Size 13 hearing aid battery

Standard BTE hearing aid battery. Orange tab, 7.9 mm diameter, 5.4 mm height, ~310 mAh capacity. Nearly double the runtime of Size 312. IEC code: PR48.

Specifications

Property	Value
IEC designation	PR48
Tab color	Orange
Chemistry	Zinc-air
Nominal voltage	1.45 V
Diameter	7.9 mm
Height	5.4 mm
Typical capacity	~310 mAh
Typical runtime	6–14 days
Shelf life (with tab)	3–4 years

Compatible devices

Behind-the-ear (BTE) hearing aids — the traditional larger style
Full-shell in-the-ear (ITE) aids
Half-shell ITE aids
Some cochlear implant sound processors

How to identify it

Look for the orange tab. The Size 13 shares the same 7.9 mm diameter as the Size 312 — the key difference is height: 13 is 5.4 mm tall vs 3.6 mm for 312. It is visibly thicker when the two are placed side by side.

Activation

Remove the orange tab completely and wait 60–120 seconds before inserting. The larger zinc-air electrode benefits from the full rest period; users frequently report improved volume and consistency compared to immediate insertion.

Common mistakes

Inserting a Size 312 in a Size 13 slot — the battery will rattle and make poor contact. The door may still close because the diameters match, but it will not work reliably.
Inserting a Size 13 in a Size 312 slot — the door will not close. The battery is too thick.

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