How much does the ICE charge the battery?

PiP can recharge the entire EV range through regen braking, but the ICE is not used to recharge the entire EV range*. In HV mode PiP acts pretty much like a non-plugin GenIII, with the ICE recharging only a reserved portion of the battery that is similar to GenIII's traction battery capacity.

*There are some exceptions, but they're rare. Whenever conditions force the ICE to run, excess generation goes to the battery. The same thing can happen in the normal GenIII, where the ICE may help recharge the battery before it is depleted. But the rule holds that the ICE isn't run for the purpose of recovering EV range.

 

When you hit HV, the gasoline engine is used to hold the current battery charge level. So some folks resort to a strategy called "stacking", where you switch to HV mode when going up hills (using the gasoline engine and not draining the battery), adding the regenerated power to the battery on the way down, and toggling to EV and back to HV before you need power, to establish a new, higher, state of charge level, which is maintained by the gasoline engine. This effectively is using the gasoline engine to recharge the battery. But it escapes me what the point would be.

 

That is my understanding.

 

i managed to use a bit of battery in hv by driving very carefully and when i came to a light, the engine came on and restored some of the charge. i don't think this is efficient tho and you're probably better off driving normally in hv.