p-type Bi0.5Sb1.5Te3 material were synthesised by mechanical alloying in ball-mill for 24 hours. We achieved best ZT of 0.65 at 500 K which is attributed to the extremely low thermal conductivity and high power factor. Contact resistance in the p-type thermoelement has been optimised by varying the combination of interfacial layer. Ni coated ptype thermoelement shows minimum change in the pellet resistance. Open circuit voltage of unicouple module fabricated using Ni coated thermoelement was measured. The maximum power output of 70.89 mW at hot end temperature of 200oC is achieved.