A car battery can freeze at different temperatures depending on its state of charge. Here’s a general guideline:
| State of Charge | Freezing Temperature |
|---|---|
| Fully Charged (12.6V or higher) | -76°F (-60°C) |
| 50% Charged (12.2V) | -10°F (-23°C) |
| Discharged (11.8V or lower) | 32°F (0°C) – Freezes like water |
Why Does a Car Battery Freeze?
- A fully charged battery has a lower freezing point because the electrolyte is mostly sulfuric acid.
- A discharged battery has more water, making it freeze at a higher temperature.
- Freezing can cause battery casing to crack and damage internal components.
How to Prevent Battery Freezing:
✅ Keep the battery fully charged (use a trickle charger in cold climates).
✅ Park in a garage or insulated space.
✅ Check and replace old batteries before winter.