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        Can Triton temp. sensor prevent Lipo fires??

#1 duganderson Sep 28, 2003 10:42 PM

Can Triton temp. sensor prevent Lipo fires??
 
I'm considering getting a couple of the new 2 cell Kokam 1500 Lipo batteries but am considered about everything I've heard about Lipo fires.

Does the Triton temperature sensor help prevent fires, or could a fire start before the outside of the pack gets too hot??? The sensor is supposed to shut off the charger if the sensor determines the battery is too hot.

Any other tips for fire prevention?

Thanks, Doug

#2 frederm2002 Sep 29, 2003 03:25 AM

I think that is a great question and suprised there is no response.

Surely someone that did some extreme testing would have an opinion on this.

It would seem to me that problems caused by over charging would first result in heat in the cell. but I do not know this first hand.

if that heat, as you suspect, is higher then the cutoff limit then the triton would shut off.

Lets hope we get some more info on this as I am also very interested in knowing. well worth the $15-$20.00 for the probe if it would.

Mike

#3 RD Blakeslee Sep 29, 2003 07:46 AM

Mike, maybe nobody knows. Personally, I wouldn't rely on "automatic" temp. sensing and charger cutoff.

When I used a MAHA Plus charger some months ago, the temp. sensor did not cut off even though some NiMH cells I was charging got too hot, IMO. I can't say how sensitive the Triton's sensor is - I've never used it.

There have been reports of apparently cool LiPo packs "puffing".

So far as I know, there haven't been any reports of apparently cool packs catching fire.

- RD

#4 STL.SF Sep 29, 2003 08:00 AM

I could imagine that if the failure mode of the Lipo cells is that they "puff" prior to catching on fire then the temperature probe may never see a hot cell. The gas inside the puffed cell would tend to insulate the outside of the cell.

Does the cell heat prior to "puffing"??? Does anyone know enough about these failure modes?

STL

#5 STL.SF Sep 29, 2003 08:05 AM

Added Thought
 
Do the Lipo cells puff before catching fire?

If so, then maybe a fixture that included a microswitch to cutoff charging if the cell expanded would be a means of increasing safety. This could be rather inexpensive to add to existing chargers.

STL

#6 dmccoach Sep 29, 2003 11:10 AM

Guys, I have been thinking along the same lines, and we need to urge the designers to come up with a solution...

The cells definately warm up during overcharge, then they puff, then they get hotter, then they burst and flame... I know I have overcharged one, and caught it just as it "puffed"... It was about 120F at that point.

So I envision a casing that the cells are placed into either at MFG, or Post-MFG by a value-added reseller.

The casing (I have no idea what material) would have thermal AND pressure-sensitive circuitry that could cut the charge voltage to the cells... This would not be the "normal" cut-off for charging, but a circuit-breaker system...

I imaging the charging would have to take place "through" this casing-circuitry.

I wish I was an engineer, I would set to work on it.

Thanks, Dan

#7 Dylwad Sep 30, 2003 12:01 AM

Ive tested the temp probe on the triton. even sometimes by accident when i set the cut off temp 10 degrees above ambient in my house to find the charger shut off on me the next day charging outdoors. the temp probe works, and i believe it will keep a lipo from exploding, However, i still wouldnt leave the charger unattended while charging......ever


Dylan

#8 DNA Sep 30, 2003 01:07 AM

http://www.rcgroups.com/forums/showt...402#post806402

#9 chuck75 Mar 04, 2014 01:41 PM

The potential problem with Lipos is that they can get hot between the inner cells, and still be just a bit warm on the outside.

#10 Zeeb Mar 04, 2014 02:19 PM

Did not notice it was a 10 year old thread....

#11 mrforsyth Mar 04, 2014 02:20 PM

Bumping a 10+ year old thread might be a record!

I rather suspect that the OP has long moved on from his Triton by now...

#12 Zeeb Mar 04, 2014 02:21 PM

Quote:

Originally Posted by mrforsyth (Post 27688800)
Bumping a 10+ year old thread might be a record!

Yep, you'd think I'd learn to look at more than the last post date especially when the subject matter is that old..... lol :o

#13 chuck75 Jun 23, 2014 01:57 AM

It's not so much the age of the post, or the mfr of the charger. It has more to do with the usefulness of a temperature sensor. I have a couple of sensors, and due to reasonable charging currents, have never had them show anything significant. Use with NiCads and NMIH batteries can be a totally different story.

#14 hoppy Jun 23, 2014 08:14 AM

A thickness change trigger wold be much more effective. Lipos do expand slightly on charging but nothing in comparison to the expansion when they are being overcharged.

#15 _nicos Aug 25, 2014 10:53 PM

Well, 10 years old or not, I'm now interested in this thread on account of a fire I had at my place last weekend.

I was charging 6x 2s 300mah on a parallel harness... I don't believe they were overcharged and were in good physical shape... it was nasty and could have been SOOOOO much worse. It started with one, then all hell broke loose right in front of my face. Another 5 minutes more and it would have been time to call emergency services.

So I'm into getting a temperature probe that will work with one of these chargers... perhaps this one?


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