How to Get the Most Life from Your Car's Lithium-Ion Battery Pack

The recent problems surrounding the Chevrolet Volt plug-in hybrid have brought to light an issue not often considered in the purchase of a hybrid vehicle -- that of caring for the car's lithium-ion or nickle-metal hydride power source. While battery manufacturers such as Compact Power, Inc, supplier of the Volt's battery packs, and Panasonic, future supplier to Toyota's Prius, have built largely maintenance-free batteries, that doesn't mean that consumers should just plug in, and then forget the battery packs in their hybrid cars.

Now that some hybrid vehicles are approaching ten years old, there are a greater number of them that are being seen on the secondary market. While owners who buy new hybrid vehicles don't have to be concerned about the batteries in their cars, second owners have reason to be wary. In California, Massachusetts, Maine, New York, Rhode Island and Vermont, state law requires automakers to provide consumers with a 150,000-mile warranty on the battery packs of hybrid vehicles. Such laws have not been enacted in the remainder of the United States, however. Basic warranties may cover the battery for just eight years and 100,000 miles. Since many first owners trade in their vehicles at or near this point, no additional warranty coverage is then offered to the second owner.

That doesn't mean that a hybrid plug-in vehicle is no longer any good, though. New Lithium-ion batteries are easy to keep in good condition, and will usually last well in excess of 200,000 miles without replacement. Nickle-metal Hydride batteries require slightly more care to run for extended periods.

Lithium-Ion

Lithium-ion hybrid batteries aren't like the battery in your laptop or smartphone. They use what is called an intelligent battery management system to ensure that all the individual cells of the battery pack function the way they are supposed to. You should avoid completely discharging these batteries due to the fact that there is a protection circuit that will be tripped if the charge falls below a specified level. Continually running the batteries down to their lowest level is a sure way to shorten the life of these battery packs.

While charging, a vehicle that is powered by a lithium-ion battery pack should be kept at a consistent temperature. Temperature extremes such as those below freezing or above 122 degrees may result in damage to the batteries.

Nickle-metal Hydride

NiMh batteries require slightly more care to maintain their charge, but they can still run for extended periods with this care. While charging, avoid disrupting the charge cycle as much as possible. This results in heat buildup in the battery. Also, the battery generally has to be discharged every three months or so, according to the maintenance outlined in your vehicle owner's manual. Adhere to these discharge periods so that you'll get the most life out of your battery pack.

All Batteries

All hybrid vehicle batteries use forced air blown through or over the batteries to cool them off and maintain their performance. The fans used for this have intake ducts, behind which are air filters. In order to maintain battery efficiency, inspect these filters once per year to ensure that they don't have too much dirt in them, clogging the flow of air. Regardless of whether you buy a new or used hybrid vehicle, keeping these battery longevity tips in mind will help save you time and money, and keep your hybrid running like new for years to come.

Sources:
Panasonic press releases: "Panasonic Group to Supply Lithium-Ion Batteries for Prius Plug-In Hybrid": panasonic.net
Consumer Reports: Guide to Hybrid Cars: www.consumerreports.org
Hybrid cars: The Hybrid Car Battery: A Definitive Guide: www.hybridcars.com