Method for Producing Non-Aqueous Electrolyte Secondary Battery

摘要

A method for producing a non-aqueous electrolyte secondary battery including an electrolyte containing an electrolyte salt, a non-aqueous solvent capable of dissolving the electrolyte salt, and plural additives, wherein at least one of the additives has a reduction potential that is nobler than the reduction potential of the non-aqueous solvent. The method includes a first charging step for maintaining battery voltage at a negative electrode potential at which the additive having the noblest reduction potential of the additives is decomposed while the non-aqueous solvent and other additives are not reduced and decomposed and a second charging step for maintaining battery voltage so as to have reduction and decomposition of at least one of the non-aqueous solvents and bring the electrical potential of the negative electrode to at least 0.7 V relative to lithium. By having a uniform reaction in an electrode, a decrease in durability is suppressed.

主权项

1. A method for producing a non-aqueous electrolyte secondary battery comprising a positive electrode, a negative electrode, and an electrolyte containing an electrolyte salt, a non-aqueous solvent capable of dissolving the electrolyte salt, and plural additives, wherein at least one of the additives has a reduction potential that is nobler than the reduction potential of the non-aqueous solvent, the method comprising:
an initial charging step including a first charging step for maintaining battery voltage at a negative electrode potential at which an additive having a noblest reduction potential of the additives is decomposed while the non-aqueous solvent and other additives are not reduced and decomposed, and a second charging step for maintaining battery voltage so as to have reduction and decomposition of at least one of the non-aqueous solvents and bring the electrical potential of the negative electrode to at least 0.7 V relative to lithium, wherein the additive having the noblest reduction potential is at least one selected from a group consisting of an oxalate compound represented by the following Formula (1): wherein M represents phosphorus or boron, n represents an integer from 0 to 4, and m represents an integer from 1 to 3, and when M is phosphorus, 2m+n=6, and when M is boron, 2m+n=4), and a disulfonic acid ester compound represented by the following Formula (2): wherein R1 represents a substituted or unsubstituted alkylene group with 1 to 3 carbon atoms, or a substituted or unsubstituted polyfluoroalkylene group with 1 to 3 carbon atoms, R2 and R3 each independently represent a substituted or unsubstituted alkyl group with 1 to 4 carbon atoms, or a substituted or unsubstituted polyfluoroalkyl group with 1 to 4 carbon atoms, and R2 and R3 may bind with each other to form a ring, and in the case of forming a ring, R3 may be a single bond, at least one additive which is included other than the additive having the noblest reduction potential has a potential that is nobler than that of the non-aqueous solvent having the noblest reduction potential to be reduced and decomposed in the second charging step, and at least one of the additives that are additionally contained forms an SEI film during the second charging step.