Two-terminal device

A two-terminal device, including a substrate comprising:

• a first cell having a first characteristic resistance, wherein the first cell comprises at least one first groove having a first face and a second face;
• a second cell, spaced apart from the first cell along a web direction of the substrate, having a second characteristic resistance, wherein the second cell comprises at least one second groove having a first face and a second face;
• wherein the at least one first groove and the at least one second groove are each coated with a first material on the respective first faces and coated with a second material on the respective second faces;
• wherein the at least one first groove and the at least one second groove are each at least partially filled with a third material;
• a first terminal and a second terminal, each terminal being formed towards or at opposing edges of the substrate across a transverse direction, and each terminal being in electrical communication with the first cell and the second cell;
• and
• a connecting portion, between the first cell and the second cell, the connecting portion providing electrical connectivity between the first cell and the second cell, and having a third characteristic resistance;
• wherein the third characteristic resistance is greater than both the first characteristic resistance and the second characteristic resistance, such that an electrical charge from the first or second cell is extractable at the first terminal or the second terminal in preference to transferring between the first cell and the second cell across the connecting portion
• wherein the connecting portion comprises:
• a plurality of channels, each channel comprising the first material on one side of the channel and the second material on the other side of the channel, wherein the plurality of channels each have a respective channel resistance that, in combination, form the third characteristic resistance;
• and
• wherein the plurality of channels comprises a first channel that is at least partially filled with the third material such that an electrical connection is made between the first material and the second material.