High-Rate NMC Cathodes Achieved with Carbon Nanotube Additive
Through a collaborative effort, the Dillon Group at NREL and the Whittingham Group at SUNY -Binghamton have enhanced the conductivity of NMC cathodes to improve their rate capability in Li-ion batteries. These layered cathodes usually suffer from poor electrical conductivity and capacity fade at high charge/discharge rates. To mitigate these problems, the researchers have incorporated single-wall carbon nanotubes (SWNTs) into the NMC cathodes (LiNi0.4Mn0.4Co0.2O2). The resultant composite cathodes exhibit stable high-rate capacities, ~130 mAh/g at 5C and nearly 120 mAh/g at 10C for over 500 cycles, which are significantly higher than those achieved with conventional NMC cathodes.