Great breakdown of the real question as to how this is going to work.
My question is, since @vapcell_Dennis posted about this adapter back in January, has it been made available for purchase anywhere?
I typically just use the AC supply, but the adapter would be useful to power the charger from solar panels (or maybe a “Solar Generator”) in an emergency. Or maybe for travel to keep from having to carry the AC supply.
some days ago I saw the adaptor on AliExpress …
and on the homepage of the S4+ V3.0 they inserted “USB-C option launched” …
Seems to be this thing 
Unfortunately that one doesn’t say what the max current at 12 volt out will be. It says this:
So it says what it can do for input, but not output. Or am I missing something?
It also does not specify the barrel connector size.
It requests the highest current the PSU can deliver. If you have a very rare 12V 5A PSU and a 100/240W emarker cable it should get 12V 5A.
12V 5A is out of spec though (or rather, out of recommended specs) for USB-C. The docs suggest to only use 5A for 20V, and 3.25A max with lower voltages.
If I read it right, it can use the PD 3.1 spec for input so that will cover the 20 volt 5A input. I think that I am reading that you can set the output voltage. But won’t the output supply the current that the load demands. Up to it’s maximum capacity to supply current, right? That will be different, or at least might be, from the input voltage and current.
So I think we are talking about it from two different sides of the equation. In versus out. Or are you thinking it just negotiates the input voltage based on the output voltage selection and it can then provide (without loss ??) the max current that the supply can provide at that voltage. They suggest only using 5 amps at 20 volts from the supply. Maybe they mean to not draw any more than that at a 20 volt output. But the charger can take, what 5 amps at 12 volts (which is what the AC adapter is rated for). So this is strictly limited by what the supply can deliver?? So the device will negotiate with the supply for the max it can deliver at 12 volts? I guess it is rare to find a PD supply that will actually do 5 amps at 12 volts…and the device says it is not recommended to use it at that level even if a supply can be found to do it.
Sorry I am rambling a bit, just trying to understand what the adapter does. Maybe it is smarter than I think it is.
And we still don’t know if the barrel connector is compatible with the S4.
This adapter is a simple PD trigger. You connect it to a PD supply and it will request the voltage you set, at the highest current it can get, and output that through the barrel. It can not do any kind of on board conversion, current limiting, or anything else. Output voltage/power is what this thing negotioates with the PD PSU. Current “limiting” is performed by the PD PSU (hopefully 
) having a overcurrent protection and shutting off if its ratings are exceeded.
Compare the product pics with the thing Vapcell is selling, it is the same PCB. I did not post it as a recommendation to buy, but as an explanation what Vapcell is selling.
At this point we have 2 options:
Thanks for that. I wonder if this device supports PD 3.1 EPR mode… and what happens if you set 12 volts out and the supply doesn’t do it… As will likely be the case for newer supplies where 12V isn’t part of the specs.
Hi Dennis, it’s me … (again … 
)
as now is clarified, that the Vapcell USB-C adaptor for the S4+ does not convert other voltages into the 12V, that are needed by the S4+, as I first assumed, because the given data to me seemed to make sense only with this capability (the Vapcell P65 PD, that is shown together with the adaptor connected to an S4+, at 12V can only deliver 36W, but at 20V it can deliver the necessary 65W), this leads us to the next question … (sorry … 
)
does this adaptor necessarily has to be set to “12V” with those tiny little switches (they allow the settings 5/9/12/15/20V) ?
in that case the adaptor asks for “12V” from the PD power supply, in case of the Vapcell P65 PD that would mean 12V x 3A = 36W max. …
or can the adaptor be set to “20V”, in that case the Vapcell P65 PD could deliver up to 65W, which is declared by Vapcell to be the necessary power of a PD power supply for this adaptor to work with the S4+ …
but that of course would require the capability of the S4+ to work with a higher voltage input as well, not just with the “12V” of the original DC 12V/5A power supply …
Thank You (again … 
) !
Good question. Some of my chargers are marked to accept something like 10 to 18 volts… I use 16 volt supplies on a couple of them. But Vapcell does not mention a voltage range anywhere that I have seen.
yes, I thought of the Gyrfalcon S8000, that originally is equipped with a DC 12V / 4A power supply, but in the specs is mentioned : Input Power : DC 11-18V / 4A …
but like you I cannot remember a specification like that for the S4+ …
it’s just that I’m still trying to understand how this works … regarding the “65W” mentioned by Vapcell … and whether the Vapcell P65 PD makes possible “full power” with the adaptor connected to the S4+ … or more about half of the power …
not that I would need the “full power” … as I said, I’m just trying to understand …
Yes, this !
I have seen this plan in the picture, thank you. We are selling conversion head accessories, but the sales are not very good. This conversion head can meet the working needs of S4+chargers with a capacity of 60W 
In the future, vapcell chargers will eliminate conversion solutions and use PD3.0 65W or other adapters, USB-C to USB-C data cables to power the chargers, saving weight
Currently undergoing testing
in case of the new Vapcell SU2 as a product manager I, too, would have chosen a conventional DC 12V power supply …
for this “All in One Charge Expert” (advertisement) with it’s great features I would have chosen the most trustworthy and reliable power supply …
in the past sometimes we saw bad charging results, especially with NiMH, from chargers with USB-C power supply, which forced another brand to release a second version of a charger after a disastrous test by HKJ … this second version got the addition “Plus” in the name and got a DC 12V power input in addition to the USB-C input … at the following version of this “Plus” the USB-C input was totally removed …
nowadays this charger in it’s actual version, with an “S” in the name instead of “Plus”, just has a USB-C input again … maybe they have solved the problems …
and yes, maybe I am too skeptical about USB-C …
I know there are many fans of USB-C power supply out here …
o.k. … but how this technically should work in detail still remains unanswered …
but o.k. … the S4+ in my opinion is best provided by the original power supply anyway …
in case of the SU2 with it’s half power requirement of 30W it would be easier to find a 12V trigger cable / adaptor solution, because 12V / 3A = 36W is not a problem …
Isa it very expensive/effortful to have a regular 12V input and a USB-C input?
Yep, not to mention some other chargers from this one brand, the one you mean was not the only one. And anotherbrand have/had also strange behavior with USB-C-power-supplies
However, my NC1500 don´t have this problems (but don´t use QC/PD), the Nitecores with µUSB and QC also not, so I think it´s possible to charge NiMH also with USB 
That has nothing to do with it having USB input though, just a flawed design.
I personally do not buy anything that does not have a USB-C PD input option, whether exclusive or next to a 20V barrel jack does not matter for me. More options are good, I guess.
Apart from being able to use it with multiple PSUs, and not having to carry dedicated PSUs on the go, it is also way faster and easier to source a decent quality PD PSU than a good (encased) PSU with a barrel jack.
12V + PD is a bit more difficult. 20V + PD is pretty easy. Main difficulty is, it should be able to work with 5V/9V/15V only PSUs too, which complicates things… But if the PD and barrel jack have the same max voltage, it’s easier.
I think 12V is possible with (almost?) any PD-power-supply, not sure about 20V.
But 12V 5A (Standard-PSU of Vapcell S4+ and LiitoKala Lii-600) is hard to find and not PD-specs?
12V is not part of the USB-C PD specifications anymore, so modern PD 3.0+ PSUs will not be able to offer 12V unless requested via PPS (which needs separate negotiations). Some manufacturers may still offer 12V, but are not required to anymore (and so most won’t).
My best featured , most flexible, most accurate and most used chargers do not have USB inputs at all. I would really restrict my options if I limited myself to only chargers having USB power input. I would be stuck using inferior chargers (at least with what is currently available) if I did that.
Of course I also have a few different chargers with USB C power inputs. I just use them for travel or when weight and/or space is a concern.
Having the right tool for the the required application is something I live by. Putting restrictions on the tools I use due to simply power input options just doesn’t make sense to me.
To each their own I suppose…
