Thermal stability of triple-junction gallium arsenide cells

Laser wireless power transmission (LWPT) systems have significant applications in the field of wireless energy transmission, including spacecraft sensor networks, satellite-tosatellite communication, and remote power supply. However, continuous laser exposure increases the temperature of the photovoltaic (PV) cells in the LWPT system, thus decreasing the electrical output performance. This work, which we believe is a new approach, is on the basis of a notch film designed by a combined merit function proposed to maintain the electrical output performance while under 1064-nm continuous laser irradiation. Moreover, the thermal stability of PV cells under laser irradiation was investigated, which revealed the recoverability of the open-circuit voltage (Voc) of the cells at different temperatures, and the thermal damage to cells was a gradual process. This process began with the vaporization of the encapsulation adhesive, followed by a decline in, but still recoverable and functional, electrical performance, and finally, the cell was completely damaged. The thermal stability of the PV cells coated with the notch film increased ten-fold compared to those without it. Furthermore, the correlation between the minimum Voc and maximum temperature of the cells with notch films of different performances was established. These investigations serve as references for further optimization of LWPT.