comprises a current collector, at least one surface of the current collector being provided with a first coating area, the first coating area being provided with an active material layer, and the active material layer comprising a first active material layer, a second active material layer, and a third active material layer that are connected sequentially from top to bottom along the height direction of the current collector, wherein the attenuation speed of the active material of the second active material layer is smaller than that of the active material in any one of the first active material layer and the third active material layer.

Abstract: A battery cell includes a housing; and a first electrode assembly group and a second electrode assembly group that are accommodated within the housing, where the first electrode assembly group and the second electrode assembly group are arranged along a first direction, the first electrode assembly group and the second electrode assembly group each include at least one electrode assembly, and electrode terminals of the first electrode assembly group and electrode terminals of the second electrode assembly group are respectively located on two walls of the housing that are disposed opposite along the first direction.

Abstract: An embodiment of the present application provides a battery cell, a battery and an electrical device. The battery cell includes: a case, which is a hollow structure having a first opening end; an end cover assembly for covering the first opening end; an electrode assembly accommodated in the case; and an insulating guard layer disposed between the electrode assembly and the case to wrap at least part of the electrode assembly, wherein the insulating guard layer includes a main body portion and a protrusion structure, the main body portion has a second opening end facing the first opening end, the protrusion structure is connected to the second opening end and extends toward the end cover assembly, and the protrusion structure is used for connecting with the end cover assembly.

Abstract: An embodiment of the present application provides a battery cell, a battery and an electrical device. The battery cell includes: a case, which is a hollow structure having a first opening end; an end cover assembly for covering the first opening end; an electrode assembly accommodated in the case; and an insulating guard layer disposed between the electrode assembly and the case to wrap at least part of the electrode assembly, wherein the insulating guard layer includes a main body portion and a protrusion structure, the main body portion has a second opening end facing the first opening end, the protrusion structure is connected to the second opening end and extends toward the end cover assembly, and the protrusion structure is used for connecting with the end cover assembly.

Abstract: An end cap assembly, a battery cell, a battery, an electrical device, and a method and device for manufacturing a battery cell are provided. The end cap assembly includes an end cap and a pressure relief mechanism. The pressure relief mechanism is connected to the end cap. The pressure relief mechanism is configured to: keep in a first pressure relief state when an internal pressure or temperature of the battery cell is greater than or equal to a first threshold and less than a second threshold, so as to release the internal pressure of the battery cell; and keep in a second pressure relief state when the internal pressure or temperature of the battery cell is greater than or equal to the second threshold, so as to release the internal pressure of the battery cell.