Lithium-manganese Batteries In EVs Much Safer Than Dreamliner Chemistry

Lithium-manganese Batteries in EVs Much Safer than Dreamliner Chemistry

Boeing's (NYSE:BA) Dreamliner battery woes are casting a dark shadow on the electric car industry's reliance on lithium batteries. The safety of lithium-based batteries has been routinely called into question by critics who believe the widespread adoption of the electric car is a Jetsonian fantasy whose time will never come.

Some of those critics have further railed against the use of lithium batteries in electric and hybrid vehicles using the revelation that lithium-cobalt oxide, the type of lithium cell chemistry used in the 787 Dreamliner, is also used in the Tesla Roadster and Model S automobiles. However, most electric car manufacturers have opted to use batteries based on lithium-manganese oxide, and to a lesser degree, lithium-nickel-manganese-cobalt oxide and lithium-iron-phosphate chemistries, as laboratory testing shows these are the safest in high-temperature applications. Lithium-manganese batteries may have lower energy density, but compared to lithium-cobalt batteries, they last longer and hold up better when damaged.

Six most common lithium battery types

The most common types of lithium-ion batteries include those mentioned above as well as lithium-nickel-cobalt-aluminum oxide and lithium titanate.

Lithium-cobalt oxide

Lithium-cobalt batteries consist of a cobalt-oxide cathode and a graphite-carbon anode. They are widely used in portable electronics such as laptops, cell phones and digital cameras due to their high specific energy capacity.

However, the lithium-cobalt combination has poor thermal stability. When damaged, overcharging or operating at temperatures over 130ºC, lithium-cobalt batteries are susceptible to thermal runaway — meaning an increase in temperature causes a reaction that further increases temperatures and eventually causes a fire; that is what experts believe occurred aboard two of Boeing's Dreamliners last month. The fleet of planes, heralded as the “the most electric ... ever to fly,” use 63-pound lithium-cobalt batteries as a backup power source for several systems.