Abstract: Lithium replenishing spaces are disposed on a current collection structure, such that the lithium replenishing spaces communicate with an active layer on one side; and the battery is replenished with lithium by using lithium replenishing agents in the lithium replenishing spaces to offset an irreversible lithium consumption in a cycle process, so as to increase the total capacity and the energy density of the battery. According to the present application, due to average weights MA of corresponding active materials in different distribution regions on the active layer, a sum V0 of internal volumes of lithium replenishing spaces corresponding to each of the distribution regions is controlled in a positively correlated manner based on a change in the average weights of the active materials in the different distribution regions.

Abstract: A battery cell may include an electrode assembly and a buffer pad, where the electrode assembly may include a main body portion and a tab extending from the main body portion, the main body portion may include a first main body region and a second main body region, and the thickness of the first main body region along a first direction (T) may be smaller than the thickness of the second main body region along the first direction (T); and where the buffer pad may include a compressible first side wall, the first side wall may include a first buffer portion and a second buffer portion, the thickness of the first buffer portion along the first direction (T) may be greater than the thickness of the second buffer portion along the first direction, and the buffer pad may be provided on a side face of the main body portion.

Abstract: A compound electrode sheet includes two single electrode sheets, and each single electrode sheet includes a current collector and an active material layer. The current collector is provided with a main body and a protrusion portion, and the protrusion portion is arranged protruding out of the main body in an extension direction of the current collector. The active material layer is arranged on a surface of the main body. The protrusion portions of the two current collectors of the two single electrode sheets are fixedly connected. The active material layers of the two single electrode sheets are arranged opposite to each other.

Abstract: A secondary battery includes a negative electrode plate. A negative electrode active material layer of the negative electrode plate includes a porous carbon material. The negative electrode active material layer has a pore. The pore runs through or not through the negative electrode active material layer. Lithium metal is present in the pore.

Abstract: Provided are an electrode assembly, a method and system for manufacturing the same, a battery cell, a battery, and an electric apparatus. The electrode assembly includes an electrode member wound along a winding direction, the electrode member includes an electrode body, and the electrode body includes an insulating matrix and a conductive layer disposed on the insulating matrix; and the conductive layer includes a first part coated with an active substance layer and a second part coated with no active substance layer; the second part is provided in a quantity of N, and the N second parts are spaced apart in the winding direction; and in the winding direction, distance between the Mth and (M-1)th second parts is L1., and distance between the Mth and (M+1)th second parts is L2, where both N and M are positive integers, 2 ? M ? N-1, and 0.95 < L2/L1 < 1.05.

Abstract: An electrode plate and a method for preparing the electrode plate, a secondary battery, a battery module, a battery pack, and an electric apparatus are described. The electrode plate includes a current collector and an active substance layer provided on at least one surface of the current collector. The active substance layer includes an active main material and a porous material. The active substance layer has pores, where the pore runs through or not through the active substance layer. Thickness of the active substance layer is x, and distance between two end openings of the pore in a direction perpendicular to the active substance layer is y, where x and y satisfy the following condition: 0.1?x?y?x.

Abstract: A secondary battery, a battery module, a battery pack, and an electrical device are provided. The secondary battery includes a negative electrode plate, a positive electrode plate, and a separator located between the negative electrode plate and the positive electrode plate. The negative electrode plate or the separator includes a safety coating. A negative electrode charge capacity Nc and a positive electrode charge capacity Pc of the secondary battery satisfy: 0.45?Nc/Pc<1, and/or, a negative electrode discharge capacity Nd and a positive electrode discharge capacity Pd of the secondary battery satisfy: 0.45?Nd/Pd<1. By setting the values of Nc/Pc and/or Nd/Pd and disposing the safety coating in the secondary battery, this application achieves good cycle performance and safety performance while maintaining a high energy density of the secondary battery.

Abstract: A lithium ion secondary battery and a preparation method therefor, a battery module, a battery pack, and a device are provided. In some embodiments, the lithium ion secondary battery comprises a positive electrode plate, a negative electrode plate and an electrolyte, wherein the positive electrode plate comprises a positive electrode active material and a positive electrode lithium-supplementing material comprising a lithium-rich metal oxide, and the lithium-rich metal oxide comprises one or more elements of Ni, Co, Fe, Mn, and Cu; the electrolyte comprises an electrolyte lithium salt and a solvent, and has a percentage ? of the total mass of a fluorine element in the anions of the electrolyte lithium salt relative to the total mass of the electrolyte of <14%.

Abstract: A method for recovering activity of a battery includes obtaining a battery state-of-health value of the battery during a charging process, applying an activation voltage to the battery in response to the battery state-of-health value being less than or equal to a first preset threshold such that lithium ions at a lithium supplement agent of the battery are released to an electrolyte solution, and stopping application of the activation voltage and continuing a normal charge-discharge cycle in response to the battery state-of-health value increasing to be greater than or equal to a second preset threshold. The activation voltage is higher than a normal charging voltage of the battery.

Abstract: Provided in the present application is a negative electrode plate, a secondary battery, a battery module, a battery pack and a power consuming device. The negative electrode plate may comprise a first coating, a second coating and a current collector, the current collector being on one side of the second coating, the first coating being on the other side of the second coating, the first coating and the second coating each comprising a silicon-based material, wherein a molar ratio of element O to element Si of the silicon-based material in the first coating may be 0.5 to 1.5, and a molar ratio of element O to element Si of the silicon-based material in the second coating may be less than or equal to 0.3.

Abstract: A secondary battery includes a positive electrode, a negative electrode, and an electrolyte. The positive electrode includes a positive-electrode active substance layer, the positive-electrode active substance layer contains a pre-lithiation agent, and a molecular formula of the pre-lithiation agent is LixNiaCu1?a?bMbO2, where 1?x?2, 0<a<1, and 0?b <0.1, and M is selected from one or more of Zn, Sn, Mg, Fe, and Mn. The negative electrode includes a negative-electrode active substance layer including graphite and silicon-containing material. The electrolyte contains fluoroethylene carbonate (FEC). A weight percentage of the pre-lithiation agent in the positive-electrode active substance layer, a weight percentage of silicon content in the negative-electrode active substance layer, and a weight percentage of FEC in the electrolyte satisfy 0.2×WSi?WFEC?7.5%?0.6×WL.

Abstract: A secondary battery includes a positive electrode, a negative electrode, and an electrolyte. The positive electrode includes a positive-electrode active substance layer, the positive-electrode active substance layer contains a pre-lithiation agent, and a molecular formula of the pre-lithiation agent is LixNiaCu1?a?bMbO2, where 1?x?2, 0<a<1, and 0?b <0.1, and M is selected from one or more of Zn, Sn, Mg, Fe, and Mn. The negative electrode includes a negative-electrode active substance layer including graphite and silicon-containing material. The electrolyte contains fluoroethylene carbonate (FEC). A weight percentage of the pre-lithiation agent in the positive-electrode active substance layer, a weight percentage of silicon content in the negative-electrode active substance layer, and a weight percentage of FEC in the electrolyte satisfy 0.2×WSi?WFEC?7.5%-0.6×WL.