Did I kill my 18650 battery, was it a dud, other?

[johnnytwofingers]

I just got a brand new pair of 18650 Trust Fire Protected Li-ion 3.7V 3000mAh batteries.

Trust Fire 3.7V protected 3000mAh rechargeable Lithium Ion battery 18650 with PCB.

I charged them both up and put them into a Silver Bullet that I bought used. Neither of them would fire (with any atty I attached). After some searching around I found I was likely dealing with the centre connector on the mod being pushed to far down, so I tried pulling that up, and retrying to fire, but still no luck.

During this process I did notice one of them was slightly warm on the bottom when I took it out. I'm 99% certain I was running the PV with a short (due to the centre connector touching the side threads) for some of this process.

So, I finally worked that issue out, and one of my batteries will fire, but the other one will not. When I put both batteries into my Trustfire TR-001 charger, the lights stay green, seemingly indicating they are fully charged. If I check the voltage with a multimeter however, one battery reads 4.18 volts, but the other one reads 2.60 volts.

Could I have permanently damaged the battery that reads 2.6 volts, or could it possibly have been a dud right out of the wrapping? Is there any way to determine (perhaps a superior charger would help) what the exact problem is?

This article:
http://www.lygte-info.dk/info/battery%20protection%20UK.html
...seems to suggest there is a circuit that can permanently disable a protected battery: (CID or pressure valve, will disable the cell permanently if the pressure is to high in the cell (Can be due to over charge). )

However, if I had triggered that, then I wouldn't expect to get a reading of 2.6 Volts out of it.

Also, it says these batteries have PCB:
PCB will protect against over discharge, over charge and over current, depending on design the PCB will reset automatic or when placed in a charger.

So theoretically at least that circuit should have prevented permanent damage.

 

[cskent]

I have a regulated vv boxmod that I use sometimes. If I run it until it quits vaping my batteries will read 2.5v, and if I put them in my TR 001 charger the light stays green. My guess is that there's a voltage detection circuit that won't allow it to charge batteries if the voltage is too low, probably to keep people from trying to charge the wrong type of battery in it. If I put the same batteries in my cheapo backup charger they'll charge just fine. I guess I'm not offering advice, just sharing my experience.

 

[Switched]

@ 2.6V it is gone to sleep, a permanent sleep

 

[johnnytwofingers]

@ 2.6V it is gone to sleep, a permanent sleep

I've heard this term "go to sleep", is there a well known site I could read to educate myself more on the topic?

 

[studiovap]

@ 2.6V it is gone to sleep, a permanent sleep

Why do I feel sad about this battery, It's like a friend has been lost LOL

 

[Ictinike]

I've heard this term "go to sleep", is there a well known site I could read to educate myself more on the topic?

Here is an article and there is hardware that can 'boost' them back past the cut off point but use caution.

How to Awaken Sleeping Li-ion - Battery University

Li-ion batteries contain a protection circuit that shields the battery against abuse. This important safeguard has the disadvantage of turning the battery off if over-discharged, and storing a discharged battery for any length of time can do this. The self-discharge during storage gradually lowers the voltage of a battery that is already discharged; the protection circuit will eventually cut off between 2.20 and 2.90V/cell.

 

[Switched]

I've heard this term "go to sleep", is there a well known site I could read to educate myself more on the topic?

Ictinike provided the link. As can be read it is not something done by the avg layman

 

[johnnytwofingers]

Ictinike provided the link. As can be read it is not something done by the avg layman

Agreed, into the bin with it. Thanks for all the comments.

 

[Ictinike]

Ictinike provided the link. As can be read it is not something done by the avg layman

Agreed.. I wish they had some fool proof/safe way for an avg user to do this. I guess the old saying about an ounce of prevention, yadda yadda Take care not to let them fall into this range on normal use and you should, "should" be ok..

Agreed, into the bin with it. Thanks for all the comments.

Hehe yeah it's one for the memory banks. I pulled that link from my bookmarks off this site as I vaulted it for info/future use later. Sorry if your bat(s) are into this range and maybe you could find someone local who would properly boost them or try to boost them out of sleep mode. It really is a protection mechanism and I agree with it but I think sometimes it happens far to early and/or without warning. Good Luck!

 

[Switched]

... just re-read the OP. It seems the PCB on that battery did not act in time or at all to prevent you from vaping below the LVT (low voltage threshold or cut off), generally 2.8V. If this is the case, I would not feel safe using a battery with a questionable PCB, regardless if i could awaken it or not.

 

[WillyB]

... If I run it until it quits vaping my batteries will read 2.5v, and if I put them in my TR 001 charger the light stays green. My guess is that there's a voltage detection circuit that won't allow it to charge batteries if the voltage is too low, probably to keep people from trying to charge the wrong type of battery in it. If I put the same batteries in my cheapo backup charger they'll charge just fine.

Not only "cheapo" chargers, but the better chargers will also charge them.

A battery with a tripped protection circuit will read zero volts, but many times as it 'rests' the voltage creeps up enough to reset it. Many of the better chargers can reset the PCM by tickling it a bit.

A charger like the popular TR-001 has a low voltage threshold, as you noted, where it won't turn on period.

Notes on the Xtar WP2 II.

Measurements charger

Below 2 volt the charger charges with about 0.5 mA, this is enough to reset a protection pcb (Note: The led is green).
Between 2 volt and 3 volt the charger charges with about 80 mA.
Between 3 and 4.15 volt the charger is applying regular charge current (See curve below).

Basically even at a zero volt reading these chargers still provide a small amount of current once turned on.

As far as 2.5V being too low, both AW and Panasonic have batteries whose mAh has been calculated based on a 2.5V cut-off.