Any way to rejuvenate li ion cells?

Hi gang!

I bought a couple of king kongs about 18 months ago and they have not seen much use, maybe about 4 recharges in that time. Last night when I used them, I noticed that their capacity was greatly reduced :frowning: probably because at least once the may have over discharged….

Any way to ‘kick’ a bit more life into them, or is it time to get some new cells (and look after them a bit better this time)?

Cheers

Haven’t you heared of the fountain of youth? It’s probably best if you get a pair of new ones :slight_smile:

Rejuvenation potion of course. :slight_smile:

I recall reading that li-ion cells degrade fairly fast even when never used — and that three years is about what you can count on for them.

It was a warning that buying old stock cheap isn’t smart for this chemistry.

Seriously, don’t mess with trying the sort of ‘rejuvenation’ that’s sometimes talked about with NiCD or NiMH cells, which aims at zapping them to remove crystals that grow slowly inside. With li-ion, well, you know what could happen.

(And if you don’t know what could go wrong, don’t be using li-ions)

I’ve yet to hear of any such for li-ion. Don’t think it’s possible in this chemistry. That being said I don’t know the exact mechanism by which li-ion capacity decreases.

Ehh… I have a Sony camcorder with 7 year old battery pack that still holds close to original charge.
Had been lying on the shelf completely unused for past 2-3 years, though.

You need to balance your negative and positive thoughts.

try to cycle them few times, like 5-7 charge \discharge , no garrantee it will help, but it worth a try.

They are on charge atm, but I’m being a bit paranoid and keep checking for heat…

Time to buy some replacements…

Was the voltage of the battery ever below 2.7vdc for an extended period

For batteries that have sat idle for some time, cycling them 2-3x full charge, full discharge can perk them up, but if they are no longer holding a charge (or seem to be reduced charge) there more than likely isn’t anything that can be done

Yes, I think that this was the problem. For a few months the cells were left discharged, neglected and forgotten about…

Tried the recharge cycling a few times, but feel that I’m just flogging a dead horse. Just seems such a waste of hard earned though, to throw them away after such little use :frowning:

I'm positive you're right on this matter..

Do not know why but old Nokia Li-ion batteries seems to have a long life.
Phone in my pocket was bought in –08 or –09 and used since.

i’m neutral on this subject, so that means i have successfully balanced my thoughts?

You got it! I wish I wasn't so imbalanced. But then again, I'm old and set in my ways.... Maybe I'll hook up my car battery charger to my ears and hopefully things will balance out! What do you think??

To set the video recorder post the results!

I saw a youtube video of a guy who replaced his car battery with 6 capacitors wired in series, perhaps that is worth trying instead of your car battery?

Lick those caps to test its state of charge first.

Eh… at 3V each, nothing bad could happen :stuck_out_tongue:

Cycling 3.0-3.3 to 4.2V a couple of times would be the most I would push these cells.

They’re already probably permanently damaged.