The recent grounding of all 50 of Boeing's (NYSE:BA) new 787 Dreamliner passenger jets has once again thrown the spotlight on lithium-ion batteries. One of the main reasons for the grounding was that a battery aboard a Dreamliner operated by All Nippon Airways overheated, forcing the plane to make an emergency landing in Japan.
An investigation by Japan's aviation authority has since cleared the battery as a possible source of the problem and has moved on to look into a system that monitors the battery's voltage, charging and temperature, according to the BBC. However, USA Today and other media outlets have also reported that All Nippon replaced the batteries in its new Dreamliners 10 times before the planes were grounded.
Moreover, lithium-ion batteries have faced concerns about overheating in the past. For example, in 2006, Dell (NASDAQ:DELL) recalled 4.1 million laptops after the batteries of some overheated or caught fire. Battery overheating problems were also reported for the iPhone 3GS, a previous version of the popular smartphone.
Lithium-ion batteries come in many types
Something that has gone largely unreported in these cases is that there are in fact many different types of batteries grouped together under the lithium-ion umbrella. For example, the battery's characteristics change dramatically depending on which metal is used for the cathode; the Dreamliner, for instance, uses a lithium-cobalt battery, but other products use different materials. The Chevy Volt, for example, is powered by a lithium-manganese battery.
Lithium-cobalt offers the highest power capacity of all lithium-ion battery types. That makes these batteries a popular choice for mobile devices, cameras and laptops, where small size and long battery life are crucial. However, they also carry the highest risk of overheating. Lithium-ion batteries that use other types of metal, such as manganese, iron and nickel, have less capacity than lithium-cobalt batteries, but greater stability.