Expedition 63 Commander Christopher Cassidy and Joint Operations Commander Robert Behnken, both NASA astronauts, completed the three and a half year process of upgrading the International Space Station\u2019s power systems during a spacewalk on July 21st.<\/p>\n
The spacewalk, designated US EVA-68, marked the 10th EVA for both astronauts, who have each accumulated over 50 hours of spacewalking time each during their respective careers. <\/p>\n
Upon exiting the Quest airlock, Cassidy and Behnken\u2019s EVA-68 marked the 12th and final in a series of spacewalks to replace all of the aging Nickel-Hydrogen (Ni-H2) batteries located on the outside of the ISS with newer Lithium-Ion batteries.<\/p>\n
The effort to replace the batteries began in January 2017 when Expedition 50 astronauts Shane Kimbrough and Peggy Whitson ventured outside to begin the labor-intensive process on the S4 Truss segment.<\/p>\n
In the three and a half years since, NASA and International astronauts have carried out nine more EVAs as part of the replacement efforts, fully replacing the older batteries on the S4, P4 and P6 truss segments and leaving just the S6 Truss remaining.<\/p>\n
Chris Cassidy, who launched aboard Soyuz MS-16 in April of this year, and Behnken, who launched the following month aboard SpaceX\u2019s Crew Dragon Demo-2 mission, had already completed two spacewalks focusing on the replacement of batteries on the S6 Truss element\u2019s 1B electrical channel before moving on to the 3B power channel \u2014 work that completed today.<\/p>\n
The first of those two spacewalks for the 1B power channel occurred on June 26th, with the second following on July 1st.<\/p>\n<\/p>\n