You can research as much as you’d like, but when it comes down to it, fixing the battery is pretty simple.

1. Check the voltage of all the modules
2. Load test the modules
3. Identify any suspicious modules and remove them
4. Order at least as many replacement cells, perhaps one or two extra
5. Purchase a battery charger or two
6. Make a power supply for the battery charger
7. Discharge/charge cycle each module 3 times
8. Balance the pack
9. Put it back in your Prius.

Here’s a link to a PriusChat forum that covers it nicely: PriuisChat thread.

Purchasing things should be done ASAP, as some of the pieces can take a bit to ship, and being out of commission for as short a time as possible is ideal. Based off my experience, I think if I were totally ready to go and had everything sitting around, it’d be roughly a week minimum. Pieces that can take a bit of time:

• Battery modules
• Power supply (could be scrounged, which would be a nice way to cut the price of repair)
• Battery chargers

Everything else is pretty easily accessible, so can be purchased locally. Ebay seems to be the place to get the replacement battery modules. I just searched for “2nd generation Prius battery” and poked through the plentiful results.

I got 2 HiTec 44169 X4-80 4-Port Multi-Chemistry Charger as the chargers. They were $120 each, which sucks, but I was in more of a rush than I was broke at that time. If you’re not in a rush, everything can be done with only a single charger – it just takes a lot longer.

I also purchased an EVGA 500 watt PSU (~35$) as a power supply for the chargers. With all of this ordered and shipping, a bit of the stress of the unknown is off.