Batteries made of lithium and seawater (or just plain tap water) could supply traction power to marine vehicles soon. , which impressed at the December IDTechEx Future of Electric Vehicles conference in San Jose has a grant from the Department of Energy's high risk, early-stage ARPA-E program. At the annual ARPA-E Summit one week ago, PolyPlus was highlighted as a potential game-changer by ARPA-E Director Arun Majumdar.
The company's water battery could get to market in two years time. Indeed, the company is starting to develop a water battery pilot production line now. An encapsulant encloses the lithium, completely separating it from the water, but still enabling a charge. A Japanese membrane is used in the three-layer system. This water battery can achieve a staggering 1,300 wh/kg for small batches, and potentially 1,500 wh/kg at larger scale production vs 200 wh/kg to 400 wh/kg for regular lithium-ion traction batteries. This is because this water battery also does not have to carry a positive electrode or the water, inside it. That also means the battery will be simpler and lower cost to produce.
PolyPlus thinks the addressable marine traction battery market could be half a billion dollars yearly. Compare that with IDTechEx estimating the civil marine traction battery market at $230 million, for example. PolyPlus is in the process of raising funds from VCs and strategic investors right now. When the funding round is closed, the water battery will be on its way. For more see the IDTechEx report Electric Vehicle Traction Batteries 2011 - 2021 .
For more attend Electric Vehicles - Land Sea Air Europe 2011
which has now been renamed from Future of Electric Vehicles to reflect its unique covering of the whole subject.
Image source: PolyPlus
