Abstract: The present application provides a layer-built tab, which includes a plurality of metal pieces and adhesives, the metal pieces being stacked and bonded by the adhesives. The metal pieces are stacked and spaced apart from each other, which increases the heat dissipation area of the tab while supporting a large current flow, the heat dissipation capability of the tab is improved. An electrode plate, a battery core, and a battery including the layer-built tab are also disclosed.

Abstract: A wound electrode assembly, including a first electrode plate including a first current collector and a second electrode plate including a second current collector, wherein the second electrode plate includes a second empty foil segment, the second empty foil segment surrounds the first electrode plate, the second empty foil segment is configured as a tail segment of the second electrode plate, in the second empty foil segment, a surface of the second current collector opposite to the first electrode plate is coated with active substance, a surface of the second current collector away from the first electrode plate is coated with the active substance. The wound electrode assembly to effectively avoids lithium dendrite while improving the utilization of the battery material and the energy density of the battery, thereby improving the safety performance of the battery.

Abstract: The present invention provides a secondary battery. The secondary battery comprises a first electrode tab and a first electrode plate. The first electrode plate first electrode plate comprises a first current collector, a first active layer, a first electrode tab receiving groove and a first electrode plate notch. The first active layer is disposed on a surface of the first current collector. The first electrode tab receiving groove is configured to receive the first electrode tab, and the first electrode tab is electrically connected with the first current collector through the first electrode tab receiving groove. The first electrode plate notch is disposed on an edge of the first electrode tab receiving groove.

Abstract: An electrochemical device includes a cathode, an anode and a separator, the separator being disposed between the cathode and the anode, the separator including a porous substrate and a porous layer, and the porous layer being disposed on a surface of the porous substrate and including inorganic particles and a binder, where a ratio of a puncture elongation of the porous substrate to a puncture force of the porous substrate is about 1.5 mm/N to about 25 mm/N. A lithium-ion battery including the separator, provided by the present application, improves the safety performance of the lithium-ion battery.

Abstract: An anode material includes silicon-containing particles including a silicon composite substrate and an oxide MeOy layer, wherein the oxide MeOy layer is coated on at least a portion of the silicon composite substrate, wherein Me includes at least one of Al, Si, Ti, Mn, V, Cr, Co or Zr, and y is 0.5 to 3; and wherein the oxide MeOy layer includes a carbon material. The anode material has good cycle performance, and the battery prepared from the anode material has better rate performance and lower swelling rate.

Abstract: The present application relates to a negative electrode composite material and preparation thereof and a lithium ion battery. The negative electrode composite material comprises an active material, a metal oxide on the surface of the active material, wherein the ratio of the specific surface area of the negative electrode composite material to the specific surface area of the active material is 1-7. The present application improves the volume energy density and safety performance of a lithium ion battery by selecting a ratio of a specific surface area of the negative electrode composite material to the active material.

Abstract: The present application provides an electrode, an electrochemical device, and an electronic device. The electrode includes: a current collector; a first active material layer including a first active material; and a second active material layer including a second active material; wherein the first active material layer is arranged between the current collector and the second active material layer. The first active material layer is formed on a surface of the current collector, and a particle size of 90% accumulative volume of the first active material is less than 40 ?m. The active material layer is used in the present application to ensure that the electrochemical device and the electronic device do not generate a short circuit when pressed by an external force, thereby ensuring the mechanical safety performance of the electrochemical device and the electronic device.

Abstract: An electrochemical device includes a positive electrode, a negative electrode, a separator located between the positive electrode and the negative electrode, and an electrolytic solution. The positive electrode includes a positive current collector and a positive active material layer disposed on the positive current collector. The positive active material layer includes a positive active material. The positive active material includes an element A. The element A is selected from at least one of Al, B, Ca, Mg, Ti, Cu, Nb, Si, Zr, Y, or W. The electrolytic solution includes at least one of 1,3-propane sultone or a derivative thereof. A mass ratio of the element A in the positive active material to 1,3-propane sultone or a derivative is 1:0.2 to 1:50.

Abstract: The present application relates to an anode electrode and an electrochemical device containing the same. The anode electrode comprises: a current collector, including a first surface and a second surface opposite to the first surface; an insulation layer being disposed on a peripheral portion of the first surface and/or a peripheral portion of the second surface; and a protection layer being disposed on the insulation layer and covering the first surface and/or the second surface. According to an embodiment of the present application, the insulation layer and the protection layer are disposed in the anode electrode of the electrochemical device to construct a seal cavity, which defines a space of the deposition of lithium metal on the anode electrode, thereby resolving the safety problem caused by the irregular deposition of the lithium metal.

Abstract: A positive electrode material includes a lithium composite oxide, and the positive electrode material comprises stress relief particles. There are cavities inside the stress relief particles, and the cavities are closed structures. The positive electrode material that includes the stress relief particles can be used to effectively tackle a stress and relieve the stress in advance, relieve a strain of the positive electrode material used at a high voltage, avoid ruptures of particles of the positive electrode material, and enhance structural stability of the positive electrode material. The positive electrode material and the electrochemical device having the positive electrode material achieve good high-voltage cycle performance and cycle stability.

Abstract: An electrochemical apparatus, including a positive electrode, a negative electrode, and an electrolyte. The negative electrode includes a negative electrode current collector and a negative electrode mixture layer formed on the negative electrode current collector, and the negative electrode mixture layer includes a negative electrode active substance. An elongation at a yield point of the negative electrode mixture layer and D50 of the negative electrode active substance satisfy a specified relationship, and the electrolyte includes a compound having a cyano group.

Abstract: A battery cell includes a first electrode plate, a second electrode plate, and an insulating adhesive. The first electrode plate includes a first current collector, a first coating, and a first active layer, the first coating is disposed between the first current collector and the first active layer and includes a thermal expansion material. The first electrode plate and the second electrode plate are wound at intervals, the first electrode plate is the outermost electrode plate of the battery cell and further includes a first end which is a winding ending end, a surface of the first current collector at the first end facing toward the center of the battery cell is provided with the first active layer. The insulating adhesive includes a first sub-insulating adhesive disposed on a surface of the first current collector on the outermost side of the battery cell facing away from the first active layer.

Abstract: A negative electrode includes a current collector and an active substance layer arranged on the current collector, and an ionic conductivity of the active substance layer is 0.01 S/m to 1 S/m. The ionic conductivity of the active substance layer is defined as 0.01 S/m to 1 S/m, so that the electrochemical device can meet requirements for fast charging, and meanwhile, lithium plating on a surface of the negative electrode of the electrochemical device can be inhibited in a fast-charging condition, ensuring safety performance of the electrochemical device.

Abstract: An electrochemical device includes a separator, the separator includes: a porous substrate; a first coating layer including a material that reversibly intercalates and de-intercalates of lithium; and a second coating layer including one or both of inorganic particles and a polymer, wherein the first coating layer is arranged between the porous substrate and the second coating layer, the material that reversibly intercalates and de-intercalates of lithium comprises at least one of artificial graphite, natural graphite, mesocarbon microbeads, soft carbon, hard carbon, titanium-niobium oxide, and lithium titanate, wherein the electrochemical device is wound-type. According to the application, the first coating layer is arranged on one or both surfaces of the porous substrate, and therefore the safety performance, rate performance, and cycle performance of the electrochemical device are improved.

Abstract: The present application relates to a composite separator, and an electrochemical device and an electronic device comprising the same. Some embodiments of the present application provide a composite separator, comprising: a first porous substrate and a cation exchange layer, wherein the cation exchange layer comprises a second porous substrate grafted with a functional group, wherein the functional group is selected from the group consisting of an alkali-metal-sulfonic functional group, an alkali-metal-phosphoric functional group and a combination thereof. The composite separator of the present application can effectively capture the transition metal ions eluted from a cathode through the cation exchange layer, thereby reducing the deposition of the transition metal ions on an anode and the self-discharge rate of the electrochemical device.

Abstract: An electrode assembly formed by winding a first electrode plate, a separator and a second electrode plate. The first electrode plate comprises a first current collector and a first active material layer arranged on a surface of the first current collector. A winding terminating end of the first electrode plate is positioned on an outer side of a winding terminating end of the second electrode plate facing away from a winding core. The first active material layer on the winding terminating end of the first electrode plate covers one surface of the first current collector facing toward the second electrode plate, The electrode assembly further comprises a first adhesive member arranged on an outer surface of the electrode assembly. The electrode assembly takes the winding terminating end of the first electrode plate as the tail end. The application further provides a battery having the same.

Abstract: A composite current collector includes a base body, a first connecting layer and a first conductive layer, the first connecting layer bonds the first conductive layer to a first surface of the base body; a first passivation layer is formed on one surface of the first conductive layer facing toward the first connecting layer. the first passivation layer may prevent an electrolyte from contacting the first conductive layer and causing the first conductive layer to be corroded and damaged when the electrolyte enters from one surface of the first connecting layer facing away from the first conductive layer, thereby improving the stability of the current collector; an electrode plate and an electrochemical device are provide.

Abstract: The present application relates to a composite separator, and an electrochemical device and an electronic device comprising the same. Some embodiments of the present application provide a composite separator, comprising: a first porous substrate and a cation exchange layer, wherein the cation exchange layer comprises a second porous substrate grafted with a functional group, wherein the functional group is selected from the group consisting of an alkali-metal-sulfonic functional group, an alkali-metal-phosphoric functional group and a combination thereof. The composite separator of the present application can effectively capture the transition metal ions eluted from a cathode through the cation exchange layer, thereby reducing the deposition of the transition metal ions on an anode and the self-discharge rate of the electrochemical device.

Abstract: Embodiments of the present application relate to an electrochemical device. Specifically, the electrochemical device includes a cathode, an anode and a separator, the separator being disposed between the cathode and the anode, the separator including a porous substrate and a porous layer, and the porous layer being disposed on a surface of the porous substrate and including inorganic particles and a binder, where a ratio of a puncture elongation of the porous substrate to a puncture force of the porous substrate is about 1.5 mm/N to about 25 mm/N. A lithium-ion battery including the separator, provided by the present application, improves the safety performance of the lithium-ion battery.

Abstract: An electrolyte includes a compound of formula 1: R1 and R2 are each independently selected from H, halogen atom, a substituted or unsubstituted C1-10 alkyl group, a substituted or unsubstituted C3-10 cycloalkyl group, a substituted or unsubstituted C2-10 alkenyl group, a substituted or unsubstituted C2-10 alkynyl group, a substituted or unsubstituted C1-10 alkoxy group, a substituted or unsubstituted C6-10 aryl group, a substituted or unsubstituted C3-10 heteroaryl group, or any combination thereof. R is selected from a substituted or unsubstituted C1-10 alkyl group, a substituted or unsubstituted C3-10 cycloalkyl group, a substituted or unsubstituted C2-10 alkenyl group, a substituted or unsubstituted C2-10 alkynyl group, a substituted or unsubstituted C1-10 alkoxy group, a substituted or unsubstituted C6-10 aryl group or a substituted or unsubstituted C3-10 heteroaryl group, a substituted or unsubstituted C3-10 heterocycloalkyl group, a butyrolactam group, or any combination thereof.