Noob question about wiring a charging circuit...

[Artifex75]

I am a noob, but I aspire to be better.

So, I come to you with a question. How do I wire this:



Into this:


When I'm running two 3.7v lithium ion batteries? Is it even possible to passthru that circuit for usb charging? There's an enclosure that I'm itching to use, but it's not conducive to daily battery removal. If not that charging circuit, is there a better one to use?

Teach me, oh learned ones!

 

[retird]

Are the batteries in parallel or series?

 

[rolf]

artifex75
that is the same board I used in a couple of mods ..works nice for me ...your batterys must be in parallel 3.7 volts .you canot charge 7 + volts with it.also I would put a pt fuse in either the pos or neg leg .

 

[Artifex75]

Okay, so I can wire them in parallel easy enough, but can the TI chip convert that to a 5v output or do I need to have them in series in order to get anything over 3.7v? Is there a 7.2v charging board or would that be impossible with a 5v usb input?

 

[retird]

Which TI chip do you have? Is it a "buck" or a "boost" regulator?

 

[Artifex75]

It's the PTR08100W... I'm assuming that the buck reduces voltage while the boost increases? I think it's a buck in that case.

 

[retird]

Yep it is a "buck" so the batteries will need to be in series to work and NO the usb charger board cannot be used in this configuration....you can't charge 3.7 volt batteries in series........

 

[Artifex75]

Okay, so would this be a better choice for something like this...

DIY Power Bank 3 7V 5V Voltage Step Up Boost Board Kit w LCD Screen Display | eBay

It seems as if I can wire multiple batteries in parallel and still get 5v output with USB charging. Is there a better boost regulator out there?

Edit: Never mind, there's a limit of 4.2v input on that unit.

I pretty much just want a 5v setup with multiple batteries and an internal charger. What if I put in a port to connect a higher voltage ac charger, like one for hobby batteries or something of that nature?

 

[dr g]

By the time you jump through all those hoops you might as well have started with a better board.

 

[Artifex75]

By the time you jump through all those hoops you might as well have started with a better board.

What board would allow for the onboard charging of multiple batteries? Does the DNA20D allow for it?

By the time I spend $50 on the DNA20D board and everything else, I may as well get an Innokin iTaste MVP2. Is there a less expensive option?

 

[cadcoke5]

You might consider wiring a switch that changes between ON and OFF with the ON wired so that the batteries are connected in series. Then, the OFF is wired so that it connects the batteries, each separately to its own charging circuit.

It may require a Four-Pole, Double-Throw... a 4PDT. Here is a link to one, but it certainly is not a small switch at It is 3/4" wide by 1 3/8" long.
It is digikey part SC1821-ND. For some reason my pasted URL was not considered valid.

Here is a quick sketch of how the poles might be connected.


-Joe Dunfee

 

[retird]

You might consider wiring a switch that changes between ON and OFF with the ON wired so that the batteries are connected in series. Then, the OFF is wired so that it connects the batteries, each separately to its own charging circuit.

It may require a Four-Pole, Double-Throw... a 4PDT. Here is a link to one, but it certainly is not a small switch at It is 3/4" wide by 1 3/8" long.
It is digikey part SC1821-ND. For some reason my pasted URL was not considered valid.

Here is a quick sketch of how the poles might be connected.
View attachment 260634

-Joe Dunfee

The rating of the contacts of this switch is only .5amps DC.............not near enough for the output current needed for vaping.....

 

[breaktru]

I use a 3PDT switch in my MCU mod running 2 Li-Pos in series and charging them in parallel: 3PDT Schematic

 

[dr g]

What board would allow for the onboard charging of multiple batteries? Does the DNA20D allow for it?

You will need to charge the cells individually (or in parallel) somehow.

By the time I spend $50 on the DNA20D board and everything else, I may as well get an Innokin iTaste MVP2. Is there a less expensive option?

Not the same class of device.

 

[Artifex75]

Yeah! Now that's what Willis was talkin' 'bout.

I knew it was possible, my brain just wasn't going in the right direction. I'm off to fasttech to hunt down some switches, unless there's a better site? Is this something more easily found on eBay?

 

[cadcoke5]

I can see a potential problem with using a single charger and charging batteries in parallel. If one of the batteries have an internal short, then the other battery is going to be able to push current through it without any restraint, other than what resistance the bad battery still has.

I did actually find some high current switches with 4 poles, but they are so large that they aren't usable.

Originally I though that an electronic switch would solve the problem of the .5 amp limit. But, now I realize it would not, because the 4 pole switch has to provide the power to the electronic switch itself.

Thanks for catching that error.

-Joe Dunfee

 

[cadcoke5]

I think I found the solution. But, I can't seem to find it in 4-pole, nor a small enough size.



-Joe Dunfee

 

[kaddigart]

I think I found the solution. But, I can't seem to find it in 4-pole, nor a small enough size.

View attachment 260790

-Joe Dunfee

Awesome, combination APV and execution device. Or maybe you live near a train yard?


Seriously though, it seems like I read somewhere about somebody using an On/Off/On type switch...not sure about the technical designation for that, I'm still learning myself. 3P3T?

 

[breaktru]

No, 3PDT as shown in my link in reply #13

 

[kaddigart]

No, 3PDT as shown in my link in reply #13

Guess that explains where I read it before...

I just re-read it on your forum - that box is crazy complicated (for me anyway). Forgive me if this is a dumb question, but that switch along with the charging circuit would be wired into the rest of it where? What I mean is, say I wired the basic 5v mod guts (instead of the OKR-T6) on one board and the charging circuit on another. Could the latter just be wired in somewhere interrupting the other circuit between the batteries and VIN on a regulator?