A portable battery pack comprising: a wearable pouch and one or more batteries enclosed in the wearable pouch; wherein the one or more batteries include: a battery element; a battery cover including one or more channels to accommodate wires of one or more flexible omnidirectional leads, a compartment sized to receive the battery element, and a top hat style rim around a perimeter of the battery cover; a battery back plate attached to the top hat style rim of the battery cover; and the one or more flexible omnidirectional leads including a connector portion which extends away from the battery cover and a wiring portion, wherein a flexible spring is provided around the wiring portion, wherein the wiring portion and the flexible spring are held securely in the one or more channels in the battery cover via a clamping mechanism such that a portion of the flexible spring is positioned inside the battery cover and a portion of the flexible spring is positioned outside the battery cover; wherein the wearable pouch includes: a closeable opening through which the one or more batteries are operable to be removed from the wearable pouch; and one or more openings through which the one or more flexible omnidirectional leads from the one or more batteries can be accessed. a wearable pouch and one or more batteries enclosed in the wearable pouch; wherein the one or more batteries include: a battery element; a battery cover including one or more channels to accommodate wires of one or more flexible omnidirectional leads, a compartment sized to receive the battery element, and a top hat style rim around a perimeter of the battery cover; a battery back plate attached to the top hat style rim of the battery cover; and the one or more flexible omnidirectional leads including a connector portion which extends away from the battery cover and a wiring portion, wherein a flexible spring is provided around the wiring portion, wherein the wiring portion and the flexible spring are held securely in the one or more channels in the battery cover via a clamping mechanism such that a portion of the flexible spring is positioned inside the battery cover and a portion of the flexible spring is positioned outside the battery cover; a battery element; a battery cover including one or more channels to accommodate wires of one or more flexible omnidirectional leads, a compartment sized to receive the battery element, and a top hat style rim around a perimeter of the battery cover; a battery back plate attached to the top hat style rim of the battery cover; and the one or more flexible omnidirectional leads including a connector portion which extends away from the battery cover and a wiring portion, wherein a flexible spring is provided around the wiring portion, wherein the wiring portion and the flexible spring are held securely in the one or more channels in the battery cover via a clamping mechanism such that a portion of the flexible spring is positioned inside the battery cover and a portion of the flexible spring is positioned outside the battery cover; wherein the wearable pouch includes: a closeable opening through which the one or more batteries are operable to be removed from the wearable pouch; and one or more openings through which the one or more flexible omnidirectional leads from the one or more batteries can be accessed. a closeable opening through which the one or more batteries are operable to be removed from the wearable pouch; and one or more openings through which the one or more flexible omnidirectional leads from the one or more batteries can be accessed.