Abstract: An electrochemical apparatus includes a positive electrode, a negative electrode, a separator, and an electrolyte. The electrolyte includes a diluent, an electrolytic salt, and a compound of formula III. The diluent is selected from a group consisting of a compound of formula I and a compound of formula II. A molar mass of the diluent is Mz, and based on a total weight of the electrolyte, a percentage of the diluent is z wt %; a molar mass of the electrolytic salt is Mx, and based on the total weight of the electrolyte, a percentage of the electrolytic salt is x wt %; and a molar mass of the compound of formula III is My, and based on the total weight of the electrolyte, a percentage of the compound of formula III is y wt %, satisfying: 0.4 : 1 ? y M ? y : x M ? x ? 4 : 1 ; and z M ? z y M ? y + x M ? x ? 1.5 .

Abstract: An electrolyte includes fluoroethylene carbonate, where a percentage a of the fluoroethylene carbonate is 0.01% to 5% based on mass of the electrolyte; the positive electrode includes a positive electrode active material, where the positive electrode active material contains element Mn, and a percentage of the element Mn is greater than or equal to 15% based on mass of the positive electrode active material; and the positive electrode active material has a unit reaction area c measured in m2/cm2, where a and c satisfy the following relationship: 0.0006?a/c?6.25, and the unit reaction area is a product of a weight W of the positive electrode active material per unit area and a specific surface area BET of the positive electrode active material.

Abstract: An electrochemical apparatus includes a positive electrode and an electrolyte. The electrolyte includes ethylene carbonate (EC), propylene carbonate (PC), and succinonitrile (SN). The positive electrode includes a positive electrode active material, where the positive electrode active material includes metal element A, and the metal element A includes at least one of the following elements: Mg, Zr, or Al. Based on a mass of the electrolyte, a mass percentage of SN is a %, a mass percentage of EC is b %, and a mass percentage of PC is c %, where k=b/c, 1.25?k?6, and a/k?0.2. Based on a mass of the positive electrode active material, a mass percentage of the metal element A is x %, where 0.01?x?1. The foregoing electrochemical apparatus exhibits excellent high-temperature cycling performance and high-temperature interval cycling performance.

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: An electrolytic solution includes a compound containing a —CN functional group and a compound containing a silicon functional group. M is C or Si. R11, R12, and R13 are each independently selected from a substituted or non-substituted C1-C12 alkylene group, a substituted or non-substituted C2-C12 alkenylene group, an O—R group, an R0—S—R group or an R0—O—R group, R0 and R are each independently selected from a substituted or non-substituted C1-C6 alkylene group. n is 0 or 1. R14 is H, fluorine, a cyano group, a substituted or non-substituted C1-C12 alkyl group, a substituted or non-substituted C2-C12 alkenyl group, an O—R1 group, an R0—S—R1 group, or an R0—O—R1 group. R0 is a substituted or non-substituted C1-C6 alkylene group, and R1 is a substituted or non-substituted C1-C6 alkyl group.

Abstract: An electrochemical apparatus, including a positive electrode, a negative electrode, an separator, and an electrolyte, wherein the positive electrode comprises a current collector and a positive active material layer, and the positive active material layer comprises a positive active material; and the electrolyte comprises a compound of Formula I: wherein R11, R12, R13, R14, R15 and R16 are each independently selected from: H, halogen, and the following substituted or unsubstituted groups: a C1-8 alkyl group, a C2-8 alkenyl group, a C2-8 alkynyl group, or a C6-12 aryl group; and an amount of the compound of Formula I required per 1 g of the positive active material is about 0.001 g to about 0.064 g. The present application can effectively improve high-temperature storage and high-temperature cycle performance of an electrochemical apparatus.

Abstract: The present application relates to an electrolyte and an electrochemical device including the same. The electrolyte includes a diboronic acid compound and a nitrile compound, so that the storage performance and cycle performance of the electrochemical device using the electrolyte can be remarkably improved.

Abstract: An electrochemical device includes a negative electrode and an electrolyte solution. The negative electrode includes a negative current collector and a negative electrode mixture layer. The negative electrode mixture layer includes a first section, a second section, and a third section arranged sequentially in a thickness direction. The first section, the second section, and the third section are of an identical thickness. A ratio of a porosity P1 of the first section to a porosity P2 of the third section is P. The electrolyte solution includes an additive A, which is at least one selected from a compound of Formula I or a compound of Formula II: Based on a total mass of the electrolyte solution, a mass percent of the additive A is w %, satisfying 1?w?60, P=P1/P2, and P/(w %+1)?50%.

Abstract: An electrolyte including an imidazolium salt compound and a pyridine compound. The electrolyte, includes a compound of Formula I and a compound of Formula II: where R1 is selected from halo, cyano, substituted or unsubstituted C1-C12 alkyl, substituted or unsubstituted C2-C12 alkenyl, substituted or unsubstituted C2-C12 alkynyl, substituted or unsubstituted C2-C12 alkoxy, substituted or unsubstituted C3-C12 cycloalkyl, and substituted or unsubstituted C6-C12 aryl; and R11, R12, R13, R14 and R15 are each independently selected from H, halo, cyano, substituted or unsubstituted C1-C12 alkyl, substituted or unsubstituted C2-C12 alkenyl, substituted or unsubstituted C2-C12 alkynyl, substituted or unsubstituted C2-C12 alkoxy, substituted or unsubstituted C3-C12 cycloalkyl, and substituted or unsubstituted C6-C12 aryl; when substituted, the substituent is halo or cyano.

Abstract: An electrochemical apparatus includes a positive electrode, a negative electrode, a separator, and an electrolyte, where the positive electrode includes a positive electrode current collector, a positive electrode active substance layer, and a conductive coating disposed between the positive electrode current collector and the positive electrode active substance layer; the electrolyte includes a first fluorine-containing metal salt, where the first fluorine-containing metal salt includes at least one of fluorine-containing sulfonimide lithium salts; and the electrochemical apparatus satisfies the following relationship: 0.1?X/d?105, where X g/m2 is mass per unit area of fluorine-containing sulfonimide lithium salt contained in the electrochemical apparatus on one surface of the positive electrode current collector, and d ?m is thickness of the conductive coating on one surface of the positive electrode current collector.

Abstract: An electrolyte includes ethyl propionate, propyl propionate, ethylene carbonate, and propylene carbonate, where based on a total mass of the electrolyte, a mass percentage of ethyl propionate is a %, a mass percentage of propyl propionate is b %, a mass percentage of ethylene carbonate is c %, and a mass percentage of propylene carbonate is d %, where 20?a+b?50, 0<c/d<1, and 15?c+d?50. The electrolyte significantly improves floating charge performance of electrochemical apparatuses at high voltage.

Abstract: An electrochemical device includes a negative electrode and an electrolytic solution. The negative electrode includes a negative current collector and a negative active material layer disposed on at least one surface of the negative current collector. The negative active material layer includes a first region and a second region. A thickness of any position of the first region is less than an average thickness of the second region. The electrolytic solution includes a salt containing a P—O bond, and the salt accounts for a given content. The electrochemical device according to this application achieves excellent cycle performance.

Abstract: An electrochemical device, including a positive electrode, a negative electrode, a separator, and an electrolytic solution. The negative electrode includes a negative active material layer. The negative active material layer includes a silicon material. The electrolytic solution includes fluorocarbonate and cyclic ether. A weight percent of the fluorocarbonate, a weight percent of the cyclic ether, and a unit reaction area of the negative active material layer satisfy a specific relational expression, thereby improving the high-temperature storage performance and the high-temperature cycle performance of the electrochemical device.

Abstract: An electrolyte including an imidazolium salt compound and a pyridine compound. The electrolyte, includes a compound of Formula I and a compound of Formula II: where R1 is selected from halo, cyano, substituted or unsubstituted C1-C12 alkyl, substituted or unsubstituted C2-C12 alkenyl, substituted or unsubstituted C2-C12 alkynyl, substituted or unsubstituted C2-C12 alkoxy, substituted or unsubstituted C3-C12 cycloalkyl, and substituted or unsubstituted C6-C12 aryl; and R11, R12, R13, R14 and R15 are each independently selected from H, halo, cyano, substituted or unsubstituted C1-C12 alkyl, substituted or unsubstituted C2-C12 alkenyl, substituted or unsubstituted C2-C12 alkynyl, substituted or unsubstituted C2-C12 alkoxy, substituted or unsubstituted C3-C12 cycloalkyl, and substituted or unsubstituted C6-C12 aryl; when substituted, the substituent is halo or cyano.

Abstract: The present application relates to an electrolytic solution and an electrochemical device comprising the electrolytic solution. The electrolytic solution comprises a carbonate compound having a silicon-containing functional group, so as to significantly improve the overcharge performance and high-temperature storage performance of an electrochemical device using the electrolytic solution.

Abstract: An electrochemical apparatus, including a positive electrode, a negative electrode, an separator, and an electrolyte, wherein the positive electrode comprises a current collector and a positive active material layer, and the positive active material layer comprises a positive active material; and the electrolyte comprises a compound of Formula I: wherein R11, R12, R13, R14, R15 and R16 are each independently selected from: H, halogen, and the following substituted or unsubstituted groups: a C1-8 alkyl group, a C2-8 alkenyl group, a C2-8 alkynyl group, or a C6-12 aryl group; and an amount of the compound of Formula I required per 1 g of the positive active material is about 0.001 g to about 0.064 g. The present application can effectively improve high-temperature storage and high-temperature cycle performance of an electrochemical apparatus.

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: An electrolytic solution includes a compound containing a —CN functional group and a compound containing a silicon functional group. M is C or Si. R11, R12, and R13 are each independently selected from a substituted or non-substituted C1-C12 alkylene group, a substituted or non-substituted C2-C12 alkenylene group, an O—R group, an R0—S—R group or an R0—O—R group, R0 and R are each independently selected from a substituted or non-substituted C1-C6 alkylene group. n is 0 or 1. R14 is H, fluorine, a cyano group, a substituted or non-substituted C1-C12 alkyl group, a substituted or non-substituted C2-C12 alkenyl group, an O—R1 group, an R0—S—R1 group, or an R0—O—R1 group. R0 is a substituted or non-substituted C1-C6 alkylene group, and R1 is a substituted or non-substituted C1-C6 alkyl group.

Abstract: An electrolyte including a bis-cyclic sulfite compound and a multi-nitrile compound, which can form a stable protective layer on a positive electrode surface to ensure a lithium-ion battery stably operates at a voltage of ?4.45V. The electrolyte can remarkably improve a high temperature intermittent cycle capacity retention ratio and a high temperature resistant safety performance upon circulation of the high-voltage lithium-ion battery.

Abstract: The present application relates to a gel polymer electrolyte and an electrochemical device comprising the gel polymer electrolyte. The gel polymer electrolyte according to the present application comprises a polymer film and an organic electrolytic solution comprising a lithium salt, a phosphate ester compound, and a fluoroether compound. The gel polymer electrolyte according to the present application has higher ionic conductivity and better electrochemical stability, and is capable of significantly improving the safety and cycle performance of the electrochemical device.