ReVolt plans for zinc-air battery to trump Li-ion with $13M in funding

Staefa, Switzerland-based ReVolt Technology said it has raised an additional €10 million ($13.1 million) toward its Series B funding, bringing the round to €15.5 million and total funding to €24 million.

The Swiss company developed rechargeable zinc-air batteries for military applications, mobile devices, consumer electronics and hearing aids.

The newest funding came from current investors NorthZone Ventures, SINTEF, Sofinnova Partners, TVM Capital, Verdane Capital and Viking Venture, as well as new investor RWE Innogy, which holds the renewable energy assets of German utility RWE.

In June 2007, the company said it has raised €22 million to-date (see The week's hot solar deals).

ReVolt says its batteries offer three times the energy density of lithium-ion technology and are recyclable. The technology was developed in six years at six years at SINTEF, the largest independent research institute in Scandinavia, before ReVolt spun out in 2004.

Existing metal-air battery technology provides high energy density and low production cost, but ReVolt said it added the ability to recharge the battery for use in high-power applications.

The company says zinc-air batteries avoid problems in lithium ion batteries of thermal runway, in which batteries can become overheated and combust. Lithium ion battery makers including Imara and A123Systems say they’ve begun solving that limitation (see Battery maker Imara emerges from stealth).