Kia will reveal the Optima T-Hybrid concept at the 2014 Paris Motor Show on October 2, the first application and demonstration of the brand’s innovative new mild hybrid powertrain.
The concept is powered by the model’s existing 1.7-liter CRDi turbo-diesel engine, paired with a small electric motor, powered by a 48V lead-carbon battery. The diesel-electric powertrain enables the Optima T-Hybrid concept to be driven in electric-only mode at low speeds and when cruising, with deceleration serving to recharge the battery pack.
Lead-carbon batteries were chosen for the mild hybrid powertrain as, unlike lithium-ion batteries, they require no active cooling and are easier to recycle at the end of the unit’s lifecycle.
The car features a zero-emissions stop-start system, and a new belt-driven starter generator replaces the conventional alternator, meaning the engine can restart with almost no noise or vibration. Installing the powertrain in the Optima sedan has enabled engineers to fit a smaller vehicle battery and starter motor, enhancing weight distribution and handling.
The system also allows the installation of an innovative electric supercharger for the CRDi engine, in addition to the conventional turbocharger, providing improved power and torque at all engine speeds. The electric supercharger in particular helps to boost torque and engine response at low engine speeds.
Still under development, no specific performance or fuel economy figures are confirmed for the powertrain or its application in the Optima T-Hybrid concept. However, Kia’s engineers are targeting a significant reduction in CO2 tailpipe emissions and fuel consumption and a power increase of between 15 to 20 percent for any model which could be equipped with the new powertrain. Currently, the Optima’s 1.7-liter engine produces CO2 emissions of 128 g/km (when fitted with ISG stop-start).
The Kia Optima T-Hybrid concept is still in development and a decision regarding production is pending.
