The Wall Street Journal reports that Boeing will resume deliveries of its 787 Dreamliners following a multi-month grounding and subsequent overhaul of the aircraft's lithium ion batteries.

The jet was handed over to Japan's All Nippon Airways taking year-to-date deliveries to two as Boeing works reach its target of "more than 60" to airlines and lessors this year.

All Nippon, a unit of ANA Holdings Inc., was the 787's launch customer. The latest delivery increases its Dreamliner fleet to 18, and the airline expects to resume commercial flights with the jets on June 1.

The global grounding of the Dreamliners was prompted by an issue last January with overheating batteries. Regulators at the time ordered eight 787 operators "to halt flying the jet until a solution could be found to mitigate the lithium-ion battery's risk of smoke and fire." Deliveries from Boeing factories in WA, NC and SC were also on hold during this time

On April 19, Boeing announced FAA approval of their battery system improvements, "giving airlines the green-light to begin modifying their fleet of 787s," reports WSJ.

Notes Boeing:

The FAA's action will permit the return to service of 787s in the United States upon installation of the improvements. For 787s based and modified outside the United States, local regulatory authorities provide the final approval on return to service.

Approval of the improved 787 battery system was granted by the FAA after the agency conducted an extensive review of certification tests. 

The tests were designed to validate that individual components of the battery, as well as its integration with the charging system and a new enclosure, all performed as expected during normal operation and under failure conditions.

WSJ says Ethiopian Airlines was the first to restart commercial flight. Air India expects to be re-living the Dreamliner come Wednesday, and United Continental Holdings is looking to launch passengers on May 20.