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Old 03-09-2008, 09:49 PM   #16
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I guess it's like many have said, sloppy soldering covering vents, aggressive charging profiles . . . user error . . .

I guess the powers that be are working on a 4 cell 1/12 th scale LiPo fitment for the pan cars . . . that would be nice . . .
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Old 03-09-2008, 11:44 PM   #17
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With the dramatic increase in batteries, I started when 1700s were exotic, and the reduced weight of lipos, could the answer for 4 cell possibly be 3.7 volts?
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Old 03-10-2008, 02:11 AM   #18
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these explosions are huge!

Ask my freind with the car mising a place to put the batteries

He was peaking his battery before a race in his car.

And then he looked away and hey presto a chassis modification with a large effect
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Old 03-10-2008, 03:34 AM   #19
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whats with the 50-55 degrees for charging the cells

mine are around 80-85

is that bad
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Old 03-10-2008, 04:48 AM   #20
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50-55 deg/c is extreme.
my chargers are set at 47deg/c but its not fool proof since you only measuring 1 cell to 2 cells max out of a pack of 4/5/6

Freind who owns a Local hobby shop just called me a ferw mins ago.
They were charging a IB4200 pack for a demo car when it started venting and one of the staff ran out of the shop with it and put it on the ground in a parking bay. He says 20 seconds later it exploded.
A end cell blew up.
No one was hurt but they and a few customers as well as bypassers where shocked by the explosion and how loud it was.
Cell casing was found about 20-25 meters away !!!

Google earth pic of parking lot to give you an idea of distance below.
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Old 03-11-2008, 07:36 AM   #21
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Picked up the battery pack to take a pic of it.

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Old 03-11-2008, 07:42 AM   #22
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Influential ROAR director had a nimh blow up on them a couple weeks ago and got slightly hurt by it. I wonder if ROAR will address this now?
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Old 03-12-2008, 04:49 AM   #23
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So, from reading this thread, one can assume that nimh is safer than lipo.

I have an MRC SuperBrain 960 charger, and I was thinking of picking up some nimh packs (3000 or 3300). Is this charger okay to use? It says that it charges nicd and nimh with delta peak and all of that, but it does not have an external temp sensor.

I have never experienced a battery venting before it explodes. What is the sound of a battery venting?

Thank you for the good info!!
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Old 03-12-2008, 09:51 AM   #24
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Quote:
Originally Posted by Zagar View Post
So, from reading this thread, one can assume that nimh is safer than lipo.

I have an MRC SuperBrain 960 charger, and I was thinking of picking up some nimh packs (3000 or 3300). Is this charger okay to use? It says that it charges nicd and nimh with delta peak and all of that, but it does not have an external temp sensor.

I have never experienced a battery venting before it explodes. What is the sound of a battery venting?

Thank you for the good info!!
batteries are as safe as the person using them...

anyway a venting cell sounds like air escaping from a punctured bike tyre, or maybe some kind of killer snake. anyway, you'll know it when you hear it.
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Old 03-12-2008, 10:18 AM   #25
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Quote:
Originally Posted by joe of loath View Post
batteries are as safe as the person using them...
Im not sure I completely agree with that. I dont believe all the people that had IB4200s blow up (but had never had a battery blow up before) were being any less safe then they had in the past. People definately play a HUGE role in battery safety. But the mfg does need to put in some safeguards as well.
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Old 03-12-2008, 11:00 AM   #26
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Lots
of

Ka ! Booms !


and

Still no safeguards for Nk-ML and every ones protection...
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Old 03-12-2008, 11:11 AM   #27
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Interesting.... I was reading in another thread about Lipos by linger, and I am seriously thinking of just going with lipos now. Not to mention that the run times are very appealing. No more 5-8 minutes, huh?
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