Allan Bowker Posted October 27, 2011 Share Posted October 27, 2011 How effective are Li-Po Guard charging bags? Has one saved you? I'm sure most of us have seen the articles/talk regarding Li-Po fires in RCM&E, BMFA Newsletter, internet, flying club, etc and are well aware of how careful we have to be, especially when charging our batteries. For too long now I've been meaning to buy a couple of 'Li-Po Safe' charging bags to lessen the risk of a garage fire, which thankfully hasn't happened (yet). On eBay I can now get large bags for about £3 each including P&P, no excuse for me to delay any longer. As a sidenote, only two weeks ago a family member had a Li-Po fire when charging. Damage was a hole in the wooden floor and smoke damage.How much of a difference would a charging bag have made? I've not seen/heard any evidence yet either way. I think however they are worth it and should significantly reduce the effects of a small fire. Quote Link to comment Share on other sites More sharing options...
ken anderson. Posted October 27, 2011 Share Posted October 27, 2011 allan-your right in wondering whether to get some or not-i dont use them...i keep most of my lipos in a tin box...... one lad i know was charging his up in the oven at home-he reckoned that if it went pear shaped..it would save the day....... and recently one of our club members burnt his garden shed down(fire brigade ) involved..... while 'topping up a lipo'..... ken naderson ne..1 lipo dept.. Quote Link to comment Share on other sites More sharing options...
Codename-John Posted October 27, 2011 Share Posted October 27, 2011 i suppose batteries might not burn through the bag but as theyre not airtight youl still get the smoke id imagine, so i dont really see the point, just charge them on an fire resistant surface, i use an old ceramic tile Quote Link to comment Share on other sites More sharing options...
Steve W-O Posted October 27, 2011 Share Posted October 27, 2011 I have a steel tool box that my batteries are stored in and they are charged in a metal tin. I use the bags going to the field, my feeling is that they will probably give you enough time to get them out of the way safely, rather than immediately setting fire to the car. I also put my used warm batteries in the bag with the fresh ones to keep them warm on a cold day,no point in wasting useful heat? Quote Link to comment Share on other sites More sharing options...
Allan Bowker Posted October 30, 2011 Author Share Posted October 30, 2011 Having listened to my father-in-laws description of hearing 'a loud bang' when his battery caught fire and watched the explosions on YouTube I started to wonder if a Li-Po Guard bag would hold together. Quote Link to comment Share on other sites More sharing options...
Allan Bowker Posted October 30, 2011 Author Share Posted October 30, 2011 Looks like a bag should hold together and provide less of an intensive burn Quote Link to comment Share on other sites More sharing options...
Tim Mackey Posted October 30, 2011 Share Posted October 30, 2011 OK - controversy hat on - I just don't see the point of these things. If I wanted to store my LiPos in them, then unless I chuck a few all together in one bag, then I would need to buy ( and have space for ) about 60 bags. Putting more than one in a bag, means that should one decide to spontaneously ignite ( which they DONT ) then that ignites all the others with it. That don't sound too clever.If they are purely for charging, then why contain any possible swelling / fire out of sight and smell ? IMO the best regime ( and the one I use exclusively ) is to ONLY charge attended, and have the batteries sitting on a non flammable surface, away from high risk combustibles, and use a good quality charger. The most important bit is to be in attendance, and NEVER leave a charging battery unattended. I admit to leaving them alone for a short while whilst I am perhaps in the adjoining room, but would NEVER leave the premises with a battery on charge. Assuming the running away position now. Quote Link to comment Share on other sites More sharing options...
Allan Bowker Posted October 30, 2011 Author Share Posted October 30, 2011 Agreed Tim, charging in attendance is definitely the best policy, however I'm sure you are in a minority, albeit being best practice. All to often I'm working in the garage with a couple of batteries on charge, only to be called away 'just for a minute' which turns out to be an hour. I think storage in a tin / ceramic box is best for me and then just use a Li-Po bag for each battery that I am charging. I also agree that leaving the premises is a no, no. Perhaps this would make for an article in RCM&E? Edited By Allan Bowker on 30/10/2011 12:49:22 Quote Link to comment Share on other sites More sharing options...
leccyflyer Posted October 30, 2011 Share Posted October 30, 2011 Posted by Allan Bowker on 27/10/2011 19:51:05:How effective are Li-Po Guard charging bags? Has one saved you? I'm sure most of us have seen the articles/talk regarding Li-Po fires in RCM&E, BMFA Newsletter, internet, flying club, etc and are well aware of how careful we have to be, especially when charging our batteries. For too long now I've been meaning to buy a couple of 'Li-Po Safe' charging bags to lessen the risk of a garage fire, which thankfully hasn't happened (yet). On eBay I can now get large bags for about £3 each including P&P, no excuse for me to delay any longer. As a sidenote, only two weeks ago a family member had a Li-Po fire when charging. Damage was a hole in the wooden floor and smoke damage.How much of a difference would a charging bag have made? I've not seen/heard any evidence yet either way. I think however they are worth it and should significantly reduce the effects of a small fire. An original Lipo Sack is fireproof and would have prevented damage to the wooden floor, as it completely contains the flame front. The bags do not suffer from the problem that fully sealed ammo boxes and other rigid containers suffered from in the early tests - namely explosively bursting open due to being unable to contain the pressure. As a result the bags are not completely vapour tight and do not stop smoke damage - their function is to prevent your car, shed, workshop, garage or home from going up in flames. The videos on the original Lipo Sack website demonstrate how effective the sacks are in that regard. Some of the knock-off bags have been show to be next to useless and to lull one into a sense of false security. The designer of the original Lipo Sack - Mark Wood - is a friend - and consequently I wouldn't touch a knock off lipo bag with a barge pole. Credit where credit is due- Matk did the original testing, the original design, sought out the appropriate material and made the original bags. Edited By leccyflyer on 30/10/2011 12:41:32 Quote Link to comment Share on other sites More sharing options...
Tim Mackey Posted October 30, 2011 Share Posted October 30, 2011 Interesting.... and I guess using a "Proper" sack may be a good idea when charging - especially as it still allows a lot of smoke out, which would at least activate one of the two smoke detectors I have fitted into my garage ( where all my home charging is done). I may be convinced yet Quote Link to comment Share on other sites More sharing options...
leccyflyer Posted October 30, 2011 Share Posted October 30, 2011 One other use to which a Lipo Sack may be put is to isolate any crash damaged lipos to get them home from the field. My lipos - which are charged at the field, rather than at home - travel in a fire safe, or, if I'm traelling light, in a lipo sack. If I damage a pack, or if a pack is puffed at the field, it gets isolated an travels home in the lipo sack. Alone. not in with the other packs. I certainly would not be happy to transport a damaged lipo pack in my car uness it were in a lipo sack. Quote Link to comment Share on other sites More sharing options...
Ben B Posted October 30, 2011 Share Posted October 30, 2011 I charge them in a liposack on top of some big ceramic tiles. Not much chance of anything catching on fire then. Time to fess up- has anyone had a lipo catch on fire when it was being charged properly? The times I've heard of have been due to incorrect cell count selection on the charger rather than just a cell failure. Has anyone had one go pop when they were 100% sure they were charging it correctly? Quote Link to comment Share on other sites More sharing options...
leccyflyer Posted October 30, 2011 Share Posted October 30, 2011 Posted by Ben B on 30/10/2011 16:00:09: I charge them in a liposack on top of some big ceramic tiles. Not much chance of anything catching on fire then. Time to fess up- has anyone had a lipo catch on fire when it was being charged properly? The times I've heard of have been due to incorrect cell count selection on the charger rather than just a cell failure. Has anyone had one go pop when they were 100% sure they were charging it correctly? Do you mean has anyone here had such an occurrence? Not me, but the list of lipo failure modes on the ezone, which has been maintained for at least the past six years, has quite a few additional causes for lipo fires, beyond the most common incorrect charge settings. Quote Link to comment Share on other sites More sharing options...
trev Posted October 30, 2011 Share Posted October 30, 2011 I have got 2 of these and use them all the time on the basis that prevention is better than cure and for the sake of a fiver each, they surely have got to be worth it? As an ex marine firefighter, this is my philosophy anyway. The ones I have are the real thing ( i think - they came from a reputable UK source anyway ) and are very very well made, The material is well proven to contain heat as it is the same as the material used to make firefighting suits for the oil industry -very strong too. the design is quite clever as a huge velcro strip seals them ( it requires quite a bit of strength to get them open ) and whilst not being fully airtight, they are tight enough to allow an explosion safely out , keep the fire in and starve it of oxygen at the same time, so in theory should be quite effective. I now work in the explosive industry, I am tempted to set off a detonator inside one and see what happens - if I get round to it, i will let everyone know the results. My bottom line is - spend a fiver and save potentially thousands, a no brainer in my honest opinion but it is only that - my opinion, i have no desire to preach to anyone. cheers Trev Quote Link to comment Share on other sites More sharing options...
Tim Mackey Posted October 30, 2011 Share Posted October 30, 2011 Fair enough Trev - where did you get yours from - LiPoSack ( dave wood ) is US based Quote Link to comment Share on other sites More sharing options...
leccyflyer Posted October 30, 2011 Share Posted October 30, 2011 If they are a fiver each they are probably not original Lipo Sacks, which are about $20 each and available from Lipo Sack in San Diego. Mark Wood is the designer and proprietor of the Lipo Sack. Quote Link to comment Share on other sites More sharing options...
trev Posted October 30, 2011 Share Posted October 30, 2011 Mine are Lipo safes not sacks and got them from a model supplier online in scotland I think it was. Admittedly didnt realise the distiction between safe and sack to be honest so mine are probably not original, so apologies for that. However, that said, they are very well made and are manufactured from a material very similar to oil industry firefighting suit material i.e. aluminised glass cloth. Guess the only way to prove em is to test em - watch this space..........................................Edited By trev on 30/10/2011 23:33:46 Quote Link to comment Share on other sites More sharing options...
Allan Bowker Posted October 31, 2011 Author Share Posted October 31, 2011 Thanks Trev, I'm looking forward to this. Quote Link to comment Share on other sites More sharing options...
trev Posted November 2, 2011 Share Posted November 2, 2011 Will see what I can do Allan, just got to source suitable size and strength detonator now. cheers trev Quote Link to comment Share on other sites More sharing options...
Wiltshire Flyer Posted November 2, 2011 Share Posted November 2, 2011 Looks to me like they are a good idea when charging, would contain any fire (not smoke) and provided you are not leaving them unattended would give you good time to drag em outside. I see the points against the bags but they are not expensive so why leave anything to chance? I still do not see (in my over drive health and safety mind) why these batts are sold and are so popular (well i suppose i see why they are popular) when they are so volatile! Before anyone says nicads are just as unstable etc... i know there is a risk with any battery type, but i never saw nicad safety bags so widely touted and available! Lipo's will die out in the next 5 years i am sure and will be replaced by a far more stable and safe alternative. Quote Link to comment Share on other sites More sharing options...
Doug Ireland Posted November 2, 2011 Share Posted November 2, 2011 I only have a couple of LiPo batteries and only charge them outside on my driveway so these bags are a bit of a waste of money for me. I also store them outside as I dont trust them enough to keep them in the house. Quote Link to comment Share on other sites More sharing options...
Steve Hargreaves - Moderator Posted November 2, 2011 Share Posted November 2, 2011 My understanding was that any LiPo fire was likely to be a short lived but very intense burst of flame & that these bags would contain the flame & stop it setting fire to any balsa/thinners/fuel that might be in the vicinity..... A Pyrex casserole dish would probably make a good place to charge them too..... Quote Link to comment Share on other sites More sharing options...
Barryorbik Posted November 2, 2011 Share Posted November 2, 2011 We use this type of material to house the Ni-CAD and Ni-MH battery pack we use with our products and the proper material is 3mm thick and is actually two interwoven fabrics and has to conform to various BSI and international fire rating standards. The outside fabric is a satin finish silver grey colour and feels rubbery and the inner material feels like silk with a bright silvery white colour and the stitching is a Kevlar thread rated at 450C. A 300mm square piece of the material direct from the manufacturer when purchased in large volumes (over 5,000 pieces) costs us over £12.00, so that is why the correctly made Lipo bags cost so much. In short if any company is selling ready made large Lipo bags for far less than the cost of the correct materials, either they will not be in business for long or they are cheating somewhere!! It's the old adage again 'you get what you pay for' or in this case it may be that 'let the buyer beware' is a better one. Have fun but stay safe Barry Quote Link to comment Share on other sites More sharing options...
Capt Kremen Posted November 2, 2011 Share Posted November 2, 2011 I have (and do use), a pucker LiPo sack as described however ... Most Lipos have very short leads requiring extensions of both charge & balance leads if the LiPo is to be securely 'Velcro' sealed, deep inside said LiPo sack. I have been using two clear glass 'Pyrex/Oven' proof rectangular dishes which nest inside one another but allow sufficient space for a Lipo (3S) to be in the base of the lower dish. This with its charge & balancer leads exiting and connected to a quality balancer/charger. I use the LiPo Sack under the dishes as a degree of further fire/heat insulation. Advantages, as I perceive - I can see & observe the pack for any obvious 'swelling/ballooning' of it during the charge and the combination is not so tightly sealed as to allow any pressure to vent whilst (one hopes) the glassware can contain the temperature in the event of a nasty. For transit to/from the field, I use a large Ammo box with its end clamps very loosely engaged i.e. the lid could lift sufficient to relieve any gas pressure. Packs are held in Tuppaware type plastic boxes inside to avoid shorts and stop packs bashing each other as I negotiate the pothole bumps on the way to the flight strip! The Ammo box is on the floorwell of the car within 'chuck-out-of-the-car' reach if the dreaded white smoke should emit during transit. Quote Link to comment Share on other sites More sharing options...
Chris Channon Posted November 2, 2011 Share Posted November 2, 2011 Hi all, i remember reading a while ago, about John Stennard ( i know it's Model World !) He was in his workshop when he heard a noise, it turned out to be a Li-po venting, not connected to anything just on it's own. so if they can sit there and vent ( sounds like the wife !) then can they catch fire on their own ? would the venting have caused a problem if it had not been caught? I know Timbo says that they cannot self ignite but this was very nearly just that. I am asking because i have just gone over to the dark side of not proper modelling, ie electric . Hehehe, was meant as a joke ( before i start something here ! ) Thank you Chris.C. Quote Link to comment Share on other sites More sharing options...
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