EV Battery in Hot Temperature: 5 Things to Know

As the automotive industry accelerates towards electric vehicles as a sustainable mode of transportation, the performance and longevity of electric vehicle batteries become a crucial consideration.

One of the challenging aspects impacting EV batteries is their behavior in hot temperatures.

In this article, we delve into the intricacies of how high temperatures affect EV batteries, exploring five essential things every EV owner and enthusiast should know.

Does Temperature Affect EV Battery Life?

Yes, high temperature affects EV battery life. If the battery temperature is higher than 30°C, or 86°F, it can lead to a higher rate of degradation of the battery components, particularly the electrodes and electrolytes. This results in a reduction of the battery’s overall capacity.

The effect of high temperature on EV battery life is a multifaceted phenomenon rooted in the electrochemical processes within the battery cells. Let’s discover more:

Chemical Reactions and Degradation: At higher temperatures, the chemical reactions within the battery cells occur at an accelerated rate. This increased reactivity can lead to a higher rate of degradation of the battery components, particularly the electrodes and electrolytes. Over time, this degradation results in a reduction of the battery’s overall capacity.

Thermal Runaway: Extreme heat can trigger thermal runaway, a self-perpetuating reaction that generates more heat and can ultimately lead to catastrophic failure. This phenomenon is a serious concern for battery safety, and manufacturers implement various thermal management systems to mitigate this risk.

Capacity Loss: High temperatures contribute to accelerated capacity loss. The battery’s ability to store and deliver energy diminishes more rapidly in elevated temperatures, affecting the driving range of the electric vehicle.

Charging Challenges: Charging an EV in high temperatures can exacerbate the stress on the battery. Rapid charging generates additional heat, and if the battery is already exposed to high temperatures, it can lead to a further decline in performance and lifespan.

How Does Hot Weather Affect EV Range?

According to estimates, EV range can experience a significant 15-17% drop when temperatures soar above 35°C, or 95°F.

Capacity fade is accelerated in high temperatures due to the increased stress on the battery components. Here are some reasons behind this:

Sluggish Electron Movement: In hot weather, the performance of EV batteries is hindered by the sluggish movement of electrons. Higher temperatures cause a reduction in the speed of electron flow within the battery, resulting in a diminished power output. This directly affects the overall range of the electric vehicle.

2. Lack of Combustion Engine Cooling: Unlike traditional vehicles with internal combustion engines that dissipate heat efficiently, EVs lack a similar mechanism. The absence of an engine to naturally disperse heat poses a challenge for the battery’s temperature regulation. Without effective cooling, the battery is susceptible to overheating, leading to a decrease in range and potential long-term damage.

3. Charging Challenges: The act of charging itself can contribute to overheating. EVs often incorporate systems that monitor battery temperature during charging, implementing “thermal throttling” if excessive heat is detected. This automatic reduction in charging speed helps manage heat generation, preserving the battery’s integrity. Owners are encouraged to charge their vehicles during cooler periods to prevent unnecessary stress on the battery.

Lithium-ion batteries used in EVs, perform optimally within a specific temperature range—ideally between 26-35°C (68 to 86°F). More than 35°C (86°F) can lead to higher rate of degradation of the battery components, which impacts long and short term battery longevity.

Important: EV battery replacement can cost $1000s. To avoid high-voltage battery replacement, there are some things you can do. Read this article to find out the 10 best ways to maximize EV battery life and save tons of money!

How Do I Keep My EV Battery Cool in the Summer?

If the temperature is hot, it’s advisable to cool down the EV battery. Here are practical steps to keep your EV battery cool during the sweltering summer months:

1. Strategic Parking: Whenever possible, park your EV in shaded areas to shield it from direct sunlight. This simple yet effective measure helps prevent unnecessary heat absorption by the battery, maintaining a more moderate temperature.

2. Preconditioning: Many modern EVs come equipped with a preconditioning feature that allows you to cool the interior and, importantly, the battery before starting your journey. This not only enhances comfort but also ensures the battery begins its operation at an optimal temperature.

3. Avoid Extended Sun Exposure: Prolonged exposure to direct sunlight, even when parked, can elevate the internal temperature of the EV. Minimize the duration your vehicle spends under the sun to reduce the risk of overheating.

4. Optimal Charging Times: If possible, schedule your charging sessions during the cooler parts of the day or evening. Charging during lower ambient temperatures reduces the stress on the battery, as the heat generated during charging is less likely to push the temperature beyond optimal levels.

5. Battery Management System: Leverage the built-in battery management system of your EV. Many electric vehicles are equipped with sophisticated thermal management systems that actively monitor and regulate the temperature of the battery. Trust these systems to automatically adjust settings for optimal performance.

6. Adequate Charge Levels: Maintaining an adequate level of charge is crucial in preventing excessive heat buildup. A fully charged battery tends to stay cooler for a more extended period. Before embarking on a journey in the heat, ensure your EV is sufficiently charged.

7. Limit Fast Charging in Extreme Heat: While fast charging is convenient, in extremely hot weather, it can contribute to increased heat generation. If possible, moderate the use of fast charging during the hottest parts of the day to prevent unnecessary stress on the battery.

Also read: EV Battery in Hot Temperature: 5 Things to Know

Can it Be Too Hot to Charge an Electric Car?

Generally charging your EV below 35°C (86°F) shouldn’t harm the battery. However, when the temperature is hotter, you should consider some steps to prevent battery degradation.

Here’s everything you should keep in mind about charging your EV in hot weather.

1. Battery Thermal Management: Most EVs are equipped with battery thermal management systems designed to regulate temperature during charging. These systems include sensors and controls to monitor and adjust the charging process, ensuring the battery remains within a safe temperature range.

2. Thermal Runaway Risk: In extremely hot conditions, there is a risk of thermal runaway—a self-perpetuating reaction that generates more heat. While modern EVs have safety mechanisms to prevent this, charging during the hottest parts of the day may increase the likelihood of heat-related issues.

3. Reduced Charging Speed: High temperatures can trigger thermal throttling, where the charging speed is automatically reduced to manage heat generation. While this protects the battery, it can extend the charging time, necessitating planning for longer charging sessions.

4. Avoiding Peak Heat Times: To mitigate the impact of high temperatures, consider scheduling charging sessions during cooler parts of the day or evening. This helps minimize stress on the battery and ensures more efficient charging.

5. Monitoring Battery Temperature: Many EVs provide real-time information about battery temperature during charging. Utilize this feature to stay informed and make informed decisions about when to initiate or pause charging.

6. Fast Charging Considerations: While fast charging is convenient, it can generate more heat. During scorching temperatures, consider moderating the use of fast charging to prevent excessive stress on the battery.

7. Battery Health Considerations: Charging in extreme heat regularly over an extended period can contribute to accelerated battery degradation. It’s essential to balance the convenience of charging with the long-term health of the battery.

Tip: The best temperature to charge most EV batteries is 15-30°C (59-86°F).