Until now, the handicapped opening of my boot/trunk (lid falling down after opening) signalled me that the battery was going low. In time to hook up the charger .
Until now.
Luckily I leave the car unlocked in the garage.
After having her not used for quiet a while (and with not-so-new-batteries onboard) , the power has gone so low that even the interior light didn't come up....opening and the boot would'nt open.
Read up about booster-powering trough the starter and supplying power trough the cigar-lighter. Already ordered the Qtek cigar-lighter gizmo.
But realised then that I did not have tried to start the engine by the emergency-procedure (turning key in ignition to left and then to right).
To my surprised nothing happened at all. Dead as a Dodo ! Tried it a second time .... and the interior lights ànd the dash came up. Quickly pulled the boot-button and.......boot jumped open and up !! Serendipity .
Hooked up the charger that 'told' me the battery was completely flat. But I'm a happy camper now.
Wanted to share this method with you.

 

Brilliant, That tip may come in handy one day for a lot of people.