On the cycling stability of lithium-ion capacitors containing soft carbon as anodic material

• Soft carbons can be successfully used for the realization of high performance LICs.
• LIC containing soft carbon display high power and energy.
• LIC containing display stable performance for 50,000 cycles.

Petroleum coke (PeC), a soft carbon, displays excellent performance at high current densities so that it can be considered as a very promising material for high performance lithium-ion capacitors (LICs). PeC-based LICs deliver a specific energy and power of 48 Wh kg−1 and 9 kW kg−1, respectively, upon charge–discharge tests carried out using a current density of 4.5 A g−1 (corresponding to 30 C). These values are outperforming those displayed by supercapacitors and lithium-ion batteries under the same condition, and such performance can be maintained for 50,000 cycles.