yes, 24Ah before losses on conversion. its the reason why i always measure battery capacity in Wh, as its the same, regardless if you're down converting to 5v, or inverting to 240V
Generally, a switching convertor has an efficiency of 80-90%, 0.8 x 24 = 19.2Ah
A few notes:
- This is the battery capacity, not the actual usable capacity.
Depending on the type of battery(Starter, AGM, LFP), you can only use 50-80% of the rated capacity without sacrificing the life.
- These calculations are based on a switching power supply. A lineair power supply only lowers the voltage and will convert the remaining into heat.
In those cases, the 10Ah will remain 10Ah at 5V. If using eg 5V / 1A, you will also generate 7V x 1A = 7W of continous heat, which requires a heatsink. For some applications, a switching powersupply might not work (but generally it works)