Bad charger or bad cell??

[Robocop]

I have a Wolf-Eyes CH-02 charger as well as several Wolf-Eyes 18500 cells that I have used regularly on duty for several years. I recently noticed that the light will shut off after maybe 5 minutes of use and this is fresh off the charger.

After charging the cells show 4.15 volts and when the light shuts down one of the cells shows 2.07 volts. I put it on the charger and in a few minutes it shows green as if fully charged. I check the voltage and it is 4.15 however after maybe 5 minutes of use it again drops to around 2 volts.

Is this a symptom of a bad charger or a bad cell? I am curious as I tried a search for information and did not find my answer however did find that many did not like the standard CH-02 charger and opted to use the Pila.

I have several spare cells coming my way and if this is a charger problem I do not wish to damage my new cells. I will say that these cells and charger have done me well for several cycles. I have used WE cells as well as alternating AW brand cells and they all have many cycles of use.

The weird part I just discovered is that when the cells in question are charging the charge light will quickly turn green as if complete. When I move the charger or pick it up it seems as if the movement triggers something and the light turns red again as if charging. It only stays red for a few seconds and quickly goes back to green as if again complete. It only seems to do this with certain cells however it seems weird to me that a bad cell would make the charger appear to have a short or something.

I have just bought about 100 dollars worth of batteries for duty both 150 and 168 size and also spent close to 200 dollars on a new duty light WE light kit with identical charger included. I am not sure if I can get an expensive charger any time soon however I am not even sure if the charger is the problem or simply worn out batteries. When batteries do go bad after usage what are the most common symptoms? I always have had my past batteries simply show much less runtime however never had any show the sudden drop from full charge to almost nothing.

Thanks for the help on this as I know almost nothing about chargers nor battery chemistry.

 

[peteybaby]

I don't have any 18650s, but I have li-ion camera batteries. I've seen the same thing happen with those. After about 4 years of use (and I've read that li-ion batteries start dying at around the 4-5 year mark regardless of how often you use them), my batteries started charging faster than before, and draining much faster than before. Eventually, the charge only lasted a few pictures (as opposed to hundreds of pictures when the batteries were new), and I had to buy a new battery. The new battery charges fine and holds its charge fine, using the same charger as I used on the dead batteries.

I read that the problem is that the batteries develop higher internal resistance. So while the energy is still stored in the battery, trying to draw it out causes the battery voltage to drop a lot.

So I would think that in your case, especially since you said they are several years old, you also have bad batteries.

 

[Robocop]

I believe you may be correct about the age factor. I was a little suprised as my problem seemed to develope very suddenly without any noticed warning of decreased performance.

I had an old Commander that I went through several B90 Cells with and I always had several months notice with the cells just slowly losing their output. I was just now trying to inspect my current charger and noticed a weird buzzing sound while charging certain batteries. It seemed to increase and decrease as I moved the battery around in the charging bay and I have never noticed this sound before.

The good news is that I have a brand new charger coming and I may just be safe and use the new one only. I plan to use a 3 cell 18500 set up and was hoping to be able to use my current charger as well as the new one to charge 3 cells at at the same time.

 

[Monocrom]

Best thing to do is try out the old cells on the new charger, once it arrives. If they start performing well again, you know it's the charger. If they don't, you know it's the cells. Possibility of new charger being defective is eliminated by charging up the new cells on it. If they fail to perform well, then you have two bum chargers.

When it comes to charging more than two Li-Ion cells, I use the Soshine charger I got at Lighthound.com. There's two variations. One has 4 charging bays. (Two for shorter cells, two for longer ones). I have the other one. All 4 charging bays designed for longer cells. Toss in three 18500 cells and power them up all at once! Very useful for the M90 w/ extender and 13volt lamp.

My Soshine works well. But it has a bit of a low-rent feel to it. Mainly due to the thin, black plastic, cover that is spray painted silver. Other than that, no issues.

 

[Robocop]

You know now that I think back I remember a few months past I was not paying attention and placed one of my WE cells into the charger backwards. I quickly realized my mistake and removed the cell however maybe it messed up my cell or my charger.

I have also dropped my light several times as well as the cells and possibly messed up the protection circuit inside. Honestly for the many years of usage I have received from both cells and charger I can not comlain at all. I am mainly concerned about knowing if the charger is not working correctly as I do not want to use it on my fresh supply of cells.

I only have one other charger capable of charging the 150s and 168 size cells and it is a cheap DSD model bought long ago. I did not think to try the cells on that charger however I will do so tomorrow. I am searching the forum now trying to find a place to buy the Pila charger. The JS Burly link I found is not working anymore and for the life of me I can not remember any others who had the Pila brand.

The old threads I found listed the Pila at 49 dollars.....if it is still available can anyone say what is the average price of the charger today?

 

[Monocrom]

I am searching the forum now trying to find a place to buy the Pila charger. The JS Burly link I found is not working anymore and for the life of me I can not remember any others who had the Pila brand.

The old threads I found listed the Pila at 49 dollars.....if it is still available can anyone say what is the average price of the charger today?

Best bet for Pila products is BOG.

Ironically, the price has stayed the same....

LINK ~ http://www.bugoutgearusa.com/bach.html

 

[Tekno_Cowboy]

Best bet for Pila products is BOG.

Ironically, the price has stayed the same....

LINK ~ http://www.bugoutgearusa.com/bach.html

Thanks for the link!

 

[Monocrom]

Thanks for the link!

Happy to help.

 

[Robocop]

I received most of my orders today however have not had time to charge anything on the new charger. If it does turn out to be a damaged cell would it somehow damage my new charger if I tried to charge the cell on it?

 

[SilverFox]

Hello Robocop,

I am leaning toward you having cell issues...

When cells develop higher internal resistance they usually come off the charger at below 4.0 volts. Since yours are above that, the scrutinity changes to the protection circuit.

If you are feeling adventuresome, you can cut the protection circuit off and see how the cell functions as a bare cell...

There should be no problems charging the cells on your new charger.

Tom

 

[Robocop]

Hello Tom and as always it is nice of you to come to my rescue with the tech stuff that I know almost nothing about. The good news is I did receive a large supply of new cells today however the new lights and the new charger did not arrive today. Both packages shipped out the same day however I think Lighthound is a little closer than Pacific Tactical.....hopefully tomorrow the other package will arrive.

I may try removing the protection circuit however with brand new cells so affordable I will probably just go ahead and dispose of it and use the new ones. Honestly even if it did work fine without the circuit I would always be very nervous running it with other 2 cell set ups.

I sure do hope my package arrives from PTS tomorrow and with the next two days off I will have plenty of time to charge and try out my new toys.

Thanks again for the help to all

 

[Robocop]

Tom you may have been correct as I got much better results from removing the protection circuit. before removal the cell showed fully charged just off the charger and quickly fell to 2.0 volts after being under load for a few minutes.


After removal of the circuit the cell showed back up to 4.17 volts and seemed to hold ok. I never imagined the protection circuit could cause problems of holding power and assumed it would simply lose protection and allow a cell to operate normally.

Well it was fun to experiment however I now have a cell with no outside wrapper and its past behavior would make me worry to even use it anyway. The good part is that I now see how neatly the protection circuit is tucked away under the battery wrapper and better understand how they make a protected cell......interesting however dangerous to play with misbehaving cells for an amateur like myself....

 

[SilverFox]

Hello Robocop,

Now that you have seen how the protection circuit fits on the cell, and how it is made, you may want to consider what could happen if you happen to drop your light, just right.

I assume that you use your lights during work and expect them to light up when needed. Dropping a light can damage the protection circuit. It doesn't happen every time, but it is something to be aware of.

A good back up is to have an extra cell(s) should damage occur mid shift. You can find a tube to carry extra cell(s) and pad the ends with a piece of foam to cushion against impact.

Tom

 

[mdocod]

Just a reminder, don't charge your now unprotected cell in the wolf-eyes charger.

 

[Robocop]

I did not try to charge or even use the cell at all as it made me nervous to even mess around with it anyway. I am using some of the AW 18500 replacements in my Raider while waiting for my M90 to arrive from PTS.

I did notice when I removed the circuit the old WE cell was labeled as a Copia brand and from what I remember about the older Pilas this was a decent battery. I really have no complaints at all as this cell has lasted many shifts and several hundred charges....money well spent.

I do carry spare cells on duty however never thought to worry about impacts or damage. I honestly had no idea these protection circuits could be so fragile or could impact the performance if dropped.

 

[etc]

I think I have something similar going on with a AW cell, 18500.

It never charges above 4.1V. The other cells charge to 4.2V with Pila.

Put them in Surefire with M60 (Leef body), they work for 5 mins, then cut out. Other cells work fine.

 

[Robocop]

I just went through my first cycle on my new 18500 cells and was very suprised to see the runtime not very good. I know the HO-9L is pulling some higher power however I was still suprised to see the protection circuit trip with a single night of use.

I had been testing the cells with several other lamps and it had maybe 10 minutes of total use before I began patrol. I am hoping that a few charge-discharge cycles may help a little to improve the runtime. I am very happy with my new set up and again my old cells and factory WE charger did me very well for several years. I may have a chance to get a Pila charger and am seriously thinking of doing so.

I disposed of the older cells that were acting poorly and with luck these new ones will give me the same good results of the replaced ones. I did notice that my older WE charger would show the cells coming off the charger at about 4.2 volts while thus far all of the ones charged on the new one show all to be at 4.14 off the charger.

I have not yet left a pair on the charger for over 2 or 3 minutes after the green light comes on so I am not sure if the voltage would be higher if left on the charger longer after the green light came on.

 

[Robocop]

Ok this is weird.....

As I said earlier my new cells just tripped the protection circuit tonight and I quickly swapped over to my spare set and finished my shift. I figured all the testing and playing around depleted the cells so when I got home I placed them on the charger. After about 30 minutes the light went green and I removed them to show both at 4.15 volts.

I thought that because the cells had drained low enough to shut off they would surely take at least 2 hours or more to charge. I am going to try and cycle them again starting from a fresh charge and see how long before they shut off. It may be my imagination however I really did not feel like they had that much usage on them to shut down but again I know the draw is much more than what I was using.

Just can not figure out why they showed fully charged after only 30 minutes on the charger. I tried searching and can not find out what voltage these cells trip the circuit at (these are the new AW 18650 versions) Does anyone know the specs on the protection circuit both for discharge as well as over charge protection?

 

[Monocrom]

All I know is, 30 minutes is way too short. A couple of times, while using 2x18650 AW cells in my high-output Solarforce L600, the protection would kick in after 33 minutes of use. And would require 5.5 hours of charging on my Ultrafire WF-139 charger.

Something's not right here. 30 minutes isn't even close to how long it should take your AW cells to charge up, after the protection kicks in.

 

[B'hamFAL]

Most 18500's are 1400mah and the HO-9 is pulling 2.3 amps (AKA 2300ma or milliamps).
Bestcase runtime then is (1400/2300) * 60 = 36 minutes. Such is the penalty of a small bright hotwire.

The WE 13v bulb on 3x18650's should give (2200/1550) * 60 = 85 minutes.
The EO-13 bulb on 18650's chould give (2200/2200) * 60 = 60 minutes.
The WE p7 head pulls 1.33 amps off 2 18650's giving a runtime of (2200/1330)*60 = 90 minutes.

Note these runtimes are without derating the battery's claimed capacity at all. Typically 80% or so is all you'll get out before the protection kicks in.

You're on your own for the charging time problem/issue but I'll add that cells used in the same light often have 10-20 minute different charging times in my two bay chinese charger, so there's obviously some manufacturing variance going on with batteries and charging bays. I also have two older AW18650's that 'll go green on the charger but if you take them off and drop them right back in they'll start charging again for another 10-30 minutes. A third cell purchased at the same time stopped charging. All three cells while over a couple years old have only had 30-40 charge cycles. They have however spent two summers in the trunk of the cruiser in 100+ deg heat.