Yes, indeed, most people do have power banks.
But some of us also have a lot of Li-ion cells and we like to go the extra mile.
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I am waiting for a IR tester to arrive in a few days and I will do some resistance comparisons.
I will also test the power bank function to know for sure if it works: what voltage and current.
I hope everything will go wellā¦ 
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I did a short test with my Vapcell S4 Plus V3.0 in the power-bank mode, with 4 brand new Molicel P28B 18650 batteries (only one storage charge at 50% - 3.7V since i got them) !
So i decided to check them out how they are after a few months in storage !
When i put them in the charger they were pretty good ( some of them was at 47% and some others all most 50%) after the ācharger readingā in a few minutes the charger started beeping that i had completed battery at 50%, so im good so farā¦ !
Then i plug them on the phone when it was 30%, and after the short test (almost 1 hour) the batteries are down to 30% and the phone up to 70%, so i stop it because i didnāt want to āforceā the batteries below then that !
So im pretty good with that, no problem, no smell, no heat, no nothing, everything is working perfectly ! Im pretty pleased with it !
Dennis, could you please confirm whether S4+ supports also 20v, which would be required for the āconversion headā to work for providing 60w? I donāt want to find out by trying.
Vapcell s4+ V3 and YR1035+ resistance tests:
Cell used: Wurkkos 21700 5000mAh
For Vapcell charger I measured several times (3-4) in each slot and set the lowest value.
For YR1035+ I only made 4 measurements.
Vapcell s4+ V3 (DC) Internal resistance measurements:
Slot #1 23 mĪ© (lowest)
Slot #2 21 mĪ© (lowest)
Slot #3 21 mĪ© (lowest)
Slot #4 22 mĪ© (lowest)
YR1035+ (AC) Internal resistance measurements:
Test #1 12.98 mĪ©
Test #2 12.98 mĪ©
Test #3 12.90 mĪ©
Test #4 12.95 mĪ©
What I observed:
- The measurements are more consistent if:
- Contacts are cleaned with Isopropyl alcohol 99%.
- Cell is twisted few times inside the charger.
- Bigger cells have better repeatability on tests (probably better spring tension and larger area of contact).
The repeatability issue lies in the charger zinc-nickel plated contacts.
At milliohm level, these kinds of contacts show their weaknesses.
Maybe some gold-plated contactsā¦ 
The power bank function of Vapcell S4+ V3:
I only charged my phone. No heat, no error, just charging.
From what Iāve read on the forums, it seems that the unfortunate cases happen mostly while charging power banks.
It seems like a bad USB handshake between certain models of power banks and the charger.
Voltage: 5.07V
Current: 1.38A
I hope they release a v4 with better algorithm for IR and better power bank function.
Until then, Iām happy with the charger for my needs.
Happy New Year!
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Vapcell measures DC IR, Yaorea measures AC IR.
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Yes, the YR1035+ uses 1kHz AC.
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Do you know how Vapcell executes the DC IR measurement? There are a lot of ways to test it and a lot of factors could be of influence.
Below is a bit of an older topic, but as far as I can tell still relevant, but there is a lot of information (and interesting discussion) on how certain things could be of influence. (And therefore getting consistent and repeatable results.)
From this post onward is the most useful/interesting information:
No, I donāt. Thanks for the link, interesting info.
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