Researchers obtain promising results against capacity loss in vanadium batteries

An article by researchers at the Center for Development of Functional Materials (CDMF) in Brazil describes a successful strategy to mitigate charge capacity loss in vanadium redox flow batteries, which are used by electric power utilities among other industries and can accumulate large amounts of energy. The article is published in the Chemical Engineering Journal.

CDMF is a Research, Innovation and Dissemination Center (RIDC) funded by FAPESP and hosted by the Federal University of São Carlos (UFSCar) in São Paulo state.

The study involved computer simulations designed to find out how ion leakage between the anolyte and catholyte, called transport loss, leads to battery deactivation, and how to mitigate this loss so as to keep ion concentration constant over time. Initially, the researchers estimated the effects of current density, active species concentration and volumetric flow on capacity loss. The second stage sought optimal conditions to minimize capacity loss based on the flow between electrolyte tanks in the opposite direction to cross-contamination (transport of electroactive species through the membrane). 

The results showed current density and active species concentration to be the main variables affecting capacity loss. According to the researchers, their approach successfully mitigated cross-contamination in different combinations of the two variables, providing an optimal flow between electrolyte tanks under different operating conditions.

Ernesto Pereira, last author of the article and a professor at UFSCar, noted that the main advantage of redox flow batteries is lack of electrode aging as the electroactive components are dissolved in solutions instead of being coated onto electrodes.

Commercial vanadium redox flow batteries are expected to have a longer lifetime than other types, although the study was conducted on a small scale. “Energy efficiency loss due to aging is minimal, given the slow pace of aging,” he said. 

The researchers explained that they are exploring and analyzing flow batteries computationally, with commercial batteries as a model, as part of a broader strategy that includes the development of novel organic substances for this type of battery.

About São Paulo Research Foundation (FAPESP)

The São Paulo Research Foundation (FAPESP) is a public institution with the mission of supporting scientific research in all fields of knowledge by awarding scholarships, fellowships and grants to investigators linked with higher education and research institutions in the State of São Paulo, Brazil. FAPESP is aware that the very best research can only be done by working with the best researchers internationally. Therefore, it has established partnerships with funding agencies, higher education, private companies, and research organizations in other countries known for the quality of their research and has been encouraging scientists funded by its grants to further develop their international collaboration. You can learn more about FAPESP at www.fapesp.br/en and visit FAPESP news agency at www.agencia.fapesp.br/en to keep updated with the latest scientific breakthroughs FAPESP helps achieve through its many programs, awards and research centers. You may also subscribe to FAPESP news agency at http://agencia.fapesp.br/subscribe.