POLYMER ELECTROLYTE

In a polymer electrolyte having a structure in which an organic electrolyte is held in an organic polymer, the polymer electrolyte has following structures (i) through (iii). (i) A skeleton of the organic polymer has a crosslink structure. (ii) The organic polymer has a microporous structure. (iii) The organic electrolyte is held by swelling in the skeleton of organic polymer, and also held in micropores. According to this polymer electrolyte, a high ionic conductivity can be obtained and a stable structure can be kept for a long period.