Battery cell including surplus lithium disposed inside cavity of jelly roll for pre-lithiation, and method of forming the same

Abstract

A battery cell may be formed to include a surplus lithium. The surplus lithium may be disposed inside a cavity formed by winding a separator, a positive electrode, and a negative electrode to form a jelly roll of the battery cell. The surplus lithium may be discharged in order to pre-lithiate the battery cell. For example, the surplus lithium may be coupled with the positive electrode and discharged while the battery cell is at least partially charged. Alternatively, the surplus lithium may be coupled with the negative electrode and discharged while the battery cell is at least partially discharged. Moreover, the surplus lithium may be coupled with a negative current collector of the battery cell in order to prevent one or more chemical reactions triggered by an over discharge of the battery cell from corroding the negative current collector of the battery cell.