Index / BR1225

BR1225

BR1225 — lithium, 3 V, 12.5 x 2.5 mm. Current, and the only other cells this size are ones Energizer no longer lists: CR1225.

Warning — button cell

BR1225 is a button cell: 12.5 mm across and 2.5 mm tall. United States law defines that class by the shape alone — a single cell battery with a diameter greater than its height, 16 CFR 1263.2 — and not by what is inside it. Swallowed, a cell this shape can lodge instead of passing, and it is the current, not the metal, that does the damage. If one has been swallowed, or put in a nose or an ear, call the United States national Poison Help line at 1-800-222-1222 straight away and do not wait for symptoms.

At 12.5 mm and 3 V it is under the 16 mm diameter that lodges most readily — which makes it easier to swallow, not safer. The same current runs for as long as it sits.
Reese's Law (15 U.S.C. 2056e) and 16 CFR part 1263 put child-resistant packaging and a warning label on this class; packages manufactured or imported after 21 September 2024 carry it. That is why the pack is hard to open.
The same rule says what to do with the used cell, in its own words: dispose of it at once, keep it away from children, and do NOT put it in household trash (16 CFR 1263.4(b)(3)). Tape over both faces first — a cell too flat to run a watch still has enough left to burn.

What fits the compartment, and what does not

Fit answers whether it enters the compartment. Voltage answers whether the circuit will notice. A cell that fits is not always a safe substitute.

Cell	Fit	Voltage	Chemistry	Capacity
CR1216	sits lower	3 V 0%same volts	lithium	—
CR1220	sits lower	3 V 0%same volts	lithium	—

Nothing Energizer still lists is the same depth. The 2 options below share the diameter and run 1.6 to 2 mm against this cell's 2.5, and every one of them is shallower, so each stands off the contact by the difference — a spring may take that up and a flat tab will not.

Nominal3V

Diameter12.5mm

Height2.5mm

In the Energizer catalogListed

What the designation encodes, and what it rounds off

The number in the name is rounded. BR1225 encodes a diameter of 12 mm, but the cell measures 12.5 mm: the standard writes whole millimeters and drops the remainder. The height, 2.5 mm, is carried exactly. 1 other designation shares the shell: CR1225.

What this cell can stand in for

1 designation Energizer no longer lists points at this cell as the closest thing it does list, and the voltage is the same. If a device was built for one of them, this is a straight substitution.

Every column of a row describes the discontinued cell it names. Fit reads that way too: it says whether that cell would enter this compartment, not whether this one enters its. Voltage is measured against this cell, the same way everywhere on the page: each row shows the discontinued cell’s own voltage and how far that voltage sits from this one.

Discontinued cell	Fit	Voltage	Chemistry
CR1225	drop-in	3 V 0%same volts	lithium

From BatteryCrossEvery designation in one pageEach code with what it measures and what it replaces

What a lithium coin is asked to hold

A lithium coin 12.5 mm across holds 3 V with almost no self-discharge, which is why sockets that must remember something for years are cut for this shape. Same diameter, other depths: CR1216 and CR1220. They are one voltage, 3 V; depth is the only thing that changes.

2 cells measure close enough to compare against it in the Energizer data this site reads, and 2 of them are still listed. The nearest is CR1216: it enters and sits lower and runs 3 V, same volts. Energizer files it for Asia Pacific, Europe, Latin America and North America, which is where the part is sold rather than where the cell will work. The maker still lists it, under 1 product line: BR1225.

Drawn to scale

BR1225, side elevation, from the published figures

The same scale for all of them. The dashed line marks the height of BR1225: a silhouette that stops short of it will not reach the contact, one that crosses it will not let the cover close.

This cellAnother cell, same scale

Every published figure

Capacity is missing here, and with it every figure derived from capacity: 9 figures are published, 4 fields are not.

Designation	BR1225
Chemistry	Lithium Photo/Coin
Nominal voltage	3 V
Diameter	12.5 mm
Height	2.5 mm
Weight	0.8 g
Volume	0.3 cc
In the Energizer catalog	Listed
Listed for	Asia Pacific, Europe, Latin America, North America

What the datasheet does not say

Beyond size and voltage the sheet for BR1225 is thin: 3 published figures below, and no impedance, no cutoff and no operating range at all. That silence is the maker's, not ours.

The part occupies 0.3 cubic centimeters and weighs 0.8 g. Energizer files it for Asia Pacific, Europe and Latin America.

The code read as a measurement: BR1225 encodes 12 x 2.5 mm where the sheet measures 12.5 x 2.5 mm. The standard writes whole millimeters, so that is rounding and not disagreement.
Mass against volume: 0.8 g filling 0.3 cubic centimeters. When the printing has worn off, a kitchen scale separates two cells of one envelope faster than a caliper does.
Where the part is filed: Asia Pacific, Europe, Latin America and North America. That is a statement about the maker's distribution and not about where the cell works.

Is that a lot of energy?

Capacity is not published for this cell, so it is absent from the energy ranking rather than placed at the bottom of it. What can be compared is size: 12.5 x 2.5 mm, against a shell that holds 2 designations.

A width the catalog keeps returning to

12.5 mm is a width this catalog keeps coming back to: 3 coins sit within half a millimeter of it, BR1225 included.

SR48 — the next step down by volume: 0.26 cubic centimeters against this cell's 0.3.
CR1616 — the next step up: 0.32 cubic centimeters, 107% of this one.
CR1216 — 12.5 x 1.6 mm, 3 V, lithium.
CR1220 — 12.5 x 2 mm, 3 V, lithium.
2 of those ones are still listed. 16 of the 82 coins share its 3 V exactly.

Nothing else is stamped on this one

Nothing else is printed on BR1225 in the Energizer data this site reads: one designation, no trade marking, no part number. CR1225 in the same envelope is named otherwise, so a marking you are holding is more likely theirs.

The cell that differs only in depth

The code says the size, so the cells that get confused with BR1225 are the ones that keep its diameter and change its depth. 2 cells share this diameter at depths from 1.6 to 2 mm, and every one of them enters the same opening.

CR1216 — same diameter, 1.6 mm tall against this cell's 2.5: 0.9 mm shallower, which the standard writes into both codes.
CR1220 — same diameter, 2 mm tall against this cell's 2.5: 0.5 mm shallower, which the standard writes into both codes.
1177SO — 11.6 mm across at 1.55 V against 12.5 mm here, 0.9 mm apart: loose in this holder.
201 — 11.6 mm across at 1.5 V against 12.5 mm here, 0.9 mm apart: loose in this holder.
On a scale the difference shows before it shows on a caliper: this one weighs 0.8 g.

A thin record, and what that costs

The maker's record for BR1225 is thin: 4 of 7 fields are blank, and only 3 are filled. What follows from a blank is an absence on this page, never a guess.

The blanks are the same in all 1 record behind this designation, so they are the catalog's silence and not a merge losing a value. What is not missing is the envelope: 12.5 x 2.5 mm, published and checked against the designation itself.

No capacity — so this page cannot tell you how long it runs, and every energy figure that depends on it.
No cutoff voltage — so this page cannot tell you what the capacity figure was counted down to, without which the capacity is a number without a scale.
No impedance — so this page cannot tell you whether the cell can drive a pulse, which is the whole question in a watch or a sensor.
No operating temperature — so this page cannot tell you whether the maker claims anything at all below freezing.

Before you swap anything

Everything here is computed from published dimensions and nominal voltages. That answers whether a cell enters the compartment and whether the voltage matches on paper. It does not answer what your device does with the difference, and it cannot: a cell that fits can still be the wrong cell.

One more limit, and it is the biggest. This site reads a single manufacturer’s catalog. When a page says a designation is not listed, that means Energizer no longer offers a part under it — not that nobody makes the cell. Other makers may still sell it, and for common sizes they usually do.

A voltage difference is one relation between two cells, and this page prints it from the cell it is about — in every table on the page, including the one listing cells no longer made. A figure always belongs to the cell whose voltage is printed beside it: a cell that runs lower than this one carries a minus here, one that runs higher carries a plus, and two cells at the same nominal voltage carry zero. Meet the same pair on the other cell’s page and the sign is the other one, with the figure taken against that cell instead of this one; where the two run at the same voltage, both pages print zero. The class beside the figure is not read off that figure directly. It is decided on the gap itself, taken against the higher of the two nominal voltages, so one pair of cells gets one class whichever page you meet it on: counted from this side the boundary of the class that still runs falls at 20.0% below and 25.0% above, which is the same gap divided once by the larger nominal and once by the smaller. What genuinely differs between the two directions is the consequence, and the words carry it: a cell that runs low makes a calibrated instrument read below true, and a cell that runs high makes it read above.

3 things this site cannot see. Whether the contacts reach a shorter cell. Whether the device was calibrated for a chemistry that holds its voltage flat, which silver oxide does and alkaline does not. Whether the equipment tolerates the higher current a different chemistry can deliver. Rechargeable cells are never a drop-in for primary cells regardless of size.

Cells measured next to this one

1 cell sits at exactly this size, and 2 more share the diameter at other depths. The first group is interchangeable by measurement; the second is not.

CR1225 — 12.5 x 2.5 mm, 3 V
CR1216 — 12.5 x 1.6 mm, 3 V
CR1220 — 12.5 x 2 mm, 3 V

Where these numbers come from

Dimensions, voltages, chemistries and capacities are published by the manufacturer and reproduced without change. Everything else on the page is ours, computed from those figures: whether one cell fits where another sat, how far apart their voltages are, stored energy and energy per cubic centimeter, the rank within a shell, and the check of the designation against the measured size.

Fit is decided within 0.3 mm on every axis, which is the order of a contact spring's travel. Voltage classes are decided by consequence, not by roundness, and they are decided on the gap between two nominal voltages taken against the higher of the two: 2.0% or less of it is the same working voltage, 6.0% starts to matter to a calibrated instrument, and past 20.0% it is a different class altogether. Measuring the gap against the higher figure is what makes the verdict the same from either cell’s page, while the printed percentage stays counted from the cell you are reading about. Cells with identical stored energy share a rank instead of being ordered arbitrarily.

Ranking uses capacity times nominal voltage, because capacity alone is not comparable across chemistries: 150 mAh at 3 V is twice the energy of 150 mAh at 1.5 V. Neighbors are chosen by measurement and never alphabetically, because two cells filed next to each other by name usually have nothing in common. A blank in any table means the maker publishes no figure, which is not the same as zero.

Source: Energizer technical data, retrieved 1 September 2026.

The record behind this page

Every figure on this page comes from one catalog record, number 207, and it is linked below. The sheet is the document the dimensions, voltage and capacity were read out of.

[1] Energizer catalog record 207, active in the snapshot. Technical data sheet: BR1225GL0626.pdf.

Every figure above is reproduced from those records without change; the comparisons are ours and are described on the method page. Snapshot: Energizer technical data, retrieved 1 September 2026.

Putting this on a forum or a repair page? The same answer without the site around it — fit, voltage, chemistry and the limits that go with them — is at /embed/br1225/. It loads nothing from anywhere else. Paste this:

<iframe src="https://batterycross.com/embed/br1225/" width="100%" height="520" loading="lazy" title="BR1225 replacements"></iframe>