Yes, you can use a lithium LiFePO4 battery in a car. Lithium LiFePO4 batteries offer numerous advantages over traditional lead-acid batteries, including higher energy density, longer cycle life, and enhanced safety features. However, there are important factors to consider:

Voltage Compatibility: The voltage of a LiFePO4 lithium battery is very close to the standard 12V voltage of a car battery. However, you need to ensure that the charging system in your car is compatible with LiFePO4 lithium batteries.

Battery Management Systems: To ensure optimal performance, you might need a battery management system.

Energy Density: LiFePO4 lithium batteries are not as energy-dense as other types of batteries, so they would need to be larger in order to power an electric car.

Temperature Tolerance: Lithium LiFePO4 batteries are tolerant of higher temperatures, which is an important factor to consider when using them in a car.

However, if you are looking to use a lithium battery as a cranking battery in your car, truck, RV, or boat, then it is not recommended. For motorcycles, jet skis, or ATVs, an LiFePO4 lithium battery can be a suitable choice for a starting battery.

Please note that the performance of a specific lithium LiFePO4 battery can vary based on the manufacturer and model.