When it comes to the volatile new lithium-ion battery technology, Boeing and Airbus are heading in different directions.

Faced with the potential of a lengthy investigation into what caused batteries on two Boeing 787 jets to catch fire or emit smoke last month, Airbus said Friday that it had dropped plans to use the technology on its forthcoming wide-body jet, the A350-XWB, to avoid possible delays in producing the planes. But Boeing, which has much more at stake, said later in the day that it would stick with the batteries and that it is working with regulators on how to reduce the risks even if the cause of the hazards is not clearly found.