Reliance Industries, India’s largest private sector company, has announced a Rs 370 cr bet on a technology that aims to rival the dominant Li-ion technology for stationary and large-scale applications.
The company has invested $50 mn in a US-based startup, Ambri, to in exchange for an unspecified stake in the company.
Ambri, which started out as a research project in Massachusetts Institute of Technology, is focused on building alternative, liquid-based electricity storage systems that can help reduce the dependence on Li-ion batteries.
Traditionally, rechargeable batteries were based on liquid technology, and were called lead acid batteries. However, using lead acid batteries also means losing about 15-20% of the total energy in the form of heat.
Because of this, companies prefer to use Li-ion batteries, even for applications where space and weight is not a constraint, such as solar power setups inside office buildings.
However, Li-ion batteries, which offer 98-99% charging efficiency, are notoriously costly due to the paucity of lithium as well as the difficulty of mining it.
In addition, most of the Li-ion batteries are diverted for weight-and-space constrained applications, such as mobile phones and electric vehicles, as they offer much more charging capacity per unit of space and weight compared to alternatives.
Ambri, on its part, is not trying to displace Li-ion batteries in such mobile environments, but is focused on providing an alternative in use-cases where space and weight are not a big constraint, such as stationary power backup.
It is also trying to reduce maintenance costs of batteries. Li-ion batteries, for example, are solid-state devices and therefore need to be protected from overheating using proper cooling infrastructure. Liquid state batteries, on the other hand, easily get rid of heat through the circulation of the electrolyte inside.
Ambri, on its part, is focused on calcium antimony batteries that use electrodes built using these two elements.
Calcium antimony batteries are “containerized systems that are more economical than lithium-ion batteries” and are capable of operating safely in any climatic condition without requiring supplemental air conditioning, Reliance said.
It added that Calcium Antimony batteries can last for over 20 years with minimal degradation. In comparison, lead acid batteries degrade fast after a couple of hundred discharge cycles.
RIL said Ambri’s systems are particularly suited for high-usage applications, such as shifting energy from daytime solar generation to evening and morning peak load times.
“Based on patented technology and designed to last between 4-24 hours, Ambri’s long-duration energy storage systems will break through the cost, longevity and safety barriers associated with lithium-ion batteries used in grid-scale stationary storage applications. They will enable a crucial energy storage solution capable of supporting the increasing amounts of renewable energy being integrated into electric power grids,” the Indian company said.
The Ca-Sb technology is considered mature enough that Ambri has got contracts to construct such batteries for large-scale projects that start commercial operations in 2023, RIL said.
Reliance, which generates most of its current revenue from the hydrocarbon sector, has been on the lookout for opportunities in the green energy segment, even though it has not been a pioneer in either the wind energy sector or the solar sector.
However, it is trying to make up for lost time with more and more investments in this area, particularly in end-user applications.
As part of the investment and partnership, said RIL, it is in talks with Ambri for an “exclusive collaboration to set up a large-scale battery manufacturing facility in India” using the US company’s technological know-how.
It added that Ambri’s technology can break through the cost, longevity and safety barriers associated with lithium-ion batteries used in large-scale applications.
“They will enable a crucial energy storage solution capable of supporting the increasing amounts of renewable energy being integrated into electric power grids,” said the Indian company.
The group will invest $50 million to acquire 42.3 million shares of Ambri as part of the current transaction.
Other investors in Ambri include Bill Gates, Khosla Ventures, KLP Enterprises, TOTAL SE and GVB.