Toyota warranties all their hybrid"s charing emissin and battery systmes for 8 years or 100k miles
http://www.toyotacertifiedhybrids.com/warranty.html
In CA That increases to 10 years or 150k miles (and all other states following CA emissions) and the replacement costs range from about $1,500 to $3,000
http://www.consumerreports.org/cro/n...ries/index.htm