Experimental characterization and aging analysis of commercial 18650 sodium-ion cells

Extensive use of lithium-ion batteries and scarcity of lithium are leading to re-emergence of sodium-ion batteries as a promising candidate, side-by-side with LIBs, to cover increasing demand of energy storage systems. Thus, development and commercialization of SIBs have been recently accelerated. Scientific research on first commercialized cells has been published regarding its fundamental parameters, aging and thermal performance. However, SIBs still require experimental study to continue developing and maturing their technology. For that reason, this work presents an electrical characterization and aging analysis of a commercial 1.3 Ah 18650 SIB. Based on experimental results obtained, this contribution reveals energy efficiencies of around 92% and an open circuit voltage with a plateau at a SOC of 35%. Regarding aging, samples full cycled at 0.5C exhibit a capacity loss of 15% after 310 cycles and stored cells age at a speed of 0.01 %/day.