Lithium-ion (Li-ion) batteries are popular in cell phones, laptops, cameras, tools, electric cars, bicycles, and even backup the power grid. You might be holding one right now. With so many in use, it’s good to know a few easy tips that can extend their life. Armed with this information, you can get more life from your electronics and may even prevent a fire.
Use Shorter Charge Cycles
Li-ion batteries degrade over time and have a limited number of charge/discharge cycles. You can extend this lifespan by using a shorter charge cycle. The results can be dramatic. If you cycle between 0% and 100% charge, you may expect less than 500 cycles. However, if you cycle between 20% and 80% you can extend the life up to 1500 cycles.
Consumer electronics manufacturers squeeze the most possible from small batteries. They charge to 100% and presume you will upgrade before the battery fails. As a result, most consumer devices don’t have a way to limit the maximum charge. You can still extend the lifespan of the battery by charging before they run below 20%.
In industrial use, such as electric cars, satellites, and large power grid backup systems, durability matters much more than the maximum charge level. These Li-ion packs are usually undercharged to extend their lifespan. Business-class Dell, Lenovo, and HP laptops also allow undercharging their batteries to please the corporate buyers who value lifespan and reduced repair costs. You can find more information and utilities below if you own one of these models.
Here’s an example screenshot from the Dell Power Manager utility.
As a rule, keep your battery above 20% charge if possible. Charge to less than 100% if your laptop has the ability.
Keep Them at Room Temperature
Both high and low temperatures are very stressful for Li-ion batteries. According to Battery University, a fully charged battery stored above 86°F is under more stress than a battery used for deep discharge/charge cycles. At 104°F, cycle capacity can drop by 40%. Extremely low temperature has similar effects. The optimum battery temperature is 68°F.
A laptop’s internal temperature can be well above 100°F even in a cold room. Make sure your laptop’s cooling vents aren’t blocked and use cooling or speed throttling utilities if available for your computer. Charging batteries while hot further degrades their lifespan.
Store Batteries Half-charged
If a battery needs to be stored, it’s best to store it at a 50% charge. Fully charged or deeply discharged batteries show much more damage from temperature changes.
Many devices offer fast chargers that
What’s the worst-case scenario?
One common scenario is charging a cell phone in a hot car. This combines some of the worst abuse for a Li-ion battery. Sometimes it’s not avoidable, but it can permanently shorten the life and capacity of your battery. Another common worst-cast is a GPS navigation system. These are often left on the vehicle dashboard full-time, plugged in and fully charged in the heat and direct sunlight. This can easily lead to swelling or worse.
Swelling is Dangerous.
Abusing a Li-ion battery with high heat, fast charging, and deep cycles can produce toxic internal gas, causing the battery to swell. Once this process has started, the battery is susceptible to thermal runaway. The internal heat triggers more gas, more swelling, and eventually a fire.
Unfortunately, even if you take all the proper precautions, some batteries will fail due to manufacturing defects. Keep an eye out for bulging. Many laptop models have the battery under the trackpad and you may notice it becomes stiff or lifted slightly. Cell phone can warp and crack. I’ve personally experienced bulging batteries three times. You may recall the Samsung Galaxy Note 7 was recalled and banned from all airlines because of a batch of bad batteries, and many laptops had issues back in 2006.
If you notice a bulging battery, don’t charge it. Don’t handle it or puncture it. Don’t throw it in the trash. The risk of a toxic fire is real. Take it to an authorized recycling center. You can find many on the Call2Recycle website here: https://www.call2recycle.org/locator/
- Keep batteries at room temperature.
- A half-charge is best for long-term storage.
- Avoid fast charging if possible.
- Short charge cycles (between 20% and 80%) can extend their life significantly.
- Watch for bulging batteries.
I’m often asked if it is safe to leave a laptop plugged in all the time. Yes, it’s safe. Modern devices have smart charging systems. In general, lithium-ion batteries are very safe and reliable. They are lightweight and have high energy storage. As a testament to their importance, this month a trio of scientists were awarded the Nobel Prize for their development of Lithium-ion batteries.
However, as amazing as they are, they do wear out over time. With a little care you can preserve their capacity for much longer.