A unique discontinuous cathode sheet structure is incorporated within thin-film electrochemical halfcells and full cells. A thin-film electrochemical cell structure includes a cathode sheet layer comprising a series of discontinuous cathode sheets. In a monoface configuration, each of the cathode sheets includes one cathode layer in contact with a current collector layer. In a biface configuration, each of the cathode sheets includes a pair of cathode layers each contacting a current collector layer. A gap is defined between adjacent ones of the cathode sheets. A solid electrolyte layer contacts a surface of one or both cathode layers, depending on the configuration, and extends across the gaps defined between the adjacent cathode sheets. The cathode sheets may be arranged in a number of rows to define a matrix of the cathode sheets.