Back-up power supply with replaceable battery pack

A removable battery pack for docking with a fixed charger of the type having a charging circuit disposed on a circuit card and housed within a case, the circuit card of the type including a first portion having an oversized electronic component mounted thereto, and a second portion devoid of oversized electronic components, the battery pack comprising:

• (a) first and second batteries;
• and
• (b) a case housing the batteries with the second battery extending generally orthogonal to the first battery and with the first and second batteries occupying a volume generally adjacent the second portion of the circuit card, the first and second batteries defining an "L" shape and thereby defining a notch in the case for receiving the first portion of the circuit card.

A computer system comprising a back-up power supply electrically coupled thereto, the back-up power supply comprising:

• (a) a fixed charger mounted in the apparatus, the charger including a charging circuit electrically coupled to the computer system and an electromagnetic compatibility (EMC) shielded case housing the charging circuit;
• and
• (b) a removable battery pack docked with the charger through cooperative blind docking connections on the battery pack and the charger, the battery pack including first and second batteries electrically coupled to the charging circuit through the connections and a case housing the batteries to enclose the batteries and thereby substantially restrict external access to the batteries, wherein the charger shields the computer system when the battery pack is not docked to the charger.