I am very interested and very confused with what an Accel battery eliminator is. Will it actually do away with my battery or does it just help bikes without batteries with electricity? It looks like a big capacitor to me.

 

Yup, big capacitor.

Used on some English bikes ( not factory) long, long ago.

It would hold just enough to get started ( usually a magneto system used for ignition anyway).

and the lights would dim at stops- like English electrics ( Lucas, Prince of Darkness) weren't bad enough.

The Lucas 3 Position Switch:
1.) Off
2.) Dim
3.) Flicker

Has no application in the modern world.

MK