Key Difference: AA and AAA batteries are two of the most commonly used batteries. They primarily differ in their physical dimensions. AA battery is longer than AAA battery. Both the batteries also vary in many other aspects like power, usage, cost, etc.

Batteries are widely used in our day to day lives. One can easily find appliances that run on batteries like remote control, toys, clocks, etc. in homes and offices. Batteries can be classified into many categories. Among the various batteries, AA and AAA are the most common types. These batteries primarily differ in their sizes. However, they both generally supply the equivalent amount of charge, i.e. 1.5 volts.

AA or Double A battery refers to a standard battery with physical dimensions –

• Body – cylindrical
• Measurement - 50 mm in height with a diameter of 14.5 mm. This battery is also known as R6.

Many batteries have been developed based on this standard. These batteries can further be categorized according to various specifications like performance, suitability, etc. The size of the battery also determines the amount of current that will be provided by the battery.

AAA or triple A battery refers to a standard battery with physical dimensions –

• Body – cylindrical
• Measurement – 44.5 mm in height with a diameter of 10.5 mm. It is also known as R03.

Thus, one of the most apparent differences between the two batteries is the size. AAA batteries are smaller than AA batteries. Due to the size, AAA batteries also carry a smaller amount of material/charge as compared to the AA battery.

Comparison between AA and AAA battery:

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