1. A method for manufacturing a high-current printed circuit board, comprising:providing a circuit substrate comprising a substrate layer; a first circuit layer formed on the substrate layer; and a second circuit layer formed on the substrate layer and facing away from the first circuit layer, wherein first conductive circuits are defined on the first circuit layer, second conductive circuits are defined on the second circuit layer, and a line width of each of the first conductive circuits is greater than a line width of each of the second conductive circuits;
forming via holes in the circuit substrate, wherein the via holes pass through the first circuit layer, the substrate layer, and the second circuit layer; and
forming buffering circuits by infilling electrically conductive material into the via holes, wherein the buffering circuits are electrically connected the first circuit layer to the second circuit layer;
wherein a line width of each of the buffering circuits is greater than the line width of each of the second conductive circuits, thereby an electrical current from first conductive circuits and the buffering circuits to the second conductive circuits becomes a smaller current.