Role of Al on the electrochemical performances of quaternary nickel-rich cathode LiNi0.8Co0.1Mn0.1−Al O2 (0 ≤ x ≤ 0.06) for lithium-ion batteries

The huge capacity loss during cycling is the main obstacle to the industrial application of nickel-rich cathode materials Li[Ni1−x−yCoxMny]O2 (NCM, 1 − x − y ≥ 0.8). However, at the same nickel content, another nickel rich Li[Ni1−x−yCoxAly]O2 (NCA, 1 − x − y ≥ 0.8) materials possess a much better cyclic performance due to the more powerful bond of Al-O compared with the NCM. But NCA yields a lower capacity caused by inactive Al. In this study, using the spray pyrolysis method to fabricate the new quaternary nickel-rich cathode material LiNi0.8Co0.1Mn0.1−xAlxO2 (NCMA, 0 ≤ x ≤ 0.06) is proposed to enhance the cyclic performance of NCM and with a limited capacity decrease for the incomplete substitution of Mn. The materials exhibit the evidently improvements in the electrochemical performance, among which the LiNi0.8Co0.1Mn0.06Al0.04O2 materials present the most excellent performances where the capacity retentions are up to 83.8% (3.0–4.4 V, 25 °C) after 200 cycles and 88.0% at 55 °C after 100 cycles. The satisfying results can be attributed to the inhibition of oxygen release and cationic disorder after the Al introduced, which are strongly confirmed by the results of structure refinement and first principles calculation.