Systems and methods for providing an alert indicating battery removal from a wearable medical device

An externally worn cardiac monitoring and treatment system with battery detachment detection, the system comprising:

• a battery-powered externally worn cardiac device comprising
• a therapy electrode configured to deliver a therapeutic shock to a patient wearing the battery-powered externally worn cardiac device,
• a housing, and
• at least one processor disposed in the housing and being configured to process one or more ECG signals of the patient wearing the battery-powered externally worn cardiac device and determine at least one arrhythmia based on the one or more ECG signals, wherein the at least one arrhythmia is one or more of ventricular fibrillation, ventricular tachycardia, bradycardia, tachycardia, or asystole;
• and
• a rechargeable battery detachably disposed within the housing of the battery-powered externally worn cardiac device and removably coupled to the at least one processor, the rechargeable battery comprising
• at least one battery cell,
• detachment circuitry configured to
• detect whether the rechargeable battery is detached from the battery-powered externally worn cardiac device by monitoring a connection established between the rechargeable battery and the at least one processor, and
• output a battery status signal indicating that the rechargeable battery is detached from the battery-powered externally worn cardiac device, thereby rendering the system unable to deliver the therapeutic shock, and
• at least one of audible or vibrational alarm circuitry operably coupled to the detachment circuitry, the at least one audible or vibrational alarm circuitry configured to
• receive the battery status signal, and
• output at least one of an audible alert in a predetermined frequency range or a tactile alert if the rechargeable battery is detached.