Renault Clio II - Stop & battery light flickering on - peckythepirate

Whilst driving my clio at night the stop light and battery light flickers on and off, its sometimes that quick that if you blink you miss it. its also doing it during the day but not so noticable. I have taken off all the earth to body & body to engine cables and cleaned them thoroughly. also ther area that they bolt to as well as the battery terminals. therefore I am now confused as to what is causing the lights to flicker.