Included are embodiments of an ambulatory infusion device. Some embodiments include a battery receiving portion that receives a user-replaceable battery of variable individual characteristics. The user-replaceable battery may serve as a primary power source of the ambulatory infusion device and being successively depleted during application. Similarly, some embodiments include a dosing unit with an electrically powered actuator and an electronic controller that controls operation of the ambulatory infusion device. Still some embodiments include 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. Still some embodiments include 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.
