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GM's Lithium-Ion Hybrids

At the Geneva Motor Show, GM unveils a new system for improving fuel economy.

Tuesday, March 04, 2008

By Kevin Bullis

Toyota's Prius hybrid has been more successful than GM's hybrid offerings. Today at the International Geneva Motor Show, GM announced its intention to upgrade the battery packs in its basic hybrid system to deliver more power. Maybe that will help improve sales.

GM's basic hybrid system uses a souped-up alternator to add brief bursts of power during acceleration. It runs in reverse during braking, converting some of the kinetic energy of the vehicle into electricity. At best, the system improves fuel economy by 20 percent--just a handful of miles per gallon. But it's less expensive than more sophisticated hybrids like the Prius or GM's new two-mode hybrids, and it can be incorporated into almost all of GM's vehicles. As a result, it could be more widespread. GM plans to make about 100,000 of the vehicles a year.

The new battery pack, a lithium-ion pack made by Hitachi, combined with an improved alternator-generator, can deliver three times more power than the company's older system, which used nickel metal hydride batteries. GM claims that this system will be a perfect complement to another fuel-saving strategy: downsizing the engine and adding a turbocharger for bursts of power. The turbocharger doesn't kick in right away, and it doesn't work well at low engine speeds. But the battery and motor kick in right away, compensating for the so-called turbo lag.

The vehicles will go on sale in 2010. At about the same time, GM will offer two other types of vehicles powered by lithium-ion batteries. The most notable is the Volt, an electric vehicle with an onboard gasoline generator for extending driving range.

In the past, lithium-ion batteries were thought to be too dangerous for large battery packs. But new chemistries (in some cases) and elaborately engineered safety systems (in others) are changing this. Lithium-ion batteries are lighter and more compact than the batteries currently used in hybrids.

Tags: batteries, GM, Toyota, fuel economy, hybrid, lithium ion, turbo

Comments

	Toyota Myth jmaximus9 on 03/05/2008 at 11:33 PM
Posts: 32 Avg Rating:	Everybody seems to think that Toyota makes the most fuel efficient vehicles, but it also makes a lot vehicles that are not so efficient. Take their new full size 2008 Toyota Tundra 2WD, it gets a combined mpg of 17, the 2008 Chevrolet Silverado C15 2WD gets 18 mpg. GM also has the only full size SUV hybrid. GM is not perfect if it can come out with the Volt on time, count me in. Rate this comment: (Reply)

	Re: Toyota Myth verminofmsu on 03/10/2008 at 12:05 PM
Posts: 1 Avg Rating:	You are making discrepancies between 17 & 18 miles per gallon. 1mpg basically equates to a single stomp on the accelerator while entering the highway. Once up to speed, they'll both have about the same gas mileage. Now when dating, there is a big difference between 17 & 18, and that difference is called statutory rape. A good fact to remember for all you pubescent boys. Rate this comment: (Reply)

	The Proof will be in the Bottom Line FreddyG on 03/09/2008 at 7:30 PM
Posts: 5 Avg Rating:	The combined MPG will tell the story. GM's credibility in the hybrid space is pretty weak after their pickup truck entry a couple years ago and now the Malibu that goes from 22 city (gas only) to 24 city (hybrid), where the Camry goes from 21 city (gas only) to 33 city (hybrid). As for the cost, remember that the Malibu or Camry will burn about 8,000 gallons of fuel over it's lifetime (200,000 miles, 25mpg); call it $24,000 of fuel. Cut that by 8%: yawn. Cut that by a third: now that's getting interesting! I'm glad GM is working on it, but gone are the days where GM can sway my perception with advertising; I need to see proof. Rate this comment: (Reply)

	chev price on 03/11/2008 at 12:18 AM
Posts: 1 Avg Rating:	I like Fords' idea of using hydraulic pumps instead of brake pads. It gives the vehicle a real cheap take off power. Japanese vehicles are way expensive and the seats suck... Rate this comment: (Reply)

	Lithium Issues honzik on 03/11/2008 at 2:03 PM
Posts: 4 Avg Rating:	This is a bit tangential, but bear with me. One of the concerns about widespread use of Lithium in the automotive space is that the world supply of the metal may not be enough to handle the demand, or stated economically, that once the demand really kicks in, the price of Lithium might be prohibitively high. I was interested to learn, though, that researchers have come up with a new fluoro-phosphate anode chemistry that would allow Sodium (or a mixture of Sodium and Lithium) to be used in batteries. A good link to this "Alkali Ion" battery technology at Robert McLeod's blog - he's got all of the relevant details. Of course, the caveat is that the battery is in the research phase, but nevertheless, it represents an important direction for new battery technology development. Rate this comment: (Reply)