Safran has become a shareholder in UK-based lithium-sulphur battery specialist Oxis Energy as part of an effort to mature the technology for commercial aircraft.

Without disclosing financial details, Safran says its corporate ventures division made a contribution to a £7 million ($9 million) funding package for Oxis, which also includes investments from Brazilian technology fund Aerotec – an existing shareholder – and French chemical group Arkema.

The funding package raises capital at Oxis to £24 million and will be used to commercialise and automate mass production of lithium-sulphur batteries, Safran says.

Samsung Ventures previously invested in the Oxfordshire-based business, while its largest shareholder is South African energy and chemistry group Sasol, Oxis says.

As part of the deal, Safran and Oxis signed a joint development agreement to devise battery systems for commercial aircraft.

"This technology co-operation is emblematic of Safran's strategy in hybrid propulsion solutions," says Alain Sauret, chief executive for the group's electrical and power division.

He says the manufacturer is "considering the future use of Oxis cells in some of its products in order to offer a level of performance that sets us apart from the competition".

Separately, Oxis signed an agreement with Arkema to work on improving battery lifetime and energy density.