Astronauts aboard the International Space Station (ISS) have completed the first of five spacewalks over the weekend which saw them replace nickel-hydrogen batteries on the space station’s truss with newer, more powerful lithium-ion batteries.
The newer battery was delivered just a week ago and astronauts Christina Koch and Andrew Morgan took a space walk to replace the old ones.
These new lithium-ion batteries are so powerful that only one is needed for every two old ones, which are original to the orbiting lab.
The batteries are charged through its solar panels and are essential to provide the station with constant life support as it is not in direct sunlight during the “eclipse” part of its orbit (35 minutes of every 90 minute orbit).
The nickel-hydrogen batteries have a design life of 6.5 years which means that they must be replaced multiple times during the expected 30-year life of the station. Since 2017, astronauts have been replacing them with lithium-ion technology, the type of rechargeable batteries found in most consumer gadgets.
The 180kg batteries are half the size of a refrigerator and these latest battery swaps are especially difficult given the extreme location on the station’s sprawling frame.
It is too far for the 17-metre robot arm to reach, forcing Koch and Morgan to lug the batteries back and forth themselves. This is why so many spacewalks are needed this time to replace the 12 old nickel-hydrogen batteries with the six new lithium-ion versions.
Nasa plans to wrap up the five battery spacewalks this month, followed by a Russian spacewalk.
Then five more US-Italian spacewalks will be conducted in November and December to fix a key science instrument.
Nasa is calling it a “spacewalk bonanza”.
This unusual run of spacewalks will feature the first all-female spacewalk – by Koch and Jessica Meir – later this month.
Koch is two-thirds of the way through a more than 300-day mission. It will be the longest single spaceflight by a woman.
The ISS is constantly being upgraded with new components. In April astronauts installed cables for powering its external robotic arm and improved the space station’s wireless communications coverage.