You can't find a battery on Internet ? Tape battery for Archos 50 Dimond ! And you should find something... And if it doesn't work well ... I know change of telephone is horrible nobody likes it ! But you will have to 1 day... Good luck and good surching !!
I think will the re-construction you maybe didn't branch enverything or you just broken something ! It happens to everyone! Ask to Google or try to borow a battery to a volunteer and try to see if the battery is the problem ! Or try to un-make and re-make everything ! I hope I would have helped you !!