Type: Alkaline
Voltage: 1.5 V
Diameter: 15.6 mm
Height: 5.95 mm
Best Use By: 2008
Product is Brand New Sealed
Also known as: PX625 / PX13 / EPX625 / V625PX / MR09 / MR9 / H-D / HD
/ RPX625 / RM625 / KX625 / HD1560 / 1124MP / Mallory RM-625R / Eveready E625N /
Burgess HG-625R / 4370 / 4371 / V13PX / EPX13 / V625PX / HD625 / PN625 / RM625 /
4625 / 625 / H1560 / HD-D / M01 / M20 / 8930
The MR9, PX13 and PX625 is is a discontinued Mercuric Oxide coin type cell that
was commonly used in cameras and is now banned because of toxicity and
environmental fears.
The original PX625 mercury cell produced 1.35V.
There are three possible mercury free replacements for this PX625, PX13 or MR9
cell:
* genuine Mercury cell, the PX625, PX13 or MR9 - but they are rare and hard to
find.
* the equivalent alkaline cell, the LR9 or V625U.
* the equivalent silver oxide cell, the S625PX.
* the equivalent zinc air cell, the WeinCELL MRB625.
* a voltage reducing adapter, the MR-9 adapter and a silver oxide 386 cell
The least expensive PX625 replacement is the alkaline cell, the LR9 or V625U.
They fit perfectly but, as with all alkaline cells the voltage is not stable, it
drifts down from 1.5V towards 1.35V (the voltage of the original Mercury cell)
and then lower still. If you use the cell in a camera that needs a steady
reference voltage, as the voltage is not steady throughout the useful life of
the cells, you need to constantly adjust how you compensate.
Because the S625PX silver oxide cell produces a steady 1.55V, you are able to
compensate for the higher voltage by a fixed number of stops or by adjusting the
ASA setting. There may be as many as two f-stops underexposure by a camera that
uses 1.55v instead of the original 1.35v, but the compensation you require is
constant.
Another PX625 replacement is a zinc air battery. The WeinCELL MRB625 is a custom
zinc/air battery designed to replace banned mercury batteries. WeinCELLs deliver
the same 1.35 V voltage and stability of output as did the mercury PX625
batteries so there is no need to adjust your exposure. The WeinCELL MRB625
batteries last much longer than hearing aid batteries, some times up to a year.
To achieve this longer life, the MRB625 used a proprietary electrolyte and has
only two small air holes, instead of the 7 larger holes found in standard
hearing aid batteries.
Possibly the 'Rolls Royce' of replacements is the MR-9 adapter fitted with a
silver oxide 386 cell. The MR-9 adapter is the shape and size of a PX625 cell,
has a recess into which a 1.55V silver oxide 386 cell can be dropped and and
contains voltage regulating electronics to drop the voltage to match the 1.35V
of the original mercury cell. The MR-9 adapter is expensive, but it can be
reused time and time again with inexpensive silver oxide 386 cells. Over time
you may find the MR-9 adapter will actually save you money over the other
options.
