Prius Battery Information

The Prius's fuel efficiency ratings account for much of the vehicle's popularity. It regularly leads the list of most fuel efficient vehicle in the United States.

Prius's battery pack, a nickel-metal hydride battery (Ni-MH) also contributes heavily to its fuel economy ratings.

The battery sits under the cargo space and helps power the car. According to Toyota, "A full hybrid recharges the hybrid battery during operation, so it doesn't need to be plugged in for recharging. The batteries also recover energy back from the drive train in a process called regenerative braking. Regenerative braking is a mechanism that reduces vehicle speed by converting some of its kinetic energy into a storable form of energy instead of dissipating it as heat as with a conventional brake. The captured energy is stored for future use."

The hybrid battery should not be confused with the 12v accessory battery that is used to power accessories such as the lights, fans and radio.

Finding detailed information about the Prius battery can be as easy as doing an Internet search. Often the searcher will want to know about the battery's reliability.

A discussion of the Prius battery starts by noting that the Prius has gone through three design phases, often called Prius Generation I (1997 - 2003), Prius Generation II (2004-2009) and Prius Generation III (2010-current).

Prius currently states 150,000 miles as the life expectancy of Prius Generation III batteries, with 100,000 miles given as the battery warranty, except in CA, where it is 150,000 miles.

While the Prius sites on the Internet provide anecdotal information about Prius battery reliability, Toyota itself does not provide statistical information on battery reliability. So, of the one million Prius sales, we do not know if 10% of those cars (100,000) or 1% of those cars (10,000) have experienced battery problems.

The best guess on reliability would be somewhere less than 10%, otherwise it sounds reasonable that the Prius sites would have many more battery complaints. But that's just a rule of thumb, and not a statistical analysis.

At year end 2008, Toyota announced a new pricing scheme for replacement batteries.

"The MSRP for a battery pack for a first-generation Prius is $2,299, while the MSRP for the battery pack for the second-generation cars, those from the 2004-2008 model-years, is $2,588. This reflects three price reductions for the first-generation battery since it was introduced and two price reductions for the second-generation battery. Naturally, labor charges, which are set by each dealer, as well as possible charges from ancillary parts that could be required, should be added to that figure. Finally, we assume responsibility for recycling all of our hybrid batteries."

© 2011. Patricia A. Michaels