Review of / Measurement on Xtar WP2 II charger

[Colonel Sanders]

HKJ, you should do a review on Xtar's new SP2 charger. It is my new favorite charger with it's a ability to charge at .5a, 1a, and 2a which is selectable with the push of a button rather than using some cheap slider switch. I did some testing of my own and it seems to follow a pretty good CC/CV algorithm. It accepts anything from a 50mm length on up without spacers and can even handle 32650s. I tested current output and it does what it says it does. 2a pretty much stays dead on 2a during the CC stage, for example. More importantly, it does not overcharge even IMR batteries like some other chargers. It always terminates properly.

Also, the quality is very obviously way better than the Ultrafire chargers.

Very nice! :thumbsup:

 

[HKJ]

HKJ, you should do a review on Xtar's new SP2 charger.

I believe there is on in the mail, but I do not know when it will arrive.

 

[LEDAdd1ct]

I very much look forward to your review!

 

[HKJ]

I very much look forward to your review!

I picked it up at the post office today, it will probably be around a week before I am ready with a review.

 

[infinus]

I have one of these. My first one definitely was over charging (I hit 4.27 volts hot off the charger with a redilast and 4.25 with an AW cell). After giving the cells some rest time my AW's would settle to 4.23-4.24 and the redilast would sit above 4.25. I'm pretty sure the AW was hitting it's over charge protection. The Redilast overcharge is set higher. Yes, I used a professionally calibrated DMM for measurements.

I exchanged it (Went through Illumination Gear, Todd was great). My new one performs much better. My AW and Redilast cells both come off spot on 4.2 volts and after some rest settle to 4.18-4.19. I don't have the equipment to fully profile the charger but with the selectable currents, if you get a good copy it seems like a good charger. I'd love to see some curves from HKJ.

 

[Shadowww]

Hm, I just noticed weird thing about my WP2 II - when I charge anything Panasonic NCR18650A based, batteries get a bit warm (nowhere near "hot", just barely warm), but it charges at just 1A! With hobby charger (iC 106B+) batteries don't heat up at all even at 2.5A charging current.
So is the charger warming batteries up, by having charging circuitry physically very close to batteries, or are the cells source of heat, due to pulsing charging algorithm or for some other reasons? If it's for the first reason (circuitry itself gets warm, and warms batteries up) then why I only observe this with NCR18650A based batteries, and not any others (e.g. Xtar 2600mAh, AW 2200mAh etc)?

 

[45/70]

Hi Shadowww. I don't have a WPII 2, or any NCR18650A cells, for that matter, but I would imagine it's the charger electronics heating the cell(s). It's odd though that you don't notice this with other cells.

Perhaps it is the charge rate. The recommended charge rate for the 3100mAh cells is 885mA. I would think you could get away with 1A, close enough. I don't think I would charge these cells at 2.5A though. Most conventional LiCo 18650 cells have a recommended maximum charge rate of 0.5-0.8C. Maybe the Panasonic LiNiCo cells get too hot at these higher charge rates.

Dave

 

[Shadowww]

Perhaps it is the charge rate. The recommended charge rate for the 3100mAh cells is 885mA. I would think you could get away with 1A, close enough. I don't think I would charge these cells at 2.5A though. Most conventional LiCo 18650 cells have a recommended maximum charge rate of 0.5-0.8C. Maybe the Panasonic LiNiCo cells get too hot at these higher charge rates.

Yeah I know that going over 0.7C adds wear to battery, but when I need a fully-charged light and I need it fast, I have to make some compromises. I'd rather add some wear to my cells, than get left without any light due to not having enough time to charge cells fully at their recommended rate.
And, as I said, charging them at 2.5A (5A for pair, I charge them in parallel) on hobby charger does NOT gets them even warm. So I'm not worrying very much about it.

 

[45/70]

And, as I said, charging them at 2.5A (5A for pair, I charge them in parallel) on hobby charger does NOT gets them even warm. So I'm not worrying very much about it.

Well, that doesn't sound too bad. As long as you understand that your cells probably won't last as long. It sounds like you know that so......

I'm still betting that the cells are warming up from the charger electronics, rather than the heat coming from the cells. Otherwise they'd be warming up when charged with your hobby charger. You already surmised that, anyway I agree. If it were me, I wouldn't go over 1A, but I understand your predicament.

Dave

 

[HooNz]

I purchased one of these a few months back and i'm very appy with it....

Yesterday i was charging 2 18650's on the 1amp setting and whilst i was waiting i was listening to some overseas broadcasts on Short Wave using the Drake SW2 , and i noticed i could hear the charger in the next room doing it's business faintly .

It was a slight buzz , a ON for around 2 seconds and then a quick OFF for about 1 millisecond or so , it went like this>


zzzzzzzzzzzzzz zzzzzzzzzzzzz zzzzzzzzzzzzz zzzzzzzzzzzzzz zzzzzzzzzzzzzzz

Funny , cheers , Paul ........

 

[Shadowww]

Coil whine, most likely. Quite common in such type of electronics.

 

[Norm]

It was a slight buzz , a ON for around 2 seconds and then a quick OFF for about 1 millisecond or so , it went like this>


zzzzzzzzzzzzzz zzzzzzzzzzzzz zzzzzzzzzzzzz zzzzzzzzzzzzzz zzzzzzzzzzzzzzz

Funny , cheers , Paul ........

Quite a lot of electronic devices generate EMI that can be heard on the AM broadcast bands right up into the HF spectrum.

Norm

 

[gopajti]

click images for higher res

 

[StandardBattery]

I needed another charger like I need another flashlight (or something like that). I bought this one because it seemed reasonable for the price; BUT REALLY just because it provided a USB output that I could power with my 18650 cells; this is really handy. I've long liked the 18650 for the size/power ratio and that there are several good suppliers so I have quite a few of them. This charger allows me to make use of them more in emergency situations as USB power is really the new standard for low-voltage DC power connections; so much is USB powered now. Mine has the new labeling for the switch like the image in the previous post, but the documentation still refers to the switch as a 'gear' with positions '0', '1', and '2'. Mine (from HG ebay vendor) didn't have the 12V cable, but I was fine with that as any standard one should work.

Mine came with the two spacers also shown in the previous post, and these two spacers can be joined into a single long spacer. The manual says this can be used to charge 10440 and 16340 cells, but the bottom of the charger does not list these cells. Of course it would charge the cell at 500ma, which would be a 1C charge-rate if the cell had a true 500ma capacity.

 

[DavidAD]

I have haad this charger for a while. I just received some Panasonic 3400's and tried to charge them. the red leds began flashing when the battery is installed. Has anyone else have this happen?

 

[StandardBattery]

I have haad this charger for a while. I just received some Panasonic 3400's and tried to charge them. the red leds began flashing when the battery is installed. Has anyone else have this happen?

See confusing manual. if selector is on 0 (usb output) and power is connected to charger. May be other conditions that generate this flashing. what is current voltage on battery?

 

[HistoryChannel]

Is it safe to leave 18650 batteries in the charger after it turns green? At that point it shouldn't be charging anymore right?

 

[HKJ]

Is it safe to leave 18650 batteries in the charger after it turns green? At that point it shouldn't be charging anymore right?

It has stopped charging, but there will be a small current (Enough to charge a battery in 3 years) or without power connected it will drain the battery in 8 months.
It is never recommended to leave batteries in a charger.

 

[HistoryChannel]

That's HKJ, I trust what you say so I won't keep the batteries in there anymore. Oops. Lol.

I've been reading up on all your reviews last couple day after I discovered your website. Is fascinating. Thanks for your effort and energy to give us all the information!!

 

[HistoryChannel]

One more question, is it safe to charge an 18650 3100 or 3400 mAH battery with 2 amp setting with the Xtar SP2? Which setting is best? 500 mAH, 1a or 2 a? Thanks again! I'm thinking of getting the Orbtronic kit with Xtar SP2 and 2 x 18650 3400.