The Federal Aviation Administration officially approved a new lithium on Thursday --
The ion battery system of the Boeing 787 Dream series.
The ruling ended three.
Ban on the month and clear the airline to fly the plane with passengers again.
The FAA's "airworthiness directive" is technically only applicable to United Airlines, the only one with a new high so fartech jet.
But it will set the standards that regulators in Japan, Europe and elsewhere will follow.
Other American Airlines that order 787 will eventually accept the new rules.
The FAA has set the cost of repairing six United Airlines jets at around $2. 8m (£1. 8m).
This approval marks a turbulent period for Boeing and its airline customers from two lithium-
On January, in different events less than two weeks apart, ion batteries overheated on two Dreamliners.
The two aircraft are owned by Air Japan and air all, and so far they have nearly half of 50 Dreamliners.
The flight ban effectively prevented the delivery of new aircraft to customers.
Boeing spent thousands of hours developing fixes, even before investigators determined what caused the battery to overheat, smoke, and fire in an accident.
The investigation, led by the National Transportation Safety Commission, continues, and the Commission held a hearing on the issue this week.
Last week, the FAA allowed Boeing to start installing new battery systems on the plane.
On Wednesday, the company said it expects to resume delivery early next month and complete the renovation of 50 customer aircraft by mid-termMay.