Recharging for dummies-part deux!

olddogrib

Newly Enlightened
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Since the answer to my other post appears to be "yes" (XTAR MC1 Plus compatible) based on RCR123a being 3.7 volts, I'm browsing for a couple of batteries only if my charger will work. It seems that most RCR123a's are between 700-800 mAh until I came across some at WallyWorld (EBL's) listed at 2800 mAh. Is this a misprint? The price is attractive if not. These are going to be used in a predator hunting laser light, which I'm guessing is a "high drain device"? I've seen enough posts of folks experiencing incompatibilty of their 16340/RCR123 cells with their lights that I want to err on the side of caution. Also, I've noticed an inordinate number of these battery manufacturers specify they are for use with "Arlo Security Cameras". What difference does it make? Is their something special about those that make them unusuable for other applications? Thanks
 
"RCR123A" is entirely ambiguous. There is no way to know what the voltage is just by that descriptor.

CR123A primary cells are nominally 3V cells, but new they're about 3.2V. This is why any number of label of RCR123A secondary rechargeable cells may be 3.2V LiFePO4 cells. But RCR123A may just as often be 3.6V/3.7V Li-ion 16340 cells.

The only way to know is to look at the cell and read the voltage off the cell. If it says 3.2V, it's LiFePO4 chemistry, aka IFR and LFP, which terminates charge at 3.7V. But if the cell has "3.6V" or "3.7V" printed on it, then it is more commonly known as a 16340 Li-ion cell (even though LiFePO4 is also a Li-ion cell, conventionally Li-ion refers to the higher voltage cells). A lot of manufactures are selling Li-ion cells as "RCR123A" even though they will destroy some devices that are expecting 3V from CR123A primary cells.
These will charge in your Xtar charger, have tested well as high capacity, so the mAh rating is accurate:
Vapcell T8 INR16340 3.6V 850mAh 3A Button Top

HKJ test/review of Vapcell T8 INR16340 850mAh

Probably best to abandon "RCR123A" nomenclature and just refer to the cells you need as "16340" cells to avoid confusion and ambiguity.

until I came across some at WallyWorld (EBL's) listed at 2800 mAh. Is this a misprint?
EBL 2800 are AA-sized NiMH 1.2V rechargeable batteries, not 16340 Li-ion cells, and your Xtar charger will massively overcharge them.

Also, I'm not in charge here, and you can do as you please, but there was really no reason to start a new thread, could have posted this in the first Xtar thread.
 
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Hmmm...

Ctrl-f on that site is your friend. Lots of lying going on. At low discharge rates, some cells can make it to a real 900mAh. High discharge ones (usually INR) tend to have lower capacities, but the difference isn't too big, today (since mAh is going to vary by discharge rate anyway, they get away with a bit of fudging the numbers). Keeppower and Vapecell tend to be pretty honest about their performance, are usually easy to find, and not expensive.

High discharge is kind of ambiguous, as far as threshold. But, 1-2A is generally OK with any 16340 in a typical chemistry. The IMR, INR, NCR (totally not at all like INR), etc. chemistries are safe for 5-10A in a 16340 size, sometimes more, and are safe to discharge to a bit lower voltages than LiCo/ICR.

Those security cameras probably use rechargeable 16340 cells, internally. Common Lithium Ion chemistries are full around 4.2V, and nearly depleted by 3.6V. Lithium Iron Phosphate vary by maker, but tend to be full by 3.6V or lower, and almost dead by 3.2V or so. Primary CR123As are full at about 3.2V (I just got some new Panasonic ones, and they read 3.25V), and are nearly dead by about 1.5V.
 
LFPs don't measure well by voltage, for what it's worth. Voltage drops off a cliff suddenly at the end of discharge. You really need a coulomb counter to be accurate.
 
I just rechecked Walmart website. The EBL cells I'm referring to are listed as such:

EBL 16340 RCR123A Batteries 4-Pack 2800mAh Rechargeable CR123A Lithium-Ion Batteries Arlo Batteries for Arlo Cameras, Reolink Camera, Flashlight
[/H1]

$8.59
 
FYI
you can paste links here and they will automatically become hot, like this


My expectation is EBL did some in house testing at something like 0.002mA current draw and found that at a teeny tiny current draw, their cells show a lot of capacity. I can't find even one review or test of these cells. As always, with anything, if it sounds too good to be true, it's probably absolutely true! Isn't it always? Something like that, but probably not. But the price is low enough, the possible damage is limited. Do you gamble? Because that's what those cells are, a gamble, and I think a very poor bet at that. Just MHO, because I don't know them. FWIW, the capacity ratings are inflated for all of EBL cells of any chemistry, but sometimes possible at some negligible current. I've seen EBL exaggerate before, but probably never as much as on these 16340.

If not a gambler, I am going to again recommend
Vapcell T8 INR16340 3.6V 3A 850mAh
which are fantastic, high capacity high current cells, and known to be so by all that use them, including me. And I am personally unaware of any higher capacity 16340 cells.

Or if you want cells protected against overdischarge, overcharge, overcurrent and short circuit, of which the Vapcell can tolerate overdischarge and overcharge (but only to a point), then get
Keeppower ICR16340 3.7V 1.6A 800mAh
and though I don't personally use these cells, Keeppower consistently releases only high quality cells, and I love and use all I can get my hands on.
 
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My plot sickens. I appreciate the CPF patience with admitted "dummies"...I nearly went down a rabbit-hole! I asked the guy who recommended my laser light what he uses...ULCR123 Ultralast, which I recognized immediately as the LiFePO4 chemistry you warned about putting in my XTAR ANT. I don't know if he knew or was just trying to reproduce the 3V of the primary it came with. There was nothing in the specs. that came with it. I even called Cyclops tech support and they said stick with 3.2v or less. You'd think that China might mention such a requirment in the instructions. Now that I think y'all have me on the right page, any reccomendations for 3.2v? I'm just going to have a designated charger also and keep it separate. I'm getting too old for this chit, but thanks again!
 
I don't use them because of the low capacity of LiFePO4 in such a small cell. But if I did need them, because the gold standard AW brand blue cells are no longer available (factory flooded and AW never came back), I would get the SureFire SFLFP123 Charger Kit with LiFePO4 charger from Battery Junction, along with a set of extra cells.

Nearly every battery manufacturer lies about capacity. Surefire's capacity rating is probably dead accurate, and they are intended for high current lights, so that supports that these are good cells with an accurate capacity rating. You may see other cells, such as from Soshine and Tenergy, claiming to have more capacity. Don't believe it, they're basing their rating on low current applications, and they likely top out at 400mAh. I haven't seen any verified capacities for these sized cells in LiFePO4 over 450mAh.

Generally, when it comes to Li-ion cells, only buy cells labeled by known good manufacturers from known good sellers, because there are a lot of counterfeits and crappy labels.

That means, in no particular order, Li-on cells made labeled by Surefire, Samsung, Sanyo/Panasonic, Keeppower, Vapcell, Sony, Molicel, Imren, Efest, or LG.

Avoid Ultrafire and especially Trustfire, and pretty much any name with fire in it other than Surefire, and apparently Fandyfire iirc, CPF members have said was decent.

And only sold by Surefire, Battery Junction, illumn, Liion Wholesale, 18650 Battery Store, and IMR Batteries. There may be other quality sellers, but I am pretty sure about these sellers and know for certain that Surefire, Battery Junction, illumn and Liion Wholesale are definitely good.

I have had good luck with getting only those name-brand cells (specifically Keeppower) off AliExpress, and with Alibaba you can order direct from the manufacturer (such as Keeppower or Vapcell), with caveats like large minimum orders, so presumably the actual manufacturer isn't going to sell you counterfeits.

You can get a charger that will charge both 3.6V/3.7 and 3.2V cells, as well as polymer 4.35V cells and NiMH 1.2V cells, and they aren't too expensive, such as a NiteCore D4 (this is the previous gen, which is less expensive while supplies last), which will automatically detect NiMH 1.2V and Li-ion 3.6V/3.7V, but it requires manually changing the charge program for LiFePO4 3.2V and polymer 4.35V. Since you already have a Li-ion charger, and your need for these cells seems to be specific, you may as well get a dedicated LiFePO4 only charger, and though I don't know that Surefire charger, I can only assume it's fine for their own cells.
 
It appears that the XTAR MC2 will also do 3V RCR123? I understand why the designation is meaningless when they can refer to cells from 3-3.7 volt, but at least now I know I can't use 16340.
 
It appears that the XTAR MC2 will also do 3V RCR123? I understand why the designation is meaningless when they can refer to cells from 3-3.7 volt, but at least now I know I can't use 16340.

No.

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Like I said, best to stop using "RCR123A" and instead use chemistry/cell size/nominal voltage, where

nominal voltage --------------------------------------> charger termination voltage
  • 3.6V - ICR = LiCo / LiCoO2 ------------------------- end charge 4.2V
  • 3.7V - IMR = LiMn ----------------------------------- end charge 4.2V
  • 3.6V / 3.7V - INR & NMC & NCR = LiNiMnCoO2 - end charge 4.2V
  • 3.2V - IFR & LFP = LiFePO4 ------------------------ end charge 3.7V

respectively, that is ICR Lithium Cobolt; IMR Lithium Manganese; INR Lithium Nickle Manganese Cobolt; IFR Lithium Iron Phosphate.

Place abbreviation next to cell size, where the first two numbers are the cell diameter in mm, and the second two numbers are the cell length in mm, ignore the last trailing zero (and the measurements are never exact, often 0.5mm larger in both dimensions):
  • 10440 / AAA-sized[/SIZE]
  • 14500 / AA-sized[/SIZE]
  • 16340 (CR123A-sized)[/SIZE]
  • 16650 (2x CR123A-sized)[/SIZE]
  • 18500 (like a fat AA-sized, common in solar lighting)
  • 18650 / 4/3A-sized (more or less)
  • 21700 (like a super capacity 18650)
  • 26500 / should be C-sized, but often fatter than C
  • 26650 (often as not 70mm long)
  • 32650 / roughly D-sized
  • (D cell would actually be 34615, 34.2mm x 61.5mm, but no one uses that)

Such that if you wanted a certain chem and voltage of AA-sized cell you might look for,
IMR14500 3.7V

and in your case, you want a CR123A-sized cell in a near compatible voltage to 3V CR123A, so then
IFR16340 3.2V
(At least that is what I gathered; I have no idea. You have an idea. Look at the spec of the device you're using and what voltage cells it takes.)

Because "RCR123A" is ambiguous it will get you into trouble. Best to ignore it and get into the habit of looking specifically at what the nominal voltage is, which generally you can often then match to chemistry, not always, but sometimes always. Any 3.2V cell is going to be LiFePO4, which terminates charge at 3.7V, so if a charger terminates charge at 4.2V, you know it will overcharge that cell, and the charger is inappropriate for the chemistry.
 
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  • 18500 (like a fat AA-sized, common in solar lighting)
  • 18650 / 4/3A-sized (more or less)
  • 26650 (often as not 70mm long)
  • 32650 / roughly D-sized
  • (D cell would actually be 34615, 34.2mm x 61.5mm, but no one uses that)
17500 is A size cell. (17mmx50mm)
18500 is AF size cell. (18mmx50mm)
17650 is 4/3A size cell (17mmx65mm)
18650 is 4/3AF size cell (18mmx65mm)

32650 is longer D size cell (32mmx 65mm)
-------
4/3A sometimes called 7/5A
21700 is longer version of B cell.
 
This is apparently wrong then, go to the link and look under specs.
If you mean where it lists "3V RCR123A," it gets a bit instructive, and underscores how sellers are confusing the snot out of everyone.

There are sellers that claim LiFePO4 3.2V 16340 cells are RCR123A. There are sellers that claim Li-ion 3.6V/3.7V 16340 cells are RCR123A. But technically, the only cells that could accurately be called RCR123A are special Li-ion 3.6V cells that have a special protection circuit that limit the forward voltage to 3V, and they are intended as a direct voltage-matched secondary rechargeable replacement for actual 3V CR123A primary cells. They're still Li-ion 3.6V cells, and they terminate charging at 4.2V when at full capacity, they just only provide 3V, thanks to the voltage limiting circuit.

So technically, that spec is correct, but it is easy to see how it is confusing and could be misinterpreted to mean LiFePO4 3.2V cells are compatable. but they're not. That charger doesn't detect anything. No matter what chemistry cell you place in it, even if you put a 1.2V NiMH cell in it, it will charge (or try to indefinitely) to 4.2V. That is why that charger and any Li-ion only charger like it is technically compatible with those special 3V cells, because though they only provide 3V, they terminate charge and are at full capacity at 4.2V.

Think about it this way. There are chargers that can automatically detect the difference between 1.2V NiMH cells and 3.6V/3.7V cells. It seems pretty obvious how they must do that, if the voltage is below 2V, it assumes it's NiMH, and if the voltage is above 2V, it assumes it's Li-ion.

But a LiFePO4 cell will still test above 2V, so how could it know the difference between LiFePO4 and Li-ion? When capacity is depleted, these cells test roughly the same amount of voltage. Afaik, a charger can not automatically detect the difference between these chemistries.

There are chargers that will charge all three chemistries, but they solve this by only automatically detecting between 1.2V NiMH and 3.6V/3.7V Li-ion and requiring the user to manually set the charger for 3.2V LiFePO4 cells.
 
The bar hasn't announced "last call" yet have they, lol? I went with the Surefire 3V cells & charger combo, that should end it...now I need a "waterhole"! I'd "bet the farm" Cyclops has a battery division, so I still have no idea why China would make a product with obvious liability concerns that could largely be avoided by simply stating "Do Not Substitute Rechargeable Cells" or at least clearly stating which ones won't fry the device. Maybe all their R&D budget is currently going to balloons!
 
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