Why Winter Affects Car Batteries Car batteries work by producing a chemical reaction that generates electrical power. Cold weather slows down this reaction, reducing the battery’s ability to deliver the necessary current to start the engine. At 0°F (-18°C), a battery can lose up to 60% of its strength compared to warmer conditions. This means a battery that worked fine in fall might struggle in winter. Additionally, winter demands more from your battery. Using heaters, defros
