Review—Bipolar Plates for the Vanadium Redox Flow Battery

Bipolar plates are one of the key components of vanadium redox flow batteries. They electrically conduct and physically separate adjacent cells in series and provide structural support to the stack. Bipolar plates are exposed to harsh conditions due to the acidic vanadium electrolyte and high potential differences which occur in vanadium redox flow batteries. Therefore, the material needs to fulfil good electrical conductivity, sufficient impermeability and mechanical stability as well as long-term chemical and electrochemical resistivity. This review provides a comprehensive overview of carbon-polymer based composites which are preferentially applied for bipolar plates in the vanadium redox flow battery. It addresses the composite materials, their production, properties, degradation mechanisms, designs and costs. In addition, it covers challenges and potentials for further development and optimization.