Maintenance of Electric Vehicles when Parked

When an electric vehicle (EV) is parked, its battery maintains a level of charge and is managed by the car's internal systems. Understanding how this process works is crucial for maximizing the longevity and performance of your EV.

Is the Power Always On?

Contrary to the common misconception, the power in an EV is never completely off. The vehicle's computer system, which monitors the car's security and interacts with the key fob, is always running. This continuous activity consumes a minimal amount of energy, leading to a very slight loss in charge over time. However, this depletion is so negligible that it's unlikely you'll notice any significant change unless the car has been parked for an extended period.

For charging to occur, the car must remain connected to the power supply under computer control. This ensures that the battery is properly managed and maintained.

What About the 12-Volt Battery?

While the main lithium-ion battery is designed to retain its charge for several years, the car's 12-volt battery, which provides power to the car's auxiliary systems, can start to discharge over time. This is the same as with gasoline-powered cars. However, the lithium-ion battery itself, under proper conditions, can maintain its charge for many years, provided it is not fully discharged in the first place.

When an EV is parked with the power off and not plugged in, it can lose a small amount of its remaining stored energy through self-discharge. This process occurs naturally and is not due to any malfunction but is a characteristic of the battery's internal construction. Most modern EVs can last a few months in this condition without significant issues. In comparison, traditional gasoline cars can also lose battery charge over time.

Does the EV Stop Charging Once the Battery is Full?

Yes, modern EVs have sophisticated charge control circuitry that stops charging once the battery is full. The battery management system ensures that the battery maintains optimal performance and longevity. Many EVs, such as the Tesla, allow you to customize the charging behavior, setting the charging threshold to a specific percentage of 'full' to preserve battery life. This is particularly useful for maximizing the battery's useful storage capacity for regenerative braking, ensuring that the battery remains efficient and healthy.

Additionally, the presence of solenoid contactors in many EVs disconnects the main battery from the drive motor when the vehicle is parked, and only the charging circuitry remains active to recharge the battery. This design minimizes the risk of accidental discharge and ensures the battery's longevity.

Conclusion

The maintenance of an EV when parked is essential for optimal performance and longevity. Understanding the behavior of the battery and the vehicle's systems can help you make informed decisions about how to care for your EV. Regular check-ups and adherence to the manufacturer's recommendations will ensure that your EV remains in top condition, providing years of reliable service.