In one embodiment, a solid state actuator is provided having a solid state lithium storage material and a solid state volume changing material having a metal capable of changing volume in response to lithium insertion and removal. A solid state lithium ion transport material is located between the lithium storage material and the volume changing material. A pair of electrodes are connected so as to be capable of providing an actuation voltage across the lithium storage material and the volume changing material. In some embodiments, the volume changing material has active material particles comprised of metal contained in an inactive matrix. The active material particles may be aligned so that when the active material particles expand the volume changing material expands substantially in one direction. In some embodiments the volume changing material is a metal alloy and the lithium transport material is a high stiffness material. In some embodiments, multiple actuators are stacked, interleaved, or pillared.