Swiss membrane-free redox flow battery company lands $17m early-stage funding

Swiss startup Unbound Potential has announced it intends to have a pilot project demonstrating its membrane-free redox flow battery technology by mid next year.

The Thalwil-based company says that its redox flow design keeps costs low as it scales. It removes costly membranes and intricate cell stacks and works with two immiscible liquids and minimal hardware.

The technology is built to last more than 20,000 charge-discharge cycles with up to 85% roundtrip efficiency.

Unbound, which said it is also in talks with Amazon about its energy storage system, made the announcement after securing €14.4 million of early-stage, “pre-seed” funding to commercialize its idea.

Unbound on Friday said it had secured €8 million of “non-dilutive” grants – for which it does not have to surrender equity – plus “around” €6.4 million of conventional investment.

Antonia Albert, principal at Zurich-based pre-seed funder Founderful, which has invested in the startup, said, “Unbound Potential has created the simplest, fastest-to-produce battery in the world.”

The non-dilutive grants are likely to have come from German federal innovation agency SPRIN-D; Swiss public innovation body Innosuiss; the Migros Pioneer Fund set up by Switzerland’s biggest retailer; and the city of Zurich’s KlimUP, climate-focused startup backer.

Conventional investment was led by Founderful, with Helsinki-based venture capital fund Kvanted as co-lead investor alongside the canton of Zurich-owned Zürcher Kantonalbank.

Announcing the investment, Unbound founder and CEO David Taylor said, “We have completed one of the largest pre-seed financing rounds in Europe. The round is a decisive step for us as a company and a strong signal for our vision of a future based entirely on renewable energies. With the capital, we can now accelerate the development of our membrane-free redox flow technology and demonstrate its scalability in initial pilot projects.”

Unbound also said it is in talks with Swiss technology consultant FlexBase Group, which is developing an 800 MW/1.6 GWh redox flow battery at Laufenburg, in its homeland.