US 12,136,705 B2
Battery cell including surplus lithium disposed inside cavity of jelly roll for pre-lithiation, and method of forming the same
Jiang Fan, San Diego, CA (US); and Christopher Kompella, San Diego, CA (US)
Assigned to American Lithium Energy Corporation, Carlsbad, CA (US)
Filed by American Lithium Energy Corporation, Carlsbad, CA (US)
Filed on Oct. 17, 2019, as Appl. No. 16/656,277.
Claims priority of provisional application 62/747,027, filed on Oct. 17, 2018.
Prior Publication US 2020/0127336 A1, Apr. 23, 2020
Int. Cl. H01M 10/0587 (2010.01); H01M 4/04 (2006.01); H01M 4/38 (2006.01); H01M 10/0525 (2010.01); H01M 50/117 (2021.01); H01M 50/119 (2021.01); H01M 50/121 (2021.01); H01M 50/124 (2021.01)
CPC H01M 10/0587 (2013.01) [H01M 4/0459 (2013.01); H01M 4/382 (2013.01); H01M 10/0525 (2013.01); H01M 50/117 (2021.01); H01M 50/119 (2021.01); H01M 50/121 (2021.01); H01M 50/124 (2021.01)] 18 Claims
OG exemplary drawing
 
1. A battery cell protected for when the battery cell is discharged beyond a cutoff voltage of about 0 volts to 1.8 volts, comprising:
a jelly roll formed during an assembly of the battery cell by winding a separator, a positive electrode, and a negative electrode; and
over discharge protection comprising surplus lithium disposed inside a cavity formed at a center of the jelly roll by the winding the separator, the positive electrode, and the negative electrode, the surplus lithium being electrically decoupled from the positive electrode and the negative electrode during a formation of the battery cell which includes the assembly of the battery cell and subjecting the battery cell to an initial charging followed by at least a partial discharging of the battery cell, the surplus lithium being connected to the negative electrode but not the positive electrode once the battery cell is formed to compensate for lithium lost during the formation of the battery cell, the surplus lithium further remaining connected to the negative electrode but not the positive electrode in order for the surplus lithium to be discharged during a subsequent discharge of the battery cell to lithiate the battery cell and prevent an anodic corrosion of a negative current collector of the battery cell when the battery cell is over discharged.