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: A negative active material includes composite particles. The composite particle includes a first region and a second region, where the first region includes a disordered carbon structure, and the second region includes an ordered carbon structure and/or a metal oxide structure. The negative active material of this application has a high gram capacity and active ion diffusion coefficient, so that a secondary battery containing such negative active material has a high energy density and excellent cycling performance, rate performance, and fast charging capacity.

Abstract: An electrode assembly includes a first electrode plate, a separator, and a second electrode plate that are disposed in a stack. The first electrode plate and the second electrode plate respectively have coating areas and empty foil areas arranged at intervals. Centers of the coating areas overlap each other to form a coating portion of the electrode assembly, and centers of the empty foil areas overlap each other to form a flexible portion of the electrode assembly. The first packaging layer coats the coating portion and the flexible portion of the electrode assembly, and the second packaging layer at least coats the first packaging layer on the flexible portion.

Abstract: An electrochemical device includes a positive electrode, the positive electrode includes a positive electrode active material layer, the positive electrode active material layer includes a positive electrode active material and a composite carbon material. A is a volume of the positive electrode active material layer, B is a volume of pores having a pore diameter of less than 2 ?m in the positive electrode active material layer, and 14%?B/A?20%. The positive electrode active material layer includes the positive electrode active material and the composite carbon material, and 14%?B/A?20%, and indicates that the formed positive electrode has abundant pores for lithium ion transport.

Abstract: Provided are a coating apparatus and a coating system, where the coating apparatus includes: a coating module, the coating module including a coating roller and a coating die, where the coating roller is configured to drive, when rotating, a substrate to move toward the coating die, and the coating die is configured to apply a coating onto the substrate; an error acquisition module having a predetermined distance to the coating roller and configured to acquire a circular run-out error of rotation of the coating roller and transmit the circular run-out error to a linkage module; and the linkage module configured to adjust position of the coating die in real time according to the circular run-out error transmitted to the linkage module, so as to keep a distance between the coating roller and the coating die unchanged.

Abstract: An electrochemical device includes a housing, an insulator, a connecting strip and a feedthrough connector. The housing defines an accommodation cavity and includes a cover having a second surface. The cover includes a first through-hole. A second through-hole of the connecting strip communicates with the first through-hole. The insulator is fitly connected to the connecting strip. The insulator includes a third through-hole communicating with the second through-hole. A first part of the feedthrough connector is fitly connected to a surface of the insulator being away from the connecting strip. The first part covers the third through-hole. One end of a second part of the feedthrough connector is connected to a surface of the first part oriented toward the connecting strip. The second part extends away from the first part and is partly disposed in the first through-hole, the second through-hole, and the third through-hole.

Abstract: This application relates to the field of batteries, and in particular, to an electrode assembly and a manufacturing method therefor, a battery cell, a battery, and an electric apparatus. The electrode assembly may include: a first electrode plate, being folded back and forth in a first direction so that the first electrode plate includes a plurality of first laminates connected and stacked in sequence; and a second electrode plate, being opposite the first electrode plate in polarity and being folded once in a second direction so that the second electrode plate includes two second laminates connected to each other, where the second direction may be perpendicular or parallel to the first direction, and the second laminates and the first laminates may be alternately stacked in sequence.

Abstract: A negative electrode plate includes: a negative current collector; a first negative active material layer close to the negative current collector and disposed on at least one surface of the negative current collector, where the first negative active material layer includes a first negative active material; and a second negative active material layer. The second negative active material layer includes a second negative active material. The first negative active material layer is located between the second negative active material layer and the negative current collector. An interlayer spacing of the first negative active material is smaller than an interlayer spacing of the second negative active material.

Abstract: A method for improving cycling performance of a battery includes, in a first stage, charging the battery with a first-stage current until a voltage of the battery reaches a first-stage voltage value and in a second stage, charging the battery with a second-stage current until the voltage of the battery reaches a second-stage voltage value. The second-stage voltage value is greater than the first-stage voltage value, and the second-stage current is less than the first-stage current.

Abstract: An electrochemical device includes a positive electrode, the positive electrode includes a current collector and a film layer containing a positive active material. The film layer is disposed on at least one surface of the current collector. The positive active material includes a primary particle and/or a secondary particle. When a mass percent A of the primary particle in the positive active material based on a mass of the positive active material satisfies 20%?A?100%, the film layer, the positive active material, and the current collector satisfy: Dl?Dv99?Dc; and, when a mass percent A? of the primary particle in the positive active material based on the mass of the positive active material satisfies 0?A??20%, the film layer, the positive active material, and the current collector satisfy: Dl?1.1 Dv99.

Abstract: An electrochemical device including a housing, an electrode assembly, and a first bonding piece. The electrode assembly is located in the housing. The first bonding piece bonds the housing and the electrode assembly together. A bonding strength between the first bonding piece and the housing is F1, and a bonding strength between the first bonding piece and the electrode assembly is F2, 5%?F1/F2?70%, and 15 N/m?F1?500 N/m.

Abstract: A cell includes an electrode assembly. The electrode assembly includes: a first electrode plate including a first current collector, a first active substance layer provided on a surface of the first current collector, and a first uncoated foil area without the first active substance layer; a second electrode plate; and a separator disposed between the first electrode plate and the second electrode plate. The electrode assembly is formed by winding the first electrode plate, the separator, and the second electrode plate in sequence. In a winding direction of the electrode assembly, each layer from the second layer to the second outermost layer of the first electrode plate includes a first flat section, and a first bent section and a second bent section provided on two sides of the first flat section respectively.

Abstract: An electrochemical device includes a positive electrode and an electrolytic solution. The positive electrode includes a positive current collector and a positive active material layer disposed on at least one surface of the positive current collector. The positive active material layer includes a positive active material. The positive active material contains an Mg element. Based on a total weight of the positive active material, a weight of the Mg element is X ppm, and 300?X?30000. The electrolytic solution contains carboxylate. Based on a total weight of the electrolytic solution, a weight percent of the carboxylate is Y %, and Y?60. The electrochemical device satisfies 5?X/Y?6000. The electrochemical device effectively improve the high-temperature cycle performance and low-temperature discharge performance of the electrochemical device by controlling a relationship between the electrolytic solution and the positive active material.

Abstract: An electrochemical device, including a cathode, an anode and an electrolyte. The anode includes an anode current collector and an anode active material disposed on the anode current collector, the electrolyte includes fluoroethylene carbonate, and the electrochemical device meets the following relationship: 17.55?K1?K2?1.63K32+11.27K3?20.80, where K1 represents a specific surface area value of the unit mass of the anode active material (in m2/g), and 1.0?K1?2.0; K2 represents a content value of the fluoroethylene carbonate required by per Ah capacity (in g/Ah), and 0.05?K2?0.25; and K3 represents a weight value of the anode active material required by per Ah capacity (in g/Ah). The electrochemical device of the present application has improved kinetic performance and cycle performance.

Abstract: The present application provides a fire-fighting apparatus, a box assembly, a battery, a power consumption apparatus, and a method for preparing a battery. The fire-fighting apparatus includes: a pipe, a gas release mechanism, and a blocking structure. The pipe has an air inlet end and an air outlet end, and the air inlet end is configured to be connected to the battery, so that a combustible gas generated in the battery during thermal runaway events is capable of entering the pipe from the box via the air inlet end and being discharged from the pipe via the air outlet end; and the gas release mechanism is configured to be connected to the pipe and release a fire-fighting gas into the pipe when thermal runaway occurs in the battery; and the blocking structure is configured to block the combustible gas and the fire-fighting gas and change a flow direction.

Abstract: An electrolyte, including: a compound of Formula I, and at least one of a compound of Formula II or a compound of Formula III, R1, R2, R3 and R4 are each independently selected from hydrogen, fluoro, substituted or unsubstituted C1-C10 alkyl, substituted or unsubstituted C2-C10 alkenyl, substituted or unsubstituted C2-C10 alkynyl, substituted or unsubstituted C6-C12 aryl, substituted or unsubstituted C1-C10 alkoxy, or substituted or unsubstituted C6-C12 aryloxy, wherein when substituted, the substituent is fluoro, cyano or C1-C10 alkyl; and a, d and f are each independently selected from an integer from 1 to 5, and b, c, e, g, h and i are each independently selected from an integer from 0 to 5.

Abstract: A layered porous film includes a substrate film and a polymer coating provided on at least one side of the substrate film. The substrate film and the polymer coating satisfy both formula I and formula II: 0?(Tm1?Tm2)/M1?0.0005, formula I, and 0?(Tm1?Tm2)/M2?0.05, formula II; where Tm1 is a melting point of the substrate film, and M1 is a weight-average molecular weight of a polymer contained in the substrate film; and Tm2 is a melting point of the polymer coating, and M2 is a weight-average molecular weight of a polymer contained in the polymer coating. The layered porous film has advantages of low pore-closing temperature and high inflection resistance.

Abstract: The embodiments of the present application relate to an electrode sheet and a battery cell including the same. The electrode sheet according to an embodiment comprises an electrode sheet body and a plurality of tabs connected to the electrode sheet body. The width of each of the plurality of tabs is different from one another; or the length of each of the plurality of tabs is different from one another. The electrode sheet and the battery cell provided in the embodiments of the present application ensure that each of the tabs in the electrode sheet can electrically conduct well with the tab lead. Thus, the battery cell provided in the present application has the advantage of good electrical conductivity.

Abstract: An electrolyte includes an organic solvent, a lithium salt and additives, in particular, the additives include a fluoroethylene carbonate and a P—N bond-containing compound, the P—N bond-containing compound having a structure shown in formula I; A mass percentage of the fluoroethylene carbonate in the electrolyte is a %, a mass percentage of the P—N bond-containing compound in the electrolyte is b %, and 0.1?a/b?200.

Abstract: An electrochemical apparatus, including a package housing having a first package body and a second package body being integrally structured to form an accommodating portion and a sealing portion. A direction perpendicular to a surface of the sealing portion is a first direction. When viewed from the first direction, the accommodating portion includes a first edge extending a third direction and formed by the integral connection of the first package body and the second package body, and a second edge opposite to the first edge in a second direction. The sealing portion includes a third edge connected to the first edge. The first direction, the second direction, and the third direction are perpendicular to each other. In a second direction, a distance between the first edge and the second edge is d1, and a distance between the third edge and the second edge is d2, wherein d2?d1.