Review: Xtar WP2 Mark2 - 18650 2 bay charger

For review I have the WP2 Mark2 charger from Xtar , and after two days of testing I just might have some good news for the folks out there looking for a 18650 battery charger .

XTAR WP2 II 14500/ 14650/ 17670/ 18500/ 18650/ 18700/ 10440/16340 3.7V Li-ion battery charger

Charging qualifications and structures
Operation Temperature: 0~40℃
Input AC: 12V DC / 1000mA
500mA CC Current: 500m A±5%
1000 A CC Current: 1000m A±5%
Cut-Off Voltage: 4.2±0.05V
CV Cut-off Current: <100mA
Standby Current: <20.0m A
TC Current (Battery Volt 2.0~3.0V): 80±20m A
Auto Recharging Threshold Value Voltage: 3.9±0.15V

USB Discharging qualifications and structures
Operation Temperature: 0~40℃
USB Interface Output Floating Voltage: 5.0V
Output Floating Voltage Ripple: <120 mV
Reactive Current: <10m A
Maximum Output Current: 500mA
Battery Output Cut-off Voltage: 2.80±0.15V

The MK2 is very close in appearance to the first version but there are some minor changes , and the most obvious are the changes to the contact tabs , both positive and negative . They both look to have been beefed up and extended [ re-shaped ] to make better contact with the battery or simply to be stronger , Im not sure , maybe both , but I have to say I never found either an issue with the first one .

But what these minor changes do in the MK2 is is tighten up the fit of the 18700 batteries , from room to spare in the MK1 to a some what snug fit in the MK2 , now its not something to worry about , unless you own even longer batteries than the Xtar 18700 cells .

Now lets talk about the charger ..

On the front is a 3 position switch , if you dont want to use the USB feature [ 5volt power ] then you only need to concern yourself with position 1 and 2 [ position 0 is for the USB ] . Position 1 gives you 500mA charge rate , and position 2 gives you 1A charge rate . The first thing I tested for was if charging more than one cell affected charge current , and Im very glad to say that the case is No . Whether you charge one or two cells does not affect charge rate , nor does it seem to make the charger run any warmer , giving me the feeling it can handle 2 cells and 1A for each channel with little trouble .

Lets look at how the charger behaves : Lets start with the 1A setting

I was using two batteries Bat-1 @ 3.03v and Bat-2 @ 3.4v to start ... Both channels were doing 1A

I was monitoring the charge rate as the batteries charged , and at 3.84v the charge rate had dropped to 800mA

At 3.99v the charge rate was down to 500mA

At 4.07v it was down to 300mA

At 4.12v it was down to 140mA

And the charge terminated @ 4.14v [ tested battery voltage ]

Now lets see the 500mA results :

On the 500mA setting , the charge rate was 520mA , and it stayed there right up to 3.9v [ tested batt voltage ] and dropped to 400mA at 3.99v , 290mA at 4.07v and 160mA at 4.12v and the battery terminated at 4.14v ...

Battery termination :

I have charged over a dozen cells [ 18650 ] in two days and they all terminated at an average of 4.15v [ tested battery voltage ] .. Lowest was 4.14v and the highest was 4.16v .

Standby Current :

Now this charger does not fully turn of , but I did only measure some 0.11mA current when the charger completed the charge . Lets put that in perspective , that's 11% of one mA . So worrying about when you pull the battery should not be an issue ..

With termination voltage around 4.15v and a standby current of 0.11mA , it would take 10 hours to dump 1.1mA into the cell , and that leads one to call this a safe charger . [ based on this charger ]

Some pictures :

Conclusion :

My charger came with the 12v cigarette power adapter , a adapter plug for the power supply [ for Australian outlets ] and the charger , and the user manual . I have to say this is a solid performing charger , with two charge current options , it really does help speed up the charge cycle [ 1A ] , it holds higher current longer [ again shortening charge time ] . The overall build quality looks to be excellent , and improved upon over the Mark 1 , which is nice to see [ A company try to make a better mouse trap ] . The charger still uses the pulse style charging [ similar to WF-139 , WF-188 ] where it charges and then stops to check the battery and then continues .. [ Hence the term pulse charging ]

The open voltage was 5.1v on one channel and 5.4v on the other [ if this makes any difference ] ...

With some chargers advertising 1A charge rate , they can only sustain it with one battery and as soon as a second cell goes in the charge rate halves , well not with the WP2 MK2 , with two cells , it not only maintains the charge rate , but also there is no sag from the load of the 2nd cell , now that's nice .

Termination is between 4.14v and 4.16v , and some covet such chargers as it may extend the service life of batteries by not pushing the very max charge possible into them . And for some one that uses there batteries hard , say a security person who may do night shift and use a flashlight a lot , and recharges daily putting a lot of cycles on a battery , extending a batteries service life can make good sense , and for the average Joe looking for as safe as possible a charger ? , the Xtar WP2 Mark2 makes the grade with room to spare .

5v USB

Now I don't personally have much use for the 5v USB port , but then I thought , don't I have a USB AA charger ..

It took about an hour and fifteen minutes to charge a single AAA from 1.11v [ rested but fully depleted ] to 1.36v .. This could be a nice feature if you have a device you wish to keep powered [ VIA USB ] or in this case , charging a AAA battery ..

18650 was at 4.15v , AAA was 1.11v , on completion the AAA was 1.36v and the 18650 was 3.9v , this was a older Ultrafire 18650 with a capacity around 1500mAh

Only the left channel gives the USB port power , select 0 on the 3 position switch at the front of the charger and then plug in your device of choice , and the limiting factor here will be the battery capacity of the 18650 [ or battery chosen to power the USB port ] . This could be handy when out camping , especially as cell phones for example have become a very important life saving device , that no one should be without , when venturing out where help is hard to find . The USB function is handy , but lets not forget , this a a nice solid charger , and I ran it hard for 2 days , and I saw no reason not to recommend this charger , in fact , if this sample is the norm , then I would highly recommend it , especially to first time Li-ion users who may not own a Multimeter , or be aware of Li-ion procedures .

I will continue to use this charger as much as possible , ATM I have run out of batteries to charge , but if anything should change , I will do a update .

That is what I am talking about! Great review.

This charger packs a lot of features for a good price.

I just buy other two charger (a TF and a XTAR) but i have to admit this is really good. The USB output is quite interesting for me.

Today I just received the WP2 I ordered from the manufactor @ ebay... Well... its was advertised as WP I but I received Version II :) So I can forgive, that they set the status to "sent" at first of august but in real they shipped it at 12.08 -.- (tracking and label never lies ;) )

It really looks nice so far and I have the first batteries in charge... @old is it normal, that the charger gets really hot at the bottom of the top?

yes , there is a bit of heat coming from the components ...

I either lay the charger on its side or standing [ leaning against something ] so that there is better convection cooling [ air movement ]

One side of the charger gets warmer than the other . Its not excessive , but you dont want to block the cooling vents on the bottom

Okay :) As far as I can see its only @ 1A.. When it goes down @ 500mAh it gets "cool"

Excellent review as always, Matt ;)

"The charger still uses the pulse style charging [ similar to WF-139 , WF-188 ] where it charges and then stops to check the battery and then continues .. [ Hence the term pulse charging ]"

... and similar to WP1? Would be great to know if they just added USB port and 1A charge rate or improved charging performance as well. (can't see any changes tho, the same pulse charging and slightly high mA termination)

The WP2 V1 uses exactly the same charging method, but the V2 has much lower termination current. Both of the chargers stays with the valid parameters for LiIon cells as can be seen on the charge curves in my review.

I knew I had seen that review before :bigsmile: Thanks, HKJ (like your cell reviews very much, btw (and forgot about chargers). Keep up the good work ;) )

I haven't peeked inside as yet , but that would be my guess .. + the 1A setting does help lower the time it takes to charge a depleted cell ..

I your topping off a battery , it wont make much difference ...

Sounds like a good one.

Thanks for the detailed review as usual! Frontpage'd and Sticky'd.

I got mine. I paid $16.69

However, the car charger is not in the advised.

She did not state that a car charger was included, and it was not.

I see that the price has gone up by $3.....if you need a car charger, better look around.

Here is a link to what I did:

Price is higher now.....OH, chinese return to Capitalism!

That's the same seller I bought from got it for $16.00. Maybe the higher price includes a car charger (probably not).

Here's the working link.

Very good job and thanks for your effort. old4570!

I have WP6 charger and love it. Laughing

Charged ~15 Cells now (Himax, Trustfire Flames, XTars, Solarforce) and measurements few hours after charging show same results 4.16 to 4.18V

Thanks for the great review. I definitely consider the early charge termination an advantage, although a switch to select a slightly higher termination voltage would probably make for a nearly perfect budget charger. Does anyone know how to mod the circuit to do this? Ive been manually pulling my cells off the charger at around 4.16-4.17V. Its great to know that the new xtar takes care of that chore.

Does the WP6 share the same early charge termination characteristics?

In my experience, it does.

4.15v to 4.17v after resting.

Thanks, thats good to hear. Do you have the older version or the new one?

It is nearly the same, but my review copy had a higher termination voltage.

I have the new one.

I've been very pleased with the charger so far. I picked up a couple of 3x 18650 lights recently, and didn't feel good about balance charging cells on 2 different chargers....even though both chargers (Solarforce and cheapie DSD) would charge the batteries to within 0.03v of each other.

The Xtar charger is a good-quality unit, almost as nice as my lower-end MAHA chargers. The included screw-in adapters for other batteries is a great touch - I'd be surprised if others didn't follow their lead on this design.

I've charged everything from RCR123s to the extra-long Callies Kustoms 3100s on it so far, and cells with identical chemistry charge to within 0.01v- 0.02v of each other repeatably.

Sizewise, it's about two of the cheapie chargers side-by-side, yet does six cells.

Input is 12v 2A, so if you have a beefy car cord, you can probably charge cells on-the-go.

My only complaint would be that the negative springs feel a bit cheap/weak, but then again, not much spring pressure is needed to maintain contact....the charger is usually used on a stable surface. If I were to upgrade anything on the charger, it would be this - and I'm probably being a bit harsh, as the thing has performed as advertised so far.

Conclusion? This is a RECOMMENDED BUY !