Investigation on the microscopic features of layered oxide Li[Ni1/3Co1/3Mn1/3]O2 and their influences on the cathode properties

Properties of LiNi1/3Co1/3Mn1/3O2 cathode material synthesized by a modified Pechini method for high-power lithium-ion batteries

“…The initial open circuit voltages of the freshly assembled cells were around 3.1 and 3.2 V. On applying the current, the cell voltage rapidly increased to about 3.7 V and then gradually increased until it reached the upper voltage limit of 4.5 V for all the samples. This charge/discharge behavior of Pechini LiNi 1/3 Co 1/3 Mn 1/3 O 2 agrees well with the literature reports by other groups [22,23]. It can be seen that the charge/discharge behavior of the LiNi 1/3 Co 1/3 Mn 1/3 O 2 is different with that of the layered LiCoO 2 which has well-defined plateau at about 3.9 V indicating a first order phase transition [24].…”

“…The extraction of Li from the tetrahedral sites requires very high potential (>4.6 V). If the same mechanism applies to LiNi 1/3 Co 1/3 Mn 1/3 O 2 , the increased content of Li in the TM layer in the low temperature synthesized samples will lower the charge capacity with an upper limit of 4.5 V. The samples synthesized at 900 and 1000 • C show large charge/discharge capacities of 203/180 and 210/181 mAh/g, respectively, which agrees well with literature report on wellcrystallized LiNi 1/3 Co 1/3 Mn 1/3 O 2 with about 4% Li/Ni intermixing [22,23]. The irreversible capacity for the first cycle decreases as the synthesis temperature increases from 700 to 900 • C, then increases as the synthesis temperature goes up to 1000 • C. There are several factors affecting the irreversible capacity of this electrode material.…”

A Generalized SOC-OCV Model for Lithium-Ion Batteries and the SOC Estimation for LNMCO Battery

“…When it is charged to above 4.5 V, all lithium ions deintercalated from the bulk of the material, along with the oxidation from Ni 2+ to Ni 4+ and from Co 3+ to Co 4+ . The layered LNMCO structure is thus damaged, attributed to the degraded electrochemical performance caused by the high charging voltage [24,25]. Consequently, the layered LNMCO cathode with homogenous phase reactions only works over the range of 0 ≤ x ≤ 2/3 in Li 1 In theory, the dQ/dV plot of the LNMCO electrode should therefore show two isolated peaks near these voltage plateaus.…”

High-energy cathode materials for Li-ion batteries: A review of recent developments

“…Different routes have been used to synthesize layered NCM oxides, such as co-precipitation [42][43][44], sol-gel [45], solid-state reaction [30,46], combustion [47], molten salt [48], hydrothermal method [49], spray pyrolysis [50] and so on. Shin et al [51] synthesized Li[Ni 1/3 Co 1/3 Mn 1/3 ]O 2 by solid-state (SP), combustion (CP) and co-precipitation (PP) methods. The oxide obtained by PP showed the smallest primary particles and least cation mixing, leading to the first discharge capacity of 198 mAh g −1 in the voltage range of 2.5-4.6 V at a current density of 40 mA g −1 .…”