There are pos & neg terminals under the bonnet - or indeed the 'hood' if you are in the yooknighted states.
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Hope that helps, with credit to the fella who took the original photograph, whomsoever he should be

Glen
Thanks - yes I am aware of those points. The issue is you can not access them with the bonnet closed. I can not open the bonnet without access to the inside of the car.
Also from looking into the bonnet latch that you unlock from inside of the car - it is actually a powered lock not mechanical with cable activated like a set of bike brakes - as with most cars - even my dads BMW uses a cable system - the RS uses 12v to activate which means even if I could get into the car - with a flat battery the bonnet would not release as no power...
The car is so poorly designed for handling a flat battery.
Issue now is - had rain for last few weeks so have not been able to get near the car - finally lifted the car up on jacks - no access to the bonnet release cable via the wheel arch as I had hoped...
so went hunting for B+ under the car. The starter motor B+ requires pulling half the car apart to access - with single use bolts that you have to replace every time they are removed. so instead I located the B+ on the alternator - REALLY hard to access with all the cables in the way.... really hard....
so put the car on charge... STUPID cars computer is interfering with the charge process.... as the battery was drained so much - due to rain and a few weeks of the STUPID car turning on the dash lights like a christmas tree display... has dropped the battery to a level that means If I can ever access it - I will most likely need to throw it away now... less than 8 months old.... but deep deep discharged
anyway charging with the hopes of getting just enough juice into the system to unlock the doors and boot.... but every time the car gets just enough juice- THE STUPID THING flashes the headlights and seems to be isolating the B+ from the alternator like there is some relay or switch that the ECU is controlling every time it wakes up - so I don't think I can charge from this point as between isolation.... the battery being so dead.... and the regular flashing of the headlights and tail lights it is discharging the battery as fast as I can charge it... SOME REALLY REALLY bad design by the germans here.
Also read that in some models if the car is stationary for more than 3 days it disables the mechanical door lock from being functional?? so most likely time the battery is going to go flat... leaving the door as the only access using the mechanical key - it will be disabled???
of for the simple days before cars had complex control systems like this
but if I could get in - then I could open the boot via the emergency release assuming I can lay the seats our of the way in this model.