An electrolytic solution contains: an electrolyte including a lithium salt represented by general formula (1) below; an organic solvent including a linear carbonate represented by general formula (2) below; and an unsaturated cyclic carbonate, wherein the linear carbonate is contained at a mole ratio of 3 to 6 relative to the lithium salt, and/or the lithium salt is contained at a concentration of 1.1 to 3.8 mol/L.
(R.sup.1X.sup.1)(R.sup.2SO.sub.2)NLi  general formula (1)
R.sup.20OCOOR.sup.21  general formula (2)

An electrolytic solution contains: an electrolyte including a lithium salt represented by general formula (1) below; an organic solvent including a linear carbonate represented by general formula (2) below; and an unsaturated cyclic carbonate, wherein the linear carbonate is contained at a mole ratio of 3 to 6 relative to the lithium salt, and/or the lithium salt is contained at a concentration of 1.1 to 3.8 mol/L.
(R.sup.1X.sup.1)(R.sup.2SO.sub.2)NLi  general formula (1)
R.sup.20OCOOR.sup.21  general formula (2)

There is provided a metal or metal-ion battery comprising an aluminum current collector and a low-corrosiveness non-aqueous electrolyte comprising, as a solvent, a carbonate compound of formula (I):

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This battery has an upper voltage limit of about 4.2 V or more and anodic dissolution of aluminum during battery operation at said voltage is suppressed.

An electrolyte solution contains tris(trimethylsilyl) phosphite and at least one fluorinated saturated cyclic carbonate (1) selected from pentafluoropropylethylene carbonate and heptafluoroisobutylethylene carbonate. Also disclosed is an electrochemical device including the electrolyte solution.

A bicyclic triolborate of the general formula

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and its use in an electrolyte composition. The use of a bicyclic triolborate in an electrolyte composition in electrochemical supercapacitors, such as for example in double-layer capacitors in electric motors.

A bicyclic triolborate of the general formula

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and its use in an electrolyte composition. The use of a bicyclic triolborate in an electrolyte composition in electrochemical supercapacitors, such as for example in double-layer capacitors in electric motors.

In some embodiments, an electrode can include a current collector, a composite material in electrical communication with the current collector, and at least one phase configured to adhere the composite material to the current collector. The current collector can include one or more layers of metal, and the composite material can include electrochemically active material. The at least one phase can include a compound of the metal and the electrochemically active material. In some embodiments, a composite material can include electrochemically active material. The composite material can also include at least one phase configured to bind electrochemically active particles of the electrochemically active material together. The at least one phase can include a compound of metal and the electrochemically active material.

Electrolytes and electrolyte additives for energy storage devices comprising an ether compound are disclosed. The energy storage device comprises a first electrode and a second electrode, wherein at least one of the first electrode and the second electrode is a Si-based electrode, a separator between the first electrode and the second electrode, an electrolyte, and at least one electrolyte additive selected from ether compounds.

Electrolytes and electrolyte additives for energy storage devices comprising an ether compound are disclosed. The energy storage device comprises a first electrode and a second electrode, wherein at least one of the first electrode and the second electrode is a Si-based electrode, a separator between the first electrode and the second electrode, an electrolyte, and at least one electrolyte additive selected from ether compounds.

The electrolyte additive includes a neutral compound represented by formula (1) and having, in the molecule, a trialkyl silyl group. It can improve the withstand voltage of the electrolyte and be applied to electrolyte for lithium-ion rechargeable batteries. In formula (1), R.sup.1 each represent independent C1-8 alkyl groups, R.sup.2 each represent independent C1-8 alkyl groups, A represents a C1-10 alkylene group, X represents either a single bond, a methylene group or one of the linking groups represented by formulas (2) to (4), m represents an integer from 1 to 3, n represents an integer from 0 to 2, where m+n is 2 if X is a single bond, a methylene group, a linking group represented by formula (2) or a linking group represented by formula (3), and m+n is 3 if X is a linking group represented by formula (4). In formula (3), R.sup.3 represents a C1-8 alkyl group.

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