An unmanned Japanese space capsule is heading to the International Space Station with 5,500 kilograms (12,000 pounds) of cargo including food, experiments and new batteries.

The craft was launched Sunday at 2:52 a.m. from the Tanegashima Space Center in southern Japan. It will take four and a half days to reach the space station.

The launch was delayed for about two weeks because of bad weather and a mechanical problem.

An H-2B rocket carrying the Kounotori 7 cargo spacecraft lifts off from Tanegashima Space Center in the southwestern Japan prefecture of Kagoshima, early Sunday, Sept. 23, 2018. The unmanned Japanese space capsule is heading to the International Space Station with 5,500 kilograms (12,000 pounds) of cargo including food, experiments and new batteries. (Kyodo News via AP)

An H-2B rocket carrying the Kounotori 7 cargo spacecraft lifts off from Tanegashima Space Center in the southwestern Japan prefecture of Kagoshima, early Sunday, Sept. 23, 2018. The unmanned Japanese space capsule is heading to the International Space Station with 5,500 kilograms (12,000 pounds) of cargo including food, experiments and new batteries. (Kyodo News via AP)

The delay has led NASA to postpone two space walks to install the six lithium-ion batteries until new crew members arrive next month. They will replace aging nickel-hydrogen batteries for the station's electric power.

The capsule is a 9-meter- (30-foot-) long cylinder that will be retrieved by the space station's robotic arm. It is named Kounotori, which means white stork.