Have you had a look inside?
The reason the WP2 was so unreliable is there was only the protective coating on the pcb preventing a short circuit. After a few uses, the battery terminals wore the coating away causing a short (and potential electrocution)
I do not have WP2 II, the problem is the newer SP2, but well, I think I don’t want to temper with the foam screw cover to open it up to have a look as u suggested to avoid warranty issue. Anyway thanks for the suggestion ~
It all came down that the right channel on my SP2 slot were not charging anymore.
So I took the risk & opened it up to have a look on the charger pcb, especially on the right channel area.
Found a SMD component near to C10 had sort of cold-solder, the left channel sides also not to my liking. (sorry, forgot to take photos)
Switched on my hot air gun with small round nozzle to correct it & wicked up extra solder, after satisfied & to my liking, time to close it back & have a try.
Surprisingly it was charging again, it also doesn’t blinks red/green after a charge anymore, no matter with 26650 at 2A or 18650 at 1A setting, great to actually solved it.
The other problem with the WP2 (and the WP6) was that they had to detect a voltage before they would charged, so would not charge a protected battery if the pcb had tripped. Luckily the MP1 didn’t have this problem, but it meant you needed two chargers.
Any sign of this with the SP2?
I’d tried many times with SP2 to reset tripped cells from AW RCR123 & UltraFire Blue Protected 18650, where WP6 II shown green light, or maybe I didn’t put those tripped cells long enough for WP6 II to reset it ?
Can you take a photo anyway? Want to see what are you talking about 
Has there been a lot of cases of shortcuts with WP2 II?
Looking at that picture I do not know how short can happen?
Any idea
I think this is what he meant……the battery terminal (that silver thingy as pictured) dug into the transparent PCB insulation coating after prolonged use and the battery terminal got into contact with the copper layers below the insulation coating and causes a short.
Ok, just checked now, WP2 II has pretty much same tabs and joints as pictured above.
But I’m just a little sceptic, whether those tabs will eat their way to PCB.
The reason is the positive tabs are inserted in to plastic case in “grooves” and they are pretty tight fit. They support tabs from back and from both sides.
I was a bit cautious when taking the PCB off since I thought it is still connected fro somewhere but it appeared to be just that tight fit keeping it still.
That is a very good point where this product could be made better but since those tabs are solidly kept in place by the body, I don’t see the short circuit a very obvious thing to happen.
It may very well be possible but I thought those tabs were more loosely there before opening this up…
If it was just the bare soldering keeping the tabs sideways, I would be a bit more worried. Soldering is IMO pretty rigid but the PCB can give a bit slack when you try to bend those tabs.
If you own one, take those few screws from back and see for your self and comment what do you think?
Got my charger yesterday…
Huge upgrade from my previous Ebay charger…
This review says 1A/2A when charging 18650s.
The user manual suggests 0,5 or 1A 18650.
I have AW 18650 2600mAh.
Rated at: “Max. Charge Rate : 2.6A” which is 1C.
Recommended I believe is around 0.8mAh?
I have “PANASONIC NCR18650B 3400MAH PROTECTED” from intl-outdoor.
Not sure what the exact charging specs are.
For li-ion batteries in general i believe i have read several times the recommended charging rate is usually 0,3-0,7C.
That leads me to these questions?
When i have good time, should I bother using 0,5A instead of 1A. Or just use 1A as my standard charge setting for all good 18650s? Maybe 0,5C for 2600mAh, and 1C for 3400 when the goal is maximum life…
Would 2A be okay if I wanted fast charging? Would you guys assume battery life would get noticeably worse if that charging current is often used??
Generally you are always safe when charging 18650 at 1A, but some 18650 can take a 2A charge current.
With LiIon it is always safe to use lower current, i.e. you can also use 0.5A.
The specifications says 1.6A form them.
Recommended charge rate depends on the actual battery, the 2900 and 3100 mAh batteries from Panasonic has 0.3C charge rate specification.
IMR can usual take more than 1C in charge current.
Generally 1A is a good setting for all the 18650 batteries I have seen the datasheets on, it is slightly to high for 2900 and 3100, but noting serious.
Generally you can use 2A charge rate (Except on cheap batteries), but it will wear the battery down faster.
Thanks for great answers!
…and for all your great reviews!
Question HKJ, is Xtar coming out with a charger with a digital display? I thought read this somewhere and it’s going to available be soon. Thanks in advance.
They have stated they do on their facebook page and also that it will be around 10 of January.
My WP2 II is dead with blinking red lights. A battery in the left channel causes the red lights to come on and blink. It reads 12 volts. The left channel stays green with a lone battery in it and does not charge.
Waiting to hear from Xtar. Don’t hold out much hope.
Thank you. I am tempted, but I have a dead WP II. It lasted 14 months. I use a flashlight as a blinker on the front of my bike. The charger was used at least 200 times with 2 batteries in it. I contacted Xtar with mixed results.
I have two of these. One is perfect, the other has developed an issue in the far right bay after about 3 months. 
The far right bay will go red/indicate charging when first inserting a low cell, but then goes right to green in 3 sec, without charging the cell. I might have caused this somehow. 
Bestvaping.net/Powerwholesale.net was selling fake Xtar SP2 chargers and other products. Police has made a raid to Bestwaping and impounded all the fake products, so I quess Bestvaping isn’t selling any Xtar products from now on.
I never thought that such would be on TV there..
But thats not what you want to hear about a seller thats trying to get a good reputation with all those cells..