Connection portion for connecting removable power unit to an electric device

An apparatus for connecting a removable power unit to an electric device, the removable power unit having an electrochemical cell, a power input/output module, and a casing, the casing housing the electrochemical cell and the power input/output module, the apparatus comprising:

• one or more electrical contacts configured to conductively couple with corresponding terminals of the electric device;
• an electrical connector configured to:
• conductively couple the one or more electrical contacts with the electrochemical cell and the power input/output module of the removable power unit, and
• provide a path for current flow from the removable power unit to the corresponding terminals of the electric device;
• and
• a body comprising:
• a keying feature;
• a housing configured to house the one or more electrical contacts and the electrical connector, wherein the body at least partially surrounds the electrical connector and the one or more electrical contacts, wherein the keying feature is configured to align with a complimentary keying feature on the removable power unit, and
• an attachment feature configured to removably secure the body to the electric device such that the one or more electrical contacts make electrical contact with the corresponding terminals of the electric device, wherein when the electrical contacts of the removable power unit are conductively coupled with the electric device, the electrical connector and the body are contained within a battery compartment of the electric device.