An electrically conductive adhesive layer is described. The adhesive layer includes an adhesive material and pluralities of electrically conductive at least first and second particles. The adhesive layer may have a thickness less than about 35 micrometers and an electrical resistance in the thickness direction of less than about 30 milliohms. A total volume of the pluralities of particles may be greater than 40% of a total volume of the adhesive layer. The first and second particles may have different shapes.