General Motors has committed to lithium-ion technology for all of its future battery applications in hybrids, plug-ins, extended-range electrics, and fuel cell vehicles. The company has “no future plans to develop nickel-metal-hydride batteries,” according to lead battery systems engineer Andrew Leutheuser.
Lithium-ion batteries have roughly two times the energy density of the nickel-metal-hydride batteries found in hybrids today. That means engineers can retain the performance of existing battery packs while cutting weight in half. Most auto manufacturers intend to use lithium-ion batteries in their newest products, but some are hesitant to abandon the large financial investment already made to put nickel-metal hydride in existing hybrids.
Following the Volt’s launch in late 2010, GM will introduce its second-generation belt-alternator hybrid system using lithium-ion batteries. GM won’t state what vehicle the new lithium-ion system will first appear in, but said the vehicle will launch in 2011 and hinted that it will likely be a sedan. That time frame means the hybrid system will launch before a face-lifted Chevy Malibu in mid-2012, leading us to believe the new BAS will debut in a Buick.
While the energy capacity between the new and old batteries is essentially the same, GM expects to see a 12- to 15-percent boost in fuel efficiency with the second-generation technology. For a midsize sedan, that could mean fuel economy around 29 mpg in the city and 38 mpg on the highway. The belt-alternator system, sometimes called a “mild hybrid,” is currently used in the Chevrolet Malibu, Saturn Aura, and Saturn Vue.
In addition to the belt-alternator system, the upcoming plug-in hybrid and next-generation two-mode hybrid systems will use lithium-ion batteries. -Eric Tingwall