CR2's and charging

[dagored]

I am venturing into the smaller lite area. CR2. I have purchased a JIL CR2 Ti for my birthday. Now, fuel for the lite.

I have searched the forums and nothing found with a definite answer.

On my own, I have come up with the following and would like some of the veteran people to chime in.

First I looked at Lighthound, of course, and found the following:
http://www.lighthound.com/Ultrafire-36-volt-or-3-volt-RCR123-Lithium-Battery-Charger_p_2270.html

Would that do RCR2's with a spacer? Like these:

http://www.atbatt.com/product/19947.asp

It apparently can be switched to 3V.

Limited to 3V according to Warren and that is what the lite is rated.

Should I just stick to primaries?

 

[malow]

I'm a newbie entering on cr2 rechargeable also.

i will also using a "3v charger" with magnets for charging.

example here

2 things to look for is a battery with "native" nominal 3.0v (max 3.6v/3,7v), and if the charger does not have a current higher than 1C*.

i will use on "very-low power" devices, i don't "need" in fact cr2 rechargeable's, but i will do because i can

what is the maximum voltage of JIL CR2 Ti? primary CR2 came with 3.2v, RCR2 should be right after charge 3.6v/3.7v

just my noob 2 cents

edit: if battery chemistry is LiFePO4 (probably), it can handle up to 4C charging rate.

 

[dagored]

I'm a newbie entering on cr2 rechargeable also.

what is the maximum voltage of JIL CR2 Ti? primary CR2 came with 3.2v, RCR2 should be right after charge 3.6v/3.7v

just my noob 2 cents

Jil CR2 max volt is 3.0. I can find chargers and batteries, but many are 3.6/3.7v. I do not want to fry this light. That is why I listed both the charger and batteries I had found. They seem(cross fingers) to meet the specs.

 

[malow]

Jil CR2 max volt is 3.0. I can find chargers and batteries, but many are 3.6/3.7v. I do not want to fry this light. That is why I listed both the charger and batteries I had found. They seem(cross fingers) to meet the specs.

i believe it can handle more than 3.0v, or will be damaged by primaries CR2.

but also does not grantee 3.7v rechargeable... well.. it should handle. but...

opening the flashlight, can you see the driver? IC of the driver? so we can find max voltage from specs.

 

[dagored]

i believe it can handle more than 3.0v, or will be damaged by primaries CR2.

but also does not grantee 3.7v rechargeable... well.. it should handle. but...

opening the flashlight, can you see the driver? IC of the driver? so we can find max voltage from specs.

I will not have the light until next week, looking for the extras now. Would this help you:?

http://www.candlepowerforums.com/vb/showthread.php?t=243062

and this:

Titanum Keyring Light
* Product name : J2
* Spec.
- CR2
- DD : Direct Drive
- Titanium
- XR-E Q5 WC
- McR17-XR

 

[malow]

"Take note that the Jil J2 cannot use 3.7V Li-Ion batteries , at least not for a long run;"

"- DD : Direct Drive"

mmm... no driver... it means the led CAN handle 3.0v bat (max 3.7v), but, i don't know how current will be handled.

i think my knowledge end here... lets wait for experts

edit: led is a Cree XR-E Q5, some people have sucess in direct drive. so may work fine with CR2 rechargeable's.

 

[45/70]

A few things you guys need to know about 3 Volt Li-Ion cells.

Before the advent of small (as we use in lights) LiFe cells, there were only LiCo cells that had diodes incorporated within the cell, to in effect, reduce the working voltage to somewhere between 3.2 and 3.6 Volts (ie. NOT 3.0 Volts). Due to the fact that these cells have diodes within their circuitry, a higher charging voltage is required to supply the 4.2 Volts to the base LiCo cell. This means that a proper charger for 3 Volt LiCo cells has to charge the cell to 4.4-4.5 Volts to achieve 4.2 Volts at the underlying LiCo cell. It's important to note here, that charging a LiFe cell in one of these chargers, may not be so dangerous, but charging at this voltage level will surely damage the cell, more than likely sooner, rather than later. Charging a 3.7 Volt LiCo cell in one of these chargers will not only damage the cell, but very likely could go . Most 3 Volt LiCo's have a maximum discharge rate between 1 and 2C.

Most of the 3 Volt Li-Ion cells you see around nowadays are LiFePO4. These cells supply a very similar voltage under load as the 3 Volt LiCo's, between 3.2 and 3.4 Volts (again, Not 3.0 Volts). LiFe cells require a lower end voltage than LiCo 3.7 or 3.0 Volt cells. The end voltage is about 3.6 Volts for LiFe and chargers are usually rated 3.6-3.8 Volts, so these cells require yet another totally different charger. Most of the smaller LiFe cells that I have, or have seen available, are rated at a maximum discharge rate of 1C, not very high. While A123 Systems LiFe cells (and others) are rated at 30C discharge and beyond, again, most CR-2 and CR-123 LiFe's I've seen, are not. Personally, I've been running 350mAh LiFe 123's sometimes, at 3C, but I don't expect them to last 2000 cycles either. It's probably pertinent to add that putting a heavier current load to a LiFe cell than it is designed for, is not nearly as dangerous as doing so to a LiCo cell.

So, there are three different types of chargers involved with Li-Ion cells. In some cases, you can use the wrong charger and get away with it, the cell just won't achieve full charge. In the worst combination's, you will either damage the cell, or run the risk of "venting with flame". You have to use the proper charger for the chemistry/voltage of the cell you are charging. If you're not sure what chemistry you're dealing with, contact the dealer or manufacturer.

As far as whether your light can use a certain cell, you have to find out exactly what chemistry the cell is, and then I would contact the manufacturer of the light, and ask them if that is a suitable solution. Then, make sure you purchase the proper charger to charge that chemistry/voltage cell.

Dave

 

[dagored]

Dave,

Thanks, even I understood that, however, I am still looking for RCR2's equal to but not greater than 3.2, with a viable charger.

I know that 3.6 or > are not recommended for my light.

Again, if I can not find a suitable charger with matching cells, I will go the primary route.

As stated in my first post, a search for CR2, CR2 charger, etc, gives very little useable info for my situation. Chargers with spacers are easy to find, but not the batts.

 

[45/70]

OK, dagored. My post was a bit long winded, but I see a lot of misunderstanding about the various voltages and chemistries of, in particular, the smaller li-Ion cells. People not understanding why their cells don't seem to charge etc. when the problem is, they are using the wrong charger. I guess my main point directed at you guys, is that both 3 Volt LiCo and LiFe cells will be at a minimum of 3.2 Volts under load. That is to say, they will probably be over 3.2 Volts for a portion of their discharge. Maybe this would be a factor, maybe not. I was interested in a Jil back a few years ago. One of the reasons I didn't get one was the uncertainty of whether I could use rechargeable Li-Ion's in it. Some folks said no, and no, I didn't ever actually contact the manufacturer to find out.

The only LiFe cells I have are 6 of these and 8 of these. I use a WF-138 charger (set to 3.0 Volts, of course) which, maybe I got one of the "good ones", but seems to work very well.

The cell you linked to in your first post may be a good choice. They do not supply enough information, however. Their reference as to the cells chemistry, "Li-ion", is about like shopping for an automobile and coming across an add description describing the model as "car".

I suspect, but don't really know, that that cell is a 3.0 Volt LiCo. The biggest problem with the 3.0 Volt LiCo's now is I don't know of anywhere that you can purchase a proper charger for them. batteryspace used to have both 3.0 Volt cells, chargers, and a combination thereof. All they have now is the cells themselves. It is their chargers (2) that I use to charge my Powerizer and old AW 3.0 Volt RCR-123 LiCo cells.

With the exception of the LiFePO4 chemistry cells, 3 Volt LiCo RCR-2's and RCR-123's for that matter, are getting hard to find. I suspect that too many people stuck 3.7 Volt LiCo cells in their chargers and had bad results, or dealers just don't want to risk the liability, and that's why they're fading from the scene. The LiCo 3 Volts do have about twice the capacity of the LiFe's so, I for one will miss them.

If you really want to stay as close to 3.0 Volts as possible, I'd go for LiFe as, in my experience, at the start of their discharge, they run a little lower in voltage under load than the 3 Volt LiCo's. On the other hand, the LiFe's have a much flatter discharge curve than the LiCo 3 Volts, so it may work out about the same in the end.

Dave

 

[Illum]

I'd give sabrewolf's charger a look if conventional chargers designd for bigger batteries have a charge rate much too high for CR2s
http://candlepowerforums.com/vb/showthread.php?t=240090

he has a version that charges at 100ma

 

[45/70]

I'd give sabrewolf's charger a look if conventional chargers designd for bigger batteries have a charge rate much too high for CR2s
http://candlepowerforums.com/vb/showthread.php?t=240090

he has a version that charges at 100ma

A typical "Postmaster" response, ie. he didn't even read the thread. lovecpf

Watch out for those asterisks guys, one makes you suspicious, two, well.....

Here is a link to one of the CBA tests I did for the six DX RCR-2's, on DX's site. They don't refer to these cells as LiFe, but I'm certain they are.

Dave

 

[ShineOnYouCrazyDiamond]

Doesn't look like you guys ever really came to a cell conclusion here. So just adding a bit of my experience to help if possible.

I purchased the AtBatt RCR2 cells with their charger and they work just fine. Never had a problem with them at all. On Aeon I get about 25 minutes and on EZCR2w I get about 22 minutes.

I also have a few of the UltraFire RCR2 800mAh cells (which are nowhere near 800mAh obviously) and they give just a little more time than the AtBatt cells. On Aeon about 30 minutes and about 25 minutes on EZCR2w.

Mind you all time is on the Highest possible setting run straight through with a fan for cooling if needed. The EZCR2w draws about 600mA on these cells so under load you can figure the UltraFires are around 250mAh under load and the AtBatt are about 220mAh. The AtBatts are closer to a "true" specification and about what you can expect from these tiny cells.

I charge both the AtBatt and the UltraFire cells on the AtBatt charger with no problems. I am assuming they both use LiFePo4 chemistry.

I've also picked up some of 3.7 RCR2 size cells from LightHound. They work great in the EZCR2w but the Aeon can't handle them. Haven't done any runtime tests because pushing ~800mAh through the EZCR2w things get hot quick.

 

[45/70]

I also have a few of the UltraFire RCR2 800mAh cells (which are nowhere near 800mAh obviously) and they give just a little more time than the AtBatt cells. On Aeon about 30 minutes and about 25 minutes on EZCR2w.

The link in my last post is the CBA run I did on those same UltraFire cells. Granted those cells only had a couple cycles on them, but I seriously doubt they would ever go much over 200mAh, especially @600mA. The tests were run @300mA.

Do you know the end charging voltage of the Atbatt charger? It could be the AtBatt cells are LiFe, I was just speculating.

You should know that just because you can charge your UltraFire CR2's on that charger, doesn't necessarily mean the AtBatt cells are LiFe. You can charge LiFe cells on a higher voltage charger (either a standard 4.2 Volt LiCo or a diode reduced 3 Volt (4.4-4.5 EOC) LiCo charger), they won't go , but the cells cycle life will be greatly reduced.

Either way, both these cells seem a good alternative to using primaries, in most applications. It would be good to know that the proper charger was being used though.

Dave

 

[dagored]

ShineOnYouCrazyDiamond,

I found the site and batteries. They are out of stock, but the specs look great. Don't wasnt to the light.

What charger did you purchase? Here is all I can find on their site:

http://www.atbatt.com/product/21659/digital-camera/ricoh/prego-zoom-115-date/charger

 

[ShineOnYouCrazyDiamond]

The link in my last post is the CBA run I did on those same UltraFire cells. Granted those cells only had a couple cycles on them, but I seriously doubt they would ever go much over 200mAh, especially @600mA. The tests were run @300mA.

Do you know the end charging voltage of the Atbatt charger? It could be the AtBatt cells are LiFe, I was just speculating.

You should know that just because you can charge your UltraFire CR2's on that charger, doesn't necessarily mean the AtBatt cells are LiFe. You can charge LiFe cells on a higher voltage charger (either a standard 4.2 Volt LiCo or a diode reduced 3 Volt (4.4-4.5 EOC) LiCo charger), they won't go , but the cells cycle life will be greatly reduced.

Either way, both these cells seem a good alternative to using primaries, in most applications. It would be good to know that the proper charger was being used though.

Dave

I don't think it's clear what the chemistry is on either of the batteries but I thought that unless there was protection or votlage reduction circuitry on the batteries that all chemestries of LiIon except for LiFePo4 were 3.7v nominal. And the RCR2 batteries are too small for any protection circuitry to be in place on them - either brand.

There is an interesting little sticker applied to the AtBatt CR2s that reads "1Wh". Now I'm not sure if that is supposed to mean 1 Watt-hour or not because it differs from the 3.0v x 250 mAh = .75 WH rating on the battery.

I don't have the equipment available to do more scientific testing. Also forgive me if my battery chemistry information is weak. I am more attune with LiPo technology and some LiMn as it applies to battery packs for RC vehicles. Still kinda new with the LiIon technology.

ShineOnYouCrazyDiamond,

I found the site and batteries. They are out of stock, but the specs look great. Don't wasnt to the light.

What charger did you purchase? Here is all I can find on their site:

http://www.atbatt.com/product/21659/digital-camera/ricoh/prego-zoom-115-date/charger

That is the charger I purchased and it seems to work pretty decently.

 

[HarveyRich]

I've been using the Ultrafire 3/3.6v charger on both 3v and 3.6v Cr2 rechargeable batteries and don't seem to have a problem. On 3v, the charger stops the voltage at around 3.4v which might be a bit on the high side. At 3.6v, the charger stops charging at 4.2+v, which is about right. If you monitor the charging process you come out OK. The charger is listed at 250 ma, which seems about right from what I've read on CPF. This should be at or less than 1C for all the Cr2 batteries, even if the Ultrafire ar not really rated at 600 or 800 mah.

BTW, my Nitecore EZ Cr2 flashlight, which I received about a week ago, seems to work just fine on both 3.0v and 3.6v rechareables.

 

[Bullzeyebill]

Most of the CR2 lights running direct drive that we CPF'ers see run fine with RCR2, 3.6-4.2 volts. You could charge a cell up to say 4.0 volts and that would even be safer. At 3.2 volts from a CR2, you are barely attaining the vf of the LED. Granted, sustained running at 4.2 volts starting, may be hard on the LED, over time.

Bill

 

[Christoph]

I have a Jil Ti cr2 and the UF 3 v cr2 cells being talked about and I tried them in it. I measured a starting current at around .45a. With the absence of a proper heat path I would hesitate to let that much current pass.The primary cell I checked in it started out at .25a. Both of course declining but I wouldnt try and drive it that hard at least till I have upgraded it :devil:
C

 

[dagored]

Thanks Chris, primaries only for now. Keep in touch about an upgrade.