Electrolyte Freezing

The freezing point of electrolyte depends on a specific gravity. Since freezing may ruin a battery, it should be protected against freezing by keeping it in a charged state.

As long as the green dot is visible in the hydrometer, the freezing point of the battery will be somewhere below -32°C (-25°F).

The higher the state of charge, the lower the freezing point. A fully charged battery will not freeze until the temperature gets below -65°C (-85°F).