Thermodynamic analysis of an efficient liquefaction unit with high-grade cold storage in liquid air energy storage systems

Abstract Liquid air energy storage (LAES) technology stands out as a promising large-scale energy storage solution owing to its inherent advantages such as high storage density, geographical flexibility, and scalability. The liquefaction unit, being a pivotal element of the LAES system, significantly influences its overall performance. However, existing research on the liquefaction unit within the LAES system remains incomplete. These technologies encounter challenges, including low efficiency, safety concerns, and substantial investment requirements, thereby impeding the widespread adoption of LAES in the energy storage market. In response to these challenges, this study proposes an efficient liquefaction unit tailored for high-grade cold storage in the LAES system. The suggested liquefaction unit utilizes a solid-phase medium for cold storage, demonstrating commendable cold storage performance. The study establishes relevant thermodynamic models and conducts a thorough thermodynamic analysis, exploring the impact of key design parameters on system performance. Results indicate that the innovative liquefaction unit effectively addresses current technological challenges, achieving a liquefaction rate exceeding 80% while ensuring safety and cost-effectiveness. This research contributes valuable insights to the LAES community and aims to drive the commercialization process of LAES technology.