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Volt gains "Sport" mode and works out some of its noise issues

The 2011 GM Volt is generating unprecedented hype as the highest profile upcoming mass-market electric vehicle.  With the U.S. government and automakers worldwide all betting big on electric vehicles, General Motors has done perhaps the best job at promoting its upcoming vehicle.

The vehicle is currently in the pre-production testing phase, in which the final bugs in the prototypes are ironed out via minor changes, largely to the vehicle's software and mechanical settings.  A fleet of prototype Volts completed a long test-drive journey and engineers are now using the data collected to tweak the Volt.  They hope to minimize its problems in the process.

James Riswick, an editor with Edmunds.com, recently took one of the mules out for a test drive to measure their progress on this front.  He reports, "[The Volt] is sort of on the more fun to drive hybrid.  The suspension is a little firmer, than say, in the Prius, which is on the floaty, comfortable side.  This is not a sports car by any means, but actually the electric power steering is reasonably direct and well weighted."

In his opinion, the noise when driving under gasoline generator is minimal and seems like "white noise". However, when stopping, a more "rough" unpleasant sound was heard – GM says they're working on this issue.  Overall, Riswick says the car is "pretty darn normal" and that "It drives like a pretty nice car"

However, as many have noted a couple of pivotal unknowns remain -- the Volt's finalized real world gas mileage and cost.  The Volt will be available in all 50 states when it debuts, according to GM.  It will be available for around $40,000, plus a $7,500 federal tax credit, which brings it to approximately $32,500 (excluding additional hybrid tax breaks in certain states).  However, this price could be bumped significantly higher or lower still.

The vehicles will currently recharge in about 8 hours household 120-volt current, while special 240-volt charging stations can charge it in only 3 hours.  GM estimates the car's fuel economy to be 230 mpg, but this value has yet to be confirmed in real world independent testing.  One of GM's top priorities has been trying to tweak the gas mileage upwards during the testing cycle.

One detail that has not been widely publicized is the new vehicle's "sports mode".  Activated by a Sport button on the center stack, the feature makes the throttle more receptive and increases its ultimate limit, bumping 0 to 60 mph acceleration down to 9 seconds.  The Volt's urge to scoot increases in the mode, though.  Like most cars, the Volt also provides an electronic version of a "Low" gear similar to that found in normal cars, which allows faster deceleration.  GM recommends the Low mode for driving on slopes or in stop and go.

One disappointment is that the Volt and other Lithium-ion battery-powered electric vehicles may not be viable in hotter climates, such as some states in the American Southwest.  Despite the fact that Volts will be sold in these states, performance may be significantly undermined due to the heat.  Volt Chief Engineer Andrew Farah describes, "The Volt may not be right for everyone. If you live in the Southwest, depending on how you use your car, the Volt might not be right for you."



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RE: Where can you use the Volt?
By Spookster on 11/30/2009 7:08:46 PM , Rating: 3
quote:
by Keeir on November 30, 2009 at 5:54 PM

Sigh.

GM is going to use Active Temperature management. The Batteries will be kept in the correct temperature.

Its not the performance as much as the durability. Charging/Discharging in extreme temperatures results in the loss of total capacity. The Volt charging is designed more with a 40-100 F degree spectrum, but if your a doofus and park your Volt in the Sun at 110 F all day long without a plug (to provide the power to protect the battery) then the Volt's not for you.

Ideal Volt Owner. Someone who travels 30-50 miles per day with a Garage/Power Outlet at home and/or work. You know, like 60% or so of the US


So how are these doofus's as you call them suppose to keep their Volt out of the sun during the day while they are at work? I think unless your place of work provides covered parking or there is a parking garage near your work then that would drop your 60% down to a very small number.


RE: Where can you use the Volt?
By Keeir on 11/30/2009 7:50:17 PM , Rating: 4
Yeah, if you park outside 16 hours a day without a plug in 110+ degree weather for months at a time... thats not too smart with a car sensitive to heat. Especially if you already -know- thats what going to occur.

These Doofus's should buy a Prius or an Insight. Much better than a Volt for them.

To clarify, not Doofus's for parking outside. Doofus's for choose a car that obviously wrong for them.


RE: Where can you use the Volt?
By randomly on 11/30/2009 8:10:05 PM , Rating: 2
The adverse effect of High temperature on the lithium batteries is that charging at temperatures above 40C (104F) starts to increase the rate of loss of battery capacity. Every charge and discharge cycle causes the battery capacity to be reduced slightly. End of life is specified when the battery can only hold 80% of it's original capacity when new.

Charging at elevated temperatures accelerates this wearing out of the battery. At 40C (104F) this is only slightly more than at 20C (68F) but as the temperature goes up this effect increases rapidly. At 60C (140F) the capacity loss per charge discharge cycle is several times higher than at 40C.
Both the Tesla and the Volt actively temperature regulate their battery packs for optimum performance though. They are actively cooled to keep them from overheating. The places you might start having noticeable impacts on these cars are going to be places like Phoenix in the summer time with temperatures up to 120F. Parking the car in the sun under such conditions may start to have a noticeable degradation of the battery pack life. Conditions in most of the rest of the country are not going to be a problem.

It's not so much the car sitting in the hot weather as trying to charge the batteries when they are hot. This temperature effect is also one of the main obstacles to fast recharging. Some Lithium chemistries can be fully recharged in as little as 1 minute or less IF you can keep the battery from overheating during the charging. This is not easy to do when you are dumping such huge amounts of power into them as is needed for fast charging. Very fast charging can be done, but the price you pay is an increased loss rate of battery capacity.


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