POLYMER SOLID ELECTROLYTE LITHIUM SECONDARY BATTERY

摘要

PURPOSE:To provide a polymer solid electrolyte lithium secondary battery whose life can be expanded by suppressing the dendrite formation. CONSTITUTION:As an electrolyte 5, methoxyoligoethyleneoxypolyphosphazene is used. As a supporting salt, LiBF4 at 2-15wt.% of the methoxyoligoethyleneoxypolyphosphazene is used. Since lithium ion is solvated selectively with BF4<-> and precipitated on a negative electrode active material 4 in the methoxyoligoethyleneoxypolyphosphazene at the time of charging of a battery, lithium is precipitated almost uniformly in the whole surface of the negative electrode active material and thus dendrite formation can be suppressed.