For others trying to find how many charges you actually get from power banks, because it turned out to be not that easy to find, especially with all these variables (see below) and a lot of misleading comments/posts/review from people who are mistaken. Sharing is caring, so please add your devices in comments.
Some thoughts for other lurkers:
- Amper-hours depend on voltage, so 20000mAh (why not 20Ah, god damn marketing and our monkey brains) might differ from power bank to another.
- Watt-hours (Wh) might also be a lie, according to some reviewer even known brands might sin.
- On top you have conversion loss 80-90% roughly speaking.
I bought INIU 20000mah 65w mini P62-E1 for ~50$. It says it is 73Wh. I got exactly one charge 0-100% for my Steam Deck OLED (50Wh) while it being off.
It was as fast as wall charger and thing is small and weights 320g, which is perfect for me. Also design/surface is above what I expected. Included cable is crap and does not support 65w charging, don't ask me why. Steam deck will on repeat go full charging and then stop with that cable. I can recommend it I guess, but for sure there is something better, depends on discounts, too.
I still question myself why did not I try it before as it changed my quality of waiting on different places like public transport by large margin:
Try turn based games with Lemuroid (frontend for emulators on android). No gamepad required, always in your pocket, everything works out of the box.
I'm playing psp Valkyria Chronicles and it is great. Such games are perfect format for phone, as anything where reaction and precision is necessary needs gamepad. And you either need to own a retro dedicated handheld and take it with you, or (if you have one) take cumbersome Steamdeck like handheld, which is not feasible for 30 minutes ride.