The concept will test the feasibility of a lightweight electric Seven, and is being engineered in collaboration with Swindon Powertrain Ltd.
EV Seven is based on the larger Seven chassis and features a bespoke version of Swindon Powertrain’s E Axle, combined with an immersion cooled battery pack.
It produces 240bhp at 9,000rpm and instantaneous peak torque of 250Nm. This will deliver a 0 to 60mph time of 4 seconds.
Immersion battery cooling uses a dielectric fluid, in this case supplied by long-term Caterham technical partner Motul.
The fluid is in direct contact with the cells enabling better thermal management during charge and discharge cycles.
This technology is typically used to cool super computers that generate enormous amounts of heat.
Bob Laishley, CEO of Caterham, said: “Any future EV model we produce must be true to the DNA of a Caterham: lightweight, fun-to-drive and driver focused. The main objective for this project is to develop a vehicle with a weight delta of no more than the equivalent of having a passenger on board. We’re never going to launch a one tonne Seven – we’d rather not do it.”
Any electric Seven must be useable on both the road and track. For the latter, this means being capable of a repeatable 20-15-20 drive cycle: the ability to drive on track for 20 minutes and recharge in 15 minutes with enough energy to drive for a further 20 minutes.
“Building a Seven that’s capable of a Sunday morning drive is achievable with current battery technology, but the challenge is for track use where the energy consumption is greatly increased. At the moment, immersion battery cooling is one of the best solutions in terms of coping with the rapid charge and discharge cycles that would be experienced on a race track,” added Laishley.
The weight increase is less than 70kg compared to the current production Seven it is based upon (meaning a total mass of just under 700kg).
EV Seven will also benefit from a limited slip differential, adjustable Bilstein dampers from the Seven 420 Cup, regenerative braking and quad-piston brake calipers.
“We do not have plans to put EV Seven into production at this stage - it’s a test bed to see how well an EV powertrain works for our customers’ specific use cases. We’re going to bring this to market at the right time, when the future generation of battery technology allows it,” added Laishley.
The EV Seven concept will make its public debut at Goodwood Festival of Speed in the UK this July.
Caterham is also developing another fully electric sports car concept that it will reveal this year.