VoltStorage raised 24 mn USD from Cummins engines.                

Renewable energy has not taken over since it’s very tough to store anywhere.

There are numerous ways to store renewable energy.

The scales of Lithium Ion battery production makes them easier to obtain than other batteries but they are still challenges including supply chain challenges.

There is a lot of competition for cell materials and thus there are companies who want to make batteries out of more cheaply and easily available materials like Iron.

Voltstorage CTO said that they don’t want to be dependent on certain supply chains.

Their first product was a vanadium redox flow battery suited to industrial users that stores enough energy to last a few hours, enough for some users. However, as the company was exploring scaling up, the US and China trade war started and COVId 19 messed up their supply chains. A lot of battery materials became very expensive for some time, and now in this case, it was some time where the prices were very expensive. 

That’s when the company chanced on iron-ion batteries..Iron has a massive global supply chain, it’s a good alternative to more expensive metals like lithium, cobalt and vanadium.

VoltStorage recently raised a Series C worth $24 million from engine manufacturer Cummins. Its previous rounds had SOSV and EIT InnoEnergy.

ESS Inc makes Iron-ion-flow batteries. And Form Energy also makes iron-air batteries. 

The iron-redox reactions are less efficient than Lithium Ion batteries. These modules fit inside 20 feet long shipping containers which can also be installed in buildings.

The cost of the battery along with wind and solar power combined needs to be below 70 USD per MWh. That’s more than running existing natural gas power plants, but the price of fossil fuels is unstable. There is a certainty of costs for grid-scale storage which is willing to be borne.