In all of the "CARB" states like CA, NY, MA all of the emissions components including the battery are warrantied for 15yr/150,000 miles provided that the vehicle is rated PZEV (Partial Zero Emissions Vehicle). You would need to purchase an extended warranty to cover the rest of the stuff up to 75,000 or 100,000 miles I believe.

Good link: http://www.hybridcars.com/emissions.html
You need to be careful when purchasing a hybrid vehicle in a non "CARB" state and then registering it in a "CARB" state because it may not have the required emissions rating for your state.

hope this helped...