How do you store your batteries?

No special voltage for storage, some fully charged, some fully depleted. Have a couple of hundred lithium ion batteries and in 8 years or so have only had 2 or 3 batteries go bad, this is including 8 year old batteries. Storage voltage level is overrated.

I agree on this, I keep extra batteries for emergencies. Whenever I would need it I know its fully charged. That’s the reason I bought a lot of 18650 for power outage in an inevitable time.

I try to keep mine stored at 3.6V to 3.7V. Of course the few I use, I fully charge. I recently found a Panasonic 18650B in a light that used to have 3300mAh when I first got it. It now only has a capacity of around 2800mAh. It was sitting fully charged for about 2 years. BTW, as a fully charged cell self discharges, the stress on the cell is relieved somewhat as the voltage declines. Even though, it harms the cell. Imagine how much more harm is done when cells are left constantly charging in laptops that are plugged in. Those cells see tremendous stress as they are constantly topped off and receive more stress with no relief.
Then think of the even more stress that GPS units receive stuck to the windshield of a car in the hot sun. In fact that combined with the black case many of them have, leads to an early death. The only GPS units I have that still have working cells are the ones with white cases.
I was greatly encouraged when I opened up a brand new, unused GPS receiver that I had purchased in 2006. Before I turned it on I opened it up and checked the voltage on the included Li-ion cell. Even though it was 10 years old, it was sitting at around 3.5V. I charged it up and did a capacity check with my OPUS. I don’t remember the exact number but it tested out to around 95% of capacity. Also the GPS had a run time of about 3 hours, it’s stated runtime, and that too confirmed that Li-ion cells do very well stored at half capacity, even the ones manufactured 10 years ago. I can only assume they are even better now.

I don’t really “store” cells… even though i have a small metal suit case with between one and half dozen spare of each size - probably more 18650 though, in appropriate plastic cases. Those are ‘new’ or not yet used except for a few i happen to use in a rotation - but i usually don’t put them in this ‘bin’; i tend to keep them close to the device they are used in.

The big chunk of my cells are ‘stored’ in flashlights (totally lost count since i joined BLF), hopefully fully charged. Most i don’t use much, and when i happen to use one, i usually top off the cell right away before putting the light back in it’s place.

I understand that Li-ion batteries will last longer if treated just right… but i’d rather have cells ready to use that will decline faster then cells i can’t use right away if i need them, but that will last longer. During the past four years i’ve used them, li-ion cells have evolved faster then their obsolescence rate so that you probably want to renew them for increased capacity and/or amps.

I store half of my LiIon cells at 3.7 volts. The rest are fully charged. My shelf queens have no batteries installed. But the rest, 20 plus, have fully charged batteries installed and ready to go. In an emergency, I have 5 portable USB chargers, plus 4 UPS’s with USB outputs, and a generator if things get really bad.

A great comment ToyKeeper, and very good advice. I long ago, quit plugging in my cell phones overnight to charge, for just this reason. When doing so, and if the phone is left on. The charger will bump the battery back up to 100%, about 5 times a night. Not good at all, for long term battery life.

I tracked and charted this, via an App on my phone at the time.

I tell people this, and many of them think I’m crazy. Oh well, I tell myself . . . They will live and learn. Hopefully. :sunglasses:

I used to make and keep log records for my 18650 cells. Lots of columns. Lots of notes. But I started to have to have more important stuff to do such as needing to deal with other peoples unresolved alanon issues. So all of this went by the wayside. Now, I rotate my cells as best as memory allows.

“…In My Green Metal Suit I’m Preparing To Shoot Up The City
and the ring at tthe end of my nose makes me look rather pretty…”

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Each one of my lights have their own cells and they are always fully charged and ready to go. I have a rotation set up for my trail lights and my EDC lights.At the longest they may be idle for about a week.

I guess it would be economically more feasible to have sets of cells used in “like lights”. I have never done that.

So if the power went out for a month, I would have no problem with navigating inside or outside in the dark.

As far as my cells[extra] that are stored. I keep them ~ 3.60v and they are stored at room temperature in the plastic cases that most manufacturers/dealers give us when we purchase them.

plugged in 24/7 for MONTHS?

hmmm, thats what I do with my laptop

wow, good info!

So, charging a LiIon ONCE between uses, putting it in a case and carrying it as a spare, and NOT topping off the charge, 5x nightly, for 6-18 months, is fine?:wink:

I’d have to find the numbers again, but I’ve heard that a li-ion cell stored fully-charged will permanently lose something like 20% of its capacity after a year of storage, compared to like 1% or 2% if stored half-full.

So… it doesn’t inflate and destroy the battery, but it’s not particularly healthy either.

[quote=ToyKeeper]

permanently… wow
thanks for the education

Let’s see… this has lots of interesting info.

ToyKeeper is very on track. Did you read BU-808? That's not a joke. The li-ion battery industry has a lot to benefit from charging cells up to their maximum specced voltage and letting them sleep/operate at or close to those levels: both capacity claims and overall sales increase.

3.92/4.2 of maximum voltage for removal of all voltage related stresses.

The longer a cell is kept at high voltage, the more it degrades.

Modern li-ion cells keep above ⅔ of their specced maximum energy at the aforementioned “no voltage stress” value. Thus, keeping cells within this maximum lifespan window really pays off, and no major energy loss after a year vs a fully charged set because of its accumulated damage.

Of course, believe as you wish (and deal with the consecuences).

how about a portfolio.

me, worst cells fully charged ready to go.

best cells half charge room temp

extra very good laptop pulls half charge freezer.

When the charger indicates 40-50%, I stop and store most of my cells at room temperature. The exception is my EDC’s and commonly-used lights; the cells I use for those are fully charged. I have two 18650 lights in the workvan and one spare cell. Those cells serve no other duty. I rotate them from most-used to spare and from spare to least used than around again every couple months so that none gets charged but not used. I have one 18650 house light that gets it’s own fully charged cell.

Not the best technique for storage, but this gives me the light I need when I need it and it allows me time to charge more cells if need be. “Specialty” lights get cells charged for use only when they are needed, and multi-cell lights each have their own matched sets of cells.

When someone comes up with storage-friendly LiIon’s I’ll be the first to buy :smiley:

Phil

All my lithium ion batteries (14 total) are in constant use. 2 of my flashlights have a back-up battery that I just swap and charge when the battery gets low. With the other flashlights, I recharge them when the batteries get low.

My last two TrustFire IMR14500 700mAh (red-gold) are now stored inside my old hair clipper. From 2S Ni-MH to high current li-ions. Performance? Staggering!!!

Originally posted on Sat, 06/24/2017 - 07:28; video problem fix.

For when you clip your old hair?

Btw, video’s unavailable. :stuck_out_tongue:

Video works as far as I can tell.

Well, a day ago plus a little while a friend of mine came home and we went to party at night at the capital (). Pretty ladies out there agreed I look younger than my 41+ solar cycles.

I posted the message while having a Dutch Piss at the bar.

We came back home at ≈12:15PM ROFL!

P.S.: the Ultrafire AT-01 is a PoS.

Might be a region thing, no idea. Just get the “static” display with small-text “This video is unavailable.”.

Fooey. Still didn’t get mine yet.

What sucks about it?