Haven’t used the car for 2+ weeks. Got back off holiday and neighbour said they’d heard the alarm (Viper) going off in the garage but they saw no sign of attempted break in. After a few hours the alarm got weaker then went off.
Battery’s obviously flat so unlocked driver’s door with the key. I’d also left the bloody dashcam on which hadn’t helped

Can’t open the tailgate to get to the battery so need to charge it from under the bonnet. The +ve terminal is obviously under the red plastic cap. Is the -ve terminal the metal tube to the right about 6” long?
Ta