31Mar 2020

While the current situation has put us all in unfamiliar territory, one bright spot has been the willingness of so many people and organizations to offer advice and assistance. With hundreds of millions of us isolated in our homes, making especially intensive and important use of our phones and computers, it seems like an opportune moment to share four battery-specific recommendations that can help ensure your personal safety and extend the lifespans of all our devices as we adjust to this period of uncertainty, and WFH normalcy.

First, and most imperatively in the near term, never ignore a battery that is swelling. This can happen over the course of just a few days, especially in aging devices, and is a sign of internal failure that can put you and your family at risk of fire or injury. If your phone starts bulging or separating, even slightly, or your laptop or tablet won’t sit flat, its battery is likely swelling. In this case, stop using the device immediately and contact its manufacturer for help. Second, watch out for heat. If the backside of your phone gets uncomfortably hot while it’s charging, that’s a warning sign, and once again time to contact the device manufacturer. More broadly, avoid placing devices in high-heat situations, especially when charging. The classic case is of a ride-share driver, with their windshield-mounted phone continuously charging while baking in direct sun, but it can also occur at home if your phone is charging on a sunny windowsill, above a radiator, or nestled into a blanket. The combination of an elevated charge situation and high ambient heat may increase the risk of a fire and is certain to degrade a battery’s health prematurely. More detail about heat and batteries can be found here.

Third, be especially careful with aftermarket batteries and chargers, even ones that carry a familiar brand name, because counterfeiting has become more and more common, and incentives to do so will only increase during a global emergency. This is a good reason to extend the life of your original batteries for as long as possible. While it can be annoying when smartphone manufacturers restrict users and unauthorized repair shops from doing battery replacements, it’s done in part because there’s ample evidence that fake replica batteries have a much higher risk of fire than authentic ones, and because the replacement process is often not straightforward. Likewise, cheap chargers can create overheating by delivering too much current, which can create a similar fire risk for your batteries.

Finally, extending the lifespan of our phones, laptops, tablets, and other daily-use devices will take on extra importance, especially with phone prices creeping into four digits. In my experience, preserving battery health is the single best way of doing this. I wrote some time ago about basic strategies; here are some updated recommendations to consider:

  • Avoid “fast-charge” approaches and use the lowest amount of charging current possible. Although it takes longer, charging your phone from a computer using a USB cable is much gentler on the internals of the battery. (Note that this principle also applies to electric vehicles – super-fast charging stations are hard on your vehicle battery.)
  • Avoid charging your phone overnight, because it’s better to not keep the battery at 100 percent charge for extended periods. I aim to keep my charge levels between 25 and 85 percent unless I’m traveling, and my year-old smartphone battery health has not degraded at all.
  • Per the previous point, Apple’s iOS operating system offers battery health monitoring, and in the newest version(13.0)  the option of “Optimized Battery Charging,” which learns your daily charging routine. This is worthwhile, and we’re starting to see other manufacturers and even mobile operators become more attuned to this type of functionality, particularly in Asia.

We all have plenty to worry about in these unusual times; hopefully these bits of advice will help prevent battery-related problems from adding to your load.