Polymer electrolyte and battery
View Patent ↗A polymer electrolyte capable of obtaining superior discharge characteristics and a battery using it are provided. A cathode ( 21 ) and an anode ( 22 ) are wound with a separator ( 24 ) in between. After that, the wound body is contained inside a package member. Then, an electrolytic composition containing a solvent, polyvinyl acetal or the derivative thereof, and lithium hexafluorophosphate is added thereto. Polyvinyl acetal or the derivative thereof is polymerized by using lithium hexafluorophosphate as a catalyst. Thereby, a polymer electrolyte ( 23 ) is formed, and the discharge characteristics are improved.
1. A polymer electrolyte comprising:
an electrolytic solution; and
a polymer compound having a structure in which at least one from the group consisting of polymerized polyvinyl acetal and polymerized polyvinyl acetal derivatives,
wherein,
the electrolytic solution comprises a solvent and lithium hexafluorophosphate, and a content of the polymer compound is within the range from 2 wt % to 5 wt %.
2. The polymer electrolyte according to claim 1 , wherein the content of the polymer compound is 3.5 wt % or less.
3. A battery comprising:
a cathode;
an anode;
a separator; and
a polymer electrolyte inside a package member,
wherein,
the polymer electrolyte comprises (1) an electrolytic solution containing a solvent and lithium hexafluorophosphate and (2) a polymer compound having a structure in which at least one from the group consisting of a polymerized polyvinyl acetal and polymerized polyvinyl acetal derivatives, and a content of the polymer compound in the polymer electrolyte is within the range from 2 wt % to 5 wt %, both inclusive.
4. The battery according to claim 3 , wherein the content of the polymer compound in the polymer electrolyte is 3.5 wt % or less.
5. The battery according to claim 3 , wherein the polymer compound is polymerized inside the package member.
6. The battery according to claim 3 , wherein the package member is made of a film-shaped material.
7. The battery according to claim 3 , wherein the separator includes a porous film containing at least one of polyethylene and polypropylene.