TY - JOUR
T1 - Enhanced cycle life of vanadium redox flow battery via a capacity and energy efficiency recovery method
AU - Wei, L.
AU - Fan, X. Z.
AU - Jiang, H. R.
AU - Liu, K.
AU - Wu, M. C.
AU - Zhao, T. S.
N1 - Funding Information:
The work described in this paper was fully supported by HKUST Fund of Nanhai (Grant No. FSNH-18FYTRI01), GICI Exploratory Project (Project No. GICI20EG02), and a grant from the Research Grants Council of the Hong Kong Special Administrative Region, China (Project No. T23-601/17-R).
Funding Information:
The work described in this paper was fully supported by HKUST Fund of Nanhai (Grant No. FSNH-18FYTRI01 ), GICI Exploratory Project (Project No. GICI20EG02 ), and a grant from the Research Grants Council of the Hong Kong Special Administrative Region, China (Project No. T23-601/17-R ).
Publisher Copyright:
© 2020 Elsevier B.V.
PY - 2020/12/1
Y1 - 2020/12/1
N2 - In this work, the cycle life of vanadium redox flow batteries (VRFBs) is extended by resolving the inevitable loss of capacity and energy efficiency after long-term cycle operation. The electrolyte concentration, volume, and valence are rebalanced by mixing the electrolyte as well as adding a quantitative amount of a reducing agent. Without disassembling the battery, the energy efficiency decay induced by electrode degradations is almost completely restored by interchanging the positive and negative electrodes. By adopting this method, the capacity and energy efficiency after 500 cycles can be restored to 473 mAh and 90.8%, almost reaching the previous highest level at the beginning of the cycle test (478 mAh and 91.0%). In addition, the rate performance tests also demonstrate that even at a current density of as high as 300 mA cm−2, the energy efficiency of the recovered battery is only 0.8% lower than the new battery. All the results show that the recovery method reported here allows the cycle life of VRFBs to be greatly prolonged with no need to replace electrolytes and electrodes.
AB - In this work, the cycle life of vanadium redox flow batteries (VRFBs) is extended by resolving the inevitable loss of capacity and energy efficiency after long-term cycle operation. The electrolyte concentration, volume, and valence are rebalanced by mixing the electrolyte as well as adding a quantitative amount of a reducing agent. Without disassembling the battery, the energy efficiency decay induced by electrode degradations is almost completely restored by interchanging the positive and negative electrodes. By adopting this method, the capacity and energy efficiency after 500 cycles can be restored to 473 mAh and 90.8%, almost reaching the previous highest level at the beginning of the cycle test (478 mAh and 91.0%). In addition, the rate performance tests also demonstrate that even at a current density of as high as 300 mA cm−2, the energy efficiency of the recovered battery is only 0.8% lower than the new battery. All the results show that the recovery method reported here allows the cycle life of VRFBs to be greatly prolonged with no need to replace electrolytes and electrodes.
KW - Capacity decay
KW - Energy efficiency loss
KW - Oxalic acid dihydrate
KW - Recovery method
KW - Vanadium redox flow battery
UR - http://www.scopus.com/inward/record.url?scp=85089804793&partnerID=8YFLogxK
U2 - 10.1016/j.jpowsour.2020.228725
DO - 10.1016/j.jpowsour.2020.228725
M3 - Journal article
AN - SCOPUS:85089804793
SN - 0378-7753
VL - 478
JO - Journal of Power Sources
JF - Journal of Power Sources
M1 - 228725
ER -
