I am preparing for a roughly 4 week period being “off grid” a lot and I just got a USB tester to which voltage, amps, watts so I can find best cables, chargers.
Quite interesting, I have now tested every cable. It does tend to align with what we are usually taught. I used a large capacity battery which is able to draw about 2.2A input act as load.
A thin 6 inch cable is able to pass through full power, 2.2A. A 6 foot long Powerline+ cable was able to give 2A. A 6 foot Powerline was able to give 1.8A. So longer cables worse than shorter cables, and higher quality cables better than lower quality cables. A non-Anker 5ft cable was only able to give 1.3A.
I also tried an Anker Powerport2 vs a non-Anker charger, and the Anker “Voltageboost” seems to be true in that the voltage became a little higher on a longer cable than the non-Anker make.
If you’re off-grid for a while and have brief on-grid times then the better the cables the faster the charge you get in any given time. If you are off-grid and using a portable charger then the higher the resistance in the cable the more of the energy is lost as heat.
I know some testers use infrared heat temperature testers to find the precise source of heat, but I only bought a $15 USB tester to just test the parts.
I recommend investing in a USB tester to take the theory and opinions out of any decisions where this matters.
At home when you’re in no rush or you have a big portable charger and dont need to worry about lost energy, then don’t worry yourself.