Method of manufacturing non-aqueous electrolyte secondary battery
A method of manufacturing a non-aqueous electrolyte secondary battery includes: (A) constructing an electrode group including a positive electrode and a negative electrode; (B) impregnating the electrode group with a first electrolyte solution; (C) charging the electrode group impregnated with the first electrolyte solution to a voltage of 4.3 V or more; and (E) manufacturing the non-aqueous electrolyte secondary battery by impregnating the electrode group with a second electrolyte solution after the charging. The first electrolyte solution includes a first solvent, a first lithium salt, and biphenyl. The first solvent does not include 1,2-dimethoxyethane. The second electrolyte solution includes a second solvent and a second lithium salt. The second solvent includes 1,2-dimethoxyethane.
1. A method of manufacturing a non-aqueous electrolyte secondary battery, the method comprising:
constructing an electrode group including a positive electrode and a negative electrode;
impregnating the electrode group with a first electrolyte solution;
charging the electrode group impregnated with the first electrolyte solution to a voltage of 4.3 V or more; and
manufacturing the non-aqueous electrolyte secondary battery by impregnating the electrode group with a second electrolyte solution after the charging,
the first electrolyte solution including a first solvent, a first lithium salt, and biphenyl,
the first solvent not including 1,2-dimethoxyethane,
the second electrolyte solution including a second solvent and a second lithium salt,
the second solvent including 1,2-dimethoxyethane.
2. The method of manufacturing the non-aqueous electrolyte secondary battery according to claim 1 , wherein
the negative electrode includes composite particles,
the composite particles each include graphite and amorphous carbon,
the amorphous carbon covers a surface of the graphite, and
the first solvent includes ethylene carbonate.
3. The method of manufacturing the non-aqueous electrolyte secondary battery according to claim 1 , wherein the second solvent includes more than or equal to 10 volume % and less than or equal to 40 volume % of 1,2-dimethoxyethane.
4. The method of manufacturing the non-aqueous electrolyte secondary battery according to claim 1 , wherein the second solvent further includes more than or equal to 10 volume % and less than or equal to 30 volume % of ethylene carbonate, and more than or equal to 10 volume % and less than or equal to 30 volume % of ethyl methyl carbonate.
5. The method of manufacturing the non-aqueous electrolyte secondary battery according to claim 4 , wherein
the second solvent further includes more than or equal to 10 volume % and less than or equal to 30 volume % of dimethyl carbonate, and
in the second solvent, dimethyl carbonate has a volume ratio less than that of a sum of 1,2-dimethoxyethane and ethyl methyl carbonate.
6. The method of manufacturing the non-aqueous electrolyte secondary battery according to claim 1 , wherein the first electrolyte solution includes more than or equal to 1 mass % and less than or equal to 4 mass % of biphenyl.
7. The method of manufacturing the non-aqueous electrolyte secondary battery according to claim 1 , wherein the positive electrode includes a compound expressed by a formula (I):
LiNi a Co b Mn c O 2 (I)
where 0<a<1, 0<b<1, 0<c<1, and a+b+c=1.
8. The method of manufacturing the non-aqueous electrolyte secondary battery according to claim 1 , wherein the second solvent includes more than or equal to 20 volume % and less than or equal to 40 volume % of 1,2-dimethoxyethane.
9. The method of manufacturing the non-aqueous electrolyte secondary battery according to claim 1 , wherein the second solvent includes more than or equal to 30 volume % and less than or equal to 40 volume % of 1,2-dimethoxyethane.
10. The method of manufacturing the non-aqueous electrolyte secondary battery according to claim 1 , wherein the first electrolyte solution includes more than or equal to 2 mass % and less than or equal to 4 mass % of biphenyl.