During the six hour, 39 minute spacewalk, Hague and McClain replaced nickel-hydrogen batteries with newer, more powerful lithium-ion batteries for the power channel on one pair of the station's solar arrays, NASA said in a statement on Friday.
They also installed adapter plates and hooked up electrical connections for three of the six new lithium-ion batteries installed on the station's starboard truss.
These new batteries provide an improved power capacity for operations with a lighter mass and a smaller volume than the nickel-hydrogen batteries.
The batteries store power generated by the station's solar arrays to provide power to the station when the station is not in the sunlight, as it orbits the Earth during orbital night.
In addition, the astronaut duo also removed debris from outside of the station, securing a tieback for restraints on the Solar Array Blanket Box, NASA said.
McClain will again take a spacewalk on March 29 along with flight engineer Christina Koch to work on a second set of battery replacements on a different power channel in the same area of the ISS.
This would be the first-ever spacewalk with all-female spacewalkers, NASA said.
A third spacewalk on April 8 by Hague and David Saint-Jacques of the Canadian Space Agency will lay out jumper cables between the Unity module and the S0 truss, at the midpoint of the ISS's backbone.
This work will establish a redundant path of power to the Canadian-built robotic arm, known as Canadarm2. They will also install cables to provide for more expansive wireless communications coverage outside the orbital complex, as well as for enhanced hardwired computer network capability.
Space station crew members have until now conducted 214 spacewalks in support of assembly and maintenance of the orbiting laboratory.
Spacewalkers have now spent a total of 55 days, 21 hours and 39 minutes working outside the station.