Methods for forming pastes of powder particles coated with an electrically conductive coating are described. The powder particles, with or without an optional first conductive coating layer applied to their surface, are placed in contact with a cathode surface and immersed in an electroplating solution. An anode covered with a nonconducting but ion-permeable membrane is immersed in the solution in close proximity to the cathode. Agitation to move and gently tumble the powder over the cathode surface is provided. The powder particles are plated with a metal or metal alloy coating by biasing the anode with a positive voltage relative to the cathode. The coated powder is removed, rinsed and dried. The powder is added to a polymer material to form a paste which is heated to fuse the powder coating surfaces to form a network of interconnected particles and is further heated to cure the polymer. When the paste is disposed between adjacent electrically conductive surfaces, the coated particles fuse to the electrically conductive surfaces to form electrical interconnections.