XTAR 3100 mAh 18650 li-ion battery with PCB
I recently recieved two of these form szwholesale.com. Since it is based on panasonic cell it's gotta be a winner. We know they reccomend using a very low 2,5V cutoff for the protection PCB on these particular batteries. On these, discharging to 2.5V is deemed safe and even encouraged by the manufacturer. XTAR's 3100 mAh are pretty much onto these specs and employing the panasonic reccomended protection pcb scheme. The battery is pretty much like all the others. No fancy flames or other stupid things printed on them just the industrial/minimalist/professional type of sticker on a otherwise elegant black shrink wrap. "nipple" top so no issues fitting them in various application, dual/multiple serial config flashlights or just generally sizewise.
How does it perform? Well, i don't fancy expensive discharge equipment to test right to the last mA available. Plenty of others on our beloved forum that can do that. I decided to run them like i did with XTAR 2200 and 2400 and 2600 mAh verions a while ago. The cells were both charged using a XTAR MP1 charger. Strangely enough both left the charger at 4.22V. Since other batteries usually terminate charge at 4.19-4.2V on the same charger these seem to indicate they have very little internal resistance which is a good thing.
L2 body with XM-L drop-in powered by KD 2.8A (8x7135 AMC) driver. A 12x12cm PC fan blowing onto the flashligh, a timer and DMM.
I was able to finish the measurement with the usual batteries in under a hour and a half. Not this time. Turned out pretty hilarious. In the 5h+ watching the flashlight slowly dims my wife asked me quite a few times: Err, dear... what did you say you were doing, again? 2h are long gone dear...
Since resistance is futile i told her that i rather not bother her with technicalities and just let me do it. So how it did?
Splendidly. 2h of very good output, 1h of not so bright output and gradually on the 5h+ the emitter was moonmode bright. I even took some time to watch it painlessly. Took a measurement the battery and still it maesured 2,59V. Left it for an hour more to glow and it reached 2,58V. Switched to another light and left it on another 30 min and got 2,57V still. At this rate it would probably glow for 2 days more before reaching 2,5V and cutoff would kick. Too bad i really wanted it to see it shuts. The second sample went the same way and i went to 4h before quitting. No way of telling if these batteries at same level of charge have the exact same mAh capacity but it is pretty palusible. Compared to the next best thing i have the XTAR 2600 mAh with a quality sanyo based inner core this one provide considerably more juice.
Due to 2,5V cutoff, you are goona wait a loooong time before the protection kicks in. At least in a single 18650 flashlight. It's the capacity king atm. No problem with high current (tested up to 4,1A, a direct driven dropin).
Solid, normal sized, extreme capacity 18650 protected battery with good PCB and panasonic cell. Ability to discharge safely to 2,5V. This is one of the best in the market atm for sure. Price wise i believe XTAR will as usal provide some great pricing but without cutting quality. There is not much more to say. If someone is going for the XTAR S1 or other triple 18650 or other high drain application these should be on your shortlist for sure. Make no mistake it's not a trustfire, uranusfaire, fandyfire, ultrafire, pants-on-fire affair. This is a quality offering with a best in class panasonic cell in it along with a dedicated suitable protection PCB. For the budget oritented the price might seem a little on the high side. Well it can't be otherwise as these are as good as li-ion can get in early 2012 and as such comes at a cost.
Anyone wanting a best in class 18650 should look for these as it will be priced probaly less than other quality offerings or at least competitively. So no con's? Pretty much so if i'm realistic these do as much as you can possibly ask them to do today.
P.S: I want a dual serial or triple parallel 18650 light now!
They're gonna send you a green redcat with a black LED.