Several material-level developments are targeting the main cost and durability barriers in flow batteries, from vanadium electrolyte additives to non-fluorinated membranes and zinc-bromine corrosion control.

Vanadium electrolyte and temperature range

Yongtai Energy said at its 2026 semi-annual results briefing that its independently developed first-generation vanadium battery positive electrode solid capacity-enhancing material has completed multi-power system testing. The company is advancing trial production, pilot testing and mass production. Yongtai says the material significantly reduces the initial installation cost of vanadium battery electrolyte and can effectively broaden the system’s operating temperature range. It describes significant cost-reduction and efficiency-enhancement advantages and says the material has formed the core technical barrier of its energy storage business. Separately, Vnergy’s cooperation project with a key chemical group in Southwest China has entered the project initiation stage, with product certification underway with institutions such as Singapore’s A*STAR.

Membranes

Zhonghe Energy’s Porimion PBI membrane achieved 85% energy efficiency at 200 mA/cm2 in independent testing by a Japanese customer and showed no degradation during long-term charge/discharge at 600 mA/cm2 while suppressing vanadium ion crossover. In an overseas 3.8 kW stack test, the PBI membrane delivered 99.14% coulombic efficiency and 83.74% energy efficiency, with energy efficiency ranging from 79.24% to 84.55% across 83–166 mA/cm2 and 185 mW/cm2. The company also introduced SPEEK/SPPSU non-fluorinated membranes with acid-base swelling below 1%, positioned for multiple flow battery chemistries. A separate study found a 15 μm NC700 membrane with balanced electrolyte reduced capacity decay by 75.4% versus a conventional N117 system.

Zinc-bromine and electrode work

Chinese Academy of Sciences research published in Nature Energy reported solving zinc-bromine flow battery corrosion, achieving charge/discharge without corrosion, more than 700 cycles and energy density of 152 Wh/L. A three-year review of all-vanadium flow battery materials concluded that inorganic electrolyte additives offer the best cost-performance, membrane defluorination is key to efficiency and cost reduction, and electrodes need improved hydrophilicity and catalytic activity.

Membrane defluorination is described as a key route to improving efficiency and lowering cost in all-vanadium flow batteries.

These advances do not remove the need for full-system validation, but they show where the next round of cost reduction is coming from.

This article was assisted by AI analysis. Please refer to the original source for official information.