An electrochemical cell (20, 120, 220, 320, 420) that comprises a single positive electrode, a single negative electrode, a separator that is disposed between the positive electrode and the negative electrode, wherein the positive electrode, the negative electrode and the separator are arranged in a stacked configuration, an electrically-insulating frame (60, 160, 260, 360, 460) disposed between portions of the positive electrode and the negative electrode so as to isolate the positive electrode and the negative electrode, the frame (60, 160, 260, 360, 460) having an inner peripheral edge that surrounds the separator and an outer peripheral edge, and a sealing material layer residing between the positive electrode and the negative electrode, the sealing material layer including a first sealing portion and a second sealing portion, the first sealing portion disposed between the frame (60, 160, 260, 360, 460) and an inward facing side of the positive electrode, and the second sealing portion disposed between the frame (60, 160, 260, 360, 460) and an inward facing side of the negative electrode, wherein the frame (60, 160, 260, 360, 460) is secured relative to the positive electrode and the negative electrode by the sealing material layer, characterized in that the outer peripheral edge of the frame (60, 160, 260, 360, 460) protrudes outward relative to a peripheral edge of the positive electrode and the negative electrode, and the inner peripheral edge of the frame (60, 160, 260, 360, 460) is sandwiched between the first sealing portion of the sealing material layer and the second sealing portion of the sealing material layer, whereby a seal exists between a positive electrode inward facing side of the positive electrode and the frame (60, 160, 260, 360, 460), and also between a negative electrode inward facing side of the negative electrode and the frame (60, 160, 260, 360, 460). a single positive electrode, a single negative electrode, a separator that is disposed between the positive electrode and the negative electrode, wherein the positive electrode, the negative electrode and the separator are arranged in a stacked configuration, an electrically-insulating frame (60, 160, 260, 360, 460) disposed between portions of the positive electrode and the negative electrode so as to isolate the positive electrode and the negative electrode, the frame (60, 160, 260, 360, 460) having an inner peripheral edge that surrounds the separator and an outer peripheral edge, and a sealing material layer residing between the positive electrode and the negative electrode, the sealing material layer including a first sealing portion and a second sealing portion, the first sealing portion disposed between the frame (60, 160, 260, 360, 460) and an inward facing side of the positive electrode, and the second sealing portion disposed between the frame (60, 160, 260, 360, 460) and an inward facing side of the negative electrode, wherein the frame (60, 160, 260, 360, 460) is secured relative to the positive electrode and the negative electrode by the sealing material layer, characterized in that the outer peripheral edge of the frame (60, 160, 260, 360, 460) protrudes outward relative to a peripheral edge of the positive electrode and the negative electrode, and the inner peripheral edge of the frame (60, 160, 260, 360, 460) is sandwiched between the first sealing portion of the sealing material layer and the second sealing portion of the sealing material layer, whereby a seal exists between a positive electrode inward facing side of the positive electrode and the frame (60, 160, 260, 360, 460), and also between a negative electrode inward facing side of the negative electrode and the frame (60, 160, 260, 360, 460).