HI! I read an article at my local chevy dealer that stated it was cheaper overall to own a Hummer. It went on to say that Toyota builds the Prius with nickel in the battery. The cost of mining the nickel, shipping it and the smelting process was more expensive than just owning/operating a Hummer. The figures also stated that the battery life expectancy is only 100,000 miles. My question is this: How much does it cost to replace the battery? I am looking at hybrid vehicles, but I do not want one that causes environmental harm just to produce the battery. Does mining the nickel do more environmental damage than the Prius can make up for? I am looking carefully at everything that hybrids offer, and may just end up not buying one at all. Anything helpful will help!! Thanks!