AAAA battery


The AAAA battery is 42.5 mm long and 8.3 mm in diameter. The alkaline cell weighs around 6.5 g and produces 1.5 V. This size battery is also classified as R8D425 and 25. The alkaline battery in this size is also known by Duracell type number MN2500 or MX2500 and Energizer type number E96.
Historically its consumer electronics use was very limited, and only since the 2010s has it made its appearance in the stores where one would buy its more common AAA relative.
Zinc–carbonAlkalineNiCdNiMHLi-Ion
IEC nameR8D425LR8D425KR8D425HR8D425
ANSI/NEDA name25D25A
Typical capacity300 mAh500–600 mAh 325–500 mAh160–170 mAh
Nominal voltage1.50 V1.50 V1.25 V1.25 V3.7 V

Uses

This battery size is most often used in small devices such as laser pointers, LED penlights, powered computer styluses, glucose meters, and small headphone amplifiers. These batteries are not as popular as AAA or AA type batteries, and consequently are not as commonly available.
Some models of alkaline nine-volt battery contain six LR61 cells connected by welded tabs. These cells are similar to AAAA cells and can be used in their place in some devices, even though they are shorter.