Thermal and mechanical properties of AlN/BN-filled PVDF composite for solar cell backsheet application

Heat dissipation is an important factor in maintaining solar cell module efficiency and in preventing thermal degradation of polymers within the cells. Aluminum nitride (AlN) and boron nitride (BN), surface-modified via a silane coupling agent, were used as a thermal conducting filler in conjunction with a poly(vinylidene fluoride) (PVDF) matrix with high thermal conductivity for the backsheet of the solar cell. The composites with 70 wt% and a 2:8 AlN/BN ratio showed a maximum thermal conductivity of 5.85 W m−1 K−1), which is 31 times larger than a pure PVDF matrix. The storage modulus was almost comparable to that of polyethylene terephthalate (PET), which is normally used to provide hardness for the PVDF. The water swelling ratio was reduced by addition of the filler, and the thermal and mechanical properties after swelling and drying were not degraded. The fabricated ceramic filler contained PVDF composite, satisfying the thermal and mechanical properties and long-term stability for a mono-layer structure for the backsheet of a solar cell.