Two astronauts from NASA have successfully completed the penultimate set of battery upgrades on the outside of ISS (International Space Station), moving forward a multi-year power system upgrade project for the ISS.
Bob Behnken and Chris Cassidy, the commander of Expedition 63 who launched the Crew Dragon rocket of SpaceX late in May, did their 2nd spacewalk on 1 July, just 5 days after starting the battery upgrade work for the orbiting laboratory.
The spacewalk started at 7.13am as Behnken and Cassidy swapped their spacesuits onto internal power.
The two astronauts, while working alongside one pallet supported by the robotic arm, Canadarm2 of the ISS, retrieved as well as installed a new lithium-ion battery & an adapter plate. They also removed the 6th and last, old nickel-hydrogen battery.
Every new battery measures around half the dimension of a standard refrigerator while the older nickel-hydrogen batteries weigh around 165 kilograms each. The lithium-ion battery replacements weigh around 194 kilograms.
Because the new installed batteries have higher capacity, a lithium-ion replacement can take the place of two old nickel-hydrogen batteries.
Notably, the astronauts, since January 2017, have been trying to upgrade every power channels of the ISS with 3 lithium-ion batteries, thus replacing the original 6 nickel-hydrogen batteries.