Thread Tools
Apr 21, 2005, 08:31 PM
My hangar is,... "almost" full
No Step's Avatar

My fire, my fault


Geez, I hate admitting this, but I do so only in hope of inspiring caution in someone else that may be getting lazy in the way thay handle Lipos.

I've been using Lipos for about a year and a half. I always put them in a metal box to charge, both at the field and at home. I considered myself overcautious when charging. However, , recently, I got careless. I was setting up a new plane for maiden flight while charging a 3S 1320 TP pack. I grabbed the lipo pack and noticed a rubberband around it. Damn! did that mean it was charged or discharged? I forgot. I know that's stupid. But the fact is I didn't know if it needed charging or not. I should have just flew it as it was. I hadn't flowen that pack (or plane) for quite a while. I wanted to fly it before putting the maiden flight on my new bird - https://www.rcgroups.com/forums/showthread.php?t=259657 . So I got absent minded and put it on the charger, I slapped it on the Astro 109 charger, dialed in 1.3 A charge rate, and walked away to more important things... my new airplane. Big mistake again. I should have confirmed that it recognized it as a 3S pack at the very very least. Next mistake, I had it sitting on the front of the engine compartment next to the car battery (never had a problem before, I got careless, took a shortcut, didn't use my metal box, besides, I had more pressing issues,... my new airplane.
Well, setting up the new plane, I heard the charger beep. It was 10 feet away. Yeah, yeah, yeah,... I'm busy, I'll leave it for now, I've got more important things to do right now. Well, about 5-10 minutes later it blew! Sounded like popping a paper bag. Fire! The size of a computer CPU.... 3-4 seconds to get to the car (van). Kicked it off the car engine area, it hung there a second or two, and then onto the ground. Fire out. It scourched the grill a little.

I was super lucky and I also am super happy it happened. It could have been much worse given different conditions (like if I was flying and couldn't get to the car immediately). Now I will be more careful (like before) and not get casual in how I handle these Lipos.

In hindsight, what I >think< happened is the pack was in fact already charged fully, and the charger sensed a low 4S rather than a fully charged 3S. Whatever the reason, it happened. I don't want it to happen again. I should have confirmed C1, but didn't,... should have put it in a metal box but didn't, etc, etc.
Please don't slam me for not following instuctions. I got casual and I shouldn't have, I admit that. I had an incident, I came out of it good. I learned from it. I need to review my safty & charging proceedures. I admit to this incident >>only<< to help others prevent it from happening to others, cuz it will. Just when you let your guard down they'll bite you. Be careful, don't take shortcuts.

Btw, the maiden flight on the new plane went extremely well, glad it wasn't it's 4S2p pack that burned.

Be careful

Fred G.
Last edited by No Step; Apr 21, 2005 at 08:37 PM.
Sign up now
to remove ads between posts
Apr 21, 2005, 08:32 PM
My hangar is,... "almost" full
No Step's Avatar
Ugh, sorry for the large picture ( new software, I resized it wrong). I'll try to fix it.
Apr 21, 2005, 08:35 PM
Got H2? Fuel Cell R/C Car
Keith43221's Avatar
Ouch baby, Good to hear nobody go hurt. But man, what is the wife going to say about the car? Be safe and have fun!
Apr 21, 2005, 08:40 PM
My hangar is,... "almost" full
No Step's Avatar
She hasn't got home yet. It's mostly soot, some bubbleing of the paint and plastic lense cover. You can see where I rubbed some of the soot off. Glad it's not a new car too,.... 100K+ miles. Picture fixed.
Apr 21, 2005, 08:42 PM
Southern Pride
everydayflyer's Avatar
Looks more like a stich pack than a LiPoly. I know a few who charge under hood ,hope they see this.

Charles
Apr 21, 2005, 08:42 PM
Got H2? Fuel Cell R/C Car
Keith43221's Avatar
Wait just what happened. It looks like 2 exposion marks? different cells maybe?
Apr 21, 2005, 08:55 PM
My hangar is,... "almost" full
No Step's Avatar
That's where I wipped it off in the middle.

Not a stick pack, The picture shows a 1950 NiMh pack being charged on a Astro 110. I meant to just show the damagae to the car,... I mean van.
Apr 21, 2005, 09:10 PM
Registered User
ebill3's Avatar
Thanks for posting. I know a guy who charges LiPos in the back of his van on the way to the field. I'll make sure he sees this.

Bill
Apr 21, 2005, 09:58 PM
Registered User
Fred, your openness and honesty is greatly appreciated. You are another confirmation of a recent pattern on this forum where knowledgeable, safety-conscious, careful people who've been using LiPos safely for a year or more let down their guard and got bitten.

What you did is nothing that all of the rest of us haven't done more than once. It's a natural tendency to let down your guard after long use of any device without a single problem. This happens to people with firearms, too, and you know that's a heck of a lot more serious. Thing is, thanks to statistics, most people get away with it. Only a small percentage of LiPo users end up suffering as you did because these kinds of accidents are statistically uncommon. Random luck of the draw is such that it's not predictable who will get away with letting down their guard and who won't.

The great thing about sharing an experience like this here is that it is a clear message to all the other knowledgeable, safety-conscious, careful people that the only reliable way to avoid becoming a victim of statistics is to keep your guard up. Always. The reason you didn't have problems previously is not because the product is inherently safe, but because you were being inherently cautious.
Apr 21, 2005, 10:29 PM
Registered User
I'd be really dissapointed with that Astro charger! Is bad auto detection of cell count a common event?
Apr 21, 2005, 10:36 PM
Registered User
Fred;

Sorry to hear about the damage but I'm glad it wasn't any worse. Although lipos are generally safer now than when they first came out, there is still the potential for fire as you have found out. Thanks to your honesty I will reassess my safety precautions for my lipos. I hope others will do the same so that reports like yours become less common in the future.



Jerry
Apr 22, 2005, 12:02 AM
Registered User
Quote:
Originally Posted by Foamee
I'd be really dissapointed with that Astro charger! Is bad auto detection of cell count a common event?
It seems to be so with this charger. I wish Astro Flight would implement a manual control for cell count instead of auto detection.
Apr 22, 2005, 01:27 AM
Permanently Banned
Larry3215's Avatar
Actually its not a common problem with the Astro.

My guess is a bad conector.

I noticed the other day that one of my Astro 109's seemed to be under charging packs.

After much testing, charging, discharging and wasted time I noticed that 109 was reading battery voltage much higher than the other one at the same charge rate with the same battery.

Did some more testing and looking and found one of my conectors was in bad shape. One of my power poles had slipped back in the houseing and was not making good contact. The tip of the metal insert was pitted as well.

Replaced the conector and both agree 100% again.

That bad conector was causing the charger to read 1.2 volts hi on a 4S pack at .85 amps charge rate.

It might be hard to tell after the fire - but I would check the conectors. It could also have been one of the conectors on the pack as well. Charger leads may have been fine.

Larry

P.S. - I charge under my hood in a brinks box also
Apr 22, 2005, 01:58 AM
Registered User
ebill3's Avatar
Quote:
Originally Posted by Foamee
I'd be really dissapointed with that Astro charger! Is bad auto detection of cell count a common event?
My comment is not meant to "pile on", as Fred freely admits that he took short cuts.

The 109 instructions are very clear concerning start-up and verifying cell count, and strongly cautions that charging a charged pack could result in an erroneous cell count.

My guess is that the pack was already charged and Fred did not verify cell count.

Bill
Last edited by ebill3; Apr 22, 2005 at 02:06 AM.
Apr 22, 2005, 05:26 AM
Registered User
Quote:
Originally Posted by ebill3
My comment is not meant to "pile on", as Fred freely admits that he took short cuts.

The 109 instructions are very clear concerning start-up and verifying cell count, and strongly cautions that charging a charged pack could result in an erroneous cell count.

My guess is that the pack was already charged and Fred did not verify cell count.

Bill
First, Fred, I'm glad the damage wasn't too bad, it could have been a lot worse as you say.

Second, I wish chargers that say they are lipo compatible were also lipo safe! Instructions can be mis-read, or ignored!

If the Astro 109 (or any charger for that matter) is capable of mis-reading a full 3s as an empty 4s it SHOULD NOT START until the user confirms. sounds to me like the Astro asked for confirmation with beeps?? and then went ahead anyway and charged (fried) the pack.

FWIW my Apache2500 absolutly refuses to charge a 100% full 3s (12.63v) on the 4s setting. I tried it in a controlled experiment.


Stuart


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Lipoly Fire - my fault entirely - some lessons Ben Lanterman Batteries and Chargers 18 May 25, 2005 02:04 PM
My Fault LeeU 3D Flying 1 Feb 10, 2004 09:33 PM
Rant Second eolo stripped gear! (my fault) EP heli freak! Electric Heli Talk 8 Jan 20, 2004 09:34 AM
Phionex 10,red light,no worky,my fault? Matthew Cotten Castle Creations 18 Jan 06, 2004 09:08 AM
Universe altered, my fault tekochip Batteries and Chargers 14 Nov 02, 2002 12:13 PM