Reducing shadowing losses in silicon solar cells using cellulose nanocrystal: polymer hybrid diffusers

Gridline shadowing is one of the main factors affecting the performance of silicon solar cells. In this demonstration, a straightforward, scalable approach is reported to reduce shadowing losses from metallic contacts on silicon solar cells by employing cellulose nanocrystals (CNC) mixed in a polymer- polydimethylsiloxane. The method is highly compatible with current solar cell module manufacturing. The CNC:polymer (CNP) hybrid diffusers, offering highly efficient broadband light diffusion, are applied atop the metallization areas to deflect the light impinging on metallic gridlines toward uncovered active areas on the solar cell. Simulations showed that the CNP diffuser is an excellent candidate for reducing shadowing losses within a wide range of incident angles, as it can reduce more than 30% of shadowing losses at normal incidence, and nearly 50% of the lost light can be recycled at the incident angle of 60°. Taking advantage of reduced shadowing losses, a new 6-busbar technology based on the CNP diffusers is proposed with lower manufacturing complexity and higher overall efficiency.