An energy storage device has all components, e.g. anode, electrolyte, and cathode contained and sealed with a trench in a substrate. Various methods and structures are disclosed for sealing the components. In some embodiments, a sealer or sealing layer seals the components. One embodiment uses a tension clamp to contain the components with additional pressure. Another embodiment uses a cathode structure cup which is held in place in the substrate via sidewall trench features. Different external connections to the device are disclosed. The invention enables full three-dimensional components to be created and contained entirely within the substrate during assembly, curing, galvanic cycling and other manufacturing processes and provides improved sealing of the components during device operation.