11-10-2017 02:34 PM
11-10-2017 06:09 PM
Looks like the supplied power adapters outputs 65W: 20V @ 3.25A (https://download.lenovo.com/consumer/mobiles_pub/yoga920-13ikb_yoga920-13ikbglass_hmm_201709.pdf, page 60). The power bank you've linked looks to output up to 30W, but doesn't list the voltage / amperage.
11-11-2017 03:53 AM
I already use extra battery (zmi QB 820) and xiaomi 45w USB-PD adapter for my YOGA 920 now.
Original AC adapter is 65w, you know, but there is no problem.
Mysterious point i think is my USB-C voltage checker showed 15V for charging, not 20V.