You can see the archived poll results on the Wayback Machine:
https://web.archive.org/web/20221220093741/https://budgetlightforum.com/t/-/72777
Just curious, I would like to know how people store their cells.
I mostly use LiPOs (the pouch batteries, not cylindrical) and one of my cells expanded after being left fully charged for a few weeks.
Interestingly, one of my other cells (different size and brand of battery) was not visually affected after being fully charged for months.
From now on though I try to use my charger to put my new LiPOs at storage charge.
Does the “expanding” or “ballooning” happen to cylindrical cells too when left charged or is that just a LiPO pouch battery problem?
How accurate is your crystal ball?
My theory is that things go pear shaped without notice, I want as many amp hours available as I can. If I DO get a warning, for instance, an oncoming storm, I can get the bin out and refresh as many cells as I have time for.
This doesn’t sounds like what someone named “lazy-r-us” would do…
Au contraire, my friend! Way easier to do it this way than constantly remember to keep track of the cells!
I try to only use cells “actively”, in lights that I actively use for one reason or another. So I keep very few “extra” cells on-hand.
All the rest, those aforementioned “extra” cells, I leave untouched from the factory. I’m presuming that they’re properly charged to ~40% or so.
It’s also why I don’t hoard Li cells. By the time I use up these in “active rotation”, the others would likely be moribund anyway.
Oh yeah, so it’s guesswork and presuming they’re properly charged to 40% or so.
F —> they vary in charge when stored 
I usually know which batteries are charged and which arent, i keep them in different boxes to distinguish the charged from the uncharged.
i have charged 4 30q bt’s which i purchased for the Q8, just to try my new Li500.
another set flattops which i solder blobbed/boobed are still never charged, they contain their original charge.
for the rest, as i said, i keep them in different boxes to distinct the charged from the uncharged
I charge a bunch of them and put them in plastic 4x 18650 boxes
And when they’re discharged (usually around 3.3 Volts) i put them upside down in the battery boxes.
Then when they’re all used up, or just before they’re all used up, i charge a bunch of them again.
I keep in mind not to let them sit in a box fully charged for too long.
I am thinking to buy HPAC specially for my battery.
After that I can make colocation data center at home. :money_mouth_face:
I know your not supposed to, but I typically store mine charged in plastic cases designed for that size cell. If I had a charger that would do a storage charge, I would use that. I have a few cells, 18500s and 16340s, that I have nothing to use in right now.
I “store” mine at 75%. Low enough to improve the lifespan of the cell while still allowing for a decent usable capacity if I need it right away. Room temp, which can hit 80F where I live.
What is that?
What happens when you keep a lithium-ion battery fully-charged all the time:
This was not an isolated incident. The entire test lab had similar problems, multiple phone models from multiple manufacturers, because they were constantly plugged in and the charge kept oscillating between ~95% and 100% as the devices went through automatic top-off cycles. The pattern at the right of this graph was basically repeated nonstop whenever the devices were plugged in, which was all the time in a test lab environment:
The inflated battery shown earlier is what would happen pretty consistently after about 6 to 18 months of being plugged in, even if it was idle most of the time. At about 18 months, no devices were functional any more. However, an extra which was stored half-full with the power off … was still nearly as good as new.
Cylindrical cells don’t tend to balloon like that, due to the outer shell being strong, but they still lose capacity and build up pressure.
Keeping li-ion cells full in storage, and topping them off frequently, is one of the most effective ways to kill them faster.
:+1: thanks 
Same here…I don’t have any extra LiIon cells. When I’m going hiking, boating, camping, whatever for a while, regular light gets a top up so it’s good to go for the “event”, and it gets used a fair bit. I have 2 x 18650 cells for flashlights and one is always in the truck, and one is at home by the bed - both get used regularly and I swap the batteries around when charging as the one in the truck is used a bit more frequently. This helps to keep the cells at similar capacities. If one fails, I’d just order another protected 18650 cell.
For NiMH which can be stored fully charged, I have a lots of spares and I rotate them through remotes, clocks, small flashlights for backup and around the house activities, etc. These I top up and store in a room temperature drawer till they get swapped out, which is fairly often for remotes. I make sure to rotate them when charging too.
I didn’t vote in the poll as there is no option for “I don’t store them, I use them”.
I had two nimh packs which I left charged (without using) for a year or two, they died completely.
Won’t hold any capacity, and produce very little voltage.
rip
Should have cycled them every few months I guess.
And yeah you’re right, if you just use batteries without storing then the poll doesn’t really apply to you 
+ 1 in my opinion. Being through the east eye wall of Katrina. I’ve gotten to wear I horde batteries now. All the pulls I can find. Usually anything 1200+ Ill keep and fully charged. Just for hurricane preparedness. Like you said if there’s warning I’ll top them all off for whatever self discjarge occoured. Used and free not really concerned if they loose some life at full charge.
Edit, my good cells I use in my flashlights get rotated about every 4-6 weeks. I’ll put them in a powerbank and use them. But all the extra free pulls over the last 6 months of recycle bin pulling stay fully charged. But my opus only charged to 4.13 so I guess its not really maxed topped off. Usually settle to around 4.1
Fully charged, boxed and in the fridge.
I stopped using protected cells because there’s always a small parasitic drain from the protection circuit. The only cells I had actually croke dead from disuse were protected. I still have the 2 original protected panny-Bs, but I keep them in my regular-use lights (EDC and headlamp).
The other lights are more or less special-purpose, but still somewhat regular use. C8 for yard-snooping, VG10 for non-EDC general-purpose use, etc. The other unprotected panny-Bs and 30Qs, and some powerbank pulls, I keep shelved at less-than-topped-up levels.
Only in case of a big storm coming, high winds, etc., will I grab all the in-light cells and top them off. Worst case, I can always top up cells when needed from inside the car.
Old NiMH batteries tend to die anyway. They basically had to be re-conditioned on a regular and frequent schedule.
Newer “LSD” NiMH is much better at remaining useful for years and years, and doesn’t require much maintenance or special care. It’s still a good idea to fully charge and fully discharge them though.
Li-ion is different than either of the above, since it doesn’t like being fully charged and really doesn’t like being fully discharged. It’s happiest right in the middle.