Abstract: An electrolytic solution includes a solvent. The solvent includes a compound represented by Formula (1) below, in which R1 is a fluorinated C1 to C6 alkyl or a fluorinated C2 to C6 alkenyl, and R2 and R3 each independently are a hydrogen atom, a fluorine atom, or a fluorinated C1 to C6 alkyl. The solvent further includes ethylene carbonate. Based on a total weight of the solvent, a weight percent of the ethylene carbonate is less than or equal to 25 wt %.

Abstract: This application provides a positive electrode active material. Surface of a first lithium salt is coated with a coating layer containing a second lithium salt, which not only blocks the corrosive decomposition of the first lithium salt by the electrolyte but also allows the second lithium salt to form CEI films in situ on surfaces of the first lithium salt particles, thereby improving the film structure and avoiding the decomposition of active components in the electrolyte. Additionally, the second lithium salt contains both elements fluorine and phosphorus, which makes the composition of the film formed as consistent as possible with the composition of the film formed by lithium hexafluorophosphate in the electrolyte, thereby reducing the consumption of active lithium in the electrolyte. The positive electrode active material of this application can significantly improve the power performance and cycle life of batteries.

Abstract: Provided are a non-aqueous electrolyte and a preparation method thereof, and a secondary battery and an electric apparatus containing the same. The non-aqueous electrolyte contains a non-aqueous solvent and lithium ions, first cations, and first anions dissolved therein, where the first cation is a metal cation Men+ other than the lithium ion, n representing a chemical valence of the metal cation; the first anion is a difluoroxalate borate anion DFOB?; mass concentration of the first cations in the non-aqueous electrolyte is D1 ppm, and mass concentration of the first anions in the non-aqueous electrolyte is D2 ppm, both based on total mass of the non-aqueous electrolyte; and the non-aqueous electrolyte satisfies that D1 is 0.5 to 870 and that D1/D2 is 0.02 to 2. The non-aqueous electrolyte in this application enables the secondary battery to have good cycling performance, safety performance, and kinetic performance.

Abstract: A method of user identity verification by a server, where the server pre-configures, by use of collected user information, verification information corresponding to accounts of users in a user verification information data store, the verification information including a plurality of verification security challenges and a plurality of respective first verification answers. The method includes detecting a condition to whether initiate a user identity verification is satisfied, where an account ID of a user is obtained from the condition. The method also includes inquiring the pre-configured user verification information about verification information matching the account ID and transmitting security challenges of the inquired verification information to the client.

Abstract: A method of user identity verification by a server, where the server pre-configures, by use of collected user information, verification information corresponding to accounts of users in a user verification information data store, the verification information including a plurality of verification security challenges and a plurality of respective first verification answers. The method includes detecting a condition to whether initiate a user identity verification is satisfied, where an account ID of a user is obtained from the condition. The method also includes inquiring the pre-configured user verification information about verification information matching the account ID and transmitting security challenges of the inquired verification information to the client.