During an information-heavy battery and technology update on the Chevy Volt's progress recently, GM said the following about the 16 kWh battery pack in the plug-in car:
We understand that outside temperatures can have a big impact on how a battery operates and will affect the Volt as well, but the good news for Volt fans is that Green Car Advisor got it wrong. They said that hot weather Volt owners will get less than ten years of life from the pack, saying Volts in "many parts of the western and southern U.S." would not get "the normal 10-year life of the battery." Not true, says GM, which is confident that everyone will get 10 years from the pack. GM's hybrid and battery technology communication spokesman Brian Corbett told AutoblogGreen that, "in more moderate areas of the country, battery performance could last beyond 10 years. 10 years is our minimum target life for everybody.""The biggest challenge in testing is hot-weather storage of the vehicle. Currently, ten years of battery life is the norm, but some people could get more battery life depending on the climate where they live and their driving conditions.
[Source: GM via Green Car Advisor]