Chevy Volt batteries have caught fire. The National Highway Traffic Administration (NHTSA) is investigating, and General Motors has offered to buy Volts back from any owner who fears the electric cars will catch fire.
So does it mean the Chevy Volt is unsafe? The short answer is, no -- Volts won't be spontaneously bursting into flames on our nation's highways. Rather, according to experts we spoke with, the Volt fires prove that automotive engineers have been justified in employing elaborate and expensive cooling systems in their electric vehicles.
Chevy Volt in a side crash test, performed by the Insurance Institute for Highway Safety.
The truth is, there's always been a well-understood fire risk associated with lithium-ion batteries. "The chemistry is edgy," Donald Sadoway, professor of materials chemistry at the Massachusetts Institute of Technology, told Design News in an email. "The electrolyte is an organic liquid that is flammable, highly volatile at even moderately elevated temperature and in the presence of metallic lithium, which can form on the negative electrode at high charging rates."
Elton Cairns, a professor of chemical and biomolecular engineering at the University of California-Berkeley, explains: "In a lithium-ion battery, you've got electrodes that are tens of microns from one another. If you deform the cell case and it causes the electrodes to touch one another, there's an internal short circuit. That can cause the cell to rapidly discharge and, in so doing, heat up."
All of that might sound like a prescription for an epidemic of electric car fires, but it isn't. Why? Because of the aforementioned cooling systems. The Volt employs a fluid coolant that circulates through 1mm-thick channels machined into 144 metal plates that sit between the battery's cells. Using the coolant, the Volt draws the heat away from the core of its big battery.
Similarly, Toyota's Prius PHV, a plug-in hybrid, uses three fans for air circulation, along with ductwork, and 42 sensors to monitor the temperature of its lithium-ion battery. Virtually every manufacturer of production EVs also employs battery management systems and multiple microcontrollers to track the operation of the battery pack at every moment.
of course, they would say that it is safe. who would say that their car products are not safe, right? although based on personal experience, I can say that chevy volt is one of the leading electric cars today. The performance is great and the cost is reasonable. The repairs are easy to do, not to mention their amazing car diagnostic online and repair tips. I just hope that they continue on producing cars like volt and assure people that thair cars are always made with high quality.
dbg your delayed fire comment is true and may be consedered preventable or a non-preventable occurence depending on how handeled. An informed owner may ask for and receive a knowlegeable inspection by a qualified inspector while another owner will NOT exhibt dudilligence and have a delayed fire.
Both WILL probably have insurance. Over time the actuarries will adjust the policies to reflect stupidity and real cost. Other known safety problems such as refuel explosions at gas stations are just as, or more dangerous and exeedingly more frenquent than those of eattery packs.
bdcst Yes agreed, and others fires can be much worse and more spectaluar. Check out windmill fires for instance. But, let me get to the real problem is SAFE ENERGY. Not the battery or buss voltage. How do we get Safe Energy?
The question begs other Qs like what type, where from, at what cost, and the list goes on. Where from, has to be at the top if we want to move on so here is a partial answer that I hope all you young engineers pay attention to thoes flakey old reclusive types and ask the rigut questions. If you do this it WILL lead you to a valley of knowledge that engineering schools don't teach.
So #1 where is this hidden repository?
It is housed in Scientific, Physics, R&D Reports, Patent Offices, universities, corporations, governments, and private;
R&D centers, Labs, Black Ops Centers, Scientific & Physics Libraries History Books, Space......you get the Idea
NOW ask yourself:
Do I have a VERY open mind?
Am I publically closed lipped?
Do I know people with these traits?
Can I be evasive?
Do I have EXCELLENT intution?
Can I calmly hold my own in advanced technical discussion?
Can I exist on little sleep?
If you can say yes to the above you're ready to learn about alternate energy.
Start reading about: Dark, Alternate, Zero, Cold, Quantum, Fusion, Radiant, Transmutation, Energy, New Energy and Matter, etc. Guys like Tesla, Moray, Mallve,Greer, Adamenko,D. Bohm, V. Schauberger,Hubbard, Farnsworth,Barak, Brown, Childress...
These batteries have caused numerous product recalls including thousands of computers and just last month I got a message from Apple recalling my 1st generation, 5 year old iPod due to battery fires!! Apparently as these units aged, they have become more susceptable to initiating fires.
As with all systems, we learn to live with risk managment, by both the provider of the product and the user of the product. However, as systems become more complex, the potential failure modes increase and the reliability decreases. Just remember that the more cells you stuff in a battery and the more electronics you pack around it and its vehicles interfaces, the higher the probability of a failure.
Good point, dgb. Consider this: A gallon of gasoline contains about 30 kWh of energy. That means that a 15-gallon gas tank holds about 450 kWh. In contrast, a Volt battery contains 16 kWh -- equivalent to about half a gallon of gas.
I'm not saying that it doesn't need to be investigated. I'm just saying that we have to put the risks in perspective. Gasoline fires are depressingly common.
We should also note that the fires in question happend a week or two after the damage to the pack was incurred. Most people don't sit in their damaged cars for two weeks.
Alongside gasoline-fueled fires, a big cause of automotive deaths remains distracted driving. According to the National Highway Traffic Safety Administration (pdf download), some 33,000 deaths were caused in 2009 by drowsy driving. I don't know if there are stats yet for accidents caused by texting while driving, but I'd bet the numbers are pretty scary. That said, this stuff as well as gas are discrete from the issues raised by Lithium Ion batteries, which need to be investigated.
That's over 300,000 gasoline vehicle fires per year.
Any time you store large volumes of energy there is the risk of fire. I'd rather be sitting in a vehicle with a well-designed battery pack than a tank full of highly flammable gasoline.
Yes, Hollywood does love its pyrotechnics. Hollywood does twist your expectations. Makes you wonder why more of the accidents you see at the side of the road are not bursting into flames.
We still don't know enough about what happened and when we do, we will report it. But too many times, stories in the newspapers and TV news about such subjects take on the apperance of a witch hunt, then they disappear. Consider Toyota's unintended acceleration "problem." Little was written when Transportation Secretary Ray LaHood said this after the NHTSA investigation: "The jury is back. The verdict is in. There is no electronic-based cause for unintended high-speed acceleration in Toyotas. Period." And what about the infamous General Motors pickup trucks -- the ones that were profiled on NBC Dateline in a story called "Waiting to Expode?" Those vehicles, too, were supposed to be death traps...until it was learned that NBC faked the explosions with remote control explosives. Again -- I repeat -- we don't yet know what happened here. And, yes, there are anomalies. So, yes, government agencies should certainly investigate this fire (or fires, as the case may be). But until we do know anything definitive, I'm siding with the engineers. For the most part, they have a good track record.
A new battery design, which replaces lithium with abundant and low-cost elemental sulfur, is still in its nascent stages but shows real promise for giving batteries more energy potential.
PTC will offer a virtual desktop environment for its Creo product design applications, potentially freeing engineers to run them from remote desktops on a variety of operating systems and mobile devices.
The push to achieving more intelligent, integrated manufacturing is putting a strong focus on networking and connectivity as key enabling technologies.
Now that solar and wind harvesting technologies are a thriving market, researchers are seeking other environmentally related energy sources for which they can create harvesting devices.
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