Gel electrolyte and gel electrolyte battery

1. A gel electrolyte comprising:

a matrix polymer;

a nonaqueous solvent; and

an electrolytic solution having an electrolyte salt containing lithium dissolved in the nonaqueous solvent, the matrix polymer being swollen with the electrolytic solution, wherein:

the matrix polymer comprises polyvinylidene fluoride copolymerized with at least hexafluoropropylene in an amount of 3 wt % or more and 7.5 wt % or less,

the nonaqueous solvent comprises ethylene carbonate; and at least one solvent selected from the group consisting of dimethyl carbonate, ethylmethyl carbonate, diethyl carbonate, ethylpropyl carbonate, ethyl butyl carbonate and dipropyl carbonate,

a content of the ethylene carbonate in the nonaqueous solvent is 15 wt % or more and 55 wt % or less, and

a total content of the at least one solvent in the nonaqueous solvent is 30 wt % or more and 85 wt % or less wherein the matrix polymer comprises the polyvinylidene fluoride further copolymerized with monochlorotrifluoroethylene in an amount of 3 wt % or more and 7.5 wt % or less.

2. The gel electrolyte of claim 1 , wherein the nonaqueous solvent comprises: ethylene carbonate; and at least two solvents selected from the group consisting of dimethyl carbonate, ethylmethyl carbonate, diethyl carbonate, ethylpropyl carbonate, ethyl butyl carbonate, and dipropyl carbonate.

3. A gel electrolyte battery comprising a positive electrode, a negative electrode, a separator, and a gel electrolyte, wherein:

the gel electrolyte comprises:

a matrix polymer;

a nonaqueous solvent; and

an electrolytic solution having an electrolyte salt comprising lithium dissolved in a nonaqueous solvent, the matrix polymer being swollen with the electrolytic solution, wherein:

the matrix polymer comprises polyvinylidene fluoride copolymerized with at least hexafluoropropylene in an amount of 3 wt % or more and 7.5 wt % or less,

the nonagueous solvent comprises: ethylene carbonate; and at least one solvent selected from the group consisting of dimethyl carbonate, ethylmethyl carbonate, diethyl carbonate, ethylpropyl carbonate, ethyl butyl carbonate, dipropyl carbonate,

a content of the ethylene carbonate in the nonaqueous solvent is 15 wt % or more and 55 wt % or less,

a total content of the at least one solvent in the nonagueous solvent is 30 wt % or more and 85 wt % or less wherein the matrix polymer comprises the polyvinylidene fluoride further copolymerized with monochlorotrifluoroethylene in an amount of 3 wt % or more and 7.5 wt % or less.

4. The gel electrolyte baffery according to claim 3 , wherein:

the negative electrode comprises at least one member selected from the group consisting of a carbon material, lithium metal, and a lithium alloy, and

the positive electrode comprises a lithium transition metal oxide capable of reversibly intercalating lithium.

5. The gel electrolyte battery according to claim 3 , wherein:

each of the positive electrode and the negative electrode has formed thereon an active material applied portion and a current collector exposed portion,

at the interface between the active material applied portion at the separator, the gel electrolyte covers a portion of the current collector exposed portion about 6 mm or less away from the boundary between the current collector exposed portion and the active material applied portion.

6. The gel electrolyte battery of claim 3 , wherein the nonaqueous solvent comprises: ethylene carbonate; and at least two solvents selected from the group consisting of dimethyl carbonate, ethylmethyl carbonate, diethyl carbonate, ethylpropyl carbonate, ethyl butyl carbonate, and dipropyl carbonate.