does anybody know the best place to buy a new car battery from ?

Sandia Stand near the (former)LeClerc store in Portimao are good value for money and have been offering a discount if you hand in an old battery. I used to use the nearby Stand Barata (near the BMW dealer) but I have found Sandia Stand to be cheaper and their products to be good quality.

I would use Firststop in Lagoa near the Fatacil, they have a a good range of car batterys at various prices, plus also give you something for your old one ( But Not alot).
Unfortunatley car batterys are another expensive item here in Portugal compared to some other countrys
Eg: Battery for VW Beetle 1.4 Convertable was 88.00€uros ( Firststops own brand, plus 2 year guarantee )

thank you for your assistance