Aqueous flow batteries(AFBs) are among the most promising electrochemical energy storage solutions for the massive-scale adoption of renewable electricity because of decoupled energy and power, design flexibility, imp...Aqueous flow batteries(AFBs) are among the most promising electrochemical energy storage solutions for the massive-scale adoption of renewable electricity because of decoupled energy and power, design flexibility, improved safety and low cost. The development of high-voltage AFB is, however, limited by the lack of stable anolytes that have low redox potential. Here we report Eu-based anolytes for high-voltage p H-neutral AFB applications. Eu^(3+) has a reduction potential of -0.39 V vs. SHE, which can be dramatically lowered when forming stable complex with inexpensive organic chelates. A typical complex, Eu DTPA,features a low redox potential of -1.09 V vs. SHE, fast redox kinetics, and a high water solubility of 1.5 M. When paired with ferrocyanide, the battery had an open-circuit voltage of 1.56 V and demonstrated stable cell cycling performance, including a capacity retention rate of 99.997% per cycle over500 cycles at 40 m A cm^(-2), a current efficiency of >99.9%, and an energy efficiency of >83.3%. A high concentration anolyte at 1.5 M exhibited a volumetric capacity of 40.2 Ah L^(-1), which is one of the highest known for p H-neutral AFBs, promising a potent solution for the grid-scale storage of renewable electricity.展开更多
Redox mediators(RMs),serving as intermediate electron carriers or reservoirs,play vital roles in developing new charge transfer energy storage systems with high voltage or capacity in aqueous batteries.However,the und...Redox mediators(RMs),serving as intermediate electron carriers or reservoirs,play vital roles in developing new charge transfer energy storage systems with high voltage or capacity in aqueous batteries.However,the underlying mechanism and selection criteria of RMs remain unclear in aqueous batteries,which hinders the further exploitation of new RMs and aqueous battery chemistries.展开更多
基金project has been supported by the National Natural Science Foundation of China (Nos. 21878281, 21922510 and 21720102003)the DNL Cooperation Fund, CAS (DNL201910)。
文摘Aqueous flow batteries(AFBs) are among the most promising electrochemical energy storage solutions for the massive-scale adoption of renewable electricity because of decoupled energy and power, design flexibility, improved safety and low cost. The development of high-voltage AFB is, however, limited by the lack of stable anolytes that have low redox potential. Here we report Eu-based anolytes for high-voltage p H-neutral AFB applications. Eu^(3+) has a reduction potential of -0.39 V vs. SHE, which can be dramatically lowered when forming stable complex with inexpensive organic chelates. A typical complex, Eu DTPA,features a low redox potential of -1.09 V vs. SHE, fast redox kinetics, and a high water solubility of 1.5 M. When paired with ferrocyanide, the battery had an open-circuit voltage of 1.56 V and demonstrated stable cell cycling performance, including a capacity retention rate of 99.997% per cycle over500 cycles at 40 m A cm^(-2), a current efficiency of >99.9%, and an energy efficiency of >83.3%. A high concentration anolyte at 1.5 M exhibited a volumetric capacity of 40.2 Ah L^(-1), which is one of the highest known for p H-neutral AFBs, promising a potent solution for the grid-scale storage of renewable electricity.
基金supported by the National Key R&D Program of China(grant nos.2018YFA0209401 and 2018YFE0201701)National Natural Science Foundation of China(NSFC grant no.22109029)+1 种基金Natural Science Foundation of Shanghai(grant no.22ZR1403600)Fudan University(grant nos.JIH2203010 and IDH2203008/003).
文摘Redox mediators(RMs),serving as intermediate electron carriers or reservoirs,play vital roles in developing new charge transfer energy storage systems with high voltage or capacity in aqueous batteries.However,the underlying mechanism and selection criteria of RMs remain unclear in aqueous batteries,which hinders the further exploitation of new RMs and aqueous battery chemistries.