Canon has marketed several different external power sources for a few of their high-end speedlites.  There are several other manufacturers of high-voltage power supplies that are compatible with Canon (Quantum, Jackrabbit, and more), but I ve never used them and are beyond the scope of this web page.

These power supplies provide 270 volts to a special HV port on these speedlites.  The normal AA-cells must be in the unit to provide power to the control circuitry, while the HV unit charges the flash tube (the 480EG uses only HV power).  Some flash recycle times, that I measured on a 550EX (full power flash recovery):

Compact Battery Pack-E This unit is very small, measuring 6.25" (15.8cm) x 2.75" (7cm) x .75" (2 cm).  It uses 6 AA cells, alkaline or NiCd.  Lithium cells cannot be used; NiMH cells are OK.  The coiled cord that plugs into the speedlite is not removeable.  I comes with a fabric case which can be attached to a belt.  It can be attached to the bottom of a camera through the tripod hole Compact Battery Pack-E2 This unit is same size and weight as the original Compact Battery Pack-E, and has the same accessories.  It uses 6 AA cells, alkaline, lithium, NiCd or Ni-MH.

Transistor Pack-E This unit is larger, measuring 8" (20cm) x 4" (10 cm) X 1.75" (4.3cm).  It uses 6 C cells, alkaline or NiCd.  Lithium cells cannot be used; NiMH cells are OK.  The "leather" case is integral to the unit and is provided with an adjustable strap.  The coiled cord which attaches to the speedlite is removeable. Transistor Pack-E NiCd This is the same unit as the Transistor Pack-E, but come with a self-contained rechargeable NiCd battery pack instead of a magazine that holds 6 C cells.

Battery Magazine TP

NiCd Pack TP

NiCd Charger TP