I've had plenty of portable power banks in my time, and it's been a bit of a guilty pleasure of mine to upgrade them every few years. Generally speaking, that's involved the batteries getting smaller, as the tech behind their casings has slowly but surely shrunk over time.
For a couple of years, my default pick when packing a backpack for a working day or a short trip was an Anker 10,000 mAh battery that had a built-in retractable USB-C cable, and it worked a treat right up until I lost it a couple of months ago (I wish I knew where).
