| abstract |
An objective of the present invention is to provide a gel polymer electrolyte composition which exhibits excellent electrolyte retaining ability, excellent ion conductivity, higher mechanical strength and excellent shape preservation, which does not require an extra step for crosslinking, and which can provide a secondary battery with excellent cycle properties and a vinyl acetal polymer used for a gel polymer electrolyte composition. There are provided a vinyl acetal polymer for a gel polymer electrolyte composition, wherein the vinyl acetal polymer has a cationic functional group, as well as a gel polymer electrolyte composition comprising the vinyl acetal polymer and an electrolyte solution, wherein a weight ratio of the vinyl acetal polymer to the electrolyte solution is 0.5:99.5 to 9:91. |