US 12,087,983 B2
Carbon dioxide redox flow battery having a bi-functional negative electrode
Pooya Hosseini-Benhangi, Vancouver (CA); Christina Gyenge, Vancouver (CA); and Elod Gyenge, Vancouver (CA)
Assigned to AGORA ENERGY TECHNOLOGIES LTD., Vancouver (CA)
Filed by Agora Energy Technologies Ltd., Vancouver (CA)
Filed on Jun. 15, 2021, as Appl. No. 17/348,544.
Claims priority of provisional application 63/041,612, filed on Jun. 19, 2020.
Prior Publication US 2021/0399328 A1, Dec. 23, 2021
Int. Cl. H01M 8/00 (2016.01); H01M 8/18 (2006.01); H01M 8/22 (2006.01); H01M 4/02 (2006.01)
CPC H01M 8/188 (2013.01) [H01M 8/22 (2013.01); H01M 2004/027 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A redox flow battery comprising:
(a) a negative electrode comprising a porous base layer, a bi-functional catalyst layer for electrochemical reduction of either CO2 or carbonate to formate during battery charging and for formate oxidation to either carbonate or CO2 during battery discharge, and a porous intermediate support layer situated between the porous base layer and the bi-functional catalyst layer and comprising a metal oxide and a carbon-based additive;
wherein the carbon-based additive comprises one or more of carbon black, graphene, or carbon nanotubes; and
wherein the metal oxide supports the bi-functional catalyst layer and comprises a non-platinum group material with no electrocatalytic activity toward formate oxidation reaction and poor electrocatalytic activity toward CO2 or carbonate reduction compared to PdSn, and further comprises:
a perovskite structure with the formula ABO3, wherein A is one or a mixture of La, Sr, and Ba and B is one of Co, Ti, Fe, Ni, Ga, Mg, In, Mn, Ta, or Ce; or
a fluorite structure with the formula ABO7, wherein A is Nd, and B is Ir;
(b) a positive electrode; and
(c) a cation exchange or bipolar membrane in between the negative and positive electrodes.