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Stuart21
User Rank
Gold
Re: No doubt, debate
Stuart21   4/16/2012 12:37:26 PM
NO RATINGS
Not at all.

There are many variables such as Ph, temperature (I anticipate room temp), Salinity, turbidity (Clear) etc etc. So best to assume a fairly common standard - fresh water is most common. This could be changed to a certain salinity in 5 or 10 years or so - depending upon how the original design rule 'performs'.

The length of time would be sufficient to ensure manufacturers protected against electrolysis - i.e. not destroying computer and instruments. A short dunking would not test this. All materials should survive 24 hrs in fresh water, tho dissaembly, cleaning, drying etc, new oils, filters etc may be required.

With the extreme weather we have been having, insurance cos have been enjoying 'windfall losses' due to poor design & test procedure of manufacturers, and poor driving choices of drivers.

Yes, I have put quite a bit of thought into this proposal.

GlennA
User Rank
Gold
Re: No doubt, debate
GlennA   4/16/2012 11:23:29 AM
NO RATINGS
By what reasoning did you decide that a 24 hour submersion in fresh water is a vaild design constraint ?

Or was this tongue-in-cheek ?

Stuart21
User Rank
Gold
Re: No doubt, debate
Stuart21   4/16/2012 11:09:49 AM
NO RATINGS
& I want to know what happens when an EV car gets dunked - fresh water or salt water. No discussion of this AFAIK. There is potential (pun intended) for electrocution.

I have proposed a new Australian Design Rule that - any - new car (EV too) must survive a 24 hour dunking in fresh water without having to be written off. Sure change oils minor repairs but insurance companies should not be stuck with poor design choices of manufacturer.

DanielJoseph
User Rank
Gold
Re: More dangers
DanielJoseph   4/16/2012 11:07:12 AM
NO RATINGS
I am having a tough time with the sensationalism going on here by engineers and others.  The battery is experimental - they were trying to get it to fail - it failed which was the whole point of the test.  The test would have been a failure if they did not discover the failure point.  Was there some other issue with the test chamber that caused an unexpected buildup of gases - can't say, but that is what the story should be about - and of course those affected by the aftermath.  Also, worrying about mechanic working on an electrified car is almost as mis-informed.  Cars have been electrified with enough power to kill someone for quite a while.  My point is mechanics are trained for these things.  The new mechanics will be trained with the same training that electricians receive who work on high voltage systems.  Just to be clear, every Volt runs on the same inverter technology that has existed in factories for years.  I am not being trite here, it is simply something to be learned not to be feared.  So please, stop with the worry wart stuff! 

ChasChas
User Rank
Platinum
never say never
ChasChas   4/16/2012 11:00:28 AM
NO RATINGS
 

I personally experienced a golf cart battery explosion - said to be in good working order - lead acid of course.

We do the best we can, but "never say never."

 

gearhyde
User Rank
Iron
Re: More dangers
gearhyde   4/16/2012 10:55:41 AM
NO RATINGS
Personally, I think the EV battery dangers are being way overblown.  That's one of the problems with today's social media.  Have you ever heard of the dangers of the common 12 Vdc or 24 Vdc battery exploding or causing fires?  I doubt it and yet it has happened. 
Back when I was still an automotive mechanic, I was checking over the electrical/charging system of a vehicle that was brought with a hard-to-start problem.  The charging and starting systems all checked out which left the battery.  When I did a load test on it, the top of the battery blew off.  I was fortunate that I was wearing glasses, otherwise I would have had acid in my eyes.  As it was, I had to have stitches where the battery top struck my face. 
My point is this: Everyday we all are in close proximity of items that can hurt us.  Our laptops and electronic devices all have lithium ion batteries.  They can can explode as well.  As one poster pointed out, our cars all have tens of gallons of gas and yet we don't rail about the dangers of that. 

Tim
User Rank
Platinum
Re: More dangers
Tim   4/15/2012 6:00:08 PM
NO RATINGS
Glad to hear that my battery will not explode, but I agree on the voltage danger.  First responders had significant concern with the latent voltage of the lithium ion battery stack on EV's when they were introduced.  It would be a terrible thing if they needed to use the jaws of life to peel the car away from you after an accident only to be hit with high voltage from the car during the rescue. 

Jack Rupert, PE
User Rank
Platinum
Re: More dangers
Jack Rupert, PE   4/15/2012 3:04:04 PM
NO RATINGS
I agree Warren.  This incident happenened during a factory test.  I'm sure there could be other "extreme" tests done on gasoline powered cars that would make them go boom as well (Ford Pinto anyone?).  As you mentioned, voltage is a much bigger issue.  I used to work in an industry that due to it's nature needed to be extremely safety aware and pretty much everyone was well trained in their jobs.  No back-yard mechanics there.  You needed to be an card-carrying electrician to work on anything over 24VDC.  I worry about somebody who knows just enough to be dangerous trying to fix one of these in his driveway.

Scott Orlosky
User Rank
Platinum
Re: No doubt, debate
Scott Orlosky   4/14/2012 7:48:31 PM
NO RATINGS
Unfortunately, people are notoriously bad at assessing risk, even when given accurate information.  Stoking fear by sensationalizing an event doesn't help the situation.  To be fair, driving a car is probably the single most dangerous part of anybody's day.  Yet, despite the 40,000 deaths a year from this activity (in the U.S.) you don't hear any public outcry.

warren@fourward.com
User Rank
Platinum
More dangers
warren@fourward.com   4/14/2012 3:33:59 PM
NO RATINGS


I am not as worried about the exploding battery issue as I am with the dangers involved to the poor mechanic who has to work on these things.  The high voltage can kill!  Plus, the computer goes through a systems check periodically and activates, amongst many other things, the brakes.  If you are working on the brakes at the time, you might just lose a finger!  Mechanic friends of mine are scared of the electric cars.  You can't always get a factory tech, so the small-town mechanic might be the highest risk group of all- not Alaskan crab fisherman dangerous- but significant nonetheless.
 


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