With so many EV drivers joining the roads (over 4 million and counting), the available public charging infrastructure isn’t keeping up with the EV boom. That leads the majority of drivers to want to charge their electric cars at every opportunity. But does that mean you juice up multiple times as long as your battery level is around 30 to 50%? Does charging frequently go against EV battery charging best practices?
Observing the recommended charging practices not only ensures you get the best range between charges but also protects your EV battery from deterioration. Just know that the battery is the most expensive part of your electric car. So, you want to keep it healthy through the best charging practices. Even though lithium-ion (Li-ion) battery technology in your EV keeps improving, they still lose their charge retention capacity at about 2.3% per year. That calls for the need to maintain their health so your EV can serve you for longer.
What’s the Durability of EV Batteries?
One important point you need to bear in mind when it comes to EV battery health is their durability. Comparing research data from 2019 and 2024, it’s revealed that EV battery lifespan has improved. According to GEOTAB, batteries in 2024 had a degradation rate of 1.8% per annum.
If the rate of degradation stays constant, EV batteries can last up to 20 years, or more, depending on individual usage. But even with the annual degradation rate, most EVs can retain their range for at least a decade.
So, that begs the question: what accelerates EV battery degradation? Well, it boils down to two main factors:
- Repeatedly driving your EV to near zero charge, then recharging from near zero to full charge.
- Continually charging your EV battery using DC Fast Charging, also known as Level 3 charging.
Some EV manufacturers, like KIA, even suggest that you shouldn’t rely solely on DC Fast Charging as your primary charge source.
Top 10 EV Battery Charging Best Practices
We’ve seen the two leading causes of EV battery degradation. But what are the recommended practices to maintain better battery health and get the full range? Here, we take a look at EV battery maintenance guidelines to optimize your electric car’s battery health.
Maintain the 20-80% Charge Level Rule
Lithium-ion batteries, whether for your smartphone, laptop, or electric car, can maintain a prolonged lifespan if the charge level doesn’t exceed 80% or go lower than 20%. Charging the battery regularly beyond 80% eventually reduces the range.
Batteries are nothing but a chain of chemical reactions that generate electricity. when almost or fully charged, the stored energy can trigger other unintentional reactions, the dangerous ones. Over time, these dangerous chemical reactions reduce the capacity and efficiency of the battery.
Generally, Li-ion batteries perform poorly when they’re at a low charge state and better over a long period when they’re only recharged partially in each discharge cycle. So, maintaining a 20-80% charge rule is kinder and will give your battery a longer life than 0-100%.
Charge Batteries Regularly
This is one of the most recommended EV battery charging best practices, especially if you don’t use your electric car that much. If the EV spends lots of time in the garage, your battery’s health risks degradation. Also, don’t wait until the battery level is almost zero to recharge.
Deep discharges accelerate battery degradation, so charging regularly avoids situations where your battery is fully drained. You can conveniently top up at home overnight, especially during off-peak hours when rates are cheaper.
Don’t Build Over-Dependence on Level 3 Charging
Battery experts recommend using Level 1 and Level 2 chargers over Level 3, especially if it’s your primary charge source. A DC fast charger (Level 3) is more convenient because it takes only a few minutes for your battery to charge to optimal levels. However, this shouldn’t be the primary source of charge for your EV due to the higher currents generated, plus extra heat, which speeds up degradation.
Therefore, if you haven’t, install a Level 2 charger for your home use—this is a worthwhile investment that will meet your daily charging needs. Only rely on public DC fast chargers during emergencies or when running late.
Avoid Exposure to Prolonged Extreme Temperatures
When your EV battery is exposed to temperatures below 32°F or above 86°F, its health is also affected. Ensure your car is parked in a shaded area or inside the garage to prevent exposure to extreme cold or heat.
Also, charging or driving your EV in high or low temperatures can expose the batteries to extra wear and tear, which can also affect the range. The high currents in DC fast charging can also exacerbate the degradation due to heat.
However, the modern EVs automatically lower the battery temperature to an ideal level for charging once you select a DC fast charger in your navigation system. This is referred to as battery preconditioning. Take advantage of this by ensuring you pick your charger at least half an hour early before plugging in. this gives the battery enough time to attain the right charging temperature.
Use Regenerative Braking
Regenerative braking (Regen) is a feature of EVs where the kinetic energy of the vehicle is captured, converted into electrical energy when a driver applies brakes. This energy is stored and later used for powering the vehicle.
This enhances efficiency while reducing strain on your EV battery. Actually, regenerative braking is automatic, and no action is required from a driver. However, you can adjust the regeneration level to your preferred setting.
Regen activates when you ease the pressure on the accelerator, step on the brake pedal, or when going downhill and the gravitational force increases your car’s speed without applying more pressure on the accelerator.
Don’t Overcharge Your EV
We’ve already talked about maintaining a 20-80% charge rule as one of EV battery charging best practices. But sometimes, you need every bit of charge you can get in readiness for a long trip, in that case, charging to 100% is acceptable. This doesn’t mean that you overcharge as doing so only puts your battery under stress, especially from overheating.
While most modern EVs come with built-in systems that prevent overcharging, it doesn’t hurt to just avoid it altogether. Alongside caring for your battery, proper maintenance of EV charger is equally important to ensure safe, efficient, and long-lasting performance.
Watch your Driving Habits
Just like with gasoline vehicles, hard braking and sudden acceleration put extra stress on the vehicle. Instead, take advantage of features such as adaptive cruise control to minimize the strain on your EV batteries.
Avoid Fast Charging Immediately After Long Trips
It’s common practice to want your electric car to be fully charged after completing a long drive. At this time, the battery is a bit hot or warm, so it’s not the ideal time to recharge with a Level 3 charger. give it some time to cool before starting a fast-charging session. This can prevent overheating, considering rapid charging also produces heat due to the high current.
Monitor Your Battery Health
Keeping your battery health in check at all times is also another EV battery charging best practice you should keep up with. Most electric cars have a battery management system (BMS), allowing you to read crucial data about the battery, including its health and state of charge. Keep up with this information to address problems immediately whenever they pop up and prolong your battery life.
Monitoring the state of charge can help you plan your charging sessions, especially when on a long trip. Some BMS apps can also show the charging efficiency data. Keep monitoring these metrics to measure your battery health over time.
Don’t Ignore Software and Firmware Updates
No matter how busy you are, spare a few minutes to run updates whenever your EV manufacturer rolls them out. Maintaining an up-to-date state of your BMS software and firmware can help optimize your EV battery performance.
Some of these updates can feature BMS enhancements, energy management, and charging algorithms. Moreover, your EV maker also provides tips and guidelines about software updates and charging practices. Following these recommendations is an excellent way of optimizing your charging process.
Regularly run update checks and install them as required by OEM instructions to maximize your charging efficiency and overall battery lifespan.
Driving a Tesla and wondering whether any special rules apply specifically to this brand? Well, the best charging practices for Tesla are similar to those for any other EV out there. In short, treat your Tesla like you would any other EV—maintain the 20-80% rule, don’t overcharge, take advantage of regenerative braking, and everything else we’ve talked about here.
Final Words
Adhering to these EV battery charging best practices is crucial for maintaining good battery health and lifespan. So, take note of the common mistakes EV drivers make, such as deep charging from 0 to 100%, relying on DC fast chargers as the primary charge source, and overcharging.
Following these EV battery maintenance guidelines can help your EV battery last longer, have better efficiency while you enjoy a smoother driving experience.