I have some batteries that i keep for emergency use or the rare necessity, and they will last longer if kept below 10ºC (40F), but its a basement room with relatively high humidity, is it a good idea to store them there or will the high humidity (dampness) damage them over time?
Put them in a sealable bag possbly along with a desicant aswel. That willgive you the benifits of longer storage, and non of the risk for damage
What kind of batteries are we talking about here. And for how long?
li ion 18650 and 26650, 6 months to a year i would guess (but lets say for the life of the battery for long term planning purposes)
Don’t store them fully charged.
i know, they are 40-50% charged, i don’t use them much so until the current older ones die or i need several backups on a long trip or an emergency i want to keep these as long as i can
I think the standard cool, dry place rule applies.
Place them in a sealable sandwich bag with dessiccant as mentioned above.
Also I have a lot of batteries for emergency use. I keep it charged, because, in emergency, discharges are useless. I keep them in the refrigerator, closed in an airtight box, together with a bag of rice to absorb the moisture.
I do the same, because losing 6% capacity per year is much better than having lots of discharged useless cells during an emergency.
True enough, i keep my everyday batteries fully charged since they were laptop pulls (and i have more of them), but i seldom use my full capacity holding batteries i bought from fasttech so i figure i should keep them cool for longer life for when i do need them, and can fully charge if needed
thanks for all of your reply which help me in this confusion.
Thats my line of thinking as well, if they are for emergency use:
- You can never predict situations you’d need charged batteries for. “We need to search for x in the dark/The power’s out, I need light/I need backup phone power for my trip/Mr. X (or animal) didn’t come back we need to go look for him/One more person showed up for the night hike, lets go night hiking/I got busy the last two days and didnt charge batteries after I used my light for 2hrs the other night and I want to go out again/Something went bump in the night, here hold this light while I go check” cant be prefaced with “I’ll charge these emergency batteries this time for 4-8hrs.”
- It takes a couple years for the 6% reduction buildup to become noticeable, and I’m sure I’ll want new batteries by 3, almost definitely by 5 years.
- Supposedly, after 5+ years, non-new Li-ion batteries aren’t really reliable/usable anyways. So unless you are going to just collect the batteries from the mail and put them in cold storage for BACKUP emergency (or zombie apocalypse) without charging/testing/using them, it doesnt really matter.
If you really need to store them fully charged, then you should do so in a cool place or they take ~20% permanent damage every year ( BU-808: How to Prolong Lithium-based Batteries - Battery University ). But humidity is bad for the batteries too so you should make some container that protects the batteries from it.
It would be best to keep some CR123’s stored for emergency use, and keep 18650’s only for daily use (if the light accept both of them).
Hearing how other people protect their batteries from moisture would be interesting… or do you think something like zip bag is good enough?
It's common knowledge that lithiums kept at 0 degrees celsius will keep the their charge better than higher temp.
Here's the other thing. I've experienced using cordless power tools using lithiums in cold temps (negative 5 to 10 degrees celsius) and witnessed reduced capacity in those type of environments. This is also common knowledge in the construction industry or is it just a myth and in my head?
So the question is, what's the maximum coldness we can keep / use these batteries.
I guess the fridge will be fine but probably not the freezer, huh?
Cold (and 40% charge!) is only good for storing lithium batteries for longer times to prevent damage. When using them, cold is not a good thing. You get only reduced amount of current (mAh) out of them in cold environment. So it’s not a myth or just in your head. If those tools are used daily, they would be best kept in warm place.
Suggests that the cold usage limit for Lithiums vary from –20C to –40C. Colder weather = less current out of the battery.
Agree, there are anti humidity bags or box available.