The present technology is related to imide containing quaternary ammonium salts having a hydrocarbyl substituent of number average molecular weight less 300, and additive packages having such quaternary ammonium salts and improved stability.

A molten sodium-based battery comprises a robust, highly Na-ion conductive, zero-crossover separator and a fully inorganic, fully liquid, highly cyclable molten cathode that operates at low temperatures.

A molten sodium-based battery comprises a robust, highly Na-ion conductive, zero-crossover separator and a fully inorganic, fully liquid, highly cyclable molten cathode that operates at low temperatures.

Rechargeable electrochemical battery cells are disclosed. In particular, are disclosed discharge state assembled rechargeable electrochemical cells, which, when in discharged state, comprises an electrically conductive anodic current collector and a cathode that comprises metallic material as an active material.

Rechargeable electrochemical battery cells are disclosed. In particular, are disclosed discharge state assembled rechargeable electrochemical cells, which, when in discharged state, comprises an electrically conductive anodic current collector and a cathode that comprises metallic material as an active material.

Methods for producing ceramic films Yttria Stabilized Zirconia (3YSZ) and aluminum titanate (Al.sub.2TiO.sub.5), and the physical properties of these films are described. The films produced have thicknesses and integrity suitable for handling and corrosion resistance to electrolytes, porosity, ion permeability and electrical resistivity suitable for use as separators between positive and negative layers for forming electrical batteries, particularly lithium batteries.

An electrolyte includes an organic solvent and a cyclic ester compound that is substituted with a sulfonate group.

An electrolyte includes an organic solvent and a cyclic ester compound that is substituted with a sulfonate group.

The present disclosure provides a cathode active material comprising: lithium transition metal oxide-based particles; and a titanium dioxide coating layer formed on a part or a whole of a surface of the particle, in which the titanium dioxide coating layer is a partially reduced TiO.sub.2-x (0<x<2), a preparation method thereof, and a lithium secondary battery including the cathode active material. The cathode active material of the present disclosure may significantly improve electrochemical properties of an electrochemical device including the cathode active material, preferably a lithium secondary battery by decomposing lithium-containing impurities remaining on the surface of the cathode active material by a partially reduced titanium dioxide coating layer formed on the surface of the cathode active material and enhancing the electrical conductivity of the cathode active material.

An ultracapacitor that includes an energy storage cell immersed in an advanced electrolyte system and disposed within a hermetically sealed housing, the cell electrically coupled to a positive contact and a negative contact, wherein the ultracapacitor is configured to output electrical energy within a temperature range between about −40 degrees Celsius to about 210 degrees Celsius. Methods of fabrication and use are provided.