Re-charging PiP traction battery while driving

100% of usable charge, I think Toyota has upper and lower limites to protect the battery, non usable to us as owner's.

 

Basically if you want to get your EV range back, you'll need to use a long downhill. If you just want the HV range of the battery to be fully charged (all 8 bars showing), normal driving will do that.

 

I just had a very cool happenstance yesterday.
It was hot as Hades... got up to 108 middle afternoon.
I had errands to run out in the inland empire... so I hit the road to Ontario first @ 11am. I did my errand at ULINE and got back to the freeway on the 60, went to the 15 South to Corona (Tom's Farms) and spent some time there. I headed south to the 74 (Ortega HWY) home at about 2:30 and took the Ortega home... and midway thru the Ortega, I realized the EV light had popped up on the dash and said: 1.4 miles (huh?!) and I had not even plugged it in all day. It was drained when I left home Sun morning, forgot to plug 'er in night before)
and I was on the curves with braking and downhill... and managed to get 8.6 miles with the AC on blasting, using absolutely zero gas. I had company in the car and we were both shocked, marveling at this, also watching to see if the red arrows popped up at all... and I calculated with the car's trip meter as my braking and downhill and curves managed to sustain my speeds and battery time. It felt like forever! It was cool.