Most of us, influenced by our experiences with smartphones and laptops, might wonder if electric vehicles (EVs) will quickly succumb to declining battery health. The fear is natural; no one wants their new EV to rapidly lose battery performance, akin to how our phones do. The reality, however, is a lot more promising for electric cars.
How do lithium batteries work?
Just like portable electronics (mobile phones, laptops, etc.), most electric cars use rechargeable lithium-ion batteries with complex mechanisms for multiple reasons. They charge faster and store more energy compared to previously invented battery technologies. Moreover, they take up less space while holding more power. Over time, though, these batteries start to degrade naturally, leaving us with a device whose capacity is diminished and bugging us for constant recharge.
Why does my EV battery last longer?
Although both EVs and personal gadgets employ lithium batteries, the comparison, for the most part, ends there. In fact, while the ‘healthy’ period of a smartphone battery lasts around 2-3 years for a regular user, recent studies show that most EVs do not require any replacements even after their (typical) 8-year and 100,000-mile warranty.
To mitigate rapid degradation, electric car batteries come with specific design adjustments: advanced thermal management systems and ‘buffer zones’. These innovations ensure that, unlike your phone, which might need more frequent charging after a year or two, most EVs won’t leave you tethered to the charger.
That said, there are always outliers, where EV battery degradation occurs at a faster rate, often influenced by driving and charging behaviours. ClearWatt’s EV Battery Health Checker identifies these outliers, providing full transparency during resale.
Solution #1: Thermal Management
Understanding the thermodynamics of lithium-ion batteries is crucial to discerning the unequal degradation patterns between EVs and consumer electronics. At their core, all lithium batteries are sensitive to temperature, and their optimal operating temperature lies typically between 15 to 35 degrees Celsius. Deviating from this range can accelerate battery degradation. At this point, a clear distinction arises: EVs are equipped with advanced thermal management systems, while most consumer electronics remain without.
Recall the experiences of your smartphone unexpectedly shutting off on a cold night or the urge to put it in the freezer before it spontaneously shuts down during an intense heatwave. These aren’t just quirks of your device; they underscore the lack of temperature regulation inside consumer electronics. In fact, when you consider where we often keep our mobile phones (our pockets), where the temperature sustains 37 degrees Celsius, we unknowingly exacerbate battery degradation.
Enter the realm of ‘thermal management’ - the suite of processes designed to control heat flows within devices. For EVs, this becomes even more important, and the manufacturers know this. EVs require their batteries to be cooled during hot seasons and heated when it’s cold. Maintaining batteries at room temperature not only maximises vehicle driving range but also prolongs the battery’s lifespan!
Solution #2: Buffer Zones
Now that we’ve delved into thermodynamics, let’s explore another crucial difference - buffer zones, which are essentially safety margins for batteries. Simply put, by not letting the battery charge to its absolute maximum or discharge completely, its lifespan and overall health can be significantly upheld.
Devices like smartphones and laptops are geared towards frequent use. Manufacturers design them for optimal performance throughout their expected lifespan. For the everyday user, the primary focus is on device utility rather than preventing gradual battery degradation.
You wouldn’t want to charge your brand-new phone repeatedly during the day, would you? When your smartphone or laptop indicates it’s at 100%, it often genuinely approaches its maximum limit. As you use it, the device is likely to discharge near its lowest limit to maximise its operational time between charges.
With EVs, the battery management approach is fundamentally different. Given the larger size, higher cost, and crucial role of an EV’s battery, its long-term health is of paramount importance. So, while your EV’s dashboard might display a ‘fully charged’ status, in reality, there might still be a buffer in place, meaning the battery could only be charged up to 90% of its total capacity. Conversely, even if the dashboard indicates 0%, there’s a safety net, ensuring it doesn’t discharge below a set threshold, say 10%.
Conclusion
To sum up, we’ve become accustomed to seeing our beloved smartphones and laptops diminish in performance over time, leading us to question the longevity of prospective EV investments. But why do EV batteries last longer than smartphone batteries? The existence of thermal management systems and buffer zones sets EVs apart: average battery degradation rates per year for EVs stand at only 1.5%, with some older and more popular models needing quicker battery replacements.
However, it is essential to acknowledge that despite these leaps in technological innovations, there are some factors that could still result in rapid battery degradation, such as the constant use of rapid charging stations and how and where the vehicle is kept.
Whether you’re buying or selling a used EV, our app-based EV Health Checker provides complete transparency during the resale process, identifying outliers and unlocking confidence in the used EV market. And if you’re keeping your EV for a while, our easy and quick solution will help you conduct routine tests to enable proactive and preventative steps to keep your car in tip-top condition.
