I'm trying to figure out if I'm throwing money away here. My 2016 E350 sat for about five weeks while I was out of the country, and when I came back the battery was completely flat – not even enough power to pop the trunk. I hooked up a smart charger I borrowed from a friend and let it charge for about 24 hours. The charger said "full" but when I tried to start the car, it cranked slowly a couple times then went back to clicking. Does that mean the battery is damaged beyond repair? A mechanic told me that Mercedes batteries don't like being fully discharged and once they go below a certain voltage, the internal chemistry gets messed up and they'll never hold a full charge again. But another guy said I just need a more powerful charger to "desulfate" the battery. I'm confused. I've been searching for Mercedes Benz Battery Repair Dubai (https://batteryzoneuae.com/mercedes-battery-replacement/) and it seems like most places just replace rather than repair. Has anyone successfully brought a deeply discharged Mercedes battery back to life? Or am I just delaying the inevitable and should just buy a new one? Trying not to spend money I don't need to, but also don't want to get stranded somewhere.