(JP10162858-A)      A non-aqueous electrolyte secondary cell comprises pair(s) of electrodes, and a separator provided between the paired electrodes and impregnated with a non-aqueous electrolyte containing a mixed solvent of propylene carbonate and ethylene carbonate.    The electrode(s) has, at least on surfaces, an active substance layer made of composite carbon particles, which individually comprise a core of crystalline carbon and a low crystallinity or amorphous carbon layer formed on at least a part of the surfaces of the core, and a carbon matrix covering at least a part of the composite carbon particles and uniformly dispersing and holding the composite carbon particles therein.    USE -   Used as batteries for portable electric appliances and electric cars.    ADVANTAGE -   This non-aqueous secondary cell has a high capacity and a high efficiency along with a flat discharge potential and good low temperature characteristics. When used under low temperature conditions, the mixed solvent can be free of any rise in viscosity and can be prevented from the formation of any precipitate.    (US6027833-A)      A non-aqueous electrolyte secondary cell comprises pair(s) of electrodes, and a separator provided between the paired electrodes and impregnated with a non-aqueous electrolyte containing a mixed solvent of propylene carbonate and ethylene carbonate.    The electrode(s) has, at least on surfaces, an active substance layer made of composite carbon particles, which individually comprise a core of crystalline carbon and a low crystallinity or amorphous carbon layer formed on at least a part of the surfaces of the core, and a carbon matrix covering at least a part of the composite carbon particles and uniformly dispersing and holding the composite carbon particles therein.    USE -   Used as batteries for portable electric appliances and electric cars.    ADVANTAGE -   This non-aqueous secondary cell has a high capacity and a high efficiency along with a flat discharge potential and good low temperature characteristics. When used under low temperature conditions, the mixed solvent can be free of any rise in viscosity and can be prevented from the formation of any precipitate.