Why does my Ultrafire charger have a switch that says 3.6v or 3.0v ???

[busseguy]

I have an ultrafire battery charger that I bought with my protected AW RCR123 batteries which say on them 3.7v.

It has always been switched to the 3.6v side when I charge, but I have no idea if it would be better switched to the 3.0v side.


Please help I'm very confused.

Thanks in advance

 

[chrisWELD]

3V is for charging LiPO4s - at least that's what I bought this charger for from AW. I use Lithium phosphate 3V RCR123's in my wife's E1E and E1L

 

[Beacon of Light]

I hope you didn't irreverseably damage those 3.7 v cells

 

[old4570]

Link to 3v li-ion batts

3v Li-ion top out at 3.6v / sometimes there also called 17335
3.7v Li-ion top out at 4.2v / also called 16340

Your charger can charge both ...

You need to be a little careful with the CR123A class of batteries due to the variations .

 

[mdocod]

There are other chargers out there labeled for use with a different kind of 3.0V cell that actually charge to ~4.5V and can do serious harm to a normal 3.2V LiFePO4 or 3.7V LiCo.

The UF that you have is the "other" type, that charges to around 3.6V on the 3V setting and wouldn't introduce any significant safety risks.

Ask before exploding is a good rule of thumb.

 

[45/70]

Hi busseguy.

Your charger should be set to "3.6" Volts to charge the "3.7 Volt" LiCo (Lithium Cobalt oxide) AW cells you have. It probably won't damage them to charge them with the "3.0" Volt setting, but they will end up being only partially charged, eg. <40%. As has been pointed out, the "3.0" volt setting is for LiFePO4 (lithium iron phosphate, or "LiFe") cells.

Not to make things more complicated, but I'm sure it will, there are also LiCo cells that have diodes installed within the cell to reduce the output voltage. These cells are usually labeled "3 Volts", but are actually a bit higher than that, similar to LiFe cells when under load. This type of cell requires a higher voltage charger than a LiFe cell, and also higher voltage than a regular LiCo cell, to overcome the diodes, usually 4.4-4.5 Volts.

As old4570 said, you have to be careful matching cells to chargers with all these different chemistry cells. The effect of using the wrong charger with the wrong chemistry, can range from simply not fully charging the cell, to considerably overcharging the cell, the later which may just shorten the cycle life of the cell, or in the case of charging a regular 3.6-3.7 Volt LiCo cell with a "3 Volt" LiCo charger, could be potentially dangerous, as the end voltage will be considerably higher than is recommended.

EDIT: mdocod, you beat me to it!

Dave

 

[Beacon of Light]

I am thinking of buying these for my laser that needs 2 CR123a batteries. These should work as they are unprotected cells so they SHOULD fit and be the 3.0 volts it needs and the 650mAh while probably overstated, should be ok for my uses. Wouldn't these also need the WF-138 to be set to 3.0 Volts on the charger?

 

[busseguy]

Thanks guys for all your help.
Yes I have always charged those 3.7 volt AW cells on the 3.6 setting, so it looks like I'm good.
Thanks again

 

[HKJ]

I am thinking of buying these for my laser that needs 2 CR123a batteries. These should work as they are unprotected cells so they SHOULD fit and be the 3.0 volts it needs and the 650mAh while probably overstated, should be ok for my uses. Wouldn't these also need the WF-138 to be set to 3.0 Volts on the charger?

According to Soshine they are 3.7 volt LiIon with a diode.
I do not known if they can be charged on a regular 3.6/3.7 volt charger or they need a higher voltage. Looking at Soshines website it looks like they only need 3.6/3.7 volt charger.

 

[Beacon of Light]

So if these are 3.7 volts, then doubling that, once the laser is turned on the initial blast would fry it if it was expecting only 6 volts, correct? Damn, I I totally regretting ever getting involved with CR123 batteries. Total frustration.

 

[HKJ]

So if these are 3.7 volts, then doubling that, once the laser is turned on the initial blast would fry it if it was expecting only 6 volts, correct? Damn, I I totally regretting ever getting involved with CR123 batteries. Total frustration.

3.7 volt with a diode, this reduces the voltage to around 3 volt. It is not exactly the same as a CR123, but it probably the closest you can get in rechargeables.

 

[Beacon of Light]

Since there is a diode in there wouldn't that make the diameter wider than a typical CR123a? This was the problem with the Ultrafire 880mAh RCRs I already have that are useless since they do not fit.

 

[HKJ]

Since there is a diode in there wouldn't that make the diameter wider than a typical CR123a? This was the problem with the Ultrafire 880mAh RCRs I already have that are useless since they do not fit.

It might, Soshine specify 17x35.5 mm on the webpage (See my post above for link), but this might not be the actual size.

 

[45/70]

Wouldn't these also need the WF-138 to be set to 3.0 Volts on the charger?

Beacon, those are diode voltage reduced LiCo cells. As HKJ said, they will not charge properly with a WF-138. You could charge them with the 3.6 Volt setting, but they will not achieve full capacity. They would charge very little, if at all, using the 3 Volt setting.

There have been several threads started asking why the poster's 3 volt Soshine cells don't have much capacity. The reason is because the cells do not get a full charge with a normal LiCo charger. They require a charger that charges to 4.4-4.5 Volts, to receive a full charge. Why Soshine says that on their website, is beyond me, but then again, so is Soshine.

As to whether they would be OK in your laser, I don't know, but these cells do have a slightly higher voltage than a CR123A primary cell, particularly when the device is first turned on. Depending on the load applied, these cells usually run somewhere between 3.2 and 3.4 Volts. LiFe cells are nearly always 3.2 Volts under a "normal" load, as they suffer less voltage drop under load than LiCo cells.

I'll add that I have a 2xCR2 laser that I use two RCR2 LiFe cells in, without problems. LiFe cells have a similar voltage to 3 Volt LiCio cells, but lack the "spike" in voltage when the device is first turned on.

Since there is a diode in there wouldn't that make the diameter wider than a typical CR123a? This was the problem with the Ultrafire 880mAh RCRs I already have that are useless since they do not fit.

The diodes in these cells are mounted under the positive nipple, and there is no strip running up the side of the cell, as with "protected" cells. The size is the same as an unprotected cell.

Dave

 

[VidPro]

i have tested the doubble diode "3V" regulated down 3.7v li-ion on the cheap 4.2v chargers, and it wont blow anything up or hurt anything.
it will put a light charge on them, and allow them to be used Temporarily, in a pinch.
it charges them to 3.6-7 around there somewhere. (not even 50% charged)

I have one that also seems to utalise protection curcuit, it is an Orange Powerizer , i was surprised to realise that it wouldnt go over about 4.7-8v, and sure enough there is a very thin strip down the side of it, barely visable for connecting the curcuit.

its like the little battery that could :laughing:

 

[Beacon of Light]

So then these should work for my laser and the WF-138 charger.

Taken from Deal Extreme's website:

- Rechargeable LiFePO4 17340/CR123A 3.0V 350mAh Battery
- Life cycle: 2000 times (Traditional Li-ion: 500 times)
- Never explode or catch fire
- 100% Compatible with Disposable 17340/CR123A Batteries
- Working Voltage:3.2V and Peak Voltage: 3.6V
- Charging cut-off voltage: 3.6V
- Discharge cut-off voltage: 2.2V
- Please never overdischarge battery below 2.2V/cell
- You can safely charge these using the Ultrafire WF-138 Chargers set to the 3.0V mode
- Do not charge these with any lithium chargers for regular 3.6V batteries as they can have up to 4.2V charging voltage!
- Capacity: 350 mAh

Does AW or Ultrafire/Trustfire/Spiderfire make a higher capacity version of these cells. 350mAH is reminding me of the low capacity of 1990 NiCads.

 

[VidPro]

right the Li-Fe-Po batteries are a lower voltage battery, and work with the 3V setting on the UF charger and others.
Li-Fe batteries are a safer chemistry, and do not (yet) hold the same capacity that li-ions do.
Li-Fe batteries can replace a 3v throwaway battery , as the voltage is more similar to the throwaway.

the keys are the chemistry, the top charge voltage OF that chemistry, the chargers actual charge voltages.
Labeling the "3.6v" "3.0v" on the selector switches attempts to identify the battery your putting in, but it DOESNT well enough, and the Max charge voltage itself is what is more important. 4.2v (at 3.6 setting) ~3.8V (at 3.0 setting)

Li-FE charge is slightly less max charge voltage than the li-ion, use "3.0V" setting on many (but not all) chargers.

- - - - - - - - - - - - - - - - - - - - - - - - - - -

The regulated "3.0v" li-ion requires a charger that has a Higher voltage, to get enough voltage through the voltage lowering regulation.
Regulated li-ions can replace a throwaway battery without being so limited capacity.
Chargers for the Regulated li-ions CAN overcharge a non-regulated battery, and a "3V" Li-Fe , even though they can be "for 3v rechargable li-ion batteries" the voltage is for the Regulated ones ONLY. The charge voltage on these is ~4.8V
Regulated "3.0v" li-ion batteries can replace a 3v throwaway battery , as the voltage is more similar to the throwaway.

 

[Beacon of Light]

Well I bought a set of 10 of the Tenergy LiFe RCR123 750mAH 3.0 volt cells. Pretty good price on them considering the capacity. I bought 4 of the lower capacity ones at DX but that will probably take a while to arrive and I am anxious to test my laser, and I've had good luck with All-Battery before. They had a 15% off code I was able to use but their free shipping promotional code saved me more. I wish they had a better selection of flashlights like Zebralight or 4Sevens stuff then I'd be a more regular customer than just their batteries.

 

[mdocod]

Don't get excited about the capacity ratings. The true capacity of most LiFePO4 RCR123 size cells is going to be under 400mAH, as low as 200mAH depending on load and cell variations.

Eric

 

[45/70]

Yeah, like most Li-Ion cells, Tenergy seems to have gotten carried away with labeled capacity. LiFe cells generally only have a little better than half the capacity of LiCo's of the same size.

For DX's RCR2 LiFe cells labeled "800mAh", I get about 200mAh out of them at a 300mA rate on a CBA II, and my DX RCR123's (not labeled, but claimed "350mAh" capacity) I get around 300mAh, at a similar discharge rate.

Keep in mind though, that properly cared for (not over, or under discharged) LiFe cells are capable of 2-4 times the number of cycles, and also have a longer shelf life, as well. This helps to offset the capacity difference quite a bit, theoretically, you should be able to get considerably more Wh out of them, compared to LiCo cells..

Dave