SWAPPABLE RECHARGEABLE BATTERY CARTRIDGE FOR HEARING AID AND CHARGER SYSTEM

Embodiments herein relate to ear-worn devices with swappable, rechargeable battery cartridges and charger cases for the ear-worn devices. In an embodiment, a hearing assistance system is included having a first ear-worn device can include a first cartridge having a rechargeable battery and a first cartridge charging structure, and a charger case can include a first case charging structure, where the first ear-worn device is configured to be positioned within the charger case so that the first cartridge charging structure of the first ear-worn device is adjacent to the first case charging structure within the charger case. The first cartridge is configured to be removed from the first ear-worn device and positioned within the charger case so that the first cartridge charging structure is adjacent to the first case charging structure within the charger case, without the ear-worn device being positioned in the charger case.