Proper Storing of Lithium Batteries

Lithium ion batteries, whether of conventional or lithium polymer ("lipo") design, provide reliable power for laptops, cell phones and a host of other electronic devices. Proper storage of lithium ion batteries is essential when you are not going to be using them. Storing these batteries incorrectly can damage them and will certainly shorten their useful lives.

Storage Basics

• Lithium ion batteries are sensitive to extremes of temperature, especially heat. When you are not using the battery it should be stored in a cool place. The storage area should also be dry and not in a bathroom or other area that tends to be damp. If you don't have a suitable location, lithium ion batteries can be placed in a sealed container and kept in a refrigerator (not a freezer). Avoid storing the batteries in areas that will be heated by sunlight or other heat sources. Finally, never place a lithium ion battery on a metal or other conductive surface. This will greatly increase the rate of self-discharge, draining the battery.

Long-Term Storage

• If a lithium ion battery won't be used for a prolonged period (weeks or longer) it should be properly prepared for storage. Charge the battery to only 40 percent capacity. This keeps long-term capacity reduction to a minimum with limited self-discharge. You should recharge the battery to 40 percent every two or three months.

Intermittent Use

• Laptops and some other devices will automatically charge a lithium ion battery to capacity. While this is convenient, it also shortens battery life. A fully charged laptop battery will have an internal temperature of about 110 to 115 degrees F (45 degrees C), well above recommended storage temperatures of 60 degrees or less. To maximize battery life, run the laptop or other device on the battery until it is at about 40 percent capacity and then remove it. When you are ready to use the device on battery power again, reinstall the battery a few hours ahead of time so it can be brought to full charge.