Patent ID: 8585647

Claim:
An ambulatory infusion device, the ambulatory infusion device being designed to be carried by a user external of a body, comprising: a battery receiving portion that receives a user-replaceable battery of variable individual characteristics, the user-replaceable battery serving as a primary power source of the ambulatory infusion device and being successively depleted during application; an electrically powered actuator of a dosing unit; an electronic controller that controls operation of the ambulatory infusion device; a testing unit that is operatively coupled to the electronic controller, the testing unit being designed to carry out a battery test, the battery test including determining an off-circuit voltage and an internal resistance of the user-replaceable battery; and an alerting unit that is operatively coupled to the testing unit and/or the electronic controller to provide an alert to a device user in dependence of a battery test result, wherein the ambulatory infusion device executes a power-up routine following insertion of the user-replaceable battery into the battery receiving portion, the power-up routine including carrying out the battery test to determine an initial internal resistance and an initial off-circuit voltage of the user-replaceable battery, and wherein the ambulatory infusion device stores a characteristic initial off-circuit voltage and a characteristic initial internal resistance for a number of different battery types and wherein the power-up routine includes assigning, based on a comparison of the characteristic initial off-circuit voltage and the characteristic initial internal resistance with the off-circuit voltage and initial resistance, a battery type to the user-replaceable battery.