Red Bull Technology, a branch of the Red Bull Group, is understood to have put its name to a tender for the new Formula E battery set to be implemented for season five of the all-electric series.

RBT has expressed interest in supplying teams in the series as it looks to expand its motorsport portfolio.

The Milton Keynes-based company is believed to have posted a tender to design and build the new units, which are set to be increased to a useable energy of 54kW/h with a maximum power of 250kW.

Should RBT be successful in the tendering process, it would have to supply all of the teams from 2018 onwards.

The plan for the new battery sees it being initially crash tested next June before a test battery will become available to teams in November 2017.

The car, complete with battery, must be homologated in June 2018 before testing commences. A collective test is provisionally scheduled for August 2018.

The initial decision from the FIA on who the successful bidder for the contract is was originally intended to be made public in June.

However, understands that the number and quality of applicants was so high that additional time has been sought in the last six weeks for the FIA and technical consultants to go through each in forensic detail.

The current battery supplier, Williams Advanced Engineering, has been joined in the new tendering process by Renault, DS and Mahindra, as well as several other notable applicants.

Red Bull has had some footprint in Formula E through Sebastien Buemi and Antonio Felix da Costa, who both retain backing from the company. Dr Helmut Marko also attended the 2014 Punta Del Este ePrix in an advisory capacity.

A decision on which of the contenders will be successful for the battery tender could be formalised between the Donington Park test sessions, which start on August 23 and September 5 respectively.

Formula E faces crucial battery decision spoke to a leading technical director in Formula E to gauge what the FIA and teams are looking for in the new battery supplier.

“Technical due diligence on the sheer number of batteries is really tricky to do at this stage,” said the source, who wished to remain anonymous.

“To assess all the companies you have to go and visit them and understand what they have done in great detail, what they will do and show us how close you are. You really have to commit early because the timescale is so tight.” understands that the teams are concerned they have not been more directly involved in discussions regarding requirements for the season five batteries.

Formula E faced difficulties in its initial battery partner before the start of the series in 2014, when Williams Advanced Engineering proved to be the effective saviour of the championship.

“The crash test requirements and all the safety requirements are way beyond what is done with a monocoque,” added the source.

“Structurally it is very sub-optimal, so just the specifics of the shape have to be considered very carefully. We [the teams] need more say in the decision alongside consultants being used to go through everything.

“A lot of us think it will be the same as season one, in that the battery will be the limiting factor. Remember all the issues with the original supplier then? It could be the same again, despite the quality of the choices on offer this time.

"Scaling up is very tough and you have to say Williams would be the safe bet because of their experience, and the simple fact they did a very good job in very tricky circumstances.

"But then again there was a lot of disquiet about their involvement with Jaguar, so there is a lot to discuss and time is not on anyone’s side.”

Red Bull outside bet

RBT is being seen as an outside choice for supplying the battery for season five, due to a potential conflict in both experience and branding as a supplier.

Red Bull is a surprise but what it shows is that Formula E is attracting some really big names,” continued the senior engineering chief.

“They would do a good job I’m sure, but I think it is unlikely the teams will be completely comfortable, because it limits potential commercial deals for us in the future, especially in terms of embracing other energy drink partnership possibilities.”

Gallery: Red Bull Technology bids for Formula E battery deal