Sulfur-based battery firms attract funding

Two firms vying to develop lithium-sulfur batteries, which could be more energy-dense and cheaper to make than today’s lithium-ion batteries, have received major boosts to their funding.

Baseload Renewables, a 2017 spin-off from MIT, has raised $7.4 million from an undisclosed investor. Baseload will use the money to advance its lithium-sulfur flow batteries, which are designed to meet demand spikes on electricity grids.

Baseload’s batteries feature cheap, readily available sulfur dissolved in water as the anode. The firm anticipates that its technology will enable batteries to be made for between 10 and 20% of the cost of equivalent lithium-ion batteries. The firm raised almost $2 million from MIT’s technology incubator, the Engine, when it launched last year.

Meanwhile, U.K.-based Oxis Energy, a developer of batteries featuring a lithium anode and a sulfur-based cathode, says it will receive $5 million from Aerotec, a Brazilian private equity fund. The Aerotec investment will enable Oxis to set up a subsidiary and R&D center in Brazil.

But not all lithium-sulfur technology development has gone as planned. Sion Power, a battery materials start-up in which BASF invested $50 million in 2012, tells C&EN it has shelved its lithium-sulfur research.

“It was a technology decision,” says Sion’s marketing director, Angela Kliever. The firm is now pursuing lithium-ion battery technology featuring a lithium anode rather than the usual carbon anode. With 450 charging cycles, the lithium anode technology can handle an order of magnitude more cycles than the firm’s lithium-sulfur anode technology. “The decision we made was all about the numbers,” Kliever says.