SpecsyModels and product details
Remember which battery each thing takes
CR2032, CR2025, LR44, SR626SW. Four batteries that look the same, cost almost nothing, and are not interchangeable.
- Car key
- CR2032
- Bathroom scale
- 4 x AAA
- Kitchen scale
- CR2032
- Smoke alarm
- 9V, yearly
- Wall clock
- 1 x AA
Button cells all look identical
A car key, a bathroom scale, a kitchen timer and a watch all take a small silver disc, and all four discs are different. The number is printed on the face of the battery in text about a millimetre tall.
By the time it dies you have thrown the packet away, and the old battery is usually already out of the device and in a drawer with three others.
This is a two pound problem that reliably costs a whole trip to the shop.
How to store this so it stays useful
- One card for the whole house, listed by device rather than by battery type
- The exact code, photographed off the old battery before it goes in the recycling box
- How many the device takes, because two is a different shopping trip than one
- Safety items separately, smoke alarms and carbon monoxide detectors, with an annual reminder
- A note of which ones are rechargeable, so you do not buy disposables for them
The ones people mix up most
| Code | Common in | Confused with |
|---|---|---|
| CR2032 | Car keys, scales, motherboards | CR2025, which is thinner |
| CR2025 | Slim remotes, some keys | CR2032, which will not close the case |
| LR44 | Toys, laser pointers | SR44, the silver oxide version |
| SR626SW | Watches | Almost every other watch cell |
Worth a yearly reminder rather than a shopping list
- Smoke alarm batteries, on a fixed date you will remember, like a clock change
- Carbon monoxide detector, which often has a sealed unit with an expiry date instead
- Thermostat batteries, since a dead one turns the heating off in January
- Door lock or keypad batteries, which fail at the least convenient moment
Questions people ask
Should this be one card or many?
One card listing devices works best for batteries, because you always start from the device that died, not from the battery type.
The print on the cell is tiny, what then?
Photograph it while it is out of the device, in good light. The photo enlarges, a used cell in a dark drawer does not.
What about rechargeable batteries?
Note the capacity in mAh as well as the size, since a low capacity cell will not run a high drain device well.