Unicamp's flow battery in a lithium-dominated market

Brazil is starting to contract storage by auction, and the dominant chemistry is lithium. Researchers from the Faculty of Electrical Engineering at Unicamp presented a flow battery with two concentric cylindrical electrodes and internal electrolyte circulation, with no external pumps or hoses. The prototype uses lead dissolved in methanesulphonic acid, completed 400 charge and discharge cycles without additives and has a patent application at INPI, with support from Inova Unicamp.

The International Energy Agency report Batteries and Secure Energy Transitions, of 2024, records that LFP accounted for 80% of new stationary storage installed in 2023 and that the price of lithium batteries fell from USD 1,400 per kWh in 2010 to less than USD 140 per kWh in 2023.

Against that price, a new architecture does not compete on cell cost. It competes on operation and maintenance. An external pump is a rotating item, with seal, filter and scheduled shutdown throughout the asset's life. Removing the pump takes a recurring failure mode out of the O&M budget and simplifies container assembly.

Between 400 bench cycles and the service life that a grid contract requires lies a gap that only long-duration testing closes. It is that testing, and not the patent, that decides whether the research becomes an asset.