Abstract: A negative electrode material includes a silicon-based material, where for a test cell including an electrode containing the negative electrode material and a counter electrode made of lithium metal, first-cycle efficiency of the test cell is 81% to 86%, and a discharge capacity at an electric potential of the electrode in the test cell being 0.17V accounts for 35% to 65% of a first-cycle discharge capacity of the test cell. A lithiation platform of particles of a silicon-based material is so defined that a lithiation capacity when an electric potential of the silicon-based negative electrode material in a test half cell is 0.17V accounts for 35% to 65% of a first-cycle lithiation capacity of the test half cell, thereby ensuring amorphous characteristics of the silicon-based material, significantly improving cycling performance of the negative electrode material, and reducing a swelling rate of an electrode assembly during cycling.

Abstract: A negative electrode material includes silicon-based particles and graphite particles. In a case that a Dn50/Dv50 ratio of the graphite particles is A and a Dn50/Dv50 ratio of the silicon-based particles is B, the following conditional expressions (1) to (3) are satisfied: 0.1?A?0.65 (1); 0.3?B?0.85 (2); and B>A (3), where, Dv50 is a particle diameter of particles measured when a cumulative volume fraction in a volume-based distribution reaches 50%, and Dn50 is a particle diameter of particles measured when a cumulative number fraction in a number-based distribution reaches 50%. The present invention further provides a negative electrode plate, a lithium-ion secondary battery or electrochemical device containing the negative electrode plate, and an electronic device containing the lithium-ion secondary battery and/or electrochemical device.

Abstract: An assembly includes: an electrolytic solution, where the electrolytic solution includes a solvent and an additive, the additive includes fluoroethylene carbonate, and a weight percent of the fluoroethylene carbonate in a total mass of the solvent and the additive is 10% to 30%; and a negative electrode, where the negative electrode contains an active material and a protection layer that covers the active material. The protection layer is located between the electrolytic solution and the active material, the protection layer is in contact with the electrolytic solution, the active material contains lithium metal, and the protection layer contains silicon. The electrode assembly greatly improve the cycle performance of a lithium metal battery.

Abstract: An anode active material, and an electrochemical device and electronic device using such anode active material. Also, an anode active material, including graphite. Controlling a graphitization degree of particles of different particle sizes of the anode active material can achieve a balance between kinetic performance and first cycle efficiency of the electrochemical device.

Abstract: An anode material having 0.8?0.06×(Dv50)2?2.5×Dv50+Dv99?12 (1); and 1.2?0.2×Dv50?0.006×(Dv50)2+BET?5 (2), where Dv50 represents a value in the volume-based particle size distribution of the anode material that is greater than the particle size of 50% of the particles, Dv99 represents a value in the volume-based particle size distribution of the anode material that is greater than the particle size of 99% of the particles, and BET is a specific surface area of the anode material, wherein Dv50 and Dv99 are expressed in ?m and BET is expressed in m2/g. The anode material is capable of significantly improving the rate performance of electrochemical devices.

Abstract: A negative electrode plate includes a current collector and an active layer. The active layer includes a porous carbon framework and includes silicon nanoparticles and lithium metal that are located in the porous carbon framework. Embodiments of this application reduce the volume change of the negative electrode plate during cycles, suppress growth of lithium dendrites, improve safety of the lithium-ion battery, and achieve a higher energy density of the battery that contains the negative electrode plate.

Abstract: A negative electrode plate includes a negative current collector, a lithium metal negative electrode, and a negative electrode framework. A polarization electric field exists inside the negative electrode framework. A direction of the polarization electric field is directed from a surface of the negative electrode to the negative current collector. A material of the negative electrode framework includes at least one of a piezoelectric polymer, piezoelectric ceramic, or piezoelectric monocrystal. The negative electrode plate can control lithium deposition sites, effectively suppress the growth of lithium dendrites, effectively mitigate volume expansion of the electrochemical device, and further improve cycle performance of the electrochemical device.

Abstract: A negative electrode plate includes a three-dimensional framework structure. The three-dimensional framework structure includes fibers and rigid particles. Mohs hardness of the rigid particles is greater than or equal to 2, and an elastic modulus of the rigid particles is greater than or equal to 40 Gpa. The three-dimensional framework structure can mitigate volume expansion of the negative active material during cycling. On the other hand, the rigid particles help to stabilize the three-dimensional framework structure and can serve as a lithium wetting material to induce lithium to deposit inside the three-dimensional framework, thereby reducing the generation of lithium dendrites and improving safety performance and cycle performance of the formed electrochemical device.

Abstract: An electrochemical device includes a negative electrode. The negative electrode includes a current collector layer, a lithium metal layer, and a porous framework layer that are arranged in sequence. The porous framework layer is partly intercalated in the lithium metal layer. A thickness by which the porous framework layer is intercalated in the lithium metal layer is 0.2 ?m to 50 ?m. The electrochemical device achieves excellent cycle performance and relatively high safety and reliability.

Abstract: A negative electrode plate includes a negative current collector and a piezoelectric layer. A polarization electric field exists on the piezoelectric layer. A direction of the polarization electric field is directed from the negative current collector to a surface of a negative electrode. A material of the piezoelectric layer includes at least one of a piezoelectric polymer, piezoelectric ceramic, piezoelectric monocrystal, or an inorganic piezoelectric material. The negative electrode plate can control lithium deposition sites, effectively suppress the growth of lithium dendrites, and significantly improve the cycle performance and safety performance of the lithium metal battery.

Abstract: A magnetic current collector includes a permanent magnet material layer. In the permanent magnet material layer, remanence intensity of a permanent magnet material is 0 T to 2 T. The magnetic current collector can introduce a magnetic field into the lithium metal battery. The magnetic field interacts electromagnetically with an electric field exerted by the battery to quicken a mass transfer process of lithium ions at an interface between a negative electrode and an electrolytic solution, homogenize a current density generated by a lithium-ion flow on a surface of the negative electrode, quicken a mass transfer process of lithium ions in a direction parallel to the current collector, and homogenize the distribution of lithium ions, so as to suppress lithium dendrites and improve the cycle performance of the lithium metal battery.

Abstract: An anode material includes silicon-based particles and graphite particles, wherein the average sphericity degree of the graphite particles is A, the average sphericity degree of the silicon-based particles is B, and A and B meet: 0<B?A?0.3. The anode material has good cycle performance, and the battery prepared with the anode material has better rate performance and lower deformation rate.

Abstract: A negative electrode material, including an oxygen-containing silicon material. In a Raman spectrum of the oxygen-containing silicon material, IA represents a peak intensity at a corresponding peak position of 140 cm?1±10 cm?1 in the Raman spectrum, ID represents a peak intensity at a corresponding peak position of 470 cm?1±10 cm?1 in the Raman spectrum, and IE represents a peak intensity at a corresponding peak position of 510 cm?1±10 cm?1 in the Raman spectrum; and 0<IA/ID<2, and 0?IE/IA<5. In this way, after the electrochemical device containing the negative electrode material is cycled, all crystalline silicon is converted into non-crystalline silicon, thereby decreasing the volume change of the negative electrode material in the electrochemical device and improving the cycle performance and expansion performance of the electrochemical device.

Abstract: A negative electrode includes a negative current collector, a first negative active material layer and a second negative active material layer. The first negative active material layer is arranged on one side of a first portion of the negative current collector, and the second negative active material layers are arranged on two sides of a second portion, different from the first portion, of the negative current collector. A ratio of a weight per unit area of the first negative active material layer to a weight per unit area of the second negative active material layer on the negative current collector is 0.47 to 0.52, and a ratio of a compacted density of the first negative active material layer to a compacted density of the second negative active material layer is 0.9 to 1.1.

Abstract: A negative electrode active material having a median particle size D1v50, the negative electrode active material has a median particle size D2v50 under a pressure of 1 t, and D2v50/D1v50 is not less than 0.8. The negative electrode active material achieves a balance between high capacity and high cycle expansion performance of an electrochemical device.

Abstract: An electronic device, a charging method for an electrochemical device, a terminal and a storage medium. The electronic device includes an electrochemical device that satisfies the following features: in a first stage of a charging process, a state of charge (SOC) of the electrochemical device being less than or equal to X, 70%?X<100%. An average charging current when the SOC of the electrochemical device is less than or equal to 40% is A, an average charging current when the SOC of the electrochemical device is between 40% and X is B, and A<B. The electronic device can improve the cycle life of the corresponding electrochemical device with a charging time close to that of the current fast charging.

Abstract: A negative electrode includes a negative current collector and a negative active material layer. The negative active material layer includes a silicon-based material. A weight ratio R of the silicon-based material to a total weight of the negative active material layer and an absolute strength ? of the negative current collector satisfy the following formula: K=?/(1.4×R+0.1), where K is a relation coefficient, and the relation coefficient is greater than or equal to 4,000 N/m. The electrochemical device can effectively mitigate XY expansion and deformation of the negative active material layer by using the foregoing negative electrode, thereby enhancing cycle performance and safety performance of the electrochemical device.

Abstract: A negative electrode includes a current collector and a coating located on the current collector. The coating includes silicon-based particles and graphite particles. The silicon-based particles include a silicon-containing substrate and a polymer layer. The polymer layer includes a polymer and carbon nanotubes. The polymer layer is located on at least a part of a surface of the silicon-containing substrate. A minimum value of film resistances at different positions on a surface of the coating is R1, a maximum value of the film resistances is R2, an R1/R2 ratio is M, and a percentage of a weight of the silicon-based particles in a total weight of the silicon-based particles and the graphite particles is N, where M?0.5, and N is 2 wt %-80 wt %.

Abstract: A protective material for a negative electrode of a lithium metal battery in this application includes a first protective layer and a second protective layer that are adjacent to each other. The first protective layer is contiguous to a lithium metal. Also, a method for manufacturing the protective material for a negative electrode of a lithium metal battery, and a method for manufacturing the negative electrode.

Abstract: A negative electrode material includes a silicon-containing material. The silicon-containing material includes at least one of pure silicon, silicon carbon, a silicon alloy, or a silicon oxide. A ratio B/A of a maximum value B in differentials dQ/dV with respect to 0.4V-0.55V to a maximum value A in differentials dQ/dV with respect to 0.2V-0.35V is 1.0-3.0 when the negative electrode material is electrified in a delithiation direction in a case of charging and discharging a battery that includes the negative electrode material used as a working electrode, metallic lithium used as a counter electrode, and an electrolyte containing a lithium-ion conductive substance, and in a case of plotting a relationship curve between a differential dQ/dV and a working electrode potential V, where the differential is obtained by differentiating a charge/discharge capacity Q with respect to the working electrode potential V.