Solar cell interconnection method using a flat metallic mesh
An improved method for interconnecting thin film solar cells to form solar cell modules is provided, the method comprising using a flat metallic mesh formed from a thin metallic strip to provide a current collection grid over a thin film solar cell. The method is particularly useful for forming interconnections between thin film solar cells deposited on flexible substrates. The rectangular cross sectional shape of the mesh elements provides an increased area of electrical contact to the solar cell compared to the small tangential area provided by elements of circular cross section. Mesh elements can be made higher rather than wider to improve conductivity without proportionally increasing shading loss. Various coatings can be applied to the mesh to improve its performance, provide corrosion resistance, and improve its cosmetic appearance.
1. A method for forming a solar cell module, comprising:
bringing a bottom surface of a thin flat metallic mesh from a first roll in contact with a top surface of a thin film solar cell from a second roll by passing the thin flat metallic mesh and the thin film solar cell through a set of rollers downstream from the first roll and second roll;
bending a tab region of the thin flat metallic mesh down and under an adjoining thin film solar cell; and
bonding a top surface of the tab region of the thin flat metallic mesh to a backside of the adjoining thin film solar cell thereby forming an electrical connection, wherein the thin flat metallic mesh includes wire-like elements joined in a circular, triangular, square, rectangular, trapezoidal, pentagonal, or hexagonal configuration.
2. The method of claim 1 , wherein the thin flat metallic mesh covers a substantial portion of the thin film solar cell.
3. The method of claim 1 , further comprising dividing the thin film solar cell having the thin flat metallic mesh into individual thin film solar cells.
4. The method of claim 3 , further comprising connecting the individual thin film solar cells in series to form a solar cell module.
5. The method of claim 1 , further comprising attaching the thin flat metallic mesh to the thin film solar cell with the aid of a conductive epoxy or a low melting point solder.