LR vs SR batteries
IEC 60086 prefixes: L is alkaline, S is silver oxide, R is round. The number that follows is the size, so LR44 and SR44 differ only in chemistry.
These are not battery names but a code system. The first letter tells you the chemistry: L for alkaline, S for silver oxide. The R means round. So an LR44 and an SR44 are the same size cell — 44 is the size — in two different chemistries. The SR costs more, holds a steadier voltage and lasts longer; the LR is cheap. Once you can read that first letter you can decode any button cell on the shelf.
- Verdict:
- L is alkaline, S is silver oxide — the number after is the size
Side by side
| Specification | LR | SR |
|---|---|---|
| First letter means | Alkaline | Silver oxide |
| Nominal voltage | 1.5 V | 1.55 V |
| Discharge curve | Slopes | Nearly flat |
| Relative capacity | Lower | Around 50% higher |
| Relative cost | Low | Three to five times more |
| Same number means | Same size | Same size |
How the code is built
IEC 60086 sets the first letter to the electrochemical system and the second to the shape. L is alkaline manganese dioxide, S is silver oxide, C is lithium manganese dioxide, P is zinc air. R is round. Everything after is dimensions.
Same number, same size
LR44 and SR44 are both 11.6 × 5.4 mm, which is why a device can take either. That is the practical payoff of the system: the number is a size, so you can substitute chemistry knowingly rather than by guesswork.
Where the trade numbers fit
Retail codes like 357, AG13 and A76 sit alongside the IEC names rather than replacing them. Where a packet gives only a trade number, the IEC code is usually printed somewhere in the small print.
Check before you swap. Batteries with similar dimensions are not always interchangeable. Always verify voltage, chemistry and the requirements printed in your device manual before fitting a replacement.