i'm hearing any where from a couple bucks for the key fob to a hundred or two for the 12v to a thousand and more for the drive battery depending on new, used or rebuilt.
Replacement of the HV (200v) traction battery is rare within the warranty period, but is beginning to occur in older Prii. My 2004 battery failed at 194,000 miles about 2 months ago. The options were: 1 - A new battery at the dealer $3300 2 - A rebuilt battery from ReInVolt (NC) at $1475 plus $125 shipping and $400 installation 3 - Rebuild my own battery about $100 for extra modules and charging equipment, but the month+ downtime to rebalance all of the modules was not feasible 4 - Buy a salvaged Prius battery for about $600 but the quality is questionable I went with the ReInVolt option for $2000 and after rebalancing/charging my old modules (only one of the 28 has failed) I will sell them on eBay for about $30 each plus shipping. JeffD
