How to Find the Right Button Cell Battery
Button and coin cell batteries are small but essential. Watches, calculators, car keys and many electronic devices can run for years from a single cell. The number of battery codes can be confusing: CR2032, LR44, CR2016 and SR626SW are all different. So which one do you need?
How to Read a Button Cell Code
- First letter: chemistry. C means lithium, L means alkaline and S means silver oxide.
- Second letter: shape. R means round.
- Numbers: approximate dimensions. For example, CR2032 is about 20 mm in diameter and 3.2 mm thick.
Button Cell Cross-Reference: Device to Battery Type
| Device or application | Common type | Voltage | Chemistry |
|---|---|---|---|
| Slim wristwatches | SR626SW / SR621SW | 1.55 V | Silver oxide |
| Medium-sized wristwatches | SR1130SW / SR1116SW | 1.55 V | Silver oxide |
| Calculators | LR44 / AG13 | 1.5 V | Alkaline |
| Modern car keys | CR2032 | 3 V | Lithium |
| Older car keys | CR2016 / CR1620 | 3 V | Lithium |
| Computer motherboards | CR2032 | 3 V | Lithium |
| Thermometers | LR41 / AG3 | 1.5 V | Alkaline |
| Hearing aids | PR44 / PR41 / PR536 | 1.4 V | Zinc-air |
| Light-up toys and small LEDs | AG10 / LR1130 | 1.5 V | Alkaline |
| Security keys and tokens | CR2032 | 3 V | Lithium |
Alkaline vs Silver Oxide vs Lithium
| Chemistry | Advantages | Typical uses |
|---|---|---|
| Alkaline (LR) | Affordable and widely available | Calculators and simple toys |
| Silver oxide (SR) | Stable voltage and long service life | Precision watches and measuring devices |
| Lithium (CR) | Long shelf life and strong temperature performance | Car keys, motherboards and outdoor electronics |
How to Find the Correct Button Cell in Three Steps
- Open the device: Read the type printed on the old battery.
- Check the dimensions: If the label is unreadable, measure the diameter and thickness carefully.
- Follow the manufacturer's specification: Use the device manual as the final reference, especially for watches and medical equipment.
Conclusion
The code printed on the old battery is usually the safest way to identify a replacement. Common everyday button cells include CR2032 for car keys and electronics, LR44 / AG13 for calculators and SR626SW for watches. Always match the type, voltage and size before replacing a cell.
