My :jawdrop: idea for stretching out the Prius gas mileage to 75 to 100 mpg without spending $8k to $24K for an aftermarket kit or job is to:
1) buy a replacement Prius NiMH battery pack from Ebay where they have them for $800 to $1100. Install it in parallel with the stock battery. Be careful and wear gloves as I've heard the car battery has 288 volts.
2) Install the EV-only switch to the switch blank on the left side of the dash described and pictured here in a PDF.
Since the Prius BMS is designed to override the EV-only instruction whenever the battery falls below 80% charge, the gas engine (ICE) may try to run to recharge it. Try to handle that by installing:
3) manual ignition defeat switch on the ICE starter. I suppose that ignition failure could cause computers to shut off the EV motor, but probably not.
Alternatively, buy the aftermarket BMS replacement box from Hybrids-Plus in Boulder, CO
Then if I know I only want to go 25 miles or less at 34 mph (the governor limit Toyota puts on the EV motor) I won't over-deplete the batteries.
Now I just need a battery charger for a 288 volt battery to plug into when I get home. Where can I get one of those?
Any ideas or experience here, guys?
Bob in San Diego