Abstract: Provided herein are electrochemical cells that include a metal sheet adjacent to a solid-state Li ion-conducting electrolyte in a manner that isolates a Li metal negative electrode from exposure to either, or both, a liquid electrolyte or a gel electrolyte used as a catholyte in the positive electrode. Some of the electrochemical cells include a series of electrochemical stacks, which may be stacked in a variety of configurations including configurations that share a Li metal negative electrode.