Nanostructured Super P Carbon Black for Lithium Storage: Understanding toward the Mechanism

Carbon-based materials have found widespread application in lithium-ion batteries (LIBs) as anode materials, conductive additives, and coating layers owing to their advantageous properties such as low (de)lithiation potential, high electrical conductivity, cost-effectiveness, and robust stability. Among these materials, nanostructured Super P carbon black stands out as a commonly utilized conductive additive in LIBs, yet its inherent lithium-ion (Li+) storage capabilities are frequently overlooked. In this study, we observe a significant capacity contribution and a continuous capacity increase from Super P during galvanostatic charge/discharge cycling. The capacity enhancement is accompanied by a structural transformation, where the initial quasi-layered structure of Super P evolves into a disordered porous structure due to repeated (de)lithiation cycles. Consequently, the Li+ storage mechanism undergoes a conversion from a sequential process involving surface adsorption, inner adsorption, and intercalation in pristine Super P to an inner adsorption-dominated mechanism in cycled Super P. Our findings provide insights into the phenomenon that some anode materials exhibit a continuous increase in capacity during charge/discharge cycling and could potentially guide the design of high-capacity nanostructured carbon-based anode materials for metal-ion batteries or supercapacitors.