What does the “AA” on a battery stand for?

The height and breadth of a battery are indicated by the lettering on the battery. “50.5mm x 14.5mm” is what AA denotes. The battery grows in size in direct proportion to the letter’s date of issuance. D is significantly larger than C, etc. In terms of size, “A” dwarfs both “AA” and “AAA”.

Single-cell dry batteries in the shape of an AA (or double-A) are the most common type. The size is referred to as R6 by the IEC 60086 standard and as 15 by ANSI C18. JIS of Japan has given it the designation UM-3. According to official British documentation, it is referred to as either D14 (normal cell) or HP7 (zinc chloride “high power” variant).

Portable electrical equipment frequently uses AA batteries. Rechargeable or disposable, the single electrochemical cell of an AA battery serves as the power source for the device it’s housed in. Assorted chemistry goes into their creation. However, unless explicitly stated by the manufacturer, equipment made for AA batteries typically only accepts 1.2-1.5 V, unless otherwise stated.

The AA battery size was established in 1947 by the American National Standards Institute (ANSI), but it had been used in torches and other electrical novelty items before formal standardization was achieved in 1907 when it was introduced by the American Ever Ready Company. Batteries of this size can have a variety of ANSI and IEC nomenclature designations based on the cell’s characteristics and chemistry. Penlight batteries are commonly referred to as such because of their widespread use in tiny flashlights.

Dimensions

The diameter of an AA cell is 13.5–14.5 mm (0.53–0.57 in) and the length is 49.2–50.5 mm (1.94–1.99 in). For the positive terminal button, the diameter should be at least 1 mm while the diameter of the flat negative terminal should be at least 7 mm. 14500 Lithium Batteries with a 53 mm protective circuit have a longer lifespan.

Lithium AA batteries weigh 15 g (0.53 oz), whereas rechargeable Ni-MH batteries weigh 31 g. Alkaline AA batteries weigh about 23 g (0.81 oz) (1.1 oz).

Chemistry and the ability to perform

Cells from the earliest stages of development

Dry cell AA batteries have a capacity of 400–900 milliampere hours, depending on the test circumstances, duty cycle, and cut-off voltage of the battery. Batteries made of zinc and carbon are commonly referred to as “all-purpose” batteries. “Heavy Duty” and “Super Heavy Duty” are commonly used labels for zinc-chloride batteries that have a capacity of between 1000 and 1500 mAh. Higher-capacity alkaline batteries (from 1700 mAh to 2850 mAh) cost more than zinc-chloride batteries, but they maintain their charge longer. Alkaline AA batteries are referred to as LR06 and AM-3 by the IEC and JIS, respectively.

These batteries are used in devices that consume a lot of currents, such as digital cameras, where their high cost is mitigated by longer battery life and a more stable voltage during discharge. In comparison to alkaline batteries, the capacity of a Li-FeS2 battery does not suffer nearly as much from high discharge currents as it does in alkaline batteries. When compared to alkaline cells, lithium disulfide batteries are less prone to leak. The caustic electrolyte from a leaking alkaline battery poses a particular danger to expensive electronic equipment since it can come into touch with the device’s delicate circuitry. Alkaline zinc batteries are not compatible with lithium iron disulfide batteries. lithium iron disulfide (LiFeS2) can have an open-circuit voltage of up to 1.85V while maintaining an acceptable closed-circuit voltage for use in zinc-based batteries. Lithium iron-disulfide batteries with an open-circuit voltage of 1.70 volts are completely depleted, but a new alkaline zinc battery can have an open-circuit voltage of 1.6 volts

Cells that may be charged

Nickel-cadmium (NiCd) rechargeable batteries have a capacity of around 600–1,000 mAh, whereas nickel-metal hydride (NiMH) rechargeable batteries have capacities ranging from 600–2,750 mAh. If you’re looking for 14500 Li-ion batteries, you’re better off calling them 14500 Li-ion batteries, rather than just AA.

Although NiMH and Lithium-Ion AA/14500 batteries can only give a portion of their low current capacity before reaching 1 C, alkaline and zinc-chloride (“Heavy Duty”/”Super Heavy Duty”) batteries cannot.

An inbuilt buck converter at the positive electrode of the 14500 Li-ion batteries, supplied by the Chinese business Kentli as “Kentli PH5” since 2014, is used to the downstep output voltage from the regular 3.7 V to a fairly stable 1.5 V AA standard voltage. It charges the AA battery by exposing the standard 3.7 V Li-ion electrode in a ring around it. Because of its lithium-ion chemistry and reduced self-discharge rate of 3 percent per month, it is more compatible with alkaline AA devices due to its regular voltage. The poor efficiency of the step-down converter results in a meager battery capacity of 1600 mAh (1.5 V) at 50 mA discharge.

Nickel-zinc cell (NiZn) AAs are also available, however, they are not frequently utilized.