3.0/3.6/3.7V batteries and how to charge them?

[fvdk]

Hi, I hope some of you can answer some questions I have about the various 17335 size rechargeable batteries. I searched the forums but it is still not clear to me.

I have three types of 17335 size rechargeable batteries (see picture) and they all have different voltages so I wonder what the differences between them is as well as what charger should be used for each of them.



I think the blue 3.7 volt version is a standard non-protected Li-Ion cell that can be charged in an WF-139 or similar type charger as also used for 18650 cells. (with of course the necessary precautions as far as overcharging is concerned).

The blue batteries came with a Cyber CTK12 charger (see picture) that has a rated output of 3.7V and it seems to me that this charger is not suitable for these batteries as it will never fully charge them. Please correct me if I am wrong.



However, I am not sure about the other two types as they are marked 3.0V / 3.6V respectively. I "think" the 3.0V cells are regulated by means of diodes and that they can be charged with the Cyber charger but I am not sure and as I would not like to take any chances, I hope that someone can enlighten me. I have no idea what kind of batteries the 3.6V types are and if they can also be charged in the Cyber charger.

The 3.6V types came with a flashlight that I bought on eBay and for what I paid for it, it is a pretty decent flashlight.



Thanks,
Frans

 

[45/70]

Hi Frans. Generally 3.6 and 3.7 Volts cells can both be charged in the WF-139. The different voltages have to do with how the cells were rated for capacity. They are likely both LiCo (Lithium Cobalt Oxide) cells.

The blue batteries came with a Cyber CTK12 charger (see picture) that has a rated output of 3.7V and it seems to me that this charger is not suitable for these batteries as it will never fully charge them. Please correct me if I am wrong.

I agree. If the charger output is 3.7 Volts, this would be typical of a LiFe charger. These usually output 3.6-3.8 Volts. Not sure what's up with that.


The 17335 cells you have are likely LiFe (Lithium Iron (Fe) Phosphate, or LiFePO4) cells and I would think could be charged with the Cyber charger. There is a chance that these are LiCo cells with diodes to lower the voltage under load, as you mentioned, in which case you would need a third type of charger to charge them which outputs 4.4-4.5 volts. I don't think they are, but while I've seen these cells offered, I've never had any so, I can't be certain. Usually (but not always) LiFe cells have a green wrapper.

If the green 3.0 Volt 17335 cells seem to just barely get a charge in the Cyber, then they may be LiCo cells with diodes. Keep in mind though that these cells are nowhere near 1000mAh regardless of their chemistry, as there are no 17335 Li-Ion cells in existence with that kind of capacity. Another example of optimistic labeling. LiFe cells in this size are typically around 300-400mAh.

Also, the "1800mAh" cells are a joke. Even 16340 primary lithium cells don't have that much capacity, and as far as I know, there are no 17335 primary cells.

And, as tip, don't buy anything flashlight related off of fleabay, unless you know beforehand exactly what you're getting. Fleabay is a known outlet for getting rid of stuff that there's no other practical way to do so.

Hope this helps.

Dave

 

[fvdk]

Hi Dave,

Thanks for taking the time to answer my questions. They very much confirm what I already thought but I was most unsure about the 3.0V cells. I also received an answer from Andrew (AW) which is very similar to your answer.

I agree about your comments regarding fleabay and I will certainly not buy any serious flashlight equipment there but I was looking for a few inexpensive flashlights as giveaways and this one was just a few dollars including shipping so I figured it was worth a try and nothing would be lost if it was crap.

As it turned out, the flashlight is certainly worth what I payed for it and I already ordered some batteries from AW which is something I can recommend to anyone else who has the same questions and concerns I had about these batteries.

I already read about the inflated capacity of these cells and the best I hope for, is that they will have a capacity of around 500 mAh. If not, I will trash them.

So now I only need to find out if the 3.0V batteries are diode regulated or LiFePO4 chemistry. If they are diode regulated than I might as well throw them away as I don't want to buy another charger just for those cells.

Thanks again and I hope others will benefit from my questions as well.

Frans

 

[bshanahan14rulz]

http://www.candlepowerforums.com/vb/showthread.php?t=255943

test on a GTL 18650

 

[DIWdiver]

as I know, there are no 17335 primary cells.

Aren't 2/3A and 123A camera batteries 17335 primaries? Duracell rates them at 1550 mA-H.

D

 

[45/70]

Aren't 2/3A and 123A camera batteries 17335 primaries? Duracell rates them at 1550 mA-H.

Heh, well ya got me there! Generally CR123A's are thought of anymore as 16340 size. It's true that the diameter of an "A" cell is supposed to be 17mm, and "Fat A's" 18mm in diameter.

I very rarely ever use lithium primary 123's, but I just measured three Duracell's and they are 16.3x34mm. While the main descriptor on the label is simply "123", it also says "CR17345" in really small print, so......:shrug:

Anyway, my point was that there are no 17335 Li-Ion cells that come anywhere near 1800, or even 1000mAh in capacity.

EDIT:

So now I only need to find out if the 3.0V batteries are diode regulated or LiFePO4 chemistry. If they are diode regulated than I might as well throw them away as I don't want to buy another charger just for those cells.

I'm fairly certain they are LiFe cells. One way you may be able to tell, is if they charge up to say ~3.70 volts, and then drop down to ~3.3-3.4 Volts after a short time, that would be a pretty sure sign they are LiFe cells. If the voltage were to remain very near 3.70 Volts, or not drop at all, then they may very well be LiCo cells, as LiCo's don't generally loose much voltage after being charged, unless the cells are old.

Dave

 

[fvdk]

Hi Dave,

I'm fairly certain they are LiFe cells. One way you may be able to tell, is if they charge up to say ~3.70 volts, and then drop down to ~3.3-3.4 Volts after a short time, that would be a pretty sure sign they are LiFe cells.

That's exactly what happens
After charging them and putting them in the flashlight, it run for about 40 minutes drawing some 700 mAh before starting to dim so if my calculations are right, that would rate them at around 500 mAh.

As expected, not nearly the advertised rating but at $1.32 including shipping, not too bad and at least usable.

Frans

 

[fvdk]

http://www.candlepowerforums.com/vb/showthread.php?t=255943

test on a GTL 18650

Yes, I had read that review.
All cells I will be buying from now on will be AW cells. Not only great cells but AW's service is perfect as well.

Frans