A biocompatible electronic device incorporating a point-of-use-activated microbattery, the biocompatible electronic device comprising: a housing; a sealed control electronics chamber formed within the housing; control electronics contained within the sealed control electronics chamber for controlling the operation of the biocompatible electronic device; a sealed electrode chamber formed within the housing; a plurality of electrodes contained within the sealed electrode chamber and connected to the control electronics; an access port formed within the housing for providing fluid access to the interior of the sealed electrode chamber; and a removable tab for selectively sealing the access port; such that, upon removal of the removable tab, a contacting fluid can contact the electrodes and act as an electrolyte for activating the microbattery, whereby to enable the microbattery to power the control electronics for the biocompatible electronic device.