As Boeing prepares to propose to the FAA a solution to the battery issue which has grounded the 787 fleet since mid-January, the company has issued a basic guide detailing the working of the battery and the aircraft’s electrical system, together with more background as to why lithium ion technology was selected in the first place.
In the backgrounder Boeing reiterates that since entering service 787 lithium-ion batteries, each with eight cells, “have logged more than 2.2 million cell-hours (updated 5.06 pm, 2/18)on the ground and in the air during more than 50,000 flight-hours. No battery-related incidents occurred before January 2013, when the airplane experienced two events. Investigation into these events is in progress.” Boeing adds it “has been using lithium batteries for decades safely and successfully in other demanding aerospace applications. For instance, they have been successfully used in the satellite industry.”
Commenting on its decision to select li-ion technology the manufacturer says it “designs airplanes with two key objectives in mind: design to prevent failures, and design in protections in case they do. Above all, the goal is to ensure that no single failure will ever prevent safe operation of the aircraft. This philosophy is integral to the battery design, which includes multiple independent protections to the battery.”
The backgrounder is available using this link: http://787updates.newairplane.com/787-Electrical-Systems/Batteries-and-Advanced-Airplanes