Umm... Why did my gun light on fire?

[Alpha]

So I'm cleaning my gun today, the night before a tourney... Just tightening up some loose screws.

I pop my battery into my charger.. I charged it earlier today but had to remove it before it was fully charged.. Just to show a friend my gun.

Anyways, I continue cleaning my gun, with my battery 'charging'. Or at least I thought it was. The light said it was green... I shrugged and pushed on teh battery thinking maybe it wasn't makign a connection with teh electrodes... NOpe...

So I took it off the charger and set it aside.

One E-mag cleaned later, I begin to smell something.. IT kinda reminded me of the arts and crafts box in kindergarden.. And its weird ebcuase thats what I actually thought of...

I see grease all over my hands, and attribute it to that.

I finish assembling the rest of the gun, when I get the feeling its something burning. I look around. Nothing on fire. I look at the charger and unplug it. I check the polarity... Correct. I check the voltage... Set at 12v.. The label says 10-15vDC input.

I look closer.

Where it had been resting on a pen, it melted the plastic. I noticed it pluming smoke after I remove it.

Now, heres my issue:

The polarity was correct. I know this becuase the green light was on (and I double checked the tip attachment). I know there was only 12v going into it, because first of all the power adapter is sort of new, and its worked for the past 2 months, and worked fine earlier today.

The electrodes are free of dust and debris.

Think AGD would replace this if its faulty?

[Jaan]

Sorry, but I don't know much about e-mags, or at least what the charging details like. However ...

When you charge up a battery, there's only so much electricity it can store. When you put too much in, the extra energy is dissipated as heat energy. Think of it as a cup getting filled with water and when it's too full what overflows is heat. Some chargers "trickle charge" so only a small amount of energy goes into the battery, and you'll hardly notice when it's topped off since the amount of heat is small. Other chargers however just dump a lot of energy into the battery and if you're not careful what you described will occur. I've seen batteries melt and packs split open because of this. Some of the cheaper chargers that have both modes don't care what the actual charge state of the battery is ... in fact that can be a little difficult to determine even with complicated circuits ... they simply have a timer circuit which assumes the battery is close to empty when you charge it. These type of chargers can get "confused" sometimes.

I did read the owners manual and it says that when the charger is on green it's in trickle charge mode. Maybe because you took it off the charger it got a little confused and thought it was in trickle mode but was really not and putting too much energy into it, or something like that. Keep in mind that it's difficult to make a very accurate "gas gauge" for batteries, so ergo, it's easy to overcharge them. It might very well be busted too.

I'd probably troubleshoot it first myself, by discharging all the way and recharging it, watching it the whole time. Hopefully the cells haven't become damaged. Don't do that though if you're not 100% comfortable doing it.

[FiXeL]

Overloading a battery can do that. Just like Jaan said, the electronics of the charger maybe think the battery is not full yet, but it is... If you put enough amps on a charging battery it will become hot when overcharged.

Had this once with a RC car battery that was bad and got charged by somebody else on a antique (12 yrs old) quick charger. It became so hot the shrink tube melted off and we were lucky to see it in time.

Check your charger, if it is still ok, get a new battery. Due to the heat the battery could be damaged even though it still seems to work. You really don't want this to happen on you while charging it overnight... :tard:

[doc_Zox]

i saw a thread this week on Tinkers guild wherein a charger melted though a brand new truck's seat

:cry:

[Alpha]

According to the AGD sticker on the underside of my charger, green = done and red = fast charging.

Anyways, I tried using it again, and it charged my battery, and there really was no excess heat.

I popped it open and saw where the burn happened... It was right where the negative wire going to the battery electrode is connected to the board

[11 Bravo]

^^In spite of what the sticker says. Its still charging when the green light is on.