Flow batteries are mainly produced with low-cost materials and without ‘conflict’ materials such as cobalt.
Vanadium, the most commonly used electrolytes in flow batteries, is widely available. As well as through mining, vanadium can be recovered from waste products such as mining slag, oil field sludge and fly ash. When a vanadium flow battery is decommissioned, the vanadium electrolyte can be recovered and reused by up to 97%, leading to lower environmental impacts and a lower cost of ownership.
Flow battery technologies can also be based on organic electrolytes that avoid the use of metals completely. Sodium chloride, one of the main raw materials in organic flow batteries, is highly available in the European market. Indeed, the EU is the second largest producer of sodium chloride globally. Even at 50GW of output, only a single-digit percentage of the annual salt mining in Germany is required for organic flow batteries. This results in substantial independence from global supply chains and scalability of applications in Europe.
Developing a local flow battery chain would lower the environmental impact of energy storage by reducing the emissions related to the transport of raw materials. As flow batteries have a longer operational time, the embodied energy amortised over the technology’s lifetime is lower than competing technologies.
Indeed, flow batteries have a very long operational life that can exceed 20 000 cycles and 20 years. During this period, flow batteries can cycle and recharge with almost no loss in power. A longer operational time likewise means less energy is needed to construct and maintain flow batteries across their entire lifecycle.
Finally, flow batteries are modular meaning that individual parts can be replaced or reused if necessary.