Abstract: A positive electrode sheet includes a current collector including a coating region and a non-coating region, a resistance layer disposed on the current collector and including a conductive agent, a first binder, and a first positive electrode active material, and a positive electrode active material layer including a second positive electrode active material, a conductive agent, and a second binder. A resistance of the resistance layer is greater than a resistance of the positive electrode active material layer. In a cross section of the positive electrode sheet, a projection of at least a part of the positive electrode active material layer on the current collector and a projection of the resistance layer on the current collector do not overlap. A polarization parameter P of the positive electrode sheet is in a range of 0.4-65.0 and equals ((1?S)/S)·(R1/R2).

Abstract: An electrode assembly includes a positive electrode plate and a negative electrode plate wound or stacked to form a bend region, and a barrier layer provided at the bend region. At least part of the barrier layer is located between the positive electrode plate and the negative electrode plate that are adjacent to each other, and is configured to prevent at least part of ions deintercalated from the positive electrode plate from being intercalated into the negative electrode plate in the bend region. A ratio of a thickness of the barrier layer to a porosity of the barrier layer is larger than or equal to 3.5 microns and smaller than or equal to 2000 microns.

Abstract: An electrode assembly includes a positive electrode plate and a negative electrode plate wound or stacked to form a bend region, and a barrier layer provided at the bend region. At least part of the barrier layer is located between the positive electrode plate and the negative electrode plate that are adjacent to each other, and is configured to prevent at least part of ions deintercalated from the positive electrode plate from being intercalated into the negative electrode plate in the bend region.

Abstract: Provided are a separator for a secondary battery and a preparation method therefor, and a secondary battery including the separator, a battery module, a battery pack, and a power consuming device. The separator for a secondary battery of the present application includes a substrate layer and a nanofiber layer provided on one surface of the substrate layer. The nanofiber layer includes a lithium supplementing agent, a polymer, and an optional conductive material; and in the total weight of the nanofiber layer, the content of the lithium supplementing agent accounts for 30.0-50.0% by weight, the content of the polymer accounts for 50.0-70.0% by weight, and the content of the conductive material accounts for 0-5.0% by weight.

Abstract: This application discloses a negative electrode plate, a preparation method thereof, a secondary battery, a battery module, a battery pack, and an electric apparatus. The negative electrode plate may include a negative electrode current collector and a negative electrode film layer, where the negative electrode film layer may be provided on at least one surface of the negative electrode current collector and may include a negative electrode active material; where at least part of surface of the negative electrode active material may be provided with an artificial solid electrolyte interface film, where the artificial solid electrolyte interface film may include a first inorganic lithium salt, and the first inorganic lithium salt may be selected from one or two of Li2CO3 and Li2SO3.

Abstract: A positive electrode sheet includes a current collector including a coating region and a non-coating region, a resistance layer disposed on the current collector and including a conductive agent, a first binder, and a first positive electrode active material, and a positive electrode active material layer including a second positive electrode active material, a conductive agent, and a second binder. A resistance of the resistance layer is greater than a resistance of the positive electrode active material layer. In a cross section of the positive electrode sheet, a projection of at least a part of the positive electrode active material layer on the current collector and a projection of the resistance layer on the current collector do not overlap. A polarization parameter P of the positive electrode sheet is in a range of 0.4-65.0 and equals ((1?S)/S)·(R1/R2).

Abstract: An electrode assembly includes a positive electrode plate and a negative electrode plate wound or stacked to form a bend region, and a barrier layer provided at the bend region. At least part of the barrier layer is located between the positive electrode plate and the negative electrode plate that are adjacent to each other, and is configured to prevent at least part of ions deintercalated from the positive electrode plate from being intercalated into the negative electrode plate in the bend region.

Abstract: The present disclosure provides a lithium-ion battery, which comprises: a positive electrode plate containing a positive electrode active material, a negative electrode plate containing a negative electrode active material and an electrolyte. The positive electrode active material comprises: a core and a coating layer coating a surface of the core and comprising boron. The electrolyte comprises a lithium salt, a non-aqueous organic solvent and an electrolyte additive, the electrolyte additive comprises an organic titanium compound. The coating layer of the positive electrode active material of the lithium-ion battery according to the present disclosure contains boron, and the electrolyte of the lithium-ion battery contains the organic titanium compound, under the combined effect of the coating layer containing boron and the electrolyte containing the organic titanium compound, the lithium-ion battery has excellent high temperature cycle performance and excellent high temperature storage performance.

Abstract: The present application relates to the technical field of lithium-ion batteries and, specifically, relates to an electrolyte and a lithium-ion battery containing the electrolyte. The electrolyte of the present application comprises an organic solvent, a lithium salt and an additive, wherein the additive contains a cyanosulfone compound and a lithium fluorophosphate compound. When the electrolyte contains both the cyanosulfone compound and the lithium fluorophosphate at the same time, the cyanosulfone compound will form a passive film on the surface of the electrode of a high-voltage battery, so as to effectively suppress reaction between the electrolyte and the electrode, further, the lithium fluorophosphate can effectively suppress the decomposition of the lithium salt and improve the film resistance of the electrode. Under the synergistic effect of the two, the cycle performance of the lithium-ion battery is greatly improved, and the storage performance of the electrolyte is also significantly improved.

Abstract: The present disclosure provides a lithium-ion battery, which comprises: a positive electrode plate containing a positive electrode active material, a negative electrode plate containing a negative electrode active material and an electrolyte. The positive electrode active material comprises: a core and a coating layer coating a surface of the core and comprising boron. The electrolyte comprises a lithium salt, a non-aqueous organic solvent and an electrolyte additive, the electrolyte additive comprises an organic titanium compound. The coating layer of the positive electrode active material of the lithium-ion battery according to the present disclosure contains boron, and the electrolyte of the lithium-ion battery contains the organic titanium compound, under the combined effect of the coating layer containing boron and the electrolyte containing the organic titanium compound, the lithium-ion battery has excellent high temperature cycle performance and excellent high temperature storage performance.

Abstract: The present application relates to the technical field of lithium-ion batteries and, specifically, relates to an electrolyte and a lithium-ion battery containing the electrolyte. The electrolyte of the present application comprises an organic solvent, a lithium salt and an additive, wherein the additive contains a cyanosulfone compound and a lithium fluorophosphate compound. When the electrolyte contains both the cyanosulfone compound and the lithium fluorophosphate at the same time, the cyanosulfone compound will form a passive film on the surface of the electrode of a high-voltage battery, so as to effectively suppress reaction between the electrolyte and the electrode, further, the lithium fluorophosphate can effectively suppress the decomposition of the lithium salt and improve the film resistance of the electrode. Under the synergistic effect of the two, the cycle performance of the lithium-ion battery is greatly improved, and the storage performance of the electrolyte is also significantly improved.