Korean carmaker Kia will showcase its new diesel-electric hybrid concept at the Paris motor show this week.

The hybrid concept is based on the brand’s Optima sedan and is dubbed T-Hybrid. It also uses the Optima’s existing 134bhp 1.7-litre CRDi turbodiesel engine with a small electric motor.

The resulting concept can be driven by an electric power only at low speeds and while cruising, using a lead-carbon battery recharging via deceleration. Kia says it chose a lead-carbon battery over more conventional lithium-ion units because they require little cooling and can be easily recycled.

Kia first previewed the technology at the Geneva motor show earlier this year, saying the system would be offered in both petrol and diesel-powered models “in the near future” to help lower CO2 emissions, while also raising power.

Other new features fitted to the concept include a new belt-driven starter generator, which replaces the conventional alternator, and can start the Optima T-Hybrid concept with zero emissions, as well as “almost no noise or vibration”. A smaller vehicle battery and starter motor are also fitted.

Power from the 1.7-litre CRDi engine is also said to be enhanced thanks to a new electric supercharger, which works alongside the existing turbocharger to improve peak output and torque. The electric supercharger particularly increases engine response at low speed, says Kia.