Is there any difference between batteries for PHEV (hybrid) cars and purely electric BEVs?
Yes, there is. There are fundamental differences in their capacity and design. PHEV batteries have less capacity and are usually located towards the back of the car, under the second row of seats, as the vehicle also has to accommodate an internal combustion engine. The design of BEV batteries, generally reminiscent of a skateboard, is derived from their location in the floor. As BEVs have no internal combustion engine, the battery logically has more capacity.