Sustaining Efficiency at Elevated Power Densities with InGaAs Air Bridge Cells

TL;DR

This paper explores the performance of InGaAs airbridge cells under high power densities, developing a predictive model to optimize efficiency and thermal management for thermophotovoltaic applications.

Contribution

It introduces a device model based on experimental data that predicts InGaAs ABC performance at elevated power densities, guiding improvements and cooling strategies.

Findings

Achieves over 40% efficiency at 0.5 W/cm2 with high-quality material.

Demonstrates the model's utility in optimizing thermal management.

Identifies opportunities for performance enhancement at high power densities.

Abstract

Here we investigate the use of single-junction InGaAs airbridge cells (ABCs) at elevated power densities. Such conditions are relevant to many thermophotovoltaic (TPV) applications, ranging from space to on-demand renewable electricity, and require effective management of heat and charge carriers. Experimental characterization of an InGaAs ABC with varying emitter and cell temperature is used to develop a predictive device model where carrier lifetimes and series resistances are the sole fitting parameters. The utility of this model is demonstrated through its use in identifying near-term opportunities for improving performance at elevated power densities, and for designing a thermal management strategy that maximizes overall power output. This model shows that an InGaAs ABC with material quality that leads to the longest reported carrier lifetimes can attain efficiencies exceeding 40% at 0.5 W/cm2, even when considering the power necessary to cool the cells.