Voltage. AA and AAA are 1.5 volts. A 9volt has essentially 6 AAAA batteries in them ran together in series to provide 9-volts. It’s a common standard, and has the snap terminals which is good for things that are moving around instead of a spring loaded compartment.
Voltage. AA and AAA are 1.5 volts. A 9volt has essentially 6 AAAA batteries in them ran together in series to provide 9-volts. It’s a common standard, and has the snap terminals which is good for things that are moving around instead of a spring loaded compartment.
https://upload.wikimedia.org/wikipedia/commons/e/ea/9V_innards_3_different_cells.jpg
Cool picture showing the various cells making up the typical 9v battery.