Charge–Discharge Properties of LiNi0.5Mn1.5O4 Cathodes Coated with Ta and P in Li-Ion Batteries (Supporting Information)

Li-ion batteries with LiNi0.5Mn1.5O4 cathodes offer high energy density; however, they face technical challenges due to side reactions related to metal dissolution and gas emissions caused by electrolyte decomposition, which hinder their practical applications. To address these issues, we introduced (Ta and P)-coating on LiNi0.5Mn1.5O4 particles using an aqueous solution containing Li, P, and Ta ions. Float gas evolution results demonstrated that the (Ta and P)-coating could effectively suppress gas generation on the LiNi0.5Mn1.5O4 cathode. Electrochemical impedance spectroscopic measurements before and after the float test revealed that the coating also mitigated increases in interfacial resistance, indicating the formation of a more stable interface between the coating layer and the electrolyte. Together, these effects enhance active material utilization and extend cycle life. Our study demonstrates the potential of Ta and P coatings to improve the high-temperature stability and long-term durability of LiNi0.5Mn1.5O4-based lithium-ion batteries.