I have a problem starting my Freelander TD4 on frosty morning. Battery supplier has checked battery and shows no faults., mechanic has checked battery when on vehicle, shows no sign of battery drop. On frosty morning I try to start it and there's nothing apart from a clip, remove battery, put on...

My TD4 is using water on short journeys,theres scale around the cap (now replaced because I though it was blocked) still using it, no water in engine oil, not leaking out anywhere. Any ideas ?