hey homie, the post you replied to a few weeks ago was made in February of 2021 - it seems like you might not have noticed the date? It’s usually okay to start your own thread when a previous one fails to adequately answer your question, or when the prior discussion is left “incomplete” as I would say is true of this case.
Anyway, since homie never ended up getting back to the thread back in '21 I might as well chime in to say that I’ve run pretty much all of my SBC’s, including my Rock Pi 4C, using power from a random “USB power bank” that I bought on Amazon after reading some good reviews and doing a bit of research. I believe the important features to look for are:
- minimum 3 amps @ 5 volts output (careful here, TONS of these chargers from popular brands like, e.g., Goal Zero, only offer ~2 amps @ 5 volts)
- ideally you want to look for performance standards like “PD” and “QC 3.0” - these terms refers to specific “quick charge” protocols that essentially allow a device to give the power bank thumbs up to supply more than 5 volts, thus upping the total power delivery even if the amperage drops a bit. For example, you’d commonly find a 3 A @ 5 V power supply (~15 watts) w/ QC 3.0 compliant switching that can bump up to 2 A @ 9 V or 1.5A @ 12 V - both of which would supply ~18 watts in theory.
- USB-A output or USB-C output both oughta work just fine, just use the appropriate cable obviously.
*For capacity, you probably want a minimum of] ~10 amp-hours @ 5 Volts, or 50 “watt-hours” (they will commonly advertise in milli-amp-hours, e.g. 10,400 mAh = 10.4 Ah). In theory 10,400 mAh, with the Rockpi running internally at 5 volts, equates to 52 “watt-hours”. They say the Rockpi will draw up to 18 watts, not including power draw from, say, a CPU fan, or peripherals like mouse/keyboard or a touchscreen without its own separate power supply, etc. Unless you’re going to be rendering 4k videos while also copying ~100 gigs of data back and forth between your SD card and eMMC module, I kind of doubt you will be pulling 18 watts with any regularity. You can find more detailed info on power draw elsewhere in the forum, as well as tips on conserving power I am sure.
NOW after all that, I’ll offer a suggestion of a power brick that I bought ~2 years ago that I’ve been really really impressed with. It holds a charge really well, it was super affordable, it had great reviews back when I bought it and it appears to still have excellent feedback on Amazon - never heard of the company “charmast”, seems like they are Japanese? Here’s a link to the latest version of the unit that I purchased ~2 years ago.\
