Moisture content imaging in glass-glass and glass-backsheet photovoltaic mini-modules

We apply spectroscopic techniques to determine water concentration and kinetics in photovoltaic module packaging materials. Fourier Transform Infrared spectroscopy identifies moisture absorption bands for encapsulant and backsheet materials and determines the moisture uptake rate in a one cell minimodule. An infrared bandpass camera is used to image through the back side of the module down to the cell back metallization. Moisture ingress in double glass laminates is imaged for damp heat and typical field exposure conditions to show that water diffusion is independent of encapsulant degree of crosslinking.