How to check EV battery State of Health (SoH)

If you are driving an electric car, you know that the battery is like the heart of the car. But just like a human body, the EV batteries naturally degrade with time.

Thus it is important to know how to check your EV battery’s State of Health (SoH), whether you are trying to increase the efficiency of your car or looking for a highly reliable EV car, knowing your car’s SoH is really crucial in order to determine its current performance. Let’s understand EV battery health and proper ways to check it. 

What exactly is Electric Car Battery Health? 

The Electric car battery health determines the current energy capacity which is compared to when it is dispatched fresh off from the factory floor. Just understand your battery capacity as kilowatt-hours (kWh), just like an ICE car’s fuel tank. Over-time it naturally degrades by about two to three percent per year totally depending on your personal driving habits, charging and local climate. 

Simply put it to 100% State of Charge (SOC) for today and you might get less range that you had got three years ago. While this much amount of degradation is completely normal, thus it is important to regularly check your battery’s SoH which just ensures you don’t get sudden drop in your daily range and performance.

How to check EV Battery Health?

You just don’t need to be a master EV technician in order to check your EV’s battery. Here are some tips you can use directly from your driver’s seat. 

Dashboard Range Estimation: Your car’s dashboard is your first meter for reading for your range as it provides the actual range you can drive with the battery fully charged, thus giving a rough estimation of your car’s performance. Just take a note that your driving style, terrain, and even cold or hot climate will directly affect your range numbers. 

State of Charge (SOC) Measurement: Just have a watch how the SOC percentage drops during the regular drive. While it doesn’t give you a clear idea of SoH percentage, a rapidly declining battery is a clear sign of reducing efficiency and is a great metric to monitor during a test drive. 

Battery Management System (BMS): Many Modern EVs come equipped with a built-in BMS. What it does is it continually monitors the battery temperature, voltage, and current, providing a real-time battery condition indicator directly on your infotainment screen.

Software and Diagnostic Tools for Accurate SoH Measurement

You want a more accurate and precise measurement, here are some more specialised tech which can provide SoH in a proper reading. 

OBD2 Readers & Scanners

Every modern electric car features an On-Board Diagnostics (OBD2) system. Thus by connecting any affordable OBD2 scanner into OBD2 diagnostic port, you can get detailed Diagnostic Trouble Codes (DTCs) and provide real-time accurate data of your EV’s battery health. 

Manufacturer & Third Party Apps

Many manufacturers are providing dedicated smartphone apps that connect seamlessly to the car via built-in cellular telematics for a detailed inspection of your history, charging data and capacity. There are various third party apps (Leafspy, ABRP, & Recurrent) that typically require a separate OBD2 dongle. 

On the other hand, there is also an availability of smart third party apps like ClearWatt which uses mobile telematics and AI to bring a rough estimate of your real-world range. The ClearWatt comes with a ‘Subscription’ for a specific testing period. What’s the most interesting part? They automatically remove various factors for high accuracy. 

Professional Diagnostic Scans 

There are various certified service centers which have trained technicians that use advanced diagnostic tools to provide cell resistance and overall health, providing you the complete analysis of your EV’s battery health.

The Final Verdict 

Thus taking care of your EV’s batteries is not just a guessing game anymore, as by using these techniques and carefully checking your car’s batteries regularly, you can confidently ensure solid reliability of your EV’s battery.