An electrochemical device, comprising: an electrode assembly comprising: an elongated positive electrode with a first longitudinal edge; an elongated negative electrode with a first longitudinal edge; and a separation layer having a first longitudinal edge and a second longitudinal edge; wherein the positive electrode, the separation layer, and the negative electrode are wound around a central axis thereby forming a coil of alternating electrode (12p, 12n) and separation layers such that the separation layer prevents direct contact between successive electrode layers (12p, 12n), the first longitudinal edge of the positive electrode extends beyond the first longitudinal edge of the separation layer, and the first longitudinal edge of the negative electrode extends beyond the second longitudinal edge of the separation layer; and a housing having a positive surface electrically coupled to the first longitudinal edge of the positive electrode and a negative surface electrically coupled to the first longitudinal edge of the negative electrode, said positive surface and said negative surface being parallel to each other; wherein, the electrode assembly is slightly wider than the distance between the parallel surfaces of the housing, the housing consists of a first telescoping half and a second telescoping half that are pressed together to enclose the electrode assembly such that a prescribed compressive load is applied to the electrode assembly by the housing. an electrode assembly comprising: an elongated positive electrode with a first longitudinal edge; an elongated negative electrode with a first longitudinal edge; and a separation layer having a first longitudinal edge and a second longitudinal edge; wherein the positive electrode, the separation layer, and the negative electrode are wound around a central axis thereby forming a coil of alternating electrode (12p, 12n) and separation layers such that the separation layer prevents direct contact between successive electrode layers (12p, 12n), the first longitudinal edge of the positive electrode extends beyond the first longitudinal edge of the separation layer, and the first longitudinal edge of the negative electrode extends beyond the second longitudinal edge of the separation layer; an elongated positive electrode with a first longitudinal edge; an elongated negative electrode with a first longitudinal edge; and a separation layer having a first longitudinal edge and a second longitudinal edge; wherein the positive electrode, the separation layer, and the negative electrode are wound around a central axis thereby forming a coil of alternating electrode (12p, 12n) and separation layers such that the separation layer prevents direct contact between successive electrode layers (12p, 12n), the first longitudinal edge of the positive electrode extends beyond the first longitudinal edge of the separation layer, and the first longitudinal edge of the negative electrode extends beyond the second longitudinal edge of the separation layer; and a housing having a positive surface electrically coupled to the first longitudinal edge of the positive electrode and a negative surface electrically coupled to the first longitudinal edge of the negative electrode, said positive surface and said negative surface being parallel to each other; wherein, the electrode assembly is slightly wider than the distance between the parallel surfaces of the housing, the housing consists of a first telescoping half and a second telescoping half that are pressed together to enclose the electrode assembly such that a prescribed compressive load is applied to the electrode assembly by the housing.