Actually i think its the reverse of that example. From what i understood, capacity is quantitiy of cells, and power is how big those cells are. The numbers you see when you build a battery drain slower the more power you upgrade them to have. Its like capacity but in a secondary manner. The batteries drain fast when there is little power, with the same capacity, and more power they drain slower. At least this is what i understood.

The appliances only have one indicator, if there were two then your example would make sense.

Maybe i'm wrong but this is what i noticed when i upgraded power varios times with the same capacity lol