Is it better to charge the car to 90% or 100%?

Charging an electric vehicle to 90% and 100% each has its pros and cons, so let's take a look together!

1. Advantages of charging to 90%

1. Extends battery life

Lithium-ion batteries have more active internal chemical reactions when fully charged, which accelerates the aging of electrode materials and capacity degradation. Charging to 90% can reduce the time the battery spends in a high voltage state, thereby slowing down the aging process and extending the battery's lifespan.

For example, some electric vehicle manufacturers recommend users set the charging limit to 90% for daily use to protect the battery. Consistently following this charging strategy can help the battery maintain a high capacity and performance even after multiple charge and discharge cycles.

2. Improves charging efficiency

During the charging process, especially as it approaches full charge, the charging speed gradually slows down. This is because the battery management system reduces the charging current to prevent overcharging. Therefore, charging to 90% usually takes less time than charging to 100%, which can improve charging efficiency and save time.

For users who need to quickly recharge, charging to 90% can provide enough power in a shorter time to meet daily travel needs.

2. Advantages of charging to 100%

1. Meets long-distance travel needs

If there are plans for long-distance travel, charging the battery to 100% can provide the maximum range, reducing the number of charging stops and increasing travel convenience. Especially in areas with fewer charging stations, a full charge can offer more driving range and reduce anxiety about running out of power.

For example, during a long road trip, users may choose to fully charge the battery to ensure a smooth journey.

2. Fully utilizes battery capacity

For users with high range requirements, fully charging the battery can maximize its capacity and provide the longest driving distance. This is particularly important in special situations, such as emergency rescues or long-distance transport, where vehicles need as much power as possible.

Additionally, some electric vehicle battery management systems adjust based on the actual capacity of the battery, and a full charge allows the system to more accurately assess the battery's status, optimizing vehicle performance and range.

3. Comprehensive considerations

1. Choose based on actual needs

If daily travel distances are short and charging is convenient, consider setting the charging limit to 90% to extend battery life. If there are long-distance travel needs or high range requirements, charge the battery to 100% before departure.

For example, for daily commuting, charging to 90% is sufficient; while preparing for a long trip, charge the battery fully in advance.

2. Consider charging frequency

If quick recharges are often needed, consider charging to 90% to improve efficiency. If charging frequency is low, fully charging to 100% when there is ample time can fully utilize battery capacity.

For example, for users who use public charging stations, if charging time is limited, they can choose to quickly charge to 90%; while users with private charging stations can fully charge the battery at night or during other free times.

3. Pay attention to battery health

Regardless of whether you choose to charge to 90% or 100%, you should pay attention to the health of the battery. Regularly check parameters such as battery capacity and internal resistance, and if there are any abnormalities, perform maintenance or replacement promptly. Also, follow the charging recommendations and maintenance manuals provided by the vehicle manufacturer to ensure battery safety and performance.

For example, you can use the vehicle's battery management system or third-party software to monitor the battery's health and adjust charging strategies based on actual conditions.

In summary, charging an electric vehicle to 90% and 100% each has its advantages and disadvantages. Users should consider factors such as actual needs, charging frequency, and battery health to choose a charging strategy that suits them.