As it says in the subject I am looking for a compact 2x18650 power bank that has quick charge 3.0. My perfect power bank would be something like the Tomo M2 (which is what I keep in my purse now) but with QC3 so I can get “fast charging” on my Samsung phone. I have looked on eBay and Fasttech, but maybe it doesn’t exist…
The problem is not a 18650 not being capable of the power output, there is simply not a market large enough for a manufacturer to invest money to develop a DIY QC3.0 powerbank board + Housing. And even if they did, it probably won’t work as efficiently as finished products. And if they manage to make it work flawlessly, I highly doubt the finished setup will end up being cheaper than a existing product.
BTW most QC3.0 devices are backwards compatible with QC2.0 (5/9/12V) chargers, so I would recommend looking into existing powerbanks that work great and are cheap, like the xiaomi 10,000mah 2. It has one of the best capacity-size ratio, can be found under $20.