Burnt 2011 Chevy Volt

Chevy Volt fire: What did NHTSA know and when did they know it?

The NHTSA released a detailed report of the Chevy Volt crash test and forensic investigation last week prior to this weeks House Oversight committee hearing.

On Wednesday this week the House Oversight Committee will take up the question, "Volt Vehicle Fire: What did NHTSA Know and When Did They Know It?" Among the speakers will be NHTSA Administrator David Strickland and GM CEO Dan Akerson. Conveniently the NHTSA closed their investigation last week and released a document about the fire incident answering questions about the timing of the investigation into the Chevy Volt fire.

The crash testing of interest came as part of NHTSA's New Car Assessment Program (NCAP) under the agencies policy of testing vehicles with "new technology". For 2011 they were especially interested in electrified vehicles with lithium-ion batteries, like the Chevy Volt. The program consists of frontal, side, electrical isolation and rollover tests. The post-crash rollover test is intended to test for leakage of electrolyte from battery powered vehicles, or fuel spillage from gasoline or diesel vehicles.

Between April 20 and May 12, 2011, Chevy Volt crash testing occurred at the site of an NHTSA contractor, MGA Research. Based on its performance in that test the NHTSA awarded the five-star NCAP crashworthiness rating. After the crash test the Volt was moved to a storage lot. This much we knew already, it's starting from this point that the NHTSA report begins to fill in details in the timeline.

The NHTSA report lists four crash tests in the April 20-May 12 period. Three were side impact tests, two of which caused intrusion into the battery pack, and it was the test on May 12 which caused battery coolant leakage.


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One inconsistency it that the Volt's post-crash protocol calls for the discharge of the batteries (through a load, I'm sure), but the *experts* at NHTSA, who should know how to deal with crashed vehicles, didn't bother. Why were they so remiss? And the article provokes some questions. If "the coolant to be conductive at high voltages", what are they using as coolant? And what exactly do they mean by "conductive"? I would suppose regular Ethylene Glycol - Water, which is conductive in the ionic sense, but more conductive at high voltages? What do they mean by that? And how conductive? `~- Nehmo
That post-crash-drain-the-batteries protocol was developed following the forensic study of the crashed Volt. "Conductive" means conducts electricity, and that phrase came from the NHTSA report from their forensic study.
Incorrect. The protocol of de-powering the batteries after battery damage or the possibility of it was there before the crash. search: chevy-volt-catches-fire-weeks-after-crash-feds-probe/1 'Volt, spokesman Greg Martin said. "Had those safety protocols been followed for this test, this incident would not have happened," he said, adding that this is the only crashed Volt ever to catch fire.' and search: chevy-volt-fire-post-crash-test-protocol-slip 'The protocol not followed by federal testers, according to GM's spokesman was not "de-energizing the battery after the crash test." ' Moreover, in a a crash in the real world, GM’s Onstar system would report the crash and provides enough data to indicate if the battery was damaged. GM would then have the opportunity to follow up to see if the protocols were implemented. And of course I know "conductive" means the ability to conduct. But conduction of a material is an intrinsic value that typically doesn't change with voltage. Please re-read my post. There's no point in repeating myself. However, since I wrote that, I discovered what they really meant was that the liquid *when crystallized* (not when higher voltages are applied) becomes significantly more conductive. This is understandable, and it answers the question I said the words of the article provoked. Finally, if you want to cite something, then link to it (you should be able to post links here) and quote exactly you are referring to. `~- Nehmo
Where did the spark come from anyway? My guess is that the NHTSA did depower the vehicle right after testing. This seems like normal protocol. Thus, a depowering event causing a spark a week, 2 wks, or 3wks later could not have caused the spark that ignited the gas. Well take a look at your gas grill, more specifically the igniter. Within the typical house hold gas grill igniter exist a very powerful and exotic material. Yes, most have a material called PZT (Lead Zirconate Titanate) which is a very well-known and well-used piezoelectric material. Point being, LG Chem LTD also has this material in its batteries (just review their patents)! If it is not a short circuit created by the vehicle depowering causing the spark then what could it have been. Well, GM is standing by their statement that there was an internal short caused by depowering event even if it does not make sense. They are basically saying that the NHTSA does not know how to conduct a test. The same safety feature/material (i.e. inorganic piezoelectric particles) that LG Chem LTD puts into their Chevy Volt batteries, that supposedly prevents fires, is now turning around and biting them, and putting A123 System’s in front of the pack at the same time. In fact, this is the same material which caused GM to switch to A123 Systems for its new GM Spark EV (yeah me too, the fire is from a Spark and that's what they name their next, and best, micro-HeV??). This is the same reason why LG Chem LTD, after going back to the drawing board, filed another patent, currently in EU application phase. This patent application is not of the innovative type, it is of the damage control type. LG had to find a way to implement this piezoelectric effect (i.e. their inorganic piezoelectric particles), maintaining the same performance gains, keep with their supposed safety feature and win the next major HeV battery supply contract. At current, there is a very large and far reaching difference between LG Chem LTD and A123 System’s Lithium batteries and older Lithium batteries of just 4 or so years ago. LG Chem was the first out of the gate, and A123 System’s learned from their mistakes. A much safer implementation of the piezoelectric effect is possible without giving up the performance and high-rate cyclic performance. It’s a learning process and we will see GM jump horses many times in the future. These Lithium battery manufacturers are at war, there will be many step type increases in performance over the next 5 or so years. The resultant batteries will be of a new age and they will meet all our needs. The NHTSA should take a closer look and conduct a material analysis of LG Chem’s batteries and if these piezoelectric particles exist, and they are not electrically isolated from the chemical reaction process within the cell, they should consider that this material may have been the ignition source. This type of material can and should be used to make our batteries perform better and last longer and they can be utilized in a completely safe manner. ‘Call me maybe’ 413-579-7108 Piezoelectricity means that if you deform this material it will generate a voltage, and if you apply a voltage to it it will deform. So, in LG Chem's battery they put this material in to prevent a short-circuit upon an impact. The idea is the piezoelectric material will create voltage at impact and essentailly opposes the short circuit potential