Description:
<jats:sec><jats:label /><jats:p>Solar cell in combination with a secondary battery is a straightforward power supply solution for portable electronics. When used indoors or outdoors under sufficient illumination conditions the combination is attractive to realize self‐sustained devices or extend off‐grid operation time. However, only little fraction of widely spread portable devices worldwide are equipped with PV energy harvesters. Besides low‐average power, combination of discrete PV module and battery is bulky for extreme demands in modern portable electronics. Integration of thin‐film solar cell with a thin‐film storage cell in a monolithic, customizable module is a viable option. The low level cell‐to‐cell integration is possible with thin‐film silicon multi‐junction solar cells providing sufficient voltage to charge Li‐ion storage cell. In this work, we focus on the development of triple‐junction thin‐film silicon solar cells for monolithic integration with lithium ion storage cells. We show that with appropriate voltage matching a triple junction thin‐film silicon solar cell provides efficient charging for lab‐scale Li‐ion storage cell under a range of illumination intensities. Maximum solar energy‐to‐battery charging efficiency of 8.8% was obtained.</jats:p></jats:sec>