There's no oil in electric motors.

The only significant oil is for the reduction gearbox, but as it doesn't change gears the wear is very low. First change will pull out some metal I'd guess, quality of machining dependent. Every 60000km/2Y, 1-2 litres.

Batteries may be immersed in a high dielectric thermal fluid, which will experience some breakdown but over a long time period, more than 10Y.