Conducting polymer electrodes for high power Vanadium Redox Flow Batteries

The storage of electricity is the bottleneck to mass implement renewable energy sources.

The fluctuation of power generated by intermittent solar and wind power plants must be balanced by energy storage devices that react in various time scales and that are geographically located in various locations. In that context, battery solutions become an important piece of the puzzle on the energy map.

Today, two major battery technologies are being investigated for large scale stationary electrical storage applications: Li-ion batteries and Vanadium redox flow batteries (VRFBs).

Several studies reveal that VRFBs have a clear first pole position compared to Li-ion batteries on sustainability issues from life cycle analysis.

One clear advantage is that the vanadium electrolyte after running many cycles (>30 000) in the battery can be restored at 97% efficiency, which give many lives for the energy storage material (liquid electrolyte) battery compared to the second life considered today for the electrodes in Li-ion batteries.

Now, the only remaining drawback of VRFBs is the low power per area of electrode delivered.

Hence, any attempts to increase the power in VRFB, such as improving the electron transfer rate at the electrode-electrolyte interface will bring this technology one step further to market penetration and the mass-implementation of renewable energy solutions needed for an urgent energy transition. Here we use a novel strategy with conducting polymer electrodes.