I noticed that, but Werner grabbed it off cnqg. They show different charge rate specs.
Other than they they look the same though.
The reviewer on IO says his was labeled 1000mA. Found it actually did 650-670mA. He also reports that it continues to trickle charge after light goes green. Overcharges.
If your green light fades in or flickers on thats a big sign there is no actual charger chip inside.
So if you just stack two boards you get double the charge current? Nice!
For 26650’s and 32650’s I’d probably stack 3 so I could charge at 2.55 amps 
-Jamie M.
Dang, guess ill have to keep a close eye on it.
Bort seemed to get his from IO & the behavior he describes is what you’d see in a ‘charger’ with no controller chip, like Werner’s pictures. Charge controller chips can cost very little. If its missing, well, to put it nicely, it was made extremely cheaply. That doesn’t go together well with AC power & sold direct from china.
If you have a soldering iron you can put a usb tp4065 board in it pretty easily. Solder 2 wires.
If you want to do 3 boards I would check the termination voltage on each board before connecting them together. Reason being that the highest termination voltage is what your battery will get. More boards, higher chance one will be a bit high.
All charger IC chips vary from one chip to another in termination voltage. ±1.5% for this chip.
I know it might clear enough how to connect them but just to be sure (and for anyone who comes along):
Connect the “IN+” together between the boards. Connect the “BAT+” to “BAT+” and “BAT-” to “BAT-”.
“IN~~” does not actually need to be connected, it runs straight through to BAT~~ so that has already connected it.
Only plug in one usb jack on one board. Do not connect two different usb sources. Don’t use a pc for usb power. 2 boards will likely need over 2A usb power, 3 boards 2.75A (some power is lost in constant current charging).
I’d recommend a nice $1.50 d cell battery holder from ebay. Connecting your li-ion battery backwards will burn the chips at the very least.
~ edit ~
Since they come in mini usb or micro usb use one of each and you can use either cord. :bigsmile:
Would this be connected to the stock board or on its own?
If the idea is to get rid of the stock board, is there anything in particular to pay special attention to when replacing the old board and installing the new one? (If I were to do 1 I would likely use dual while I’m at it, 26650 on my i2 is starting to drive me a bit crazy in how slow it charges.)
Hmm, thinking of what would be easiest. I don’t have one of these myself so I’m using Werner’s pics
Couple ways to do it. You wouldn’t be using the stock board at all anymore. Don’t actually need it in there & it takes up room but the positive terminal that the battery presses against is soldered to the stock board. If there would be enough left to still solder to you could just cut it off the stock board.
You can desolder it by heating the solder joint underneath while pulling the terminal with pliers. Then the stock board could be tossed. Pos & neg from the tp4065 board would be soldered to the positive terminal & the slider.
If you don’t want to desolder the terminal instead you could cut a couple components off the stock board & there are two spots you would solder the pos & neg from the tp4065 board. Not as, I dont know, clean but almost seems easier in a way.
Ok, its a wee bit more then “solder two wires”… :zipper_mouth_face: Didn’t really think of the steps for the positive terminal. I look at it I see two wires. 
I’m happy to provide any help I can.