Li Primary, Li Ion Rechargeable, and Flashlights Oh My

Hi All,

I've recently inherited a batch of batteries both primary, and rechargeable, chargers, and flashlights to boot.

While researching one of the chargers I came across some of the safety guidelines here. I've been reading a lot here, but thought I'd create a post to make sure my combined knowledge that I've read here and elsewhere is true and most importantly safe.

I have 5 flashlights:
- 1 unbranded 3 LED head light that utilizes 3 18650 cells (came with rechargeable in it)
- 1 Amz Vision 1 LED head light that utilizes 2 18650 cells (came with rechargeable in it)
- 1 unbranded 1 LED, 1 laser weapon light that utilizes 2 17345 cells (came with 2 CR17345 primary Duracell brand exp 3/2024)
- 1 unbranded 1 laser weapon light that utilizes 1 16340 cell (came with 1 RCR123A Eastshine 700 mAh brand)
- 1 Streamlight Scorpion incandescent that utilizes 2 17345 cells (came with 2 CR17345 Duracell brand stamped 212205 with no exp date)

I have the following batteries:
- 2 Duracell CR17345 exp of 3/2024 and voltages of 3.109 & 3.110
- 2 Duracell CR17345 stamped 212205 and voltages of 3.150 & 2.938
- 2 Energizer 123 exp of 3/2023 and voltages of 3.084 & 3.085
- 2 Streamlight CR123A stamped 5104 and voltages of 2.790 & 2.755
- 2 Energizer Lithium Photo 123 exp 3/2019 and voltages of 3.116 & 3.116
- 1 Eastshine RCR123A (16340) 700 mAh 3.7V voltage of 3.915
- 2 Fenix 16340 700 mAh 3.7V voltages of 4.000 & 4.003
- 4 Tenergy RCR123A 3.0V voltages of 3.566, 3.597, 0.000, & 0.000 (see summary below about these)
- 2 UltraFire BRC18650 3000 mAh 3.7V with labels stating they have the re/discharge protection circuit. 1 has a damaged label. voltages of 4.107 & 4.108 (see summary below about charging these)
- 6 ATK 18650 3400 mAh 3.7V labeled as having digital protection circuit. Voltages of 3.946, 4.086, 3.951, 4.083, 4.086, & 3.954. One of these had scotch tape over the - terminal.
- 1 Energizer CRV3 3.0V exp of 3/2020 voltage of 3.637 still new in packaging

I have the following chargers:
1 - unbranded, but looks like it comes from several brands 2 cell 18650 charger. (see summary below)
1 - Tenergy brand charger that is new in package with the 4 Tenergy RCR123A 3.0V cells listed above.

This is a summary about the unbranded 18650 charger:

Before I started reading anything here I was using the Amz Vision light that contained the 2 Ultrafire cells. I was used to this with other Li Ion rechargeable tools I have. So I opened it up to see what batteries it has and found these 18650 cells. I went through the rest of the battery and flashlight stuff and found the unbranded 18650 charger. I put the two cells from the flashlight in the charger and the little light at the bottom lit up green. I plugged it in and it began flashing red and green. I went back to doing what I was doing and checked on the cells in the charger a bit later. The light was still flashing red and green and the batteries were cool to the touch. I expected it would eventually turn to a steady color once charged so I left them and forgot about them overnight. The next morning it was still flashing red and green. I figured the were shot, so I unplugged it, took the batteries out and set them aside until I could research it further. Well when I googled the charger trying to find instructions is when I came across some threads here, and my heart sunk when I read about the cautions on charging these, and the Ultrafire specifically.

This is a summary about the Tenergy charger and 4 cells:

The Tenergy charger is still in its package though it is opened. The two cells that show voltage were in plastic still in the clamshell. The two cells that register as 0.000 VDC were installed in the charger, but the charger looks to have never been used. It still has the twist tie on the cord, and prong protector on the plug.

So if you're still with after this long introduction I thank you and will now get to the crux of the post and my questions.

1. Are UltraFire batteries OK to use? I see they are not particularly favored here, but they seem to have charged up all right this time.

2. What about the damaged one? Can I safely repair it? This is a picture of the damage:



3. What about the ATK 18650 batteries? Are these any good?

4. Is the 18650 charger ok, as long as I don't leave them unattended again? Any thoughts on why it never came to a steady green?



5. What about the Tenergy charger. I'm confused by how it is a 3.0 VDC charger and the battteries are too, but the other 3 rechargeable RCR123A are labeled as 3.7 VDC. Can I charge the other 3 in this charger? Are the 3.0 VDC ones designed to be used in devices (like Streamlights) that say do not use rechargeable 123A batteries?

6. The primary batteries. Are these all OK to use? I've tried them in the incandescent Streamlight, and the unbranded weapon light/laser. Some won't power the incandescent, but will power the LED weapon light/laser. I've read mixed opinions on whether this is safe to do or not. Obviously if I do, I'd keep them paired as they are with the voltages the same, and not use the two Duracell with differing charges together.

7. The Amz Vision light that I was using seems to have a smart circuit as it cut out when the cells got low. Anybody know anything about these other two pictured below?







Thats all I can think of for now, but I'm sure I'll have other questions. Thanks in advance to anyone who is willing to help me out with these questions.

Pics edited into original post for clarity.

Thought it would be good to put this all in one, but trying to read through it myself seems like it was a bad idea and confusing.

Sorry about that. Let me try again.

First questions are about the primary cells.

1. Some cannot power the incandescent Streamlight, but can power the LED light/laser. Can I use them in the LED light/laser until they're depleted or is this a bad idea?

2. The pair of 2 Duracell CR17345 stamped 212205 and with voltages of 3.150 & 2.938 VDC. Are these too far apart to safely use together?

Thanks in advance.

ubelongoutside said:

Thought it would be good to put this all in one, but trying to read through it myself seems like it was a bad idea and confusing....

Click to expand...

Yes, your original post above is a bit jumbled, with a lot to unpack.

It did include a number of items of potential concern, which would conflict with "best practices"

Thank you for narrowing the focus, I think you will get more and better advice this way.

ubelongoutside said:

....
1. Some cannot power the incandescent Streamlight, but can power the LED light/laser. Can I use them in the LED light/laser until they're depleted or is this a bad idea?
....

Click to expand...

Is the item you are planning to use to drain these completely, powered by single cell ? and is this a "primary" (non-rechargeable) cell ?

ubelongoutside said:

....
2. The pair of 2 Duracell CR17345 stamped 212205 and with voltages of 3.150 & 2.938 VDC. Are these too far apart to safely use together?
....

Click to expand...

Correct, it would be potentially risky to run these in series.

archimedes said:

Is the item you are planning to use to drain these completely, powered by single cell ? and is this a "primary" (non-rechargeable) cell ?

Click to expand...

The LED light/laser is what I'd like to use to completely drain them, and it is a 2 cell device.

The cells I'd be depleting in this would be the primary (non-rechargeable cells) that have the same or very close voltage readings. I suspect they were being run as pairs given the close readings on the cells that are the same make with the exception of two.

archimedes said:

Correct, it would be potentially risky to run these in series.

Click to expand...

OK, I do have a single cell weaponlight I can use these in then, and maybe the others if it is risky to use them in a double cell light.

ubelongoutside said:

.... Can I use them in the LED light/laser until they're depleted or is this a bad idea? ....

Click to expand...

There is a spectrum of risk and so, to paraphrase Ghostbusters (on crossing the streams) , what do you mean by "bad" ?

ubelongoutside said:

The LED light/laser is what I'd like to use to completely drain them, and it is a 2 cell device.

The cells I'd be depleting in this would be the primary (non-rechargeable cells) that have the same or very close voltage readings. I suspect they were being run as pairs given the close readings on the cells that are the same make with the exception of two....

Click to expand...

On a more serious note, there are more potential factors in matching cells than simply their open-circuit voltage (such as age, internal resistance, passivation, etc)

If you are uncertain as to the "history" of these particular cells, and especially if you are unfamiliar or uncomfortable with the safety issues, it may be prudent to stick with single cell devices for these.

Thanks for all of the info archimedes. I'll stick with them in a single cell light.

I guess my next big question is the ultrafire batteries. From reading here it sounds like they're not highly recommended. Also there is the damage to the one. Should I try to use these things? What about the damage to the one, is it repairable? I have no lights that use these, just the 2 I inherited, and they are 2 and 3 cell models.

Just to chime in really quick, whenever I'm using a multi cell light with multiple cells, which isn't often, because I always try to use a 16650 instead of two 16340 cells, I always buy those cells as a pair and run them exclusively together in the same light at the same time for the lifetime of the batteries.
So for example, my Spy flashlight has 2 sets of cells dedicated to only that one light. They never get used individually and I always pay attention to voltage before charging and then how many mah they take in to be certain they are charging and discharging similarly.

ubelongoutside said:

Thanks for all of the info archimedes. I'll stick with them in a single cell light.

I guess my next big question is the ultrafire batteries. From reading here it sounds like they're not highly recommended. Also there is the damage to the one. Should I try to use these things? What about the damage to the one, is it repairable? I have no lights that use these, just the 2 I inherited, and they are 2 and 3 cell models.

Click to expand...

For batteries, I typically first check the @HKJ reviews.

I think that UltraFire are generally "rewraps" so it is hard to compare them, even to themselves.

These were a couple of reviews I found with a brief search of the battery review database, but not sure if these are the same "exact" version as what you might have ...

https://lygte-info.dk/review/batteries2012/UltraFire BRC18650 3000mAh (Red-silver) 2015 UK.html

https://lygte-info.dk/review/batteries2012/UltraFire BRC18650 3000mAh (Red-silver) UK.html

https://lygte-info.dk/info/batteryDisassemblyUltraFire UK.html

Just saw the photo of the damaged cell above .... Attention that has a significant risk of short circuit, as pictured, with potentially catastrophic outcome

archimedes said:

These were a couple of reviews I found with a brief search of the battery review database, but not sure if these are the same "exact" version as what you might have ...

Click to expand...

When searching, try my new table: https://lygte-info.dk/info/batteryIndex.html
You can type in "Ultrafire" and it will list all Ultrafire batteries.

There are a few good Ultrafire, but not in 18650 size.

HKJ said:

When searching, try my new table: https://lygte-info.dk/info/batteryIndex.html
You can type in "Ultrafire" and it will list all Ultrafire batteries.

There are a few good Ultrafire, but not in 18650 size.

Click to expand...

I think my point was more that with UltraFire ... it is sorta difficult to know what one might be getting, wrapper aside

archimedes said:

I think my point was more that with UltraFire ... it is sorta difficult to know what one might be getting, wrapper aside

Click to expand...

Not that difficult, try comparing rated and actual capacity in this list:

archimedes said:

Just saw the photo of the damaged cell above .... Attention that has a significant risk of short circuit, as pictured, with potentially catastrophic outcome

Click to expand...

I was afraid of that. I read elsewhere here about when damage to the wrap is bad, and the example image of what you don't want exposed looked almost exactly like the one I have.

I'll have to search the list referenced above and see if these are worth saving or not.

Thanks again to all who have responded to help me get this "mess" figured out. I have a lot of rechargeable NiMH rechargeable and so when I was offered more I gladly accepted. When I found the Li Ion ones in there I thought to myself "cool", but when I started searching about the charger is when I ended up here and became concerned. Lets just say I did exactly what it says not to do in one of the newbie threads here. On the plus side it didn't burn the house down, but I'd rather not gamble, given the luck I've had of late.

My next question then would be the other 18650 batteries. Does anyone have experience with these? I couldn't find them in the table you've put together HKJ. I believe they were bought from Amazon along with the all of the other rechargeable lithium batteries I inherited based off receipts we have found.

ubelongoutside said:

I couldn't find them in the table you've put together HKJ. I believe they were bought from Amazon ...

Click to expand...

Amazon US is not a place where I buy batteries for test, the problem is shipping.