How to Check EV Battery Health

Electric vehicles (EVs) are becoming a common choice for drivers who want to reduce their environmental impact.

One of the most crucial parts of any EV is its battery.

The health of this battery determines the vehicle's range, performance, and overall efficiency.

But do you know how to check EV battery health?

Understanding how to check and maintain the battery's health is essential for every motorist, especially those looking to either buy or sell a used EV.

In this article, we’ll discuss what EV battery health is, how to check EV battery health, ways to extend its life, and what to do with damaged or degraded batteries.

What is EV Battery Health?

An EV's battery health refers to its ability to hold a charge compared to when it was new.

Over time, all batteries degrade, meaning they lose capacity and are unable to provide the same range or power as they once could.

This degradation happens for a number of reasons, including how often the battery is charged, environmental conditions, and how the vehicle is driven.

Monitoring the health of your EV battery can help you understand how long your EV battery will last, when it may need replacement or repair and how well it’s performing.

Batteries in electric vehicles are typically lithium-ion, similar to those in smartphones or laptops but much larger.

As the battery ages, it holds less energy, reducing the car's driving range.

Manufacturers generally offer warranties for their batteries, often guaranteeing around 70% to 80% capacity after a set number of years.

Knowing how to check and maintain battery health will help you keep your EV running at its best for longer.

How to Check EV Battery Health

Monitoring your EV battery’s health is essential to ensure your vehicle runs efficiently and reliably.

Over time, all batteries degrade, which can reduce your car's range and performance.

Regularly checking your battery's health can help you address issues before they become significant problems.

Here are the best ways to check your EV battery’s health.

Use Your EV’s Built-In Battery Monitoring System

Most modern electric vehicles come equipped with a built-in battery management system (BMS).

This system tracks the condition of your battery and provides updates on its performance.

Accessing the BMS is one of the easiest ways to check your EV battery's health.

Simply use the display on your dashboard or access it through your car’s app. This system often shows:

• Battery charge status

• Estimated range

• Battery temperature

• Charging history

By regularly reviewing the information, you can spot any unusual changes, such as a sudden drop in range or slower charging times, which could indicate issues with battery health.

Check the Battery’s State of Health (SoH)

The State of Health (SoH) refers to how much capacity your battery retains compared to when it was new.

For instance, if your EV battery had a capacity of 100 kWh when new and now it has only 90 kWh of usable energy, the SoH would be 90%.

Most EV manufacturers provide a way to check the SoH through the vehicle’s dashboard or connected apps.

You may also find this data when you take your vehicle in for regular servicing.

An SoH of 70% to 80% is generally acceptable for older vehicles, but a significant drop below that may suggest the battery is ageing and not holding a charge as well as it should.

Conduct a Full Charge and Range Test

One practical way to assess your battery health is by conducting a full charge and range test.

Fully charge your EV and drive it until the battery is nearly depleted.

Compare the distance driven to the original estimated range of your vehicle when it was new.

If your EV is not covering the distance it once did, it could be a sign of diminished battery health.

Remember, driving conditions, temperature, and terrain can all affect range, so make sure to test in conditions similar to how you normally use the vehicle.

Monitor Charge Time

As batteries age, they often take longer to charge.

Pay attention to how long your EV takes to charge from one level to another.

If charging seems to take significantly longer than when the car was new, it could indicate the battery is degrading.

Charging time can also vary based on the type of charger you use.

If you notice a consistent increase in charging time across different chargers, this is a clearer sign of potential battery issues.

Use a Third-Party Diagnostic Tool

Several third-party diagnostic tools are available to help monitor your EV battery health.

These tools connect to your car's OBD-II port (the same port mechanics use to diagnose car problems) and provide detailed information about the battery, such as charging cycles, voltage levels, and more.

Tools like LeafSpy for Nissan Leaf or Teslafi for Tesla vehicles can offer even more insights than your car’s native monitoring system.

Have Your Battery Professionally Tested

If you're concerned about your battery health or if it’s showing signs of deterioration, it’s a good idea to get it professionally tested.

Many auto repair shops that specialise in electric vehicles can run a battery diagnostic test.

These tests can identify potential problems like cell degradation, thermal issues, or improper charging.

A professional test can provide peace of mind, especially if you're planning to sell your vehicle or want to ensure your battery warranty remains valid.

Look for Warning Signs of Degradation

Batteries don’t usually fail overnight.

There are often several warning signs that indicate battery health is declining. Look out for the following symptoms:

• Reduced Range: Your car no longer travels as far on a single charge.

• Slow Charging: Charging takes noticeably longer than it used to.

• Overheating: The battery becomes excessively warm, which can indicate internal issues.

• Erratic Behaviour: Sudden drops in charge percentage or the car shutting down unexpectedly.

If you notice any of these signs, it's worth checking your battery’s health more thoroughly and seeking professional advice if needed.

How Can You Extend EV Battery Life?

Extending the life of your EV battery can save you money and improve your car’s efficiency.

With proper care and attention, you can help your EV battery last longer. Here are some key tips to prolong its life.

Avoid Frequent Fast Charging

While fast charging is convenient, using it too often can degrade your battery faster.

Regular charging at slower speeds is gentler on the battery, helping to maintain its long-term health.

Don’t Let Your Battery Fully Drain

It’s best to avoid letting your EV battery drop to 0% charge to maximise EV battery health.

Keeping it above 20% can prevent excessive wear.

Similarly, charging your battery to 100% all the time can cause stress.

Keep the charge between 80% and 90% for optimal EV battery health.

Charge in Cooler Temperatures

Extreme heat can damage EV batteries over time.

If possible, charge your vehicle in cooler environments, especially during hot summer months.

Parking in shaded or cool areas can also help protect the battery.

Monitor Your Driving Habits

Aggressive driving, such as sudden acceleration and harsh braking, can put extra strain on your battery.

Knowing how to drive an electric car properly, where you drive smoothly and at consistent speeds can help reduce battery wear.

Regularly Update Your Vehicle’s Software

Many EVs have software that manages battery health.

Keeping this software updated ensures that the battery is optimised for performance and longevity.

Store Properly During Long Periods of Inactivity

If you're not using your EV for an extended period, keep the battery charge around 50%.

Storing a fully charged or fully drained battery can accelerate degradation.

What to do With Old EV Batteries

When an EV battery reaches the end of its life, it’s essential to handle it responsibly.

EV batteries are large and contain hazardous materials, so they should not be thrown away.

There are a few options for dealing with old EV batteries, and some can even give them a second life.

Recycling EV Batteries

Recycling old EV batteries is the most eco-friendly option when your EV battery fails.

Many recycling centres are equipped to handle lithium-ion batteries, which are common in EVs.

These centres break down the batteries to recover valuable materials like lithium, cobalt, and nickel.

This process reduces the need for new raw materials, which helps the environment.

Repurposing EV Batteries for Energy Storage

Old EV batteries may no longer work well for driving, but they can still store energy.

Some companies repurpose these batteries for home energy storage systems.

For example, they can store energy generated by solar panels, offering an alternative use before recycling.

Returning Batteries to Manufacturers

Many EV manufacturers offer take-back programs for old batteries.

When you buy a new EV or replace your old battery, check with the manufacturer about returning your old one.

This helps ensure proper recycling or repurposing.

Donating or Selling for Research

Old EV batteries can also be useful for research and development.

Some institutions buy or accept donations of used batteries for testing and further development of battery technology.

Conclusion

You should now have more of an understanding of how to check EV battery health.

Maintaining your EV battery’s health is crucial for ensuring your vehicle performs well for years to come.

By regularly monitoring the battery’s condition, following best practices to extend its life, and knowing what to do when it degrades, you can keep your EV running smoothly.

Whether you're using your car for daily commuting or long trips, staying informed about your battery’s health will help you get the most out of your electric vehicle.

For more help on EVs in general, or for information on how you can rent out your EV changer, then get in contact with us at Joosup.