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Prius(2004) hybrid battery - rebuild?

Can the Prius hybrid battery be rebuilt safely and economically without special tools?

I remember hearing about operations that would rebuild a regular car battery by cutting out and replacing a defective cell, but I doubt tht it was cost effective. It certainly took some special tools. The Prius hybrid battery is certainly more sophisticated and it isn’t something that could be rebuilt without special tools. There may be factories that rebuild the Prius battery, but a person off the steet can’t do this.

When a CELL fails in a Prius battery, first, the failed cell must be located, then removed and replaced. Toyota dealerships have been trained in how to do this. I don’t think it’s a DIY project…

In the beginning, they replaced the entire battery with a new one, but that got too expensive. Now they ferret out the bad cell and replace it…There is something like 150 cells in the pack…

Yes,if you have 1 or more batterys in your pack that are bad they can be replaced with out any special tools.There are 28 batterys in the 2004 and up Prius’s pack and 38 in the 2001-03 pack and they have differant chemistrys.Check each battery in your pack they should all be very close in voltage the ones that have a lower voltage are the bad ones.People sell good used ones on ebay.Be careful battery packs are over 200 volts

I’d sure want some very specific instructions before I go messing around with a 200v battery pack. That’s plenty enough to kill.

The June 2010 issue of Home Power magazine has a VERY detailed description of rebuilding the hybrid battery pack for a Civic Hybrid. It looks somewhat involved, but definitely doable. The safety issues only come up at the very first part of the process, and don’t appear to be a problem as long as you pay attention.
Total cost including buying a charger and getting replacements for several of the NiMH cell sticks (8 cells prefabed together) was $380.
I suppose there must be something similar out there for the Prius.

Batteries DO NOT “wear out” one cell at a time…With a 2004, 6 or 7 years old, the entire battery pack is nearing the end of its service life. Installing new cells in an old battery is a waste of time and money…

If you can’t afford to replace the entire pack, locate a USED pack or group of cells from a car of similar age and mileage and used THOSE cells to “rebuild” your failing battery pack…

Had my 2001 Prius in in march for a battery replacement (under warranty) they replaced the entire unit although only one cell was performing under spec.