[RedDevil]

Originally Posted by sheepdog 44

What capacity do you want the booster pack to be? If you want it to be portable, like you take it out and charge it inside, it can't be very big or heavy. The stock pack i guess is at least 50-60 pounds. If you want to double the capacity you'd need lithium if you want to take it out regularly.

If not a regular 120 volt extension cord might be best plugged into a regular wall outlet both at home and at work.

Thanks, I keep forgetting to put down the essentials.
Your input is more than welcome

I'd want at least 1 kWh, which is doable with 10 Ah LiFePO4 cells which are typically just about 300 grams each, so a 36 cell pack could be as light as 11 kilograms.

In my 22 mile commute I can use about 1 kWh when it discharges at 2C (twice its hourly capacity), 2 kW. That should drop my fuel consumption by about 25%. If all works out as planned.
A larger battery could yield more, but I'm not sure the system would tackle that very well.
Cobb had a 2kW Enginer kit that worked well in his Insight, but problems arose after doubling its power, which is not proven to be the cause but can't rule it out.

We do have 230 Volt here, and 16 Amp fuses. Then, I would not even be bothered by an 8 hour charge time, so no issues there. I'd rather charge slow and safe than fast and reduce battery life.

The bottom line for this project is relative efficiency; improving my economy somewhat on the cheap without compromising boot space much, rather than maxing out no matter what the cost.
I can scale up later.