Resin composition for gel polymer solid electrolyte, composition for gel polymer solid electrolyte, and gel polymer solid electrolyte, composite electrode, and electrochemical device using the same
(57) [Summary] [PROBLEMS] To apply various electrochemical devices, To provide a gel polymer solid electrolyte having excellent ionic conductivity and mechanical strength. SOLUTION: The gel polymer solid electrolyte of the present invention comprises: (A) a polyether copolymer containing an ethylene oxide-modified glycidyl ether compound and ethylene oxide as main components, and (B) a compound having three or more ethylenically unsaturated bonds in a molecule or a melamine compound having an ethylenically unsaturated bond And (C) an electrolyte solution.