AAAA
Cylindrical Cells · 5 specs
Direct Answer
A AAAA battery (IEC designation LR8D425) is a 1.5V Alkaline cell measuring approximately 8.3mm in diameter and 42.5mm in length -- smaller than a AAA. It's used in devices with especially tight internal space, such as laser pointers, some styluses, and compact LED penlights.
Source: IEC 60086-2 / Energizer E96 datasheet · Last reviewed Aug 28, 2026
Specs
| Diameter | 8.30 mm |
| Overall Length | 42.50 mm |
| Nominal Operating Voltage | 1.50 V |
| Chemistry | Alkaline |
| Nominal Capacity (at 10mA) | ~625 mAh |
Smaller Than a AAA
The AAAA is the smallest of the common alkaline cylindrical cell sizes, noticeably narrower and shorter than a AAA, and correspondingly lower in capacity -- manufacturer discharge data shows roughly 625-680mAh at a light, continuous 10mA draw, tapering to well under 300mAh at higher drain rates around 200-300mA. That drop-off is steeper than in larger alkaline formats, reflecting how little internal volume the cell has to work with.
Its small size limits it to devices with very light, intermittent power needs: laser pointers, some styluses and pen-style lights, and small precision electronics where a AAA still wouldn't fit.