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.

A member for a non-aqueous electrolyte battery containing a copolymer containing a tetrafluoroethylene unit and a fluoroalkyl vinyl ether unit, in which the number of functional groups per 10.sup.6 carbon atoms of a main chain of the copolymer is 100 or less, and a melt flow rate of the copolymer is 20 to 30 g/10 minutes.

A hybrid energy storage device has at least two half cells, wherein each half cell includes an electrode comprising an electrically conductive high surface area material incorporating an electrolyte comprising a dissolved species that can exist in more than two redox states, and at least one separator that separates the at least two half cells and allows transfer of selected charge carriers between the half cells. After an initial charging, a redox pair of one half cell is different from the redox pair of the other half cell. The hybrid energy storage device operates as a battery for low power applications, and as a supercapacitor for high power applications. The hybrid energy storage device may be flexible.

In an embodiment, an active material-based nanocomposite is synthesized by infiltrating an active material precursor into pores of a nanoporous carbon, metal or metal oxide material, and then annealing to decompose the active material precursor into a first gaseous material and an active material and/or another active material precursor infiltrated inside the pores. The nanocomposite is then exposed to a gaseous material or a liquid material to at least partially convert the active material and/or the second active material precursor into active material particles that are infiltrated inside the pores and/or to infiltrate a secondary material into the pores. The nanocomposite is again annealed to remove volatile residues, to enhance electrical contact within the active material-based nanocomposite composite and/or to enhance one or more structural properties of the nanocomposite. In a further embodiment, the pores may be further infiltrated with a filler material and/or may be at least partially sealed.

Electrolytes and electrolyte additives for energy storage devices comprising fluorinated cyclic compounds.

Electrolytes and electrolyte additives for energy storage devices comprising fluorinated cyclic compounds.

Disclosed are capacitors containing surface active ionic liquids, and methods of use. The capacitors have high capacitance and function over broad ranges of temperature, and are particularly appropriate for high-temperature (˜200° C.) applications.

Disclosed are capacitors containing surface active ionic liquids, and methods of use. The capacitors have high capacitance and function over broad ranges of temperature, and are particularly appropriate for high-temperature (˜200° C.) applications.

A coolant includes a refrigerant, a porous plate-shaped heat insulator, and an enclosure in which the refrigerant and the heat insulator are enclosed in a sealed state, and the heat insulator has a thermal conductivity per unit area of 300 W/(K.Math.m.sup.2) or less and a thickness equal to or greater than 0.5 mm and equal to or less than 10.0 mm.

A coolant includes a refrigerant, a porous plate-shaped heat insulator, and an enclosure in which the refrigerant and the heat insulator are enclosed in a sealed state, and the heat insulator has a thermal conductivity per unit area of 300 W/(K.Math.m.sup.2) or less and a thickness equal to or greater than 0.5 mm and equal to or less than 10.0 mm.