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Old Jan 29, 2013, 10:57 PM
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USA, CT, Wilton
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Avoiding those $@#$^!! Fiberglass splinters

I've got a handful of those really cheap battery bags. On the plus side, there's the additional protection against burning down the garage/car/house you love. On the negative side, unlike my Thunder Power bag, which is lined with a sort of mesh/felt, these just have woven fiberglass. Reach into the bag to get your batteries, and you pay the price in fiberglass splinters.

I thought about spraying, or thinning that liquid electrical tape or tool handle stuff. I also thought about switching to a small fire safe, or making my own bags out of ebay-sourced silicone, but in the end I chose the simplest route: line my bags with foil tape.

I wore long-sleeves and gloves and went to work with a series of strips, and folded over the front edge by just a quarter inch, sealed with some hot glue. The foil tape is good to 300 degrees, so I'm hoping in the worst case, it doesn't add to the destruction.
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Old Jan 29, 2013, 11:03 PM
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United States, CA, Bear Valley Springs
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*smack* You could have had an original LipoSack (channeling V8 commercial).

mw (we don't do splinters)
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Old Jan 30, 2013, 07:53 AM
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Quote:
Originally Posted by Merkin77 View Post

On the plus side, there's the additional protection against burning down the garage/car/house you love..
REALLY????????

Check out the test video of this bag. I wouldn't depend on that bag to protect my garage/car/house.
Lipo Battery Fire Containment Test (2 min 40 sec)

See more tests of other bags. Just because the vendor says it works doesn't mean a thing.
http://www.rcgroups.com/forums/showp...6&postcount=14
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Old Jan 30, 2013, 08:11 AM
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United States, AZ, Tucson
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So with all this testing I still don't know how to safely store my lipos. For now I have them in a metal cash box and the box is sitting in my brick lined fireplace. It is too hot in Arizona to store anything in the garage. I figure at least with the box in the fireplace with the flume open wide the fire should at least be contained. Also the air conditioning in the home keeps the storage box cool all year. I have been thinking about buying a few amo boxes soon. But storing or charging a lipo in the Arizona heat cant be a good thing.
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Old Jan 30, 2013, 08:29 AM
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Originally Posted by goldsworthy View Post
So with all this testing I still don't know how to safely store my lipos. .
Go here and look at Videos of LiPo Container Tests. Many different and cheap ways to store lipos. Buy a cheap fridge?
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Old Jan 30, 2013, 09:17 AM
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United States, MN
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You really don't want to see how I store my small lipos My 6s are in a "storage" liposack, the little ones... eh on a wooden bookshelf with lots of other crap in my basement closet. I don't abuse my batteries, I'm really not that worried.

I also don't see the point in storing many of them together in a confined space. The liposack I use for my 6S is one of the "storage" ones that has compartments. The sack is containing all that energy and heat and I can only guess that without compartments you are looking at a nice runaway reaction from one battery to the next. I would think it's not a matter of if your cheap bag will fail but when. Which is true of the cheap bags even if you only have 1 lipo in there.

I would seriously suspect that the chances of your children burning down your house is higher then the chances of a stored properly treated lipo burning down your house. Contrary to popular belief lipos don't spontaneously combust while sitting in storage.
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Old Jan 30, 2013, 09:52 AM
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To my knowledge, there still isn't one accepted practical (cost/portability) way to store these cells and be 100% safe, especially when you're talking about two or more dozen batteries. I've read through most of those posts (my favorite is the ammo box with the bb trap and muffler, though I wonder if that would be able to vent enough or still blow out the sides - also the Sentry fire safe might be okay, but would need a few of them). I also question if there's a difference between how a pack fails in the wild vs. what's being done to get them to go off for the purposes of a test.

That doesn't mean that an average effort with safe practices (charge responsibly, don't subject them to heat, when possible keep them from combustibles, smoke detectors, etc.) is in vain.

I plan to experiment with some silicone sheets (anyone seen this tried before?) and I have an old triple-layer nomex racing firesuit as well, until then, those cheap fiberglass bags are likely better than no bag. And, if you're using those, then not having splinters is a good thing, and maybe one more barrier against the heat/flame of a pack gone bad is a good thing too.
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Old Jan 30, 2013, 09:58 AM
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Quote:
Originally Posted by Merkin77 View Post
I also question if there's a difference between how a pack fails in the wild vs. what's being done to get them to go off for the purposes of a test.
There is a huge difference. Most tests you see they put the charger on nimh and way over charge the battery. There's a ton more energy there then there is with a battery at storage voltage. It's all about the energy level. Think about it for a second. If you drain a lipo to 0v you can safely drop it in the trash, you can cut it open and take it apart with no risk. So is the lipo sitting on your shelf at storage voltage going to blow up with the same force/reaction as the over charged one in the video? I guarantee you it is not.
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Old Jan 30, 2013, 12:48 PM
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Originally Posted by grimbeaver View Post
. Contrary to popular belief lipos don't spontaneously combust while sitting in storage.
Unfortunately that isn't the case. Here are a few examples of non charging "who knows why" fire incidents or why to store your lipos in a firesafe (non-flammable) container.

"Had been (past tense) storing my lipos in a ceramic tub-no lid. Luckily I was home and went into "airplane" room and found one of the lipos was on fire, on the carpet, and was able to prevent damage or far worse. AND I WAS NOT CHARGING THEM. Since that incident, I store them in metal ammo box (drill 2 holes about 1/4 inch diameter for venting) and in lipo bags. Charging is in the lipo bag. To this day, do not know why the battery just went "crazy". Hope this incident may be helpful to someone: charge (don't leave room) and store in some type of fireproof container. bdel"
http://www.rcgroups.com/forums/showt...e#post23648998


"WOW had a call from my partner whiles at work about my opti power lipo blow up, and the thing is its wasn't even on charge so am a bit confuse to y this happen, I did notice that they were starting to puff and funny enough i did rang opti power yesterday regarding the battery puffing and they said to send them back and now this happen today, but the most thing I was happy about is that she was at home other wise I could have lost" http://www.rcheliaddict.co.uk/main-d...tml#post877508

"A mate at our club this evening had a luck escape, a brand new Turnegy 5000 went up in his kitchen! no apperant reason (not on charge), he managed to get it out in time but i guess a bit of a freak out for his wife, little'un and himself. so remember lipos realy can burn the house down be carefull folks!"
http://www.rcheliaddict.co.uk/main-d...tml#post831920

"Bought a couple of ThunderPower G6 1800 3s's and ran one in my parkzone mustang today for about 5 minutes (timer )of balanced flying. Packed the plane up took the battery out and put it back into a zip lock bag... One of the cells exploded while carrying it back to the car? For a brand new pack that had been discharged and balanced im pretty amazed?"
http://www.rcgroups.com/forums/showp...postcount=1136

"Bro's just had a very close call, A brand new battery never crashed a 2S 480 mAh was just sitting there it was not used or charged on this day.. I was up stairs and heard a loud pop, I go down stairs only to find the lil' battery spewing grew smoke & spinning then it blew up ! Big flames. It almost cost me MY HOUSE, this darn lil' battery all by itself did this, I have learned my lesson all batteries are now stored on ammo cans, DO NOT STORE LIPOS, in the open !!!!!!!!!!!! Look what happened to me !!!!!!!!!!!!!!!!!!!! It managed to burn the wall, carpet,and tile.......Never again !!!!!!!!!!!!!!!"
http://www.rcgroups.com/forums/showp...postcount=1098

"After flying this morning I was doing some repairs and all of a sudden i heard a pop and smoke started pouring out of a Flightmax 3s 1300. I had not flown that pack. I just brought it home unflown. It was just sitting in the concrete block I store it in. I have a bucket of sand on hand that I dumped into the block and put its concrete top on. Smoked like crazy. Stunk up the cellar. There was another 1300 in the same block. The voltage on that measures fine but I don't know if the heat from the venting pack up against it might have damaged it? Now I am a little wary of my batteries. I treat them well. Have only charged them at 1C and do not abuse them. I recently balanced the pack. That was a small 1300. I recently got 6s 5000's".
http://www.rcgroups.com/forums/showp...85&postcount=1
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Old Jan 30, 2013, 01:14 PM
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I'll address a few of these..
Quote:
Originally Posted by hoppy View Post
"WOW had a call from my partner whiles at work about my opti power lipo blow up, and the thing is its wasn't even on charge so am a bit confuse to y this happen, I did notice that they were starting to puff and funny enough i did rang opti power yesterday regarding the battery puffing and they said to send them back and now this happen today, but the most thing I was happy about is that she was at home other wise I could have lost" http://www.rcheliaddict.co.uk/main-d...tml#post877508
Ignored a warning sign. This was not a healthy lipo, precautions should have been taken. And not too sure about opti power if they recommended he ship back a clearly damaged lipo.
Quote:
Originally Posted by hoppy View Post
"Bought a couple of ThunderPower G6 1800 3s's and ran one in my parkzone mustang today for about 5 minutes (timer )of balanced flying. Packed the plane up took the battery out and put it back into a zip lock bag... One of the cells exploded while carrying it back to the car? For a brand new pack that had been discharged and balanced im pretty amazed?"
http://www.rcgroups.com/forums/showp...postcount=1136
Battery was in motion. I stated a "stored" battery. Anytime battery is in motion it is possible for solder joint to break.

As for the rest, I suspect there is more to the stories then has been told. If it was really that high of a risk to just have them sitting around there would be warehouses bursting into flames left and right.
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Old Jan 30, 2013, 01:24 PM
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So Thunder Power has been making packs for years. Not sure when this article from TJinTech was written but....
Quote:
Jason informed me that they assemble every pack they sell right there in that building with the exception of the tiny micro packs.
So needless to say they have a lot of lipos in their warehouse.

Quote:
I asked Jason if they had ever had a fire in the warehouse, you know since they are a lipo assembler. He said the last fire they had was from an over-taxed electrical strip in an office. It did spread to the warehouse though, and they lost a great deal of their inventory from it. He said the fire burned for a whole day and firemen could not put it out. Since then they have rebuild the burnt parts of the building and have taken the opportunity to change the floor plan some, as well as add a sufficient number of outlets
So the only fire they have ever had was not even started by a lipo. Seems like by your logic if it's that common it should have happened by now for them.
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Old Jan 30, 2013, 01:31 PM
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And just for fun since I made the comparison in my earlier post, from the National Fire Protection Agency:
Quote:
In 2010, U.S. fire department responded to an estimated 44,900 fires that were started by someone, usually a child, playing with fire.
Pretty sure if more then 45,000 people's homes went up each year from a Lipo we'd be hearing about it.'

It's all about risk assessment. You can do everything possible to keep your house from burning down (from any ignition source) but ultimately you can't guarantee it.
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Old Jan 30, 2013, 01:40 PM
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Quote:
Originally Posted by grimbeaver View Post

As for the rest, I suspect there is more to the stories then has been told. If it was really that high of a risk to just have them sitting around there would be warehouses bursting into flames left and right.

Look at the difference between an RC user and a warehouse.
Warehouse - Unused, 1/2 charged. undamaged batteries.
RCUser - Frequenty used, possibly dropped/over discharged/over current discharged/over heated/stored under non ideal conditions/ etc

I don't doubt there is more to the stories, but the important thing is the user believed he was treating them OK and had no explanantion for the ignition.
Yes, unexplained ignitions are infrequent, but happen ofter enough not to disregard the danger during storage in my opinion.

What is the benefit of minimizing the danger?
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Old Jan 30, 2013, 08:27 PM
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Originally Posted by hoppy View Post
Unfortunately that isn't the case. Here are a few examples of non charging "who knows why" fire incidents or why to store your lipos in a firesafe (non-flammable) container.
Should re-state then.

An undamaged LiPo in storage has a VERY LOW chance of catching fire.

I would not be surprised if most of the storage fires have been from a damaged pack (you cannot always tell easily). LiPos are pretty fragile, using strong velcro stuck to the pack or very tight straps can cause damage, over time enough to result in an internal short and then fire.

They really should have a protective shell, or at least a couple of FG/CF/Metal plates top and bottom to spread the loads.
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Old Jan 30, 2013, 09:34 PM
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This is why i don't get why bother storing @ 3.85V per cell ? why not just store at lower voltage like 3.4V if you are not leaving the packs for a whole year the lipos should not drop that much voltage in a few months.

this way they will have so much less energy in them they won't catch fire when stored for a few months at lower voltage like 3.4V per cell?
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