Tesla automatically setting LFP battery charge limits to 100% to prevent 12V Li-Ion batteries from failing

battery notification
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Earlier this week we told you about some new Tesla owners who were experiencing their 12V Li-Ion batteries failing when the vehicle’s main battery was at a low state of charge (SOC).

The problem was caused by the lithium iron phosphate (LFP) battery not being properly calibrated, which would lead the computer to think it still had some energy left in it when it was actually empty.

According to an internal service memo, the recommended fix was to simply charge the LFP battery to 100% to properly calibrate it.

The issue even caught the attention of Elon Musk, who said on Tuesday Tesla was “investigating.”

Today it appears they have figured out a simple but effective way to try and prevent it from happening by automatically adjusting the charge limit on certain cars to 100%.

Tesla is using the vehicle’s connectivity to send an in-car notification alerting owners to the change.

“The charge limit in your vehicle has been automatically adjusted to 100% in order to perform battery calibration.

Please charge your vehicle at the earliest opportunity and allow it to continue until “Charging Complete” is displayed to maximize the performance of your battery.”

UPDATE March 5 8:35am PST: It looks like Tesla has updated the message to be more specific as to the reason for the calibration, and added a recommendation to charge to 100% at least once per week.

“The charge limit in your vehicle has been automatically adjusted to 100%. The range display in your vehicle is undergoing calibration. Until calibrated, displayed range my under or overestimate compared to distance driven.

To improve accuracy, charge to 100%. It is recommended for this configuration of vehicle to keep your charge limit set to 100%, even for daily use, and that you also fully charge to 100% at least once per week.”

According to a Model 3 owner in Canada who received the message, they only took delivery of their car 3 weeks ago, and had not yet charged to 100%.

This could mean Tesla is targeting those vehicles that haven’t yet calibrated their LFP batteries.

Have you received this message? Have you previously charged to 100%? Let us know in the comments below.

About Darryn John 4464 Articles
Founder and Editor-in-chief of Drive Tesla Canada | Darryn@DriveTeslaCanada.ca Have a Tesla tip? Email tips@driveteslacanada.ca, or DM us on Twitter @DriveTeslaca