Benchmarking the Performance of Lithium and Sodium-Ion Batteries With Different Electrode and Electrolyte Materials

Abstract

Sodium-ion (Na-ion) batteries are considered a promising alternative to lithium-ion (Li-ion) batteries due to the abundant availability of sodium, which helps mitigate supply chain risks associated with Li-ion batteries. Many studies have focused on the design of Li-ion batteries, exploring their energy, power, and cost aspects. However, there is still a lack of similar research conducted on Na-ion batteries. A comparison of the cell voltage characteristics and rate capability of sodium and lithium-ion batteries using different types of electrodes and electrolytes. For sodium-ion batteries electrolytes used are NaPF₆ and NaClO₄ and electrodes used are NaCoO₂, NaNiO₂, NaFePO₄, (Na₃V₂(PO₄)₃), graphite, hard carbon, sodium metal, and sodium titanate. For lithium-ion batteries with LiPF₆ and KOH electrolytes and electrodes as LiCoO₂, NMC, LVP, Li₂MnSiO₄, graphite, silicon, lithium titanate (LTO), lithium metal. A thorough analysis of six important performance metrics is part of the investigation: Ragone plots, Electrolyte salt concentration versus spatial coordinate, electrolyte potential versus spatial coordinate, Cell voltage versus battery cell state of charge, Cell voltage versus time, and state variable versus time. Comparing operating voltage and rated capacity NMC and graphite is selected for lithium-ion batteries as this combination provides operating voltage up to 4.2 V and a rated capacity of 275 Wh/kg, for sodium-ion for NaCoO₂ and hard carbon which has an operating voltage of 2.5–3.8 V and rated capacity around 200 Wh/kg and another combination of electrode as NaFePO₄ and sodium metal with NaClO₄ electrolyte has a maximum operating voltage of 2.8–3.8 V and rated capacity around 200 Wh/kg. This paper shows significant influence of electrolyte selection on battery performance. The Ragone plots demonstrate that LiPF₆ electrolytes in lithium-ion batteries and NaPF₆ electrolytes in sodium-ion batteries both exhibit superior specific energy densities compared to their KOH and NaClO₄ counterparts, respectively. The work presented in this paper encourages researchers to select alternate electrolytes and electrodes for lithium-ion and sodium-ion batteries in order to obtain optimal device performance.