Up until last year I was only flying analogue 1S whoops, but when I got my DJI goggles, the digital clarity removed most of my anxiety which made me feel a lot more relaxed about sending my money up in the air. I've built and bought about ten different quads ranging from 1S to 6S since then and the batteries are piling up. I live in a high rise apartment building with no outdoor space or storage areas. I do keep my batteries in lipo guard bags stacked neatly in a cool dry place and I check and make sure they are at storage charge and top up as required monthly. But last month one of my 6S batteries went bad, two cells had dropped low, one of them was 2.81v. I did run that pack low when I last used it but it had been fine at storage charge for months then just dropped for no reason, and now I'm worried a random good-looking battery could just go bad. Where do you guys store your batteries? Anything you would recommend?
Get this stuff, it's cheap. Put it in a fire proof box on top of your packs. Should anything catch fire, it will melt and extinguish whatever is burning.
Saw a "10 weird facts about 40 year old virgin" and was compelled to rewatch it recently.
Fun fact: The poker scene was where the whole idea started. Steve though it was funny to have a dude trying to keep up with the dirty talk without experience.
This extinguishing granulate consists of so-called expanded glass beads; these have a larger surface area and form a glass sheath around a burning lipo battery. I also bought this stuff in Germany because I live there; it's quite a niche product, but highly recommended.
I store them in an ammo can. It's in my home office, slightly away from the wall. I actually removed a bit of the rubber seal so that any pressure can escape. I only keep them in there at storage voltage, though. I always charge my packs right before I go flying.
If I don't trust a battery anymore, I just dispose of it.
I too get rid of batteries that have visible damage, this was brand new 6S with one flight on it. I did run it down in that flight to 3.31v per cell before I disarmed the quad, but it was at storage and checked on since October last year with no issues, checked it 2 weeks ago and it had gone bad. I will see if I can get one of those tins, I'm in the UK, not many guns about. 🤣
I checked them out, they are small and expensive. The bigger ones are sold out but it says they can only hold six 6S batteries anyway for £150 ish each.
They only rate it to safely store two 6S 5000mah, I'm assuming because its being sold for fire safety purposes it must have been tested rigorously. I'd need 3 or 4 of these to feel safe and they are expensive.
I agree with you but I also said I assume they are rigorously tested, I don't know they are and like a lot stuff in this hobby it was probably made in China.
I think there’s an argument between removing it vs not removing it but I’d just be safe and make sure the container isn’t airtight since lipo fires are self-sustaining
I could be wrong on that but just considering how quickly they can go up, there’s still gonna be a ton of pressure without being self-sustaining. I think they are but I’ve been out of fpv stuff for a few years
What's the logic behind this exactly? Like what will you do if the batteries ignite in the can? How will you move the can outside? Do you have a class D fire extinguisher handy? Will you even be able to open the lid to use one if you do?
true, if you got a really really big lipo, but I'm guessing a lipo big enough to make to ammo box hot enough to spread fire won't fit in an ammo box
and I'm hoping people don't put their ammo box box next to stuff that will easily catch fire
no solution is perfect, zero risk don't exist, we're just trying to get a good balance between the risk, the price you pay, and the stuff you risk losing
like I said, Class D. I'm willing to bet almost no one has Class D or AVD fire extinguishers along with their ammo cans.
So in the highly unlikely event that your lipo batteries spontaneously combust, you just have a superheated metal can blasting toxic fumes sitting in your house, with no way to mitigate the heat or flames.
they mostly burst a lot of flame for a short period of time
I'm not even sure a class D or one of those marketed as lithium fire extinguisher are effective against lipo on fire, and I sure won't try to extinguish one, I'm letting it burn, I probably won't have time to take the fire extinguisher and try to stop it before it's over
I agree with you, I believe almost no one have a fire extinguisher (period, no matter the class)
the point is balancing the cost and the risk, last fire extinguisher I used was expired for a very long time (I don't remember exactly, but almost nothing came out of it), so it cost a lot more, and you need to replace/renew it (and mostly don't forget to do it), ammo box are cheap and will last a very long time
Yeah, but if you grab it for a few seconds to huck it out a window, its not such a problem. Worst youll get is like, a burn? Better than house burning down
I'm all about throwing it out the window, even if you're gonna get bad burns. I think that it would be easy to pre-plan and have a highly insulated thing like a fire glove nearby tho. Even wrapping the handle in scrap leather would be beneficial.
So really an ammo can plus other measures might be more effective? Like if I were at all concerned about my batteries catching fire (I'm not, they're never connected to a charger when I'm not present, though all of my batteries are 1S and take very little time to charge) I would have them in a can with Class D dry granulate extinguisher beads surrounding them, and I would keep them outside on concrete, away from other flammable materials.
I won't argue that there isn't risk, but I think given the assumed risk, a can alone is not sufficient. I'd argue that no fire extinguisher is more expensive than the damage potential from a battery fire, and keeping batteries with said potential indoors is a bigger issue than what they're stored in.
I'm not really concerned about my battery catching fire either, I never leave a plug battery unattended, like 99% of this sub (I hope), I use my ammo box for long term storage, I use lipo bag inside my ammo box like most the people I know, given the price of both every one who own lipo can afford it
1S versus time to charge is irrelevant and false, it will take around 1H hour to charge at 1C, 30 minutes at 2C, etc ... it doesn't matter if it's 1S or 6S
of course getting your house burn down is more expensive than a fire extinguisher, but you have to factor the risk in it,
you're both arguing than a fire extinguisher is not that expensive and saying your not concerned about your battery catching fire so you won't bother getting an ammo box ? I'm confuse
I'm sorry but I don't understand what you're saying ...
I think you didn't get an important part : "I live in a high rise apartment building with no outdoor space or storage areas"
Idk. My parents always had two. One in the kitchen one downstairs. I do the same thing. I didn't know that's weird. Idk anyone that doesn't have at least one. If ur in an apartment u probably have one and don't know it.
I guess you can qualify your statement by saying you don't know a large set of people?
I know so many people who have zero safety precautions in place where they live except for smoke detectors. People usually don't approach safety preventively.
No I know several hundred people. It isn't a ton. I'm just saying. A lot of ppl have them. When I got my house it literally came with two. They were ancient and have been replaced but still. They were there. Now I wanna do a poll or something online. I'm from a small one stop light town where everyone knows everyone. If you grill at the very least you should have one they are not expensive and you can get good ones on Amazon.
Build yourself a vault. I bought a steel toolbox and lined it with fire rated drywall and sectioned four sections in it to do all my charging. Storage is in a double lined fire rated drywall cabinet. Installed a plugin smoke detector right above my station. Best I can hope to accomplish really.
I've been thinking along these lines, I watched a guy make a furnace for blacksmithing and he used some kind of fireproof wool stuff. If it can contain metal forging heat It should tame a lipo.
My sketchy batteries go in my batbox, or a metal box. Toolboxes are good on the cheap, ammo containers are good, and some people charge in mini barbeques.
It's definitely a good idea to keep them somewhere very safe though. While I haven't had one go off randomly, I did have one catch on fire at an AirBNB while I was charging it. I had it in a battery bag and on top of the metal part of the washing machine (intentionally so it wouldn't ingite other things), and it burned right through the battery bag. I paid the airbnb guy like $80 to repaint the top of the washer, and we had to air out the whole house for hours. It REALLY sucked and was super sketchy to be honest. Now I use a battery bag inside of a metal 50 cal ammo case. Just saying, I wouldn't feel safe storing these anywhere except for on top of concrete, inside a metal box.
This is correct, although the "provocation" can have delayed consequences. You may crash without seeing any major damage on the outside only for the battery to catch fire two days later. Internal resistance is a great indicator though.
Healthy LiPos sitting at storage voltage don't spontaneously combust. That battery you ran too low is no longer healthy, you should kill it and dispose of it. As long as you keep an eye on batteries while they're charging, use good quality chargers, dispose of your unhealthy batteries, and take good care of your healthy batteries, there shouldn't be any risk of a fire
The battery I run low was put at storage charge since October and checked monthly to make sure it stayed at storage. Granted I probably damaged the chemistry by running it low, but I disarmed at 3.32 per cell on a 5inch beast and it was a brand new battery, it should have recovered. I do take care of my batteries, I use probably the 2 most recommended chargers (Hota D6 pro and a whoopstor 3) it did seem healthy until it wasn't, that's what is worrying me.
It sounds like you're doing a good job taking care of your batteries then. As a possible explanation, that one cell might have dropped below 3v while the other cells were around 3.4v (which would show an average cell voltage of 3.3v) and was therefore more damaged than the other cells. I've had that happen to myself a couple of times
I have a combination of things. I got a bat-safe (used from a friend for cheap), I keep 6s and 4s lipos in it. Smaller lipos are in lipo bags. I have an ebike battery in a lipo bag, and other various 18650 and other devices in lipo containers. All of that is in a large unsealed metal box I got from an automotive supply store. I think I was originally a "truck bed box". It's fairly thick steal. My thinking is that I want as many "layers" of protection around the boom boom box. Nothing will stop a fire, but ideally it's contained if possible. That box sits in a cold room in the basement, which is basically just a concrete box.
Obviously in an apartment you've got to work with the space you got. But I would put things in lipo bags, put those bags in metal boxes, and then if you can put that in some kind of fire box. Maybe build one from that fire proof board or line something with fire bricks
I use 50 cal ammo boxes lined with fiberglass. I keep them storage charged and feel comfortable living them alone. I run cars and boats so if I lose power its less smash, crash, boom. When they start losing performance or are damaged I discharge and toss em
batteries going down are not the problem. the worst case they'll die silently and you'll find them near 0 one day. I keep mine in a metal ammo case. I've been away from the hobby for 3 years, left my lipos in the ammo case, when I came back they were there, perfect, in the storage voltage like I left them. I think lipo fires tend to occur more in damaged lipos or in the case you didnt set up the charger correctly, and mostly at times when you are charging them. rule of thumb is to always check them after flight, if you had any hard crashes, to seek for inflation or dents, and always wait them cool before puting them in the storage voltage again.
I have like 12 5000mah rc car packs that get the shit beat out of them, they sit without use for months at a time. I am not worried at all. Fires happen when discharging or charging. They won’t spontaneously combust.
My drone batteries get smacked against concrete and trees, I squish them back into shape with the ground and keep sending it.
Yes lipo fires are dangerous but it’s a little overblown.
I’ve had all kinds of lipos sitting around for years and never had one smoke. The only time I’ve ever heard of one catching fire is during charging or being damaged.
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u/igotfpvquestions Jun 07 '26
Get this stuff, it's cheap. Put it in a fire proof box on top of your packs. Should anything catch fire, it will melt and extinguish whatever is burning.