[h=3]I found following information on a website, hybridcars.com
Hybrid batteries need to be replaced.[/h] Worries about an expensive replacement of a hybrid car's batteries continue to nag many potential buyers. Those worries are unfounded. By keeping the charge between 40 percent and 60 percent?never fully charged, yet never fully drained?carmakers have greatly extended the longevity of nickel metal hydride batteries.
The standard warranty on hybrid batteries and other components is between 80,000 and 100,000 miles, depending on the manufacturer and your location. But that doesn't mean the batteries will die at 100,000 miles. The U.S. Department of Energy stopped its tests of hybrid battery packs?when the capacity remained almost like new?after 160,000 miles. A taxi driver in Vancouver drove his Toyota Prius more than 200,000 miles in 25 months, and after that time and mileage the batteries remained strong.