14500 batteries -leaving unused

[Bunk3r]

in my quest for a new flashilight i am tempted by one that uses 14500 batteries, i dont mind buying the batteries and charger, but i dont know if they will suit my application, because i want a torch that will sometimes get heavy use, but sometimes will sit unused for 6 months. with rechargeable 14500 cells will this be a problem? -ie if i pick up the torch after not using it for 6 month will the batteries still have their charge remaining?

 

[DM51]

in my quest for a new flashilight i am tempted by one that uses 14500 batteries, i dont mind buying the batteries and charger, but i dont know if they will suit my application, because i want a torch that will sometimes get heavy use, but sometimes will sit unused for 6 months. with rechargeable 14500 cells will this be a problem? -ie if i pick up the torch after not using it for 6 month will the batteries still have their charge remaining?

It will be perfectly OK, but it is not recommended that you store Li-Ion cells at full charge for long periods. A good guide is to store them at no more than 4.0v (80%). You will see very little loss over 6 months, certainly less than 5%, provided the storage temperature and other conditions are OK. If you store them at the full 4.2v (100%) charge, you will still see very little loss, but this will reduce the life of the cells.

You should bear in mind that some flashlights consume a small amount of power even when switched off and at rest. This is normally negligible, but over a long period it can be significant and could deplete a cell.

 

[Bunk3r]

^ has anybody got any numbers to go with that because the batteries will be stored at full charge for some time, so how long can they be stored? and how much does it damage the cell?

if the light is been left for a long time it is likely that it will be left with the batteries out, but i want to be able to put them in and go. maybe i should just stick with AA's.

 

[DM51]

What numbers are you looking for? The self-discharge will be <5% over 6 months. Maybe only 2%. That is hardly noticeable. If you store the cells at 4.0v / 80%, you can expect a reasonable life out of them. If you store tham at 4.2v / 100%, their life will be reduced.

 

[Bunk3r]

What numbers are you looking for? T....... If you store tham at 4.2v / 100%, their life will be reduced.

how much will their lifetime e reduced by?

 

[DM51]

Maybe 30%. Li-Ions have an advertised life of 2-3 years, so that might go down to ~18 months, or maybe less. It depends on what you do with them afterwards. There was a report that someone stored some Li-ions at 90% (4.1v) for a year, and they lost only 3% capacity in that time. But that is probably unusual.

If you want long storage time, why don't you consider Lithium primaries as a power source? They have a shelf-life of 10 years.

 

[Bunk3r]

thanks for the info. Ive pretty much decided rechargeables arent for me right now. -if i start using my flashlight more then i will reconsider. Lithium primaries do indeed look good and might just be the cell for me.

 

[lowatts]

FWIW, I have a couple of Panasonic LI-Ion battery packs from 2001 for a Panasonic digicam. I almost never use them, maybe recharged them 2 or 3 times in all that time. I just tried them again a few months ago after not having used them for at least 3 or 4 years and really didn't expect them to be still much good. But these quality cells still seemed to have close to their original capacity after recharge, though before the recharge they were too weak to power up the digicam.

 

[DM51]

FWIW, I have a couple of Panasonic LI-Ion battery packs from 2001 for a Panasonic digicam. I almost never use them, maybe recharged them 2 or 3 times in all that time. I just tried them again a few months ago after not having used them for at least 3 or 4 years and really didn't expect them to be still much good. But these quality cells still seemed to have close to their original capacity after recharge, though before the recharge they were too weak to power up the digicam.

That is interesting. Were they left discharged for 3-4 years, or were they fully charged beforehand? If they were fully charged when stored, it sounds as though they lost all their charge during storage, which for that length of time is not surprising. And how did you actually measure the capacity after the storage period? Sorry for the questions, but I would be very interested to know, if you have time to answer.

 

[lowatts]

They were charged before storage IIR. I did't know it was harmful to store at full change, actually thought it was harmful to let them go empty. I bought the digicam for a trip, don't usually do video recording, that's why it was out of sight and out of mind for so long. Kinda wish I didn't spend the cash on the kit actually...

Anyways, I had a need for it recently and pulled it out of the closet. The batteries seemed to drain at about the same rate as when I used them years ago. Not too scientific I know, but whatever lost in capacity isn't really obvious.

I think keeping these batteries frequently charged, as in leaving them in laptop computers that run off the AC anyways, kill them much more quickly. I support PCs and see that after two or three years the Li-Ion packs easily loose half to most of their capacity even when they've only had under 30 cycles (some laptops show battery history recorded in their electronics). One of my own work laptops that had under ten cycles had it's battery life down to maybe 10 or 20 percent after three years. So it seems to me if unused quality Li-Ions are stored in a cool dry place and with no frequent top-offs, they can last pretty long.

 

[cave dave]

Why 14500? Why not RCR123 light? The 123 light is likely to be smaller, the same diameter and the RCR capacities about the same, plus you will be able to use 3.0v primaries as well. A 14500 cell light will likely only work with that cell, an AA will fit but won't power the light.

 

[DM51]

They were charged before storage IIR. I did't know it was harmful to store at full change, actually thought it was harmful to let them go empty. I bought the digicam for a trip, don't usually do video recording, that's why it was out of sight and out of mind for so long. Kinda wish I didn't spend the cash on the kit actually...

I know the feeling!

Anyways, I had a need for it recently and pulled it out of the closet. The batteries seemed to drain at about the same rate as when I used them years ago. Not too scientific I know, but whatever lost in capacity isn't really obvious.

So over a period of 3-4 years they completely self-discharged, which is what could have been expected. The interesting thing is that you have not noticed a reduction in performance. If you can remember how long they used to last before, and how long they last now, this would give a guide to how much capacity they have lost. There will have been some loss - it would just be interesting to know how much.

I think keeping these batteries frequently charged, as in leaving them in laptop computers that run off the AC anyways, kill them much more quickly.

If you are not using them, then keeping them continually charged is certainly not a good idea. But if you are using them frequently, it is better to recharge them before they run right down and hit the protection cut-off.

I support PCs and see that after two or three years the Li-Ion packs easily loose half to most of their capacity even when they've only had under 30 cycles (some laptops show battery history recorded in their electronics). One of my own work laptops that had under ten cycles had it's battery life down to maybe 10 or 20 percent after three years. So it seems to me if unused quality Li-Ions are stored in a cool dry place and with no frequent top-offs, they can last pretty long.

Li-Ions only have a life of ~3 years anyway, so a reduction in performance after that time is to be expected.

Why 14500? Why not RCR123 light? The 123 light is likely to be smaller, the same diameter and the RCR capacities about the same, plus you will be able to use 3.0v primaries as well.

Not really. You can't interchange R123s and CR123As because of the voltage difference. However, 2 x 18500 Li-Ions = 3 x CR123A primaries in a 3-cell (10cm) light, and with a 9v LA these are completely interchangeable so this size is therefore a very versatile choice. But it looks like the OP will be better off using Lithium primaries anyway.

 

[Bunk3r]

Why 14500? Why not RCR123 light? The 123 light is likely to be smaller, the same diameter and the RCR capacities about the same, plus you will be able to use 3.0v primaries as well. A 14500 cell light will likely only work with that cell, an AA will fit but won't power the light.

the reason for the questions on the 14500 was because of this deal: https://www.kaidomain.com/WEBUI/ProductDetail.aspx?TranID=2311 . I am now looking at a light that runs off cr123's but has an extender tube so i can run 2AA's when i dont have a cr123a to hand, but i have a seperate thread about my choice of flashlight here: http://www.candlepowerforums.com/vb/showthread.php?t=167482

my battery questions have been answered.