Problem with Wolf Eyes 18650

[F_P_R]

Hello everybody,
i got probs with two WE LRB-168A (18650) cells and a WE CH-02 charger.

First thing: The cells came out the charger around 3.9 V

Second thing: I run the cells in a Thrunite Catapult together.
After about 90 mins the light blinks short, than turns off. I think the runtime is OK.Then i checked the voltage and one cell has only 2 volts.

I checked this twice. It's always the same cell that has only 2 V left.
Is this cell or the protection circuit broken? Im afraid this cell might go

Why are the cells freshly charged only 3.9 V?

I hope somone can helpme with this. :shrug:
Greetings

 

[how2]

Which cell has 2V. The one near the head or near the tail.

Try swapping them around and see if you get the same results.

 

[old4570]

Mark the cell ... So you dont mix it with the good ones ...

Can you go without the bad cell ? Or is it the same location in the flashlight that gives this result ?

Run the battery down . and safely discard .
Its not worth the risk if it has been damaged .

Its the in-balance in charge state that causes problems , so if one is out of whack , dont use it .. As to why ? Its not right , and that would be enough for me to toss it .

 

[F_P_R]

Thanks for the answers!
OK i test the cells and swap them but this will take a while.

Both cells came out the charger at 3.9 v.
What can be the issu?

Greetings

 

[old4570]

If there both coming out of the charger @ 3.9

It could be increased resistance in the battery , or the charger itself ..

Try running the batteries for maybe a few minutes and throw them back in the charger and see if they top out higher ..

Ive found some new batteries will top out @ 4.18 , but after a short run and then back to the charger , they go 4.2v ..

If the batteries have been over discharged , they could be damaged and simply wont accept more ...

Hard to say ... Without more testing / data

 

[F_P_R]

I did some more testing:

I tried another charger so the cells came out on 4.18v. Thats OK.

I swaped the cells in the Catapult.
Now the other cell has only 2 v left.
The cell that has the 2v is always near the head.
Is this a problem of the Catapult?

:sigh:

 

[hazna]

whats the voltage of the other cell? And what is the voltage like when you have rested it?

 

[old4570]

Looks like the forward cell is being worked hard , looks like something you will have to work around , like swapping the cells around possibly , or charging earlier . You dont want the battery going on you .

 

[F_P_R]

@ hazna
The other cell has 3.6v

 

[mdocod]

From 0V-3.6V is about the bottom 10% of the available capacity in a LiCo cell. Having one cell discharged to 3.6V with another cell at 2V means that they have discharged within 5-10% of eachother. Running these cells down below 3V should be avoided if you can help it.

----

Hypothesis:
When a flashlight is run continuously, the head of the flashlight warms up, the cell in front (closest to the head) is going to be warmer than the rearward cell. Heat energy directly effects the level of chemical excitement in the cell. A higher state of chemical activity will result in the cell holding a higher voltage under the load presented for the majority of the run, which leads to the cell being depleted first.

I would imagine that if the flashlight were used in short bursts rather than marathon style runs, the variation in discharge between the cells would be less intense.

------


Off Topic:

Wolf-Eyes chargers use the protection circuit in the cell to terminate the charge. (Normally). They charge at a relatively high current until the charging voltage reaches ~4.35V at which point the PCB acts as the cut-off point. This charging method results in . If the cells are coming off the WE charger at 3.9V, then there are many possible reasons but most likely, there is something wrong with the charger, also possibly, something wrong with the PCB or the cell health. My personal recomendation is to avoid using Wolf-Eyes chargers where-ever possible. They can present a real danger if a PCB fails or if they are accidentally used to charge unprotected cells.

Eric

[edit in] It is interesting that the cells are being allowed by the PCB to go all the way down to ~2V after the load is removed (this means that the cel voltage probably went down to ~1.5V or less under a load). This suggests to me that the PCB is not functioning properly, might have something to do with the 3.9V termination when on the WE charger. hard to say though.

 

[aim54x]

Off Topic:

Wolf-Eyes chargers use the protection circuit in the cell to terminate the charge. (Normally). They charge at a relatively high current until the charging voltage reaches ~4.35V at which point the PCB acts as the cut-off point. This charging method results in . If the cells are coming off the WE charger at 3.9V, then there are many possible reasons but most likely, there is something wrong with the charger, also possibly, something wrong with the PCB or the cell health. My personal recomendation is to avoid using Wolf-Eyes chargers where-ever possible. They can present a real danger if a PCB fails or if they are accidentally used to charge unprotected cells.

I also use Wolf-Eyes 18650s and a Wolf-Eyes charger. If these are not ideal, which chargers come with recommendations? I really must get that multi-meter out!

 

[F_P_R]

Recommended charger is the Pila IBC.
This Charger has no tickle charge. Its more expensive. About 50$.
I recently ordered one but it hasnt arrived yet!

 

[F_P_R]

Here is another thing that i recognized.
The cell comes out of the ch-02 charger @ 3.9v.
I put them in a flashlight and turn it on for 2 seconds.
Then i check the voltage again and its 4.2 now.
Whats the explanation for that?

 

[hazna]

dodgy DMM?

 

[SilverFox]

Hello F P R,

Some chargers utilize the protection circuit in the battery to stop the charge. When the protection circuit kicks in, the voltage can be a little strange until a load is applied and the circuit unlatches. This works both at the over charge end of the spectrum and at the over discharge end. When the over charge protection kicks in, the voltage can read what you are reading. When the over discharge protection circuit kicks in the voltage can read 0 volts.

With a cell that has had the over charge protection circuit latched you need to apply a load to the cell for a second or two before you can get an accurate voltage reading.

With a cell that has had the over discharge protection circuit latched you need to apply a brief charge to the cell that is high enough to unlatch the protection circuit. Then you can get an accurate voltage reading.

The Pila IBC charger avoids the problem with tripping the over charge protection circuit so that should be an improvement.

Tom

 

[mdocod]

Wow, I had forgotten all about that.

I have some older AW cells that do that (they measure 4.0V but then jump to 4.20 after applying a slight load).

Eric

 

[Paul_in_Maryland]

Recommended charger is the Pila IBC.
This Charger has no tickle charge. Its more expensive. About 50$.
I recently ordered one but it hasnt arrived yet!

During my four-odd years using lithium-ions, all my cells were Wolf Eyes. I watched many degrade under the ravages of the CH-02 charger. I finally switched to the Pila IBC.