Limp mode throwing a bunch of codes

[andym3]

Hi guys,

My 2010 e92 m3 just went on limp mode. Engine malfunction, increased emissions on dash board. The exhaust smoke smell is extremely strong. I read the codes and found 9 faults…
277B fuel cap signal
278D alternator missing
2B36 DME: Misfire with cutoff cyl 2
2B37 DME: Misfire with cutoff cyl 3
2B38 DME: Misfire with cutoff cyl 4
2B39 DME: Misfire with cutoff cyl 5
2B41 DME: Misfire with cutoff several cyl
2B44 DME: Misfire impairing exhaust emission cyl 3

Background: 86000 miles. Recently replaced rod bearings, new fuel breather valve, new fuel tank cap, new fuel leak detection pump. I have always been having battery problems on and off, having to use a charger to charge the battery. But I don’t drive the car a lot, so I thought it was normal. But now I suspect is the alternator. I am having trouble starting the car now. I checked the battery is at 12.5V, so it should be good. What do you guys think?