An electrolytic solution for an electrochemical device, including: a cation (C) that is a monovalent to trivalent metal ion; an anion (A); a solvent (SO) that is a compound having a molecular weight of 1,000 or less; and a polymer (P) that has a weight-average molecular weight of more than 10,000, wherein a content ratio of the solvent (SO) relative to 1 mol of the cation (C) is 0.5 to 4 mol, and a content ratio of the polymer (P) is 0.5% by weight or more. Also provided are a plastic composition, an electrode sheet, an insulating layer, and an electrochemical device including the electrolytic solution, as well as producing methods of these.

A technique that can improve ionic conductivity is provided.

An electrolyte includes an inorganic composite particle that is a composite of an inorganic particle with a compound having a betaine structure and one or more functional groups selected from a (meth)acryloxy group, a Si(OR).sub.3 group (R is a hydrogen atom or an alkyl group having 1 to 3 carbon atoms), and an Al(OR).sub.2 group (R is a hydrogen atom or an alkyl group having 1 to 3 carbon atoms).

An electrochemical device capable of more sufficiently preventing swelling due to generation of a gas such as carbon dioxide and decomposition of a lithium salt while having a simple structure. The electrochemical device includes a non-aqueous electrolytic solution, wherein the non-aqueous electrolytic solution contains a metal-organic framework containing: an azole-based organic molecule optionally having a hydrophobic group, and a metal atom.

An electrochemical device capable of more sufficiently preventing swelling due to generation of a gas such as carbon dioxide and decomposition of a lithium salt while having a simple structure. The electrochemical device includes a non-aqueous electrolytic solution, wherein the non-aqueous electrolytic solution contains a metal-organic framework containing: an azole-based organic molecule optionally having a hydrophobic group, and a metal atom.

Provided is a nonaqueous electrolyte solution for batteries, which contains an additive A that is composed of a boron compound represented by formula (1), and an additive B that has a lower reductive decomposition potential than the Additive A, in which n represents an integer from 1 to 5, M.sup.+ represents an Li.sup.+ ion or an H.sup.+ ion, and when n is an integer from 2 to 5, more than one M.sup.+ may be the same as or different from each other. ##STR00001##

Provided is a nonaqueous electrolyte solution for batteries, which contains an additive A that is composed of a boron compound represented by formula (1), and an additive B that has a lower reductive decomposition potential than the Additive A, in which n represents an integer from 1 to 5, M.sup.+ represents an Li.sup.+ ion or an H.sup.+ ion, and when n is an integer from 2 to 5, more than one M.sup.+ may be the same as or different from each other. ##STR00001##

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

##STR00001##

wherein R.sup.101 is a C2-C7 organic group and optionally includes at least one selected from the group consisting of a hetero atom and an unsaturated bond; and R.sup.102 is a C1-C3 organic group and optionally includes at least one selected from the group consisting of a hetero atom and an unsaturated bond.

Disclosed herein is a method for using a high temperature rechargeable energy storage device comprising (a) obtaining an HTRESD; and (b) at least one of (1) cycling the HTRESD by alternatively charging and discharging the HTRESD at least twice over a duration of 20 hours and (2) maintaining a voltage across the HTRESD for 20 hours, such that the HTRESD exhibits a peak power density between 0.005 W/liter and 75 kW/liter after 20 hours when operated at an ambient temperature in an operating temperature range comprising between about −40° C. and about 210° C.

Disclosed herein is a method for using a high temperature rechargeable energy storage device comprising (a) obtaining an HTRESD; and (b) at least one of (1) cycling the HTRESD by alternatively charging and discharging the HTRESD at least twice over a duration of 20 hours and (2) maintaining a voltage across the HTRESD for 20 hours, such that the HTRESD exhibits a peak power density between 0.005 W/liter and 75 kW/liter after 20 hours when operated at an ambient temperature in an operating temperature range comprising between about −40° C. and about 210° C.

There are provided: a nonaqueous electrolytic solution for an energy storage device provided with a positive electrode, a negative electrode, a separator and a nonaqueous electrolytic solution having an electrolyte salt dissolved in a nonaqueous solvent, wherein the potential of the positive electrode in a full-charge state is 4.5 V or higher on Li basis and the nonaqueous electrolytic solution contains at least one kind of tertiary carboxylic acid esters represented by the following general formula (I); and an energy storage device using the nonaqueous electrolytic solution.

##STR00001## wherein R.sup.1 to R.sup.3 each independently represent a methyl group or an ethyl group; and R.sup.4 represents a halogenated alkyl group having 1 to 5 carbon atoms.