Reconditioning Rechargeable Batteries

LED User

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I have two of four Tenergy 18650 3.7v Li-Ion batteries that won't begin to recharge using my OPUS BT-C3100. In fact the charger doesn't even recognize the batteries are in the charging slots.
Are these batteries dead beyond being brought back?
This charger has a discharge function. But it looks like they are already discharged beyond recognition.
Thoughts?
 

Monocrom

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I have two of four Tenergy 18650 3.7v Li-Ion batteries that won't begin to recharge using my OPUS BT-C3100. In fact the charger doesn't even recognize the batteries are in the charging slots.
Are these batteries dead beyond being brought back?
This charger has a discharge function. But it looks like they are already discharged beyond recognition.
Thoughts?
Try a different charger. If the batteries still won't behave properly when on the other charger, replace those batteries and dispose of them properly, as well as immediately! I don't take any chances with those types of rechargeable batteries. Not worth it. Made a thread awhile back regarding a beloved Klarus light that burned out its own LED but somehow kept putting out light. Just with an ugly black donut hole in the center. Also noticed that the light heated up on Turbo mode far faster than normal. Immediately turned off the light. Yanked that battery out of there! Got it far away from me. Properly disposed of it later.

I'm not looking for any sort of vent with flame incident. Those types of rechargeable batteries are supposed to behave a certain way when they are on a charger. A certain way when being used in a flashlight. A certain way when sitting idle in a flashlight. Any sort of deviation in expected behavior should be dealt with, immediately! Quickly check and analyze the situation, determine the problem, implement the proper solution.

Can't determine the problem? Get rid of them! Done! Not worth trying to recondition them or do anything else with them but properly dispose of them. They're not dangerous.... But they are potentially dangerous when they start acting up. When they behave in any sort of way that is out of normal behavior for them. Yes, I know just how expensive these types of cells are. I definitely know. But if they vent with flame or explode, and you accidentally breath in the toxic fumes they give off.... It's going to cost you a helluva lot more than just the cost of replacing those two cells. I'm sure others will disagree with me. But I watch my cells like a hawk for even the tiniest bit of abnormal behavior. And, take a zero tolerance approach to such cells when they do behave differently than they are supposed to.
 

LED User

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Thanks Monocrom, I remember your post. And I appreciate your advice. Better safe than sorry.
I thought the issues were with rechargeable CR123's used multiply.
My charger works fine on my other rechargeables, so its definitely the batteries.
In another thread I saw the photos of someone's patio.
I'll dispose of them now, ...cheap insurance.
 

Monocrom

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It's an issue that unfortunately can definitely happen with all types of rechargeable lithium-ion batteries. You're absolutely doing the right thing.
 

ChrisGarrett

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Batteries, much like gun barrels, are consumables and will eventually wear out.

Get new ones and recycle the old ones.

There's really no such thing as 'reconditioning' them.

Chris
 

MyUsernameTX

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I've also tried reconditioning 18650's in my Opus charger, and never had any luck. Tried on a cell 3 times and then realized I'm wasting a good amount of hours to try get an old cell back to being good, when a BRAND NEW high quality cell is just $6


Its possible the protection circuit (Assuming its protected?) is bad also. I've had quite a few protected cells kill themselves
 

IMA SOL MAN

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I've also tried reconditioning 18650's in my Opus charger, and never had any luck. Tried on a cell 3 times and then realized I'm wasting a good amount of hours to try get an old cell back to being good, when a BRAND NEW high quality cell is just $6


Its possible the protection circuit (Assuming its protected?) is bad also. I've had quite a few protected cells kill themselves
Yeah, you really have to balance the worth of your time against the cost of a new cell.
 
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