factory prototype battery and switch for Ossa TR280i
This photo shows the battery mounted behind the number plate or light if you have 2012 model.
The top connector is the head light so disregard that
The connector you will probably need to cut from the capacitor unless you can find a supplier for the plug - if you do find a supplier buy me some or tell me where to get them.
You can clearly see all the wiring, the battery replaces the capacitor in this configuration.
The red wire comming from the switch goes to earth, I have made a lead up to the kill switch and have connected the wire with the nut/bolt on the kill switch.
The only wiring modification you've had to make was to cut the connector from your factory capacitor.