Lithium Ion Batteries Remain a Point of Concern
Both Airbus and Boeing say the designs for their litium-ion systems are safe, in spite of known risk of flames, explosion, smoke and leakage.
Those are some pretty hefty “known” risks.
Now ANA says that prior to the fire, it had replaced batteries on its 787 aircraft some 10 times because of low charges.
Now the Kanto Aircraft Instrument Co whose system monitors voltage, charging and temperature of lithium-ion batteries is also under scrutiny, in addition to GS Yuasa who makes the batteries.
The National Transportation Safety Board is conducting a chemical analysis of internal short circuiting and thermal damage of the battery.
NTSB ISSUES SIXTH UPDATE ON JAL BOEING 787 BATTERY FIRE INVESTIGATION
January 29, 2013
WASHINGTON – The National Transportation Safety Board today released the sixth update on its investigation into the Jan. 7 fire aboard a Japan Airlines Boeing 787 at Logan International Airport in Boston.
The examination of the damaged battery continues. The work has transitioned from macroscopic to microscopic examinations and into chemical and elemental analysis of the areas of internal short circuiting and thermal damage.
Examination and testing of the exemplar battery from the JAL airplane has begun at the Carderock Division of the Naval Surface Warfare Center laboratories. Detailed examinations will be looking for signs of in-service damage and manufacturing defects. The test program will include mechanical and electrical tests to determine the performance of the battery, and to uncover signs of any degradation in expected performance.
As a party contributing to the investigation, Boeing is providing pertinent fleet information, which will help investigators understand the operating history of lithium-ion batteries on those airplanes.
An investigative group continued to interpret data from the two digital flight data recorders on the aircraft, and is examining recorded signals to determine if they might yield additional information about the performance of the battery and the operation of the charging system.
In addition to the activities in Washington, investigators are continuing their work in Seattle and Japan.