I think my battery is on the way out - on cold mornings, it turns the engine over very slowly to start with, and takes a number of turns before the engine finally starts. This has been the case for a few weeks, but the car has always started eventually. (Note it's not the glow plugs as I had them changed a couple of months ago.)
I never use the car for anything I couldn't use train, bus or bike for, so if one day it doesn't start at all then I'm happy to sort it out at my leisure. However, I don't wish to do any damage to other parts of the car - so my question is, is a battery of this description likely to be shortening the life of any other components?