Patent US 9,263,189

An apparatus for storing electrical energy comprising at least: a first multilayer section; a second multilayer section disposed above the first multilayer section; and a spacer layer disposed between the first and second multilayer sections and comprising a dielectric material, wherein each of the first and second multilayer sections comprising a pinned magnetic layer having a fixed magnetization direction, a free magnetic layer having a reversible magnetization direction, and an isolative layer disposed between the pinned and free magnetic layers, the pinned and free magnetic layers are substantially anti-ferromagnetically exchange coupled to each other through the isolative layer; and wherein the pinned magnetic layers of the first and second multilayer sections are electrically coupled in parallel with each other, and the free magnetic layers of the first and second multilayer sections are electrically coupled in parallel with each other.