US 11,990,658 B2
Carbon dioxide-formate redox flow battery system
Jenny Y. Yang, Irvine, CA (US)
Assigned to THE REGENTS OF THE UNIVERSITY OF CALIFORNIA, Oakland, CA (US)
Filed by THE REGENTS OF THE UNIVERSITY OF CALIFORNIA, Oakland, CA (US)
Filed on Dec. 17, 2020, as Appl. No. 17/125,506.
Claims priority of provisional application 62/951,911, filed on Dec. 20, 2019.
Prior Publication US 2021/0194031 A1, Jun. 24, 2021
Int. Cl. H01M 8/18 (2006.01); H01M 4/92 (2006.01)
CPC H01M 8/188 (2013.01) [H01M 4/921 (2013.01); H01M 4/925 (2013.01)] 12 Claims
OG exemplary drawing
 
1. A redox flow battery, the system comprising:
a. a positive active material;
b. a negative active material comprising carbon dioxide, bicarbonate, or carbonate;
c. an electrocatalyst that converts the carbon dioxide, bicarbonate, or carbonate into formate to store electron equivalents to charge the battery, and oxidizes the formate to release the stored electrons and discharge the battery; and
d. an external acid in which the electrocatalyst performs the conversion, selected such that the electrocatalyst has a pKa equal to a pKa of the external acid, and wherein the electrocatalyst has a hydricity equal to a hydricity of formate under identical solvent conditions.