At One Place

LR9 battery

What replaces a LR9
PX625A, V625U, 625A, EPX625G, D625, MR09
1.5 V alkaline, 15.6 × 6.2 mm (diameter × height)

The LR9 is a single-use 1.5 V alkaline button cell. The codes below are the same physical cell sold under different manufacturer names, and any of them will fit.

Specification

IEC designation
LR9
Nominal voltage
1.5 V
Chemistry
Alkaline
Size
15.6 × 6.2 mm (diameter × height)
Typical capacity
190 mAh
Rechargeable
No — never charge it

Codes that mean the same battery

Different manufacturers, one physical battery. Voltage, chemistry and dimensions all match.
Code Fits?
PX625A Yes — same cell
V625U Yes — same cell
625A Yes — same cell
EPX625G Yes — same cell
D625 Yes — same cell
MR09 Yes — same cell
KA625 Yes — same cell
A625PX Yes — same cell
LR09 Yes — same cell

Codes that look close but are not

Code Why it is not a substitute
PX625 mercury The cell this replaces mechanically but not electrically. The original was 1.35 V and flat; this is 1.5 V falling steadily. In a torch or a calculator that is irrelevant. In a light meter it means every reading is wrong, by an amount that changes as the battery ages.

The LR9 is a primary cell and must never be put in a charger. Charging a sealed primary battery builds gas pressure inside a can with no vent designed for it, which is how they rupture or catch fire. Rechargeable look-alikes exist for several sizes and carry different codes — check the code, not the shape.

Where it turns up

  • Vintage camera meters where absolute accuracy is not needed
  • Older calculators
  • Car key torch bulbs
  • Small instruments built for the PX625 shell

Capacity varies between roughly 170 and 200 mAh by brand. Sold as a PX625 replacement, which it is dimensionally and is not electrically — see the PX625 entry for what to use instead in a meter.

Common questions

What is equivalent to a LR9?
PX625A, V625U, 625A, EPX625G, D625, MR09, KA625, A625PX, LR09 — all the same 1.5 V cell under different manufacturer codes.
Can I use a PX625 mercury instead of a LR9?
The cell this replaces mechanically but not electrically. The original was 1.35 V and flat; this is 1.5 V falling steadily. In a torch or a calculator that is irrelevant. In a light meter it means every reading is wrong, by an amount that changes as the battery ages.
Is the LR9 rechargeable?
No. It is a primary cell — charging one risks rupture or fire. Rechargeable look-alikes exist in the same size under different codes.

Related pages

Sources

  1. Typical range compiled from manufacturer specifications — At One Place

How these figures are compiled and checked