Mahle Powertrain and Allotrope Energy have unveiled a new battery technology which they say offers ultra-fast recharging and good power density.

By combining supercapacitors with traditional lithium-ion batteries, the lithium-carbon technology enables a full charge to be delivered in a similar time to refuelling an IC-engined vehicle. In addition, the lithium-carbon cells do not use rare earths, are fully recyclable, and are not susceptible to thermal runaway.

Allotrope and Mahle looked at how an electric moped could be used as an urban deliveries vehicle with a target range of 25 km and powered by an inexpensive small-capacity lithium-carbon battery that could be recharged between stops in as little as 90 seconds.

They found that a 500 Wh conventional lithium-ion battery would require a recharge mid-shift that, even with a fast-charger, would take more than 30 minutes.

The technology features a high-rate battery-type anode and a high-capacity electric double layer capacitor-style cathode, separated by an organic electrolyte.

The result is said to be a battery that suffers from none of the thermal degradation effects experienced by traditional lithium-based batteries. Its stability, even at high temperatures, permits high current delivery and fast recharging, all without the need for complex external cooling or elaborate battery management systems.

Also, its capacitor-style cathode is said to have a lifetime of more than 100,000 cycles.

The technology uses its own built-in capacitor-based energy store to deliver ultra-fast charging up to 20 kW by augmenting the power from a typical 7 kW single-phase connection.