It's mostly the battery cost. Originally the battery cost roughly the same as the rest of the car, and for a battery that would be considered small by today's

It's mostly the battery cost. Originally the battery cost roughly the same as the rest of the car, and for a battery that would be considered small by today's standards. And since then the battery costs are coming down due to mass production. This has been predicted in theory for about a decade with 100 dollars per KWh at the cell level being the crossover point where up front costs of EV are lower than ICE. This has already occured in China.