hello. i got this drill free with a sds corded i bought from screwfix a while back and as been handy as a second drill to keep a pilot drill in or some screwing. but its so weak in power ive stopped using it all together now. its not had a lot of use either. so my question is do you think the problem is the 1.3ah batterys wich die after about 20 screws??? is it worth thinking about upgrading to a higher ah battery or give the drill up?