Preventing harmful polarization of solar cells
View Patent ↗In one embodiment, harmful solar cell polarization is prevented or minimized by providing a conductive path that bleeds charge from a front side of a solar cell to the bulk of a wafer. The conductive path may include patterned holes in a dielectric passivation layer, a conductive anti-reflective coating, or layers of conductive material formed on the top or bottom surface of an anti-reflective coating, for example. Harmful solar cell polarization may also be prevented by biasing a region of a solar cell module on the front side of the solar cell.
1. A solar energy system comprising:
a series of solar cells in a solar cell module array, the series of solar cells having a first node and a second node opposite the first node, the first node being at a positive potential and connected to a positive output terminal of the solar cell module array and the second node being at a negative potential relative to the first node and connected to a negative output terminal of the solar cell module array, each solar cell in the series of solar cells having a front side facing the sun during normal operation and a backside opposite the front side;
a frame of a solar cell module in the solar cell module array, the frame being tied to ground; and
an inverter coupled to the positive output terminal and the negative output terminal, the inverter being configured to convert direct current generated by the solar cell module array to alternating current to be provided to a power grid, the inverter including an isolation circuit that provides isolation from the alternating current to be provided to the power grid,
wherein either the positive output terminal or the negative output terminal is tied to ground, the positive output terminal being tied to ground when solar cells in the series of solar cells have an N-type front side diffusion regions and the negative output terminal being tied to ground when solar cells in the series of solar cells have a P-type front side diffusion regions.
2. The solar energy system of claim 1 wherein the positive output terminal is tied to ground by way of a resistor.