Polymer electrolyte secondary cell
View Patent ↗A polymer electrolyte secondary cell with high safety against overcharging includes a positive electrode containing a positive electrode active material; a negative electrode containing a negative electrode active material; a polymer electrolyte containing a non-aqueous solvent, an electrolyte salt, and a polymer. The non-aqueous solvent contains a tertiary carboxylic acid ester shown in Formula 1 below. The polymer is formed from monomers containing alkylene glycol (meth)acrylate and/or N,N-dialkyl (meth)acrylamide. where R1 to R4 each denote a straight-chained or branched alkyl group having 4 or less carbon atoms and may be the same or different.
1. A polymer electrolyte secondary cell comprising:
a positive electrode having a positive electrode active material;
a negative electrode having a negative electrode active material; and
a polymer electrolyte containing a non-aqueous solvent, an electrolyte salt, and a polymer, wherein
the non-aqueous solvent contains a tertiary carboxylic acid ester represented by Formula 1, and
the polymer is polymerized from monomers containing alkylene glycol (meth)acrylate and/or N,N-dialkyl (meth)acrylamide
where R1 to R4 each denote a straight-chained or branched alkyl group having 4 or less carbon atoms and may be the same or different.
2. The polymer electrolyte secondary cell according to claim 1 , wherein,
the tertiary carboxylic acid ester is methyl trimethylacetate and/or ethyl trimethylacetate.
3. The polymer electrolyte secondary cell according to claim 1 , wherein,
the alkylene glycol (meth)acrylate is polypropylene glycol diacrylate.
4. The polymer electrolyte secondary cell according to claim 3 , wherein,
the content of the polypropylene glycol diacrylate is 2.0 to 8.0 mass parts out of 100 mass parts of the total mass of the non-aqueous solvent and the electrolyte salt.
5. The polymer electrolyte secondary cell according to claim 1 , wherein,
the N,N-dialkyl (meth)acrylamide is N,N-dimethylacrylamide.
6. The polymer electrolyte secondary cell according to claim 5 , wherein,
the content of the N,N-dimethylacrylamide is 1.7 to 4.0 mass parts out of 100 mass parts of the total mass of the non-aqueous solvent and the electrolyte salt.
7. The polymer electrolyte secondary cell according to claim 1 , wherein
the content of the tertiary carboxylic acid ester in the total volume of the non-aqueous solvent is 10 to 90 volume % at 25° C. and 1 atm.