A non-aqueous electrolyte is disclosed, which comprises a non-aqueous solvent
and
a solute represented by the general formula(1): MBR1R2R3R4,
wherein M is an alkali metal atom or an ammonium group and R1 to R4
are each independently electron withdrawing groups or electron withdrawing
atoms bound to B where at least one of R1 to R4 is other
than a fluorine atom. The solute has a thermal stability substantially equal to
that of LiBF4 and an anion portion having a high electronegativity,
and easily dissociates into ions. Therefore, a non-aqueous electrolyte containing
this solute has a high ionic conductivity and is difficult to cause a generation
of a gas or deterioration in characteristics due to the decomposition of the solute,
which occurs during use at high temperatures or after storage at high temperatures.
