Evaluating the Performance of Different Cathode Materials at Low Temperature for Lithium-ion Batteries

The cathode active materials play a key role in the performance of lithium-ion batteries. In the current research, three types of cathode materials (NMC, NCA, and LCO) proposed for use in lithium-ion batteries were evaluated and compared by electrochemical methods. The performance of these materials at subzero temperatures and high C-rates and also their cycle-ability were studied. Electrochemical impedance spectroscopy results were also used to conclude the results. It was found that NMC had the best and LCO showed the worst low-temperature performance. The ratio of discharge capacity at -30 ℃ to the discharge capacity at 25 ℃ for NMC, NCA, and LCO was 63.3%, 56.8%, and 15.2%, respectively. The rate capability evaluation also showed that NMC and NCA behaved close to each other at lower rates, and performed better than LCO. Furthermore, NMC separated itself from the other two materials at high rates and offered better rate capability. Cycle-ability results depicted the capacity retention of 99.2, 99.2, and 97.6% for NMC, NCA, and LCO, respectively