The Spark EV battery's energy density is 90 Wh/kg (versus 137 Wh/kg in the Bolt EV's battery). Would you be willing to give up 33% of your battery capacity (range) so that you can charge at 2.5 to 3 C? Essentially, a 160 mile car?Chevy Spark EV. (Charge Rate expressed in C : about 3C max.) Had the Bolt used the battery and cooling tech available in the Spark, it would have charged somewhere around 150-160 kW (2.5C, 60 kWh)
Also, I believe that would result in a more expensive battery, despite the lower energy capacity.
Everything has trade offs.