Yes, she can be used as an Electro battery if she is equipped with the Emblem of Severed Fate Artifact set. Further, she can be used alongside characters such as Raiden Shogun, Yae Miko, and Fischl to help gather more energy particles. I believe that Kuki Shinobu can be used with Yae Miko as a battery because Yae Miko has a very high Elemental Burst energy need.