CP-E4 clone with external SLA battery

Looking inside my CP-E4 packs it is apparent that the 8 cells are in series which means they are providing 8x1.2 (NiMH) volts to the pack.

It would be relatively easy to put "terminal" connections into the CP-E4 and connect them to an external battery, but what voltage?

My Quantum Turbos are 6 volts with the appropriate circuitry for high voltage connection to the 580EX. The CP-E4 with 8 rechargeable batteries also has circuitry for higher voltage.

Has anyone tried this?

The Clones are relatively inexpensive and seem to be a reasonable source for the circuitry.

Thanks,
David

if you was using regular alkaline batteries at 1.5v that menas you have 12 volt so try using a 12v SLA with dumb batteries into the CP-E4 and have a "cheap" turbo