A battery for use in electronic devices and which is safely ingested into a body that exerts a pre-determined applied stress in a digestive tract of the body, the battery comprising: a cell top on an anode; a cell can on a cathode; a pressure-sensitive coating that comprises a quantum tunneling composite covering at least one of the cell top on the anode and the cell can on the cathode and providing pressure sensitive conductive properties including a compressive stress threshold such that, when a stress above the compressive stress threshold is applied to the quantum tunneling composite coating, the quantum tunneling composite coating is placed in a conductive state in which electrons are able to tunnel through the quantum tunneling composite coating; and a gasket that insulates and separates the cell top on the anode and the cell can on the cathode, wherein the compressive stress threshold is greater than the pre-determined applied stress associated with the digestive tract of the body, and wherein either: (i) the battery further comprises a waterproof seal extending between the pressure-sensitive coating and the gasket, thereby inhibiting the battery from short circuiting in a conductive fluid below the compressive stress threshold, or (ii) the pressure-sensitive coating is a water-impermeable coating extending to the gasket and fully covering the at least one of the cell top on the anode and the cell can on the cathode to leave no exposed surfaces. a cell top on an anode; a cell can on a cathode; a pressure-sensitive coating that comprises a quantum tunneling composite covering at least one of the cell top on the anode and the cell can on the cathode and providing pressure sensitive conductive properties including a compressive stress threshold such that, when a stress above the compressive stress threshold is applied to the quantum tunneling composite coating, the quantum tunneling composite coating is placed in a conductive state in which electrons are able to tunnel through the quantum tunneling composite coating; and a gasket that insulates and separates the cell top on the anode and the cell can on the cathode, wherein the compressive stress threshold is greater than the pre-determined applied stress associated with the digestive tract of the body, and wherein either: (i) the battery further comprises a waterproof seal extending between the pressure-sensitive coating and the gasket, thereby inhibiting the battery from short circuiting in a conductive fluid below the compressive stress threshold, or (ii) the pressure-sensitive coating is a water-impermeable coating extending to the gasket and fully covering the at least one of the cell top on the anode and the cell can on the cathode to leave no exposed surfaces. (i) the battery further comprises a waterproof seal extending between the pressure-sensitive coating and the gasket, thereby inhibiting the battery from short circuiting in a conductive fluid below the compressive stress threshold, or (ii) the pressure-sensitive coating is a water-impermeable coating extending to the gasket and fully covering the at least one of the cell top on the anode and the cell can on the cathode to leave no exposed surfaces.