The invention provides an electrolyte solution capable of providing an electrochemical device having low resistance and excellent high-temperature storage characteristics and cycle characteristics. The electrolyte solution contains lithium fluorosulfonate and a solvent containing a compound (1) represented by the following formula (1): CF.sub.2HCOOCH.sub.3.

The present disclosure provides a lithium-rich negative electrode plate, an electrode assembly and a lithium-ion battery, the lithium-rich negative electrode plate comprises a negative electrode collector and a negative electrode film, the negative electrode film is provided on a surface of the negative electrode collector and comprises a negative electrode active material, the lithium-rich negative electrode plate further comprises a layer of lithium metal provided on a surface of the negative electrode film. The negative electrode film further comprises a cyclic ester which is capable of forming a film on the negative electrode plate, a dielectric constant of the cyclic ester is larger than or equal to 10, and a reduction potential of the cyclic ester relative to Li/Li.sup.+ is lower than or equal to 1.5V.

An electrolyte solution containing a solvent and a compound represented by the following formula (1), wherein R.sup.1 is a C1-C5 linear or branched non-fluorinated alkyl group optionally containing an ether bond. Also disclosed is an electrochemical device including the electrolyte solution, a lithium ion secondary battery including the electrolyte solution and a module including the electrochemical device or lithium ion secondary battery. ##STR00001##

An electrolyte solution containing a solvent and a compound represented by the following formula (1), wherein R.sup.1 is a C1-C5 linear or branched non-fluorinated alkyl group optionally containing an ether bond. Also disclosed is an electrochemical device including the electrolyte solution, a lithium ion secondary battery including the electrolyte solution and a module including the electrochemical device or lithium ion secondary battery. ##STR00001##

An electrolyte including a dinitrile compound, a trinitrile compound, and propyl propionate. Based on the total weight of the electrolyte, the weight percentage of the dinitrile compound is X, the weight percentage of the trinitrile compound is Y, and the weight percentage of the propyl propionate is Z, wherein, about 2.2 wt %≤(X+Y)≤about 8 wt %, about 0.1≤(X/Y)≤about 2.3, about 5 wt %≤Z≤about 50 wt %, 1 wt %<Y<5 wt %, and about 0.02≤(Y/Z)≤about 0.3; wherein wherein the dinitrile compound is one or more compounds selected from the group consisting of butanedinitrile, adiponitrile, and 1,4-dicyano-2-butene; and the trinitrile compound is one or more compounds selected from the group consisting of 1,3,6-hexanetricarbonitrile, 1,2,6-hexanetricarbonitrile and 1,2,3-tris(2-cyanoethoxy)propane.

An electrolyte solution containing: a compound (1) represented by the following formula (1):

##STR00001##

wherein R.sup.101 to R.sup.103 are each independently a C1-C5 organic group optionally containing at least one selected from the group consisting of a hetero atom and an unsaturated bond, and R.sup.101 to R.sup.103 form no ring.

An electrolytic solution comprising N-(fluorosulfonyl)-N-(fluoroalkylsulfonyl)imide or di(fluorosulfonyl)imide, from which a residual solvent that affects the properties of the electrolyte solution material is reduced, is provided. A method for producing an electrolyte solution material containing fluorosulfonyl imide salt represented by the following general formula (1) and an electrolyte solution preparation solvent comprises decompressing and/or heating a solution containing the fluorosulfonyl imide salt and the electrolyte solution preparation solvent to volatilize a production solvent for the fluorosulfonyl imide salt. ##STR00001##
In general formula (1), R.sub.1 represents a fluorine atom or a fluorinated alkyl group having 1 to 6 carbon atoms, R.sub.2 represents an alkali metal ion.

An electrolytic solution comprising N-(fluorosulfonyl)-N-(fluoroalkylsulfonyl)imide or di(fluorosulfonyl)imide, from which a residual solvent that affects the properties of the electrolyte solution material is reduced, is provided. A method for producing an electrolyte solution material containing fluorosulfonyl imide salt represented by the following general formula (1) and an electrolyte solution preparation solvent comprises decompressing and/or heating a solution containing the fluorosulfonyl imide salt and the electrolyte solution preparation solvent to volatilize a production solvent for the fluorosulfonyl imide salt. ##STR00001##
In general formula (1), R.sub.1 represents a fluorine atom or a fluorinated alkyl group having 1 to 6 carbon atoms, R.sub.2 represents an alkali metal ion.

A supercondenser includes at least two electrodes separated by at least one separator having a polyhydroxyalkanoate (PHA) and at least one electrolyte, and relative production process. The supercondenser is flexible, biodegradable, and biocompatible, and can be made with reduced manufacturing costs and can be integrated, for example, in electronic devices that must be used inside biological organisms.

The present disclosure relates to the synthesis and evaluation of difluorophosphate additives for use in energy storage devices. The difluorophosphate additive may be selected from the group consisting of lithium difluorophosphate (LFO), sodium difluorophosphate (NaFO), ammonium difluorophosphate (AFO), tetramethylammonium difluorophosphate (MAFO), potassium difluorophosphate (KFO), and combinations thereof. In some instances, the difluorophosphate additive is not lithium difluorophosphate (LFO).