Abstract: This invention presents an innovative technology, dedicated hybrid cycle, for dual piston based engines, which can be further developed as mobile chargers for electric vehicles. This design re-defines the single engine piston/crankshaft configuration in conventional internal combustion engines as two sets per the combustion process: Otto piston and Atkinson piston; correspondingly, there are Otto crankshaft and Atkinson crankshaft. As a matter of fact, the Atkinson crankshaft can be realized through a cam as well. The Atkinson mechanism is dedicated to accomplish high combustion efficiency, while the Otto crankshaft for engine output only. Periodically, the hybrid combination of both Atkinson and Otto cycle can significantly improve the engine efficiency and torque density. This innovative combustion mechanism is further developed for genset applications to generate electricity on the vehicles in a most efficient manner.