slrdave

My Feedback: (1)

I can say from my experience that the smoke detector went off before there were obvious signs of smoke in my basement, so yes, they do work.

slrdave

My Feedback: (1)

This is expressly why almost every Li-Po charger has a storage setting. NEVER, NEVER, NEVER fully charge a Li-Po and store it! Li-Pos are supposed to be stored at roughly 50% capacity.


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I think that storing a fully charged lipo is not a safety issue, but rather one that effects longevity of the battery. The Thunder Power website only mentions storage charges when putting batteries up for the winter (i.e. long-term). Unless a battery is way off-balanced I can't imagine how keeping it at a full charge for a few days is un-safe. I think the battery in my basement would have gone off even if the voltage was slightly lower as long as the voltage between the cells was sufficiently different. I'm pretty sure that my mistake was not checking for this after I charged it.

David

David Searles

My Feedback: (49)

OK, I'm officially concerned!

So, can we now steer this thread more towards solutions. I can honestly say that I never charge my batteries unattended, but, I do & have left them installed in the jet while charging. My big concern now is the storage risk. Below is a photo of what my trailer typically looks like: six to eight jets, all containing three or more lipos! Even if I make the effort to remove all of the batteries, where the hell do you safely store 24 lipo batteries?! Put them all in one box or cabinet & it seems to me you've just created a battery bomb, ie one goes off & it triggers the other 23! I really would rather not have a battery go off and destroy every jet in my trailer, so it seems the storage solution needs to be external, and somehow compartmentalized so that one bad cell can't set the whole thing off.

Suggestions?

David S

CraigG

My Feedback: (40)

Good question David.....and oh by the way, aren't some of the batteries in our cell phones, Ipads, laptops and other PDA's also LIPO's? What about them? What is the practical answer to dealing with this hazzard?

I have already switched all my jet ECU's and Rx's to A123 but still have lots of foamy LIPO's around, in addition to the aforementioned PDA's. I want to be safe but now I'm not sure how.

Craig

tucson

My Feedback: (1)

Hi David,

That is exactly why I got rid of my Li-Po's and went to A123's.

I want nothing to do with Li-Po batteries. This thread explains why.

Stan

PropsnWings

My Feedback: (9)

I have been thinking some on this same issue, with the compartment type storage. I currently have a fire safe I keep my LiPos all in, and have thought too, that I have a battery bomb in essence. I am seriously thinking of fabricating a metal box that can keep the batteries all seperated with metal dividers...... but then came the thought of how heavy this box would be , even empty.

aspeed

Metal boxes could conceivably short a battery at some time too. Outside isn't the answer either because of freezing and heat.Nicads seemed ok in the freezing, but not lipo's.All I can come up with are ceramic or clay pots that have a good seal if they do start a fire. Maybe a Mason jar or something similar. I have had good luck with my LiFe batteries too, and they are almost bulletproof as long as you don't drain them to zero. There is a weight penalty as well as size in some cases. In my case I needed a bit of nose weight anyway. You can charge them in 20 minutes too, and get more charges reportedly. I have only got maybe 25 flights on mine so far,but some dune buggy guys have said much more. It looks like it may be a problem getting batteries soon too. Shipping is being stopped on international flights here. We may have to wait for the slow boat from China.

raptureboy

Whoee! Wish I had that kind of money or maybe a wife that would let me spend that much money on toy airpalnesBut really, we need some real expert advise here an not just antidotal evidence and hearsay. I have some lipo's from 2003 thatI still use to power a smoke pump. They don't even have a balance tap.I even have some that have bad cells and won't charge now for a couple of years laying around. What we don't know about all the incidents listed here is just how were these batteries maintained and used. There are just too many variables going on. These things are being used by the millions all over the world and if this were epidemic then we should hear about it all over the news. There are definite do's and don'ts when it comes to charging, using and storage. Google lithium battery fires and here is what you get http://www.bing.com/search?q=lithium...c=IE-SearchBox over 16,000 hits. All kinds of info on testing, fire fighting, etc. Read on and don't forget that battery on the charger while yourreading.

PropsnWings

My Feedback: (9)

It was not until recently that I had any LiPos around. I have recently gotten into some electrics and of course the batteries are LiPo. So I have been learing all I can, as I had already known they were a dangerous breed if not respected. So has A123's been used for electrics? I am surprised they havent if not.

dbsonic

My Feedback: (3)

+1 on clay pots and cinder blocks for storage.
old Weber BBQs with vent holes too.

raptureboy

Faa test http://www.fire.tc.faa.gov/pdf/syste...y_04112006.pdf

jetpilot

My Feedback: (48)

I always charge batteries seperately. I always make batteries removable. This is a must. They have to be removable! Charge in a safe area. Goes for all types of batteries. Ive had Nicads go bad. I had a Nicad short out in my car when I first started flying years ago. I pulled over and kicked it out.
I keep all of my batteries stored in a metal case which is very accessable. I would much rather pull over and kick out a case of batteries instead of watching my jets burn down. So what if you loose a case of batteries, its much better than a trailer of jets.
I keep them in the same case at home.
I heard that Lipos create their own oxygen so maybe it is a lipo bomb. rather they burn themselves up instead of my house or trailer.
Scott

dbsonic

My Feedback: (3)

Good info, report says venting at 470F. So maybe the temp sensor setup to cutoff during charge is an effective way to go.

David Searles

My Feedback: (49)

Is the key to safe storage that they not be fully charged? Typically after a weekend or event of flying, I leave the batteries installed in the jets at whatever level they have been depleted to. Then a few days to a week ahead of the next event i take each jet out of the trailer and individually charge the batteries to full while the jet sits on the pavement in my driveway, & I work in the garage with the garage door open and a fire extinguisher nearby. I then replace the jet into the trailer, so that everything will already be fully charged when I arrive at the field. Typically, then, the batteries are stored fully charged, for no more than a couple days prior to using.

This has worked great for the past four years, but, now I'm wondering if there is a better/safer way to do this.

David S

sskianpour

My Feedback: (2)

Just out of principle, this must be the most awesome photo in the history of RCU!!!!
Nice Dave!!!! [8D]

Shaz

GSR

My Feedback: (145)

I use a old disabled toaster oven set on brick to charge and store them. Scotty
Used to use my wifes kiln till she sold it.

aspeed

For post #109 (I don't know how the quote thing works) A123 batteries work fine for planes and especially cars and boats.  They are about 1/3 heavier than LiPo's, and the normal arrangement are shaped like a big D cell battery, so getting three together can be hard to fit in a skinny fuselage.  I tried them in my old Amptique glider and it worked fine, much better than the old nicads which barely went 100 ft. high on a charge.  I got at least 5 or 6 really high lifts out of a 2 cell 2300 mah A123 copies.  About 7 minutes altogether.  LiPo's would be better as they are lighter for lift and glide too.  I know this is a jet forum.  Dune buggies are less sensitive to weight and are good candidates for A123, but for all out racing the voltage of 3.7 for LiPo's is better than 3.3v for A123.  A123 is easily safer for charging and crashes etc. though.  They were developed for real cars.

tucson

My Feedback: (1)

You are correct this is a jet forum.

I fly jets as well as Prop warbirds. 123's are not a problem for space.

Stan

lov2flyrc

My Feedback: (24)

So....Giving this a little thought in terms of storage safety..... Thinking aloud...

What about something like an ammo can with dividers to separate the packs. In the lid, perhaps a sack of some sort filled with sand. If a pack goes off in the ammo box, the sack holding the sand melts and the sand dumps into the can snuffing out the fire?
Seems we could come up with some sort of insert that you could put into a standard size ammo box for both the separators and the sand bag!

dbsonic

My Feedback: (3)

You could. The ammo box has the advantage of portability, but the cinder block has 2 or 3 compartments already and youtube vids show the idea of a ziploc bag of sand to snuff the fire. Works really well. credits to utahflyers.

http://www.youtube.com/watch?v=ZNxLGDwGw-k

lov2flyrc

My Feedback: (24)

Interesting video.... seems to confirm an Ammo box with sand may be the perfect setup. Going to toy with this a bit when I find some time!

raptureboy

I was thinking on the same lines. perhaps the cement board used under tile that can bepurchased at homecenters. With a ziploc back of sand duct taped to the inside of the lid. Going to look into it.

rcjets_63

My Feedback: (4)

It's such a PITA to remove the batteries to charge them, but I'm not letting my airplanes (or me) catch on fire due to some malfunctioning LiPo. As such, I bought a durable battery container to mount in my T-28. It will increase the wing loading a bit, but SAFETY FIRST! I also picked up a protective suit to wear whenever charging LiPo batteries.

Jim

raptor30se

Here is an exert from a post on runryder about the corrosive nature of the smoke. I always felt I could keep a fire at bay but the smoke issue was a driver to put them out of the main house.

GMPheli

Elite Veteran
W. Bridgewater, MA USA

The best thing to store them in is a either a ceramic or metal container with a vent to the outside. The fumes that come off burning lipos are very caustic. If you just store them in say an ammo container, and they do burn. The room that they are stored in will get covered in the smoke which can causes a lot of corrosion. This is from a post from Peter Wales:

I had a lipo fire in my shop a few years ago, The LiPo was in the middle of a bench by itself and burnt the bench pretty bad, but that was all that got burnt.

The smoke left a carbonish deposit over all of the walls and all the paint needed sealing and repainting. Every piece of steel in the room went rusty, including my mill, lathe and pillar drill. All my tools went rusty as did every bolt head and nut on all my helis.

The smoke settled and left a fine dust everywhere.

The AC unit sensed the temperature in the room had increased so it turned on and sucked all the smoke and fine particles into the duct system depositing them in the next rooms. The particles were too small for the filters to catch them. The other rooms needed painting. All the cloth needed replacing as the fine dust had a high carbon content so when you touched it, it left a black streak. My wifes dresses in the closets and all of her hundreds of pairs of shoes needed replacing as they couldn't be cleaned.

You can contain the fire damage with LiPo sacks and other things, but the smoke will do a lot of damage and if you charge them up in your garage, just have a look and see how much steel is in there which will need cleaning or replacing.

rem0.061

My Feedback: (30)

I have thought about getting a lipo bag for a long time, but now I have seen too many lipo fires. I'm checking my tower hobbies catalogue for prices right now. At least I have plenty of ammo cans to use.