Battery warning light

[TVR OWL]

My 2000 plate 450 Chim had been stood unused whilst the speedo was away for repair. After getting it back on the road it didn't seem to be running well : didnt pull like before and was a bit lumpy /spluttery at times. Yesterday I put new plugs in and used the leads and plug extenders off my Griff. Took it out for a run and seemed a bit better so was hopeful. However, 200m down the road glanced at dash and noticed battery warning light lit up ! so returned home
Any idea what the 6 month lay up could have damaged/ affected ? and why the battery warning lights now come on ?

Thanks.

[Goaty Bill]

It's a bit of a long shot, but check your 100 amp fuse.
The car will run badly when the battery is low, though usually when it's that low you can't start it.