Charging box

[ChrisS]

Tim and myself have been mulling over the issue of safety in regards to the charging, storage and transportation of Lipo batteries. It occures to us that while we have talked about the use of fireproof containers and safe places, no one has really made such a thing readily available to the modeller.

We are thinking about purchasing a quantity of "firesafes", punching a hole in the side and installing a few connectors for charging.

What a firesafe is is a cement box that is wrapped in plastic. The idea is that if there is a fire, the plastic melts and seals the thing shut...simple and effective.

Waddya think?

Chris

[jwooten]

A lot of people have been using those. I have not heard of anyone who has had a fire in one. Most of the fires reported have been while people were recharging. I prefer to recharge some place that if they burn nothing gets hurt. On a Bar-BQ grill is one suggestion. The box should be as good as most things for storage and cheap. It is better to assume that something will happen than to be sorry.

Jimmy

[larryf]

Chris,

I use a sentry firesafe from homedepot. The problem is it isnt big enough for the 5s packs....

I think it is a great idea to use the firesafes...you never know. I also use mine for transporting my smaller packs to the field.. it also acts as an insulated box so that the hot car temp doesnt reach the batteries...


i say make them and sell them...

Larry

[ChrisS]

"The problem is it isnt big enough for the 5s packs.... "

Aaahhhh, but with the Ion-X packs, I'll bet it is. The Ion-x packs have the cells up on end and the wires running across the bottom.

Just a thought here guys, trying to make things as safe as possible.

Chris

[rotorheadbob]

Chris,

I'm on the waiting list at HeliProz for an Ion :D , I'm most interested in the fire safe. Grown fond of the house! I think this needs to be explored with the recent rash of fires being reported by the AMA and others.

What's the weight of the fire safe so far? How does it compare to other firesafes being sold? I know that Office Max sells them. Are they anything alike? The go for about $250 (I don't recall the exact price), and were rated at some temp for 2 hours i believe.

Thanks for looking into this for us all!

[larryf]

actually my firebox was only$20 at homedepot but it is a smaller model.....

when i charge i have the batteries in it and prop the cover open.. with a smoke detector at the bench.

this way if anything goes wrong i just pull what is proping the cover open and the safe is closed....

[ChrisS]

Yeah, those are what we were thinking about (and I have been using), just a simple $20 safe with hole for connectors in one side...simple, easy, effective.

Chris

[Russ McC]

Chris,

This sounds like a good idea but it also sounds heavy. How heavy is it? Assuming this is heavy could something lighter be made to work? :)

[Shannon Davis]

How about surplus ammo boxes-- are they big enough?? steel don't burn, and I dont think the batts. have any explosive force when they fail. A small hole for charging would not allow enogh air to support a fire of any size. :?

[ChrisS]

Yup Shannon an ammo can would work fine. The fire safes weigh like 10 to 15 pounds. I don't think there is any real explosive force either, just a kind of splatter from what the video shows.
Chris

[Russ McC]

Chris,

The ammo box sounds good but the 15lb safe sounds ok to, I don’t know the safe you’re using. Can you get us a pick of yours? :)

[ChrisS]

O.K., let's see if this will work...a couple pics of the box I have been using.
Chris

[Shannon Davis]

is their any "off gassing" when charging a Lipo-- do we need any vents????

[ChrisS]

No, if there is....you've got problems

Chris

[Shannon Davis]

would these problem gasses be explosive- I wuldn't want to trap them in a box if so- Or maybe I would. :?

[rstacy]

Has anyone had a LiPo pack explode or over heat?

Did you do something stupid to make it over heat?

Every pack that I have ruined was because I tried to charge it at too high of a rate or the charger screwed up. (MRC Super Brain 969)

When I follow the rules, my packs are fine.

[ChrisS]

I have been using these large packs for the last 1.5 years and only once have I had a problem and that was due to the fact that I over-discharged it. It got hot, like 180 degrees and swelled up a little. The next time I charged it, it's capacity was down like 30%...I sent it back to Thunder Power. Since then I have always stayed off the limits and (knocking on wood real hard here) I have not had any further problems.

I agree 100%, if the rules are followed, the packs will be fine.

The fire safe is just a precautionary measure. It is NOT meant as an excuse to get complacent.

Chris

[jwooten]

I have had 2 large packs swell. These were new packs and were not overcharged or undercharged. If I had not reconized the problem and stopped using them, I Probably would have blown them. They were replaced free of charge.

Jimmy

[ChrisS]

Hi Jimmy
Were these TP packs? I have heard of manufacturing defect type problems with some of the other brands but not the Thunder Power batteries...just curious.
Chris

[jwooten]

No, they were tanic. I suppect a bad weld, but cannot verify.

Jimmy

[ChrisS]

Good to know...thanks Jimmy.
Chris

[GGoodrum]

Chris is right, there is not any "gassing" that occurs with normal charging. The cells are completely sealed. If a cell has a puncture, it will emit a very distinctive "sweet" smell from the Lithium. DO NOT try and charge any pack that has such a puncture.

When the cells overheat, due to a short, overcharging or from trying to pull too much current for too long, they will expand, or "puff". Eventually, they will burst and will "flash" into combustion as the heated Lithium is exposed to the air. I don't know how much of an explosive force that will be, but I do know you don't want to be near, if it happens!

[Ben74]

here's a charging box my buddy and i designed. it's just a couple of cinder blocks with the middle walls busted out. the top one is wrapped in saran wrap and filled with sand. if a fire starts, the plastic will melt and dump sand on the batteries. it's very cheap and easy to make.

[WillJames]

That is a VERY smart idea with the sand and plastic wrap!! SWEET and SAFE!!

Very nice work!!

[ChrisS]

Very cool Ben
Thats much better than the firesafe thing.
Chris