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tekochip
User Rank
Platinum
A Good Vent
tekochip   8/5/2013 9:03:06 AM
Having recently been injured by a lithium battery explosion, I think a good vent
is important in the cell.  These cells build up pressure so rapidly that there
needs to be a means of safely releasing the pressure safely, not explosively.

naperlou
User Rank
Blogger
Suprised UL is not already involved
naperlou   8/5/2013 9:15:35 AM
Chuvk, frankly, I am suprised that UL has not been involved in lithium-ion battery certification before now.  It seems that we have to have problems before it is decided that it would be good to have a third party certification.  With laptop batteries it took fire in some Apple laptops to get this going.  With cars and planes, again it seems that we needed fires before this was done.  Considering that the volatility of the chemistry was known at the start, this seems short sighted.

Gorski
User Rank
Platinum
lithium-ion battrey fires
Gorski   8/5/2013 3:50:37 PM
Since there have been a spate of lithium-ion battery fires lately, I was surprised that UL is just now geting into the act. The overheating must have shown up before. Every battry made until now has not been perfect. Who was hiding this overheating problem, and why?

Gorski
User Rank
Platinum
lithium-ion battrey fires
Gorski   8/5/2013 3:50:47 PM
NO RATINGS
Since there have been a spate of lithium-ion battery fires lately, I was surprised that UL is just now geting into the act. The overheating must have shown up before. Every battry made until now has not been perfect. Who was hiding this overheating problem, and why?

Charles Murray
User Rank
Blogger
Re: Suprised UL is not already involved
Charles Murray   8/5/2013 6:16:24 PM
NO RATINGS
Naperlou, UL previously had standards covering battery packs for portable applications using all kinds of cell chemistries, including lithium-ion. What's new here is that UL is creating an internal short circuit test method for inclusion in the lithium battery safety standardc UL 1642. This addresses the problem that has been written about a lot -- internal short circuits related to separator failure.  

Charles Murray
User Rank
Blogger
Re: lithium-ion battrey fires
Charles Murray   8/5/2013 6:23:48 PM
NO RATINGS
Up to now, the problem has been one of underestimating the potential overheating issues involving lithium-ion, Gorksi. This is a trap that has snared a few engineers. Better testing methods, particularly those that consider internal shorts, should help. The question is how many of the makers of big li-ion battery packs -- like those used in autos and aircraft -- will take advantage of this.  

Jim_E
User Rank
Platinum
I'm trying to avoid them....
Jim_E   8/6/2013 9:22:12 AM
While our cell phones, laptops and tables have them, I'm trying to avoid Lithium-Ion batteries elsewhere.  I'm a bit of a LED flashlight junkie, but I've avoided any that take the more powerful 18650 and 14500 Lithium-Ion batteries after reading about over-charging and over-discharging fires!

I'd love to have the extra power, but it's not worth the risk for me, especially if I can't just charge the things unattended.  Maybe I just need to build a concrete charging hood and place it on my granite countertops....

I'll just stick to AA and AAA for now until something better comes along that doesn't have the propensity to explode and catch fire.

Dr Bob
User Rank
Silver
Re: A Good Vent
Dr Bob   8/6/2013 9:25:16 AM
Many years (25+) ago I had it on good authority that Lithium batteries do not explode (ever). They rupture, sometimes with extreme prejudice, but never ever explode!

Jim S
User Rank
Gold
Re: A Good Vent
Jim S   8/6/2013 10:04:34 AM
NO RATINGS
Extreme Prejudice, that's a good one. In other words a violent exothermic chemical reaction at an extremeny high rate. (Explosion for most of us). During the early years of developing Lithium batterys for downhole use a company I know of had an oven controller fail over the weekend and workers arrived monday morning to find the chamber destroyed, as well as the brick wall behind it. Luckily it contained the fire and did't set the lab on fire. we were always very careful after that to make sure we didn't short cells out.

Elizabeth M
User Rank
Blogger
Re: A Good Vent
Elizabeth M   8/6/2013 1:23:04 PM
NO RATINGS
Wow, that's terrible that you were injured, tekochip, what happened? I hope this test prevents these things from happening in the future with lithium-ion batteries.

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