How to store a laptop battery properly to save it from an early death

In the last two parts of this series, I covered the factors of temperature and charging. While the high temperatures inside modern laptops are probably the worst enemy of a Li-ion battery, frequent discharge/charge cycles will negatively influence a battery’s life. If your laptop is a desktop replacement, then you probably only need the battery every now and then. It can be quite frustrating if you want to use your laptop for the first time after a year without AC, only to realize that your batteries are already dead even though you never really used them. However, if you remove the battery from the laptop and store it accurately, there is a good chance that it will be in good condition when you need it next time.

Don’t store a battery that is almost empty. Stored batteries continue losing energy, albeit at a much slower pace. If the stored battery is totally discharged, it could be destroyed.

Don’t store a fully charged battery. Fully charged batteries deteriorate faster than half-charged batteries. Most articles I’ve read recommended storing laptop batteries with a 40–60% charge.

Store the battery at a low temperature. I usually put it in the fridge. It keeps my battery fresh and crisp. Check out this table at Wikipedia. 0°C (32°F) seems to be the best storage temperature. I wouldn’t put the battery in the freezer even though Li-ion batteries only freeze at approximately −40°C.

Store the battery in a dry place. A moist environment will accelerate discharging the battery.