100 or 90%: How much do you charge as a Tesla driver?

Have you ever wondered why the charging speed of electric cars is often given in "x minutes from 0 - 80%" and not "up to 100%"?

Charging a Tesla correctly

Different charging recommendations

Well, firstly, this naturally allows for significantly shorter charging times – but there's also a technical reason. Due to their chemical properties, batteries lose some of their capacity over time. Depending on how far and how intensely the battery is charged, this process can be accelerated or slowed down.

Maximum everyday charging capacity

But how far should you charge the battery at most? Tesla recommends charging the battery to a maximum of 90% in everyday use and only using its full capacity when you actually need it for a longer trip. This guarantees the longest possible lifespan and also reduces the average charging time: Due to the cell chemistry, the charging current drops rapidly above 80% charge, meaning the first 80% is reached much faster than the remaining 20%.

Tips for charging management

Knowing this, it's helpful that you can set a maximum daily charge level in a Tesla's charging management system. By the way: If the vehicle is parked for an extended period, the charge level should be kept between 20 and 80%; anything higher will damage the battery.

Charging frequency vs. charging cycles

While the amount you charge the battery to is certainly relevant, contrary to popular belief, the frequency of charging is almost irrelevant. What matters for a battery is the number of charge cycles, which describes how many times it is fully charged from 0 to 100%. Someone who charges by 20% on five days doesn't "use up" five charge cycles, but only one. Accordingly, Tesla itself recommends simply recharging the battery to 90% every day.

Charging speed and Battery types

However, what is relevant for battery lifespan is how strongly or quickly the battery is charged. Fast charging stations such as... Tesla Superchargers, with their charging capacities of several hundred kW, are excellent for saving time. However, they are rather detrimental to the battery, which prefers lower power levels such as the 3 kW of a standard household outlet. Since this also has disadvantages (relatively high charging losses, safety issues, prolonged activity of the onboard computer during charging, and the battery not getting properly warm), charging at a wallbox with 11–16 kW is the ideal compromise.

Important: Many of these guidelines apply only to vehicles with NCA batteries, meaning all older models as well as Performance and Long Range versions. Newer Standard Range Teslas with LFP batteries generally have different recommendations.

Do you have experience with your Tesla's charging practices? Share your thoughts and tips in the comments below.