AA vs AAA Battery
AA and AAA batteries are very popular cylindrical batteries available in various chemistries, each offering different discharge characteristics.
AA and AAA batteries differ in size and hence the capacity. In certain situations, using a special battery holder, one may replace AA with AAA batteries, but at the expense of battery capacity.
AA and AAA Batteries Features and Specifications
The main difference between AA and AAA batteries is in physical dimensions.
Because of a larger volume of AA batteries, AA batteries generally feature a larger capacity and are able to provide stronger discharge currents.
Note: output voltages depend on the exact chemistry type.
Both AA and AAA batteries for historical reasons feature a nominal voltage of 1.5 volts, which is the voltage of new Zinc-Carbon batteries, practically the oldest AA and AAA battery types.
The following comparison tables list some of the most popular AA and AAA battery chemistries, with their most important features and specifications.
AA Batteries Chemistries Comparison Table
|Chemistry||Common Name||Rechargeable||Typical Capacity (mAh)||Voltage (V)
|Zinc Carbon||R6, 15D||No||600 - 1600||1.5|
|Alkaline||LR6, 15A||No (Mostly No)||1800 - 2700||1.5|
|Li-FeS2||FR6, 15LF||No||2700 - 3300||1.5 (1.8 max)|
|Li-ion||14500||Yes||600 - 2000+||3.6 - 3.7|
|NiCd||KR6, 1.2K2||Yes||600 - 1000||1.2|
|NiMH||HR6, 1.2H2||Yes||700 - 2800||1.2|
|NiOOH||-||No||2200 - 2700||1.5 (1.7 max)|
|NiZn||ZR6||Yes||1500 - 1800||1.6 - 1.65|
AAA Batteries Chemistries Comparison Table
|Chemistry||Common Name||Rechargeable||Typical Capacity (mAh)||Voltage|
|Zinc Carbon||R03, 24D||No||500-600||1.5|
|Alkaline||LR03, 24A||Mostly No||850-1200||1.5|
|Li-FeS2||FR03, 24LF||No||1100-1300||1.5 (1.8 max)|
|Li-ion||10440||Yes||350-600||3.6 - 3.7|
|NiOOH||ZR03||No||1000-1200||1.5 (1.7 max)|
|NiZn||-||Yes||500-700||1.6 - 1.65|
As one can see, when the same battery chemistries are compared, the capacities between AA and AAA batteries differ.
Zinc Carbon AA vs AAA battery: Zinc Carbon batteries are non-rechargeable batteries that feature a nominal voltage of 1.5V and nominal capacity of 500-600 mAh for AAA and 600-1600 mAh for AA batteries.
Actual capacity depends on the battery age, temperature, discharge current, and similar. Zinc Carbon batteries are cheap and reliable batteries, but have short storage life (eventually they will leak), they are unable to provide stronger currents without capacity loss and similar.
Most Zinc Carbon AA and AAA batteries are used in cheaper toys and similar applications, but even there, they are being phased out by alkaline AA and AAA batteries.
Alkaline AA vs AAA battery: Alkaline batteries are non-rechargeable batteries that feature a nominal voltage of 1.5V and nominal capacity of 850-1200 mAh for AAA and 1800-2700 mAh for AA batteries.
Alkaline AA and AAA batteries are the most common non-rechargeable AA and AAA batteries and some of the most common batteries on the market.
Li-FeS2 AA vs AAA battery: Li-FeS2 or Lithium Iron Disulfide batteries are types of non-rechargeable AAA and AA lithium batteries featuring a typical voltage of 1.5 V, excellent capacity, and very long shelf life of up to or even more than 20 years.
The Open Circuit Voltage (OCV) of Li-FeS2 batteries is 1.8V, but as soon as the batteries are being discharged, the actual voltage drops down to 1.5V.
AAA Li-FeS2 batteries feature a typical capacity of 1100-1300 mAh, while AA Li-FeS2 batteries feature a typical capacity of 2700-3300 mAh.
Both AAA and AA Li-FeS2 batteries are used in high-drain applications and in stand-by applications where batteries must reliably operate even after years of not being used.
Li-Ion AA vs AAA battery: Li-Ion AA and AAA batteries are rechargeable batteries based on several lithium-ion chemistries with the voltage ranging from 3.2 to 3.7 volts and capacities of 350-600 mAh for AAA and 600-2000+ mAh for AA batteries.
Due to their voltage of 3.2 - 3.7 volts, Li-Ion AA and AAA batteries are not backward compatible with 1.5V AA and AAA batteries.
But, since lithium-ion AA and AAA batteries offer many advantages over non-rechargeable AA and AAA batteries, some devices support the use of both 1.5V non-rechargeable Zinc-Carbon, alkaline, and other 1.5V batteries, 3V non-rechargeable lithium batteries, and 3.2-3.7V rechargeable batteries.
Such devices are mostly LED flashlights and photo cameras and similar equipment.
Note: 1.5V battery may be replaced with 3.0-3.7V battery only if explicitly allowed by the device's manufacturer! Otherwise, voltage differences can damage or even destroy the device intended ONLY for 1.5V AA and AAA batteries.
For more information about this topic feel free to check our Types of Lithium Battery Chemistries article.
Lithium 1.5V AA vs AAA battery: In order to make rechargeable lithium-ion batteries compatible with 1.5V AA and AAA battery devices, some manufacturers offer lithium-ion batteries with control electronics that convert the battery's internal 3.2-3.7V down to 1.5V.
Such batteries feature a nominal capacity of 400-600 mAh for AAA batteries and 1000-2000+ mAh for AA lithium 1.5V batteries.
In order to recharge them, such batteries either feature a USB charging plug or a micro-USB charging port/receptacle.
NiCd AA vs AAA battery: Nickel Cadmium AA and AAA batteries are some of the oldest types of rechargeable AA and AAA batteries.
NiCd batteries feature a nominal voltage of 1.2 volts and a nominal capacity of 300-500 mAh for AAA and 600-1000 mAh for AA batteries.
Although NiCd batteries are cheap, reliable, and are able to provide very strong currents, they also suffer from a strong memory effect, contain toxic metals, and support a relatively small number of charging/discharging cycles.
These are the reasons why NiCd batteries are being phased out in favor of low self-discharge Nickel Metal-Hydride (NiMH) batteries.
NiMH AA vs AAA battery: Nickel Metal-Hydride (NiMH) AAA and AA batteries are very popular types of rechargeable AAA and AA batteries, featuring nominal voltage of 1.2V and nominal capacity of 600-1300 mAh for AAA and 700-2800 mAh for AA batteries.
Modern NiMH batteries practically have no memory effect, can provide relatively strong currents, have a very low self-discharge rate, and since they don't contain mercury, lead, cadmium, and similar toxic elements, they are environment-friendly batteries - nonetheless, they must be recycled properly after they die.
Some NiMH battery types support up to 2000 or even more charging/discharging cycles, when being charged with proper battery chargers and when NOT being discharged with extra strong currents.
For more information about these batteries, feel free to check our Nickel Metal Hydride (NiMH) Battery Chemistry article.
Li-SOCl2 AA vs AAA battery: Lithium Thionyl Chloride (Li-SOCl2) AAA and AA batteries are types of non-rechargeable batteries featuring a nominal voltage of 3.5-3.6 volts, OCV (Open Circuit Voltage) of ~3.65 volts, and nominal capacity of 600-800 mAh for AAA and 2400-2700 mAh for AA batteries.
Lithium Thionyl Chloride (Li-SOCL2) AAA and AA batteries are not directly compatible with 1.5V batteries and should NOT be used in devices intended ONLY for 1.5V AA batteries.
But, devices that may use both 1.5V and 3.0-3.7V batteries may benefit from their high energy density and extra-long shelf life.
NiOOH AA vs AAA battery: Nickel Oxy-Hydroxide (NiOOH) AAA and AA batteries are actually sub-type of alkaline batteries where nickel oxyhydroxide is added to the manganese dioxide, leading to the 1.5 V typical voltage during high drain use and 1.7 V OCV voltage.
NiOOH AAA and AA batteries have a very similar capacity to standard alkaline batteries (1000-1200 mAh for AAA and 2200-2700 mAh for AA batteries), but they can be drained using larger currents without significant capacity loss and are often used in high drain devices like cameras and other photo equipment.
NiZn AA vs AAA battery: Nickel Zinc (NiZn) rechargeable AAA and AA batteries feature nominal voltage of ~1.6V and capacity of 500-700 mAh for AAA and 1500-1800 mAh for AA batteries.
NiZn batteries feature a relatively low self-discharge rate and good discharge characteristics.
Although NiZn batteries are generally backward compatible with 1.5V batteries, note that some devices intended for NiMH batteries (1.2V) may get damaged if, for example, four NiMH batteries (4.8V) are replaced with four NiZn batteries (6V).
Long Story Short: While AAA and AA batteries are not directly replaceable due to the physical differences, each of these battery sizes is available in many different chemistries, each differing in voltage, capacity, shelf-life, price, discharge characteristics, and similar.
Most devices designed around AAA and AA batteries require and operate properly with 1.5V AAA and AA batteries, however, some of them may benefit from switching to lithium 3.0-3.7V batteries, if the device support such batteries.
If not, You may choose 1.5V lithium AAA and AA batteries with built-in DC-to-DC converters which lower the voltage down to 1.5V.
If You are unsure about the exact battery chemistry that your device supports, be sure and check its Owner's Guide or manual - better safe than sorry ...