The previous model Prius (sedan often called "classic") has been sold in US since 2000, as a 2001 model. The high-odometer poster I see in the Yahoo groups is Eric Metzler who has 191k miles. He said his gas mileage has not decreased, which is one plausible side effect of a HV battery with reduced capacity. A few others check in from time to time with more than 100k miles, but not saying "I just bought a new HV battery". Not that it could not happen, but it appears to be very rare.

The new model Prius has a redesigned battery; nothing about the change makes me suspect that the HV battery will fail sooner.

The numbers tossed around for HV battery replacement cost seem to be in the $2k - $3k range, but one recent new model Prius free battery replacement under warranty had $1100 printed on the paperwork. One could just call a Toyota shop and ask them the price.

If I ever need a HV battery for my 2001 Prius I will probably look to the salvage market. Prius "crash out" of the fleet sooner than they suffer major component failures. I am hoping for 300k miles / 500 k kilometers.

DAS