Battery Health

Battery capacity and maximum range decrease with usage. The Battery Health feature helps you visualize and track this effect.

How does it work?

Batteries are difficult to measure due to their ever-changing chemical composition. Tessie takes many measurements over time — every time you charge 5 kWh or more — to accurately calculate the state of your battery.

Why is the usable capacity less than I expect?

Batteries have an unusable buffer (typically between 3-5 kWh) to protect the battery. For example, if you buy a Tesla with a 60 kWh battery, the usable capacity may be around 57 kWh.

Setting the original battery capacity

You can change the original capacity by pressing the number on the battery health gauge. Battery health will automatically recalculate.

Tessie calculates the original battery capacity using data from other Tesla owners with your vehicle configuration. However, this calculation may be incorrect if Tesla has replaced your battery or changed manufacturing processes in the middle of a model year.

For example, if you have a new car and your battery capacity is reading well above or below the fleet, it's indicative that Tesla has changed the manufacturing process for your configuration. You can find the correct value by changing the capacity until your measurements line up with the fleet average.

If degradation is high, your capacity is below average or you've lost significant max range

While every battery is different, you may be able to improve capacity and range calculations by calibrating the Battery Management System.

How can I minimize degradation?

Check out Minimizing Battery Degradation.

What amount of degradation is normal?

Maximum capacity starts to decrease immediately, and tends to stabilize around a 10% loss. Some batteries degrade slowly and level off around 100,000 mi or 150,000 km, but others may degrade and level off much more quickly.

Why was there a sudden change in capacity or range?

This can happen if a vehicle has a configuration change that affects range, like changing wheel sizes. Range may also be changed via software updates.

When this happens, it's a good idea to calibrate the Battery Management System to help it relearn how much energy is in the battery.

How are battery capacity and max range measured?

Max range is the range value displayed in your vehicle if it was charged to 100%.

Battery capacity is the "energy added" value displayed in your vehicle if you were to charge it from 0% to 100%.

Tessie continuously extrapolates these data points to monitor for changes in your battery.

How are charge cycles measured?

Charge cycles represent the number of times the battery has charged the equivalent of 0% to 100%. For example, charging from 80% to 90% ten times is one charge cycle.

For the time prior to Tessie tracking your charging data, Tessie estimates charge cycles using the vehicle's real-world energy usage patterns.

What happens if my battery gets replaced?

Tessie automatically learns your new battery. The health percentage, usable capacity and max range calculations will automatically begin adapting to the new battery. After 30 charges of 5 kWh or more, the calculations will be fully calibrated to the new battery.