This is not the first time I've heard of 'dodgy' brand new batteries, I was unfortunate to have 2 on the trot, each holding its charge for a maximum of 2 weeks only. I went through the car with a fine toothed comb. checking earth leads, all connections and couldn't figure it out so sent it back asking for a replacement. Another new one was duly sent only for the same to happen again. This time I took it to an Auto Electrical specialist to check over and lo and behold it was another useless battery. I sent this one back supported by the Auto Electrical Engineers report and the company was happy to send me yet another one which i'm glad to say third time lucky it worked like a charm.