A good friend started pulling out the battery from his Prius today. Apparently he has been having problems with it for the last 50K, but wasn't sure what the problem was. Two weeks ago I was with him and a warning came on the dash screen. Soon after that the car stalled. He has checked out the problem and it is the main battery. He plans to buy a rebuild one for about $2000, he hopes. The car is a mid 2000 model with 213K, but like I said there have been problems for some time. Will try to keep you up-dated if I can. Also this is the second Prius battery failure of friends I know in the last month.