By Meghan Bialt-DeCelie

Image acquired from: https://en.wikipedia.org/wiki/Wind_power_in_New_Zealand

Figure 3: Windmills need reliable large-scale flow batteries to effectively store energy for later use.

The flow battery is a development in large-scale, renewable battery technology. It is often found attached to solar panels and windmills to collect the energy produced. However, it is unable to cost-effectively store large amounts of energy.

Dr. Qing Wang, of the University of Singapore, adapted the flow battery to use high-energy lithium ions, often used for laptop batteries, by using solid electrode materials as opposed to liquids. The team used a liquid redox mediator that transported charge from the solids through the apparatus. Finally, they modified the membrane, which separated the electrodes, with a polymer that allowed lithium ions to permeate.

This new lithium based battery was able to store 10 times more energy than the typical flow battery, however it traded off with an inadequately slower power delivery rate. If this can be improved, the lithium flow battery can keep renewable energy more consistent and reliable.

Sources:

1. Jia, et al. High-energy density nonaqueous all redox flow lithium battery enabled with a polymeric membrane. Science Advances. 1.10, e1500886 (2015).
2. R.F. Service, New type of ‘flow battery’ can store 10 times the energy of the next best device. Science News (2015).