HOME  |  NEWS  |  BLOGS  |  MESSAGES  |  FEATURES  |  VIDEOS  |  WEBINARS  |  INDUSTRIES  |  FOCUS ON FUNDAMENTALS
  |  REGISTER  |  LOGIN  |  HELP
Comments
View Comments: Newest First|Oldest First|Threaded View
<<  <  Page 2/3  >  >>
Elizabeth M
User Rank
Blogger
Re: A Good Vent
Elizabeth M   8/7/2013 7:58:38 AM
NO RATINGS
That sounds like good advice, tekochip--in fact, it sounds a bit like a no brainer! But I guess an experienced engineer might get lazy sometimes with safety? I'm personally not an engineer and don't do a lot of work in a lab situation, so I wouldn't know, but I guess if you do something every day you might think you can slack a bit with the safety precautions. It's good to remind people not to! Glad you came out of the accident OK.

MIROX
User Rank
Platinum
Packaging
MIROX   8/7/2013 4:57:34 AM
NO RATINGS
I think it is great that someone be it UL or who ever can come up with some safety test, not just for Li Battery but for ANY battery.

From experience I also think that the entire "package" needs to be evaluated and tested, as for example I have seen more than one Golf Cart where the entire vehicle burned down, just because one battery wire was having too high a resistance and caused enough heat to not just melt a Lead-alloy post but ignite what ever was next to it, which in turn burned down the entire vehicle.

Other example may be the few Fisker cars, that burned for what ever reason, but one of them was apparently short in "cooling fan motor" that burned off entire 1/2 of front end of the car.

So NOT having easily flammable materials next to "potential" ignition source, be it extreme heat or spark, is also somthing about which engineers need to think about and design in appropriate safety.

I.e. if battery fails, for what ever reason, the device, be it computer or a car, should not be a total loss as a result !

D Hambley
User Rank
Silver
Is UL's indenting test valid?
D Hambley   8/6/2013 5:58:27 PM
NO RATINGS
I really think UL has missed the point on this one. One of the mysteries concerning L-ion cell failures is why L-ion cells short in the first place! This "indenting test" which forces a short to make it fail will NOT test to see if a cell has been designed and built to avoid shorts. All it does is to test whether a cell overheats AFTER this mysterious short. It's like UL is saying, "it's OK to have a cell which mysteriously shorts. After a forced short though, we want to ensure that it doesn't overheat." I say go after the cause, not the result.

tekochip
User Rank
Platinum
Re: A Good Vent
tekochip   8/6/2013 2:26:16 PM
Always wear your safety glasses in the lab.

 

I washed my eyes out first and just a few minor burns on my neck and face.

Elizabeth M
User Rank
Blogger
Re: A Good Vent
Elizabeth M   8/6/2013 1:53:57 PM
NO RATINGS
Oh my gosh, that sounds horrible. I hope you are OK. I take it you have learned alot from this situation and I guess having some kind of guidelines or test to prevent such a thing in the future is something you would welcome. Take care!

tekochip
User Rank
Platinum
Re: A Good Vent
tekochip   8/6/2013 1:51:23 PM
NO RATINGS
I made a careless mistake and paid for in seconds.  The cell energetically disassembled without the slightest hint that it was aggravated with me.  As if the chemical burns weren't bad enough, the freed lithium also ignited, so I had to figure out if I wanted to wash my eyes out first or put out the little fires scattered across my workbench.


Elizabeth M
User Rank
Blogger
Re: Suprised UL is not already involved
Elizabeth M   8/6/2013 1:34:02 PM
NO RATINGS
I know what you mean, Lou, it seems like there has to be an incident with serious consequences before companies improve certain aspects of their products or, in the case of the airline industry, airplanes. But in all fairness, perhaps they weren't aware that there was potential for such problems in the first place. This is where more careful and attentive design with anything, especially lithium-ion batteries, must come into play.

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.

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.

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!

<<  <  Page 2/3  >  >>


Partner Zone
Latest Analysis
The engineers and inventors of the post WWII period turned their attention to advancements in electronics, communication, and entertainment. Breakthrough inventions range from LEGOs and computer gaming to the integrated circuit and Ethernet -- a range of advancements that have little in common except they changed our lives.
The age of touch could soon come to an end. From smartphones and smartwatches, to home devices, to in-car infotainment systems, touch is no longer the primary user interface. Technology market leaders are driving a migration from touch to voice as a user interface.
Soft starter technology has become a way to mitigate startup stressors by moderating a motor’s voltage supply during the machine start-up phase, slowly ramping it up and effectively adjusting the machine’s load behavior to protect mechanical components.
A new report from the National Institute of Standards and Technology (NIST) makes a start on developing control schemes, process measurements, and modeling and simulation methods for powder bed fusion additive manufacturing.
If you’re developing a product with lots of sensors and no access to the power grid, then you’ll want to take note of a Design News Continuing Education Center class, “Designing Low Power Systems Using Battery and Energy Harvesting Energy Sources."
More:Blogs|News
Design News Webinar Series
3/31/2015 11:00 a.m. California / 2:00 p.m. New York
2/25/2015 11:00 a.m. California / 2:00 p.m. New York
12/11/2014 8:00 a.m. California / 11:00 a.m. New York
5/7/2015 11:00 a.m. California / 2:00 p.m. New York
Quick Poll
The Continuing Education Center offers engineers an entirely new way to get the education they need to formulate next-generation solutions.
May 4 - 8, Designing Low Power Systems using Battery and Energy Harvesting Energy Sources
SEMESTERS: 1  |  2  |  3  |  4  |  5  |  6 |  7


Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.
Last Archived Class
Sponsored by Proto Labs
Learn More   |   Login   |   Archived Classes
Twitter Feed
Design News Twitter Feed
Like Us on Facebook

Sponsored Content

Technology Marketplace

Copyright © 2015 UBM Canon, A UBM company, All rights reserved. Privacy Policy | Terms of Service