India’s Reliance Industries led the funding in Massachusetts-based storage developer Ambri Inc. and will set up a domestic manufacturing capability.

The funding is planned to enable Ambri to grow and commercialise the technology and to develop its manufacturing facilities.

Reliance Industries’ subsidiary Reliance New Energy Solar was joined in the financing round by New York investment management Paulson & Co. as well as Ambri’s largest shareholder Bill Gates and new investors including the Japan Energy Fund.

Ambri’s patented technology is comprised of a liquid calcium alloy anode, a molten salt electrolyte and a cathode comprised of solid particles of antimony. It is intended as a lower cost and safer alternative to lithium-ion for long duration energy storage in the range from four to 24 hours.

“This financing supports the commercial growth of our company and technology,” says Dan Leff, Ambri Executive Chairman.

“Further, these funds are instrumental to driving our efforts to scale the company’s operations.”

Ambri intends to use the proceeds from this fund raise to design and construct high volume manufacturing facilities in the US and internationally to meet the growing demand from the grid-scale energy storage market and large industrial energy customers such as data centres.

As part of the transaction, Reliance New Energy Solar will develop and manufacture Ambri’s batteries in India.

Ambri has also entered into a long-term antimony supply agreement with Perpetua Resources, whose largest shareholder is Paulson & Co.

Mukesh Ambani, Chairman and Managing Director of Reliance Industries, says the partnership with Ambri is an important step in the group’s journey of achieving its decarbonisation goals and part of the broader plan recently announced to develop the Dhirubhai Ambani Green Energy Giga Complex in Jamnagar in the western Indian state of Gujarat.

“[This] will be amongst the largest integrated renewable energy manufacturing facilities in the world and the epicentre of India’s Green Economy movement,” he promises.

Ambri’s battery technology is containerised and scalable from 10MWh to over 2GWh and has an expected 20-year lifetime. The systems are considered particularly suited for high usage applications, such as shifting energy from daytime solar generation to evening and morning peak load times.