Recent developments in control and integration of solid oxide fuel cells: From stack to system

Solid oxide fuel cells (SOFCs) offer broad application prospects owing to their diverse fuel sources, use of non-precious metal catalysts, high efficiency, and ability to generate high-grade waste heat. However, advanced coating techniques and highly active catalysts may lead to higher costs. Control and system integration technologies offer a viable means to balance performance and economic feasibility. This study presents a comprehensive review of recent developments in SOFC control optimization and integration applications over the past five years (2020–2025), focusing on three levels: the stack, power generation system, and integrated energy system. Advances in SOFC stack technologies, including model identification, fault diagnosis, and dynamic control, are summarized. Improvements in SOFC power generation systems are analyzed, including balance of plant (BOP), anode off-gas recirculation (AOGR), multi-stack structure, and energy buffer units. The development of novel integrated energy systems utilizing SOFC waste heat recovery and reuse is also discussed. In summary, this review explores how to enhance system performance through control optimization and integration strategies when SOFC stacks have already been manufactured. This helps researchers and practitioners quickly grasp recent advancements in SOFC stack control and system-level applications. Some advanced control strategies and integrated structures have been proved to improve the performance of SOFC stacks and systems, yet they remain unimplemented in commercial products. In addition, SOFC systems still face high construction costs and unverified long-term reliability. Despite the promising technical and environmental prospects of SOFC systems, the large-scale commercialization urgently requires extensive experimental validation and well-designed guiding policies.