UC San Diego

Energy generation and storage technologies must improve to address the growing energy concerns, mitigate the effects of climate change, and pave the way for emerging high-power technologies. Degradation mechanisms in silicon solar modules limit operational lifetimes and increase the levelized cost of energy of photovoltaic (PV) systems. Recent studies have linked potential-induced-degradation and sodium migration through the module stack as the main degradation mechanism. However, quantifying the rate of the sodium migration through the material layers is challenging because of the presence of electronic traps within the SiNx antireflection coating. Through the development of a trap-corrected bias-temperature stress method, the sodium migration kinetics through the SiNx layer are determined in this dissertation, making possible to model and extend solar module lifetimes. Regarding energy storage, emerging technologies such as 5G, Internet of Things, and wearable electronics require safe and flexible batteries that can withstand high currents densities. While traditional Li-Ion batteries (LIBs) offer excellent energy densities, their safety and power requirements fall short. In contrast, aqueous Zn batteries offer a safe and benign chemistry and outperform LIBs at high current densities thanks to their higher electrolyte ionic mobilities. The second part of this dissertation focuses on the development of high performance flexible and printable Zn-AgO batteries for high-power electronics. Furthermore, to extend the cycle and shelf life of these devices, a deep dive investigation of the degradation mechanisms is performed using in-situ¬ X-ray Microscale Computed Tomography. Combined with detailed electrochemistry, the effects of material corrosion and parasitic reactions are quantified and visualized in 3D tomograms. From these results, the material system is optimized to extend the battery shelf life and perform >300 cycles at a high areal capacity 12.5 mAh/cm2. In summary, this dissertation focuses on the investigation of key degradation mechanisms in PV and battery systems and the optimization to improve device lifetimes.