Sounds like the next sci-fi blockbuster to hit the multiplexes but in fact it’s a relatively new type of battery that is promising to become a key part of our renewable energy infrastructure.
The problem with all renewables is that the sun is often only a little sunny and the wind is often only mildly windy. As a result overcapacity is required. But what happens when the sun is bright or the wind is very…windy? At present renewables make up such a small percentage of our energy mix this simply isn’t a problem. However, in the future when perhaps as much as 80% or more of our energy is renewable we will need a cost effective and reliable method to store excess energy for later use.
Several schemes have been proposed from pumping compressed CO2 into disused mine shafts or even powering hydrogen generators but these may only be suitable for certain locations.
Enter the vanadium redox battery. These have actually been around for 20 years but had limited use because of limitations in their ability to work outside quite narrow temperature ranges. These batteries are very different to conventional types and work by pumping charged electrolyte chemicals through a reactor cell.
The advantage of a redox battery over other types are many but the key ones are:
1. Storage capacity limited only by tank size.
2. Long lasting chemicals that can be refreshed rather than discarding the entire battery
3. No charge memory and lasts indefinitely
Fast forward to 2011 and new research has yielded redox batteries that offer 70% more capacity and work between -5 and +50 degrees Celsius. As we make the switch to a low carbon economy technologies such as vanadium redox are going to play a major role.