Enhancing Lithium-Ion Battery Safety in Hybrid Energy Systems: The Role of Triphenyl Phosphate (TPP) in Electrode/Solvent Dynamics and Fire Mitigation

Lithium-ion batteries (LiBs) are key in sustainable energy solutions such as Power-to-X (P2X). Their high energy density, long cycle life, and declining costs have made them especially appealing for broader deployments (1). However, with these advantages come inherent risks, particularly those associated with thermal runaway and potential fire hazards (2-3). Recent advances and the push for higher energy densities have led to the introduction of new materials and chemistries within LiBs (4). But these modifications, while enhancing performance, can sometimes exacerbate the underlying risks, especially when exposed to real-world conditions like extreme temperatures or physical damage.<br/><br/>This research focuses on Triphenyl Phosphate (TPP) as a flame retardant to enhance LiBs safety in hybrid energy systems. TPP's potential in mitigating fire risks without significantly impacting battery performance is examined. The study utilizes density functional theory (DFT)-based molecular dynamics simulations to explore the interactions of TPP with lithium surfaces and the implications for the Solid Electrolyte Interphase (SEI) layer. We present three computational models to analyze TPP's influence on LiB safety at high temperatures, simulating scenarios with and without TPP. The results reveal TPP's potential in stabilizing thermal degradation products and reducing gas evolution during thermal stress. The study also investigates TPP's impact on the SEI layer's formation and structure, critical to LiBs performance and safety.<br/><br/>The findings suggest that TPP could serve as an effective additive in LiBs, particularly in complex, interconnected hybrid energy systems, offering a safer and more reliable energy storage solution. This research bridges knowledge gaps about TPP's role in LiBs and paves the way for designing safer batteries in the context of evolving energy storage demands.<br/><br/>References<br/>(1) D. Stampatori, P.P. Raimondi, M. Noussan, Li-Ion Batteries: A Review of a Key Technology for Transport Decarbonization, Energies, 13 (2020) 2638.<br/>(2) Q. Wang, P. Ping, X. Zhao, G. Chu, J. Sun, C. Chen, Thermal runaway caused fire and explosion of lithium ion battery, Journal of power sources, 208 (2012) 210-224.<br/>(3) C. Un, K. Aydin, Thermal runaway and fire suppression applications for different types of lithium ion batteries, Vehicles, 3 (2021) 480-497.<br/>(4) K. Chayambuka, G. Mulder, D.L. Danilov, P.H. Notten, From li-ion batteries toward Na-ion chemistries: challenges and opportunities, Advanced energy materials, 10 (2020) 2001310.