How to check your Tesla battery’s actual health and know if it’s aging well?

Your Tesla has some miles on the odometer, and you’re wondering how its battery is aging? I’ll show you how to monitor your Tesla battery’s health like a pro.

The battery is the heart of your electric vehicle, and monitoring its health isn’t paranoia: it’s a smart move. Several methods exist to check actual degradation, and I’ll present them all to you.

Rest assured: slight degradation is perfectly normal, and Tesla manages it remarkably well. In this article, I’ll show you the native Tesla app methods, manual calculations you can perform, and third-party tools that will give you precise data.

Why monitor your Tesla battery’s health?

Understanding the battery’s natural aging is essential to staying calm. Typically, you’ll observe a 1 to 5% loss in the first year, followed by a gradual slowdown. This is an inevitable physical phenomenon with lithium-ion batteries.

This degradation has a direct impact on your real-world range in daily use. If you had 500 km of driving range initially and now have 480 km, you know exactly what to expect for your trips.

Another often-overlooked aspect: resale value. A healthy battery greatly reassures potential buyers and can make a difference during negotiation. Detecting potential anomalies early also allows you to act before the problem worsens.

Note that Tesla guarantees 70% capacity for 8 years or 160,000 km minimum, depending on the model. This is an excellent safety net.

What’s normal vs. what should raise concern

Normal degradation is around 2 to 3% in the first year, then about 1% per year thereafter. The degradation curve is not linear: it’s more pronounced at the beginning, then stabilizes.

Several factors influence this aging:

• The frequency of fast charging at Superchargers
• Extreme weather conditions (extreme cold or high heat)
• Charging habits (leaving the battery at 100% or 0% for extended periods)
• Driving style (repeated harsh accelerations)

When should you worry? A sudden loss of driving range or a drop greater than 10% in a short period warrants a check. In this case, contact Tesla service.

Check health from the Tesla app

The simplest method is to check the driving range displayed at 100% charge. This is accessible directly on the vehicle’s charging screen or via the mobile Tesla app.

Compare this value with your model’s nominal WLTP driving range when it was purchased. For example, a new Model 3 Long Range displayed approximately 614 km of WLTP driving range when it was released.

Beware of this method’s limitations: it’s an approximate estimate that fluctuates depending on the outside temperature, your recent driving style, and even software updates. Don’t panic if you see 10 km less on a winter morning.

Calculate the actual degradation percentage

To get a more precise view, use this simple formula:

(Current driving range at 100% / Original driving range) × 100 = Battery health percentage

Concrete example: you have a Model 3 Long Range that originally displayed 614 km and now displays 580 km at 100%. The calculation gives: (580 / 614) × 100 = 94.5% battery health, or 5.5% degradation. This is perfectly normal after a few years of use.

Practical tip: take several readings at different times to get a reliable average. Tesla software updates can sometimes change the display without the actual capacity having changed.

Use third-party tools and apps for accurate diagnosis

If you want to go beyond the basic display, several tools exist to get detailed data on your Tesla battery’s health.

TeslaFi is a web service that connects to your Tesla account and offers detailed tracking of degradation over time with very visual graphs. You can see the evolution month by month.

Scan My Tesla is a mobile app that connects via an OBD adapter to your Tesla’s diagnostic port. It provides access to very precise data normally reserved for technicians.

TeslaMate is an open-source solution for the more tech-savvy among you who want to analyze everything and host their own data. The installation is a bit technical, but the results are impressive.

Stats (iOS app) offers simplified battery monitoring with a clear and accessible history, ideal if you’re not a fan of overly complex data.

Interpreting advanced data

With these tools, you access information such as nominal capacity vs. usable capacity. Tesla never lets you use 100% of the physical capacity: a safety margin is reserved at the top and bottom to protect the battery.

The BMS (Battery Management System) plays a crucial role. It’s the brain that manages each battery cell, balances them, and optimizes charging/discharging to maximize lifespan.

Key data to monitor include:

• Available kWh (actual usable capacity)
• Cell voltage
• Battery temperature
• Module balancing

To further understand and optimize your Tesla battery’s lifespan, I recommend discovering the little-known secrets that can make all the difference in the long run.

My practical tips for monitoring and preserving your battery

Establish a simple routine: take a monthly reading under similar conditions. Note the date, mileage, and driving range displayed at 100%. Always choose the same time (for example, after a night in the garage) so the temperature is comparable.

Keep a simple logbook, even in a note on your phone. This way, you can visualize the trend over several months and detect any anomalies. An Excel or Google Sheets spreadsheet works perfectly.

Don’t panic over variations of 5 to 10 km depending on the season. The displayed driving range takes into account the outside temperature and your recent driving habits. It’s normal to see less in winter.

Use preconditioning before fast charging at a Supercharger: the car heats the battery to the optimal temperature, which reduces thermal stress and preserves its health.

Good habits that slow down aging

The golden rule: charge between 20% and 80% daily. This is the range where the battery is happiest. Reserve 100% charges for long trips where you truly need them.

Limit fast charging at Superchargers. They are convenient for travel but put more strain on the battery than slow charging. For daily use, always prioritize home charging on a reinforced outlet or wallbox.

Avoid leaving the battery at 100% or 0% for several days. If you’re not driving for a week, leave it closer to 50%. Tesla even recommends keeping the vehicle plugged in permanently so the BMS can manage balancing.

To discover all the techniques that can prolong your battery’s life, consult our dedicated guide which details the best practices validated by the experience feedback of thousands of owners.

If you’re considering buying a used Tesla, battery health will obviously be your main concern. Learn how to evaluate the condition of a used Tesla to negotiate with full knowledge and avoid unpleasant surprises.

What to do if your battery degrades abnormally?

If your readings show abnormal degradation, start by contacting Tesla service with all your data. The more documented measurements you have, the stronger your case will be.

The Tesla battery warranty generally covers 8 years or 160,000 to 192,000 km depending on the model, with a minimum of 70% capacity retention. If you are below this threshold during the warranty period, Tesla must intervene.

Sometimes, the problem simply comes from the BMS needing recalibration. Tesla technicians can perform this operation, which precisely recalculates the actual capacity without physically touching the battery.

Cases of full replacement under warranty exist but remain rare. Tesla takes these situations seriously, based on my experience and that of many owners I know. Customer service is generally responsive on these issues that affect the core of the vehicle.

My advice: keep a written record of all your exchanges with Tesla (emails, tickets, calls). Note the dates, names of contacts, and responses obtained. This documentation can prove invaluable if the case needs to be escalated.

To deepen your understanding of lithium-ion battery aging and technical aspects, you can consult specialized tools that explain the physicochemical mechanisms involved.

Now that you know how to monitor your Tesla battery’s health, make it a habit to take regular readings. Most of the time, you’ll find that your battery is aging remarkably well. And if you detect a problem, you’ll have all the information you need to act quickly. Feel free to share your experience and your own readings in the comments: it helps the entire Tesla community get a realistic view of battery aging!