CR vs BR batteries
Both are 3 V lithium coin cells in shared sizes. CR (lithium manganese dioxide) has more capacity and better pulse current; BR (lithium carbon monofluoride) tolerates heat and long storage.
Both are 3 volt lithium coin cells and both come in the same sizes, so a BR2032 and a CR2032 are the same shape. The difference is the chemistry inside. CR is the standard type: more capacity and better at delivering short bursts of current, which is what a car key or a sensor needs. BR handles much higher temperatures and loses less charge over many years, which is why it turns up in industrial and automotive electronics. For consumer devices, CR is nearly always the right answer.
- Verdict:
- CR for everyday use, BR for heat and long-term stability
Side by side
| Specification | CR | BR |
|---|---|---|
| Chemistry | Lithium manganese dioxide | Lithium carbon monofluoride |
| Nominal voltage | 3 V | 3 V |
| Capacity | Higher | Lower |
| Pulse current | Better | Limited |
| Temperature range | About −20 to 70 °C | About −30 to 125 °C |
| Self-discharge | Low | Very low |
| Typical use | Key fobs, motherboards, sensors | Automotive, industrial, high heat |
Substituting one for the other
A BR will physically fit any CR slot of the same number and the voltage matches, but it cannot supply the same short bursts of current. In a key fob that transmits in pulses, a BR can read as flat while still holding charge. Going the other way, a CR in a hot engine bay will not last.
Why BR exists
Carbon monofluoride is stable at temperatures that would degrade a CR cell, and loses very little charge per year. For a component sealed inside a car for a decade, that matters more than capacity.
What you will actually find
Shops stock CR almost exclusively. If a device specifies BR it is usually industrial, and the specification is deliberate rather than incidental.
Check before you swap. Batteries with similar dimensions are not always interchangeable. Always verify voltage, chemistry and the requirements printed in your device manual before fitting a replacement.