The continuous increase in BEV sales worldwide requires more public charging stations at various strategic locations. The addition will require more time, capital investments, resources, land and electricity. Alternatively, a simple and cost-effective range extender engine is needed. Such engine must also be compact, lightweight, efficient and clean burning for easier adoption by existing and near future BEVs. With this end in mind, a fixed speed and load HCCI engine preliminary concept is proposed. The obvious narrow operating range of HCCI combustion limitation is mitigated by matching it with the optimal operating speed and load of the onboard electricity generator. To address the changing ambient and engine operating temperatures, a novel control strategy is combined with extra long intake manifold. This long intake manifold enables relatively steep increase in volumetric efficiency from 1,500 to 3,500 engine rpm. With no throttle body used, the steep increase enables the desired intake charge mass to be varied by changing the injected fuel mass to alter the engine speed. Using the ideal gas law, accurate cylinder temperature to timely auto ignite the intake charge for Maximum Brake Torque (MBT) is possible by varying the charge mass. To ensure continuous MBT in the presence of unavoidable variations like ambient and engine operating temperatures, engine wear, parts variations, viscous losses, etc., a unique and simple close loop control strategy is also proposed. In the absence of actual test data, this paper relies on various engineering theories and principles supported by earlier work by others to outline the step-by-step approach to make the concept a reality. This paper also covers the preferred engine architecture and its integration into the BEV. Expected research challenges, white space and opportunities to be explored are also included to encourage further research in this new area.