Lithium Intercalation Cathode Materials for Lithium‐Ion Batteries

Low-Temperature Synthesis, Structural Characterization, and Electrochemistry of Ni-Rich Spinel-like LiNi2–yMnyO4 (0.4 ≤ y ≤ 1)

“…The current lithium-ion battery technology powers a wide range of modern devices (e.g., cell phones and laptops) and electric vehicles. − The state-of-the art cathodes include layered LiMO 2 (M = transition metal), spinel LiMn 2 O 4 , and olivine LiMPO 4 . − In particular, the spinel oxide is of great interest as the structure offers a 3D diffusion pathway for Li + ions and its small volume change during cycling. − Over the last two decades, however, the development of solid solutions with the normal spinel structure Li (tect.,8a) M 2(oct.,16d) ­O 4(tect.,32e) has been slow. For example, only LiMn 2– y Co y O 4 (0 ≤ y ≤ 1) and LiMn 2– y Ni y O 4 (0 ≤ y ≤ 0.5) have been reported for their structural analysis and electrochemistry in the Li-Mn-Ni-O and Li-Mn-Co-O systems. − A major reason is that LiM 2 O 4 (M = Ni, Mn, Co, and their solid solutions) phases with Ni oxidation state > 2+ and Co oxidation state > 3+ are difficult to stabilize by the conventional high-temperature synthesis processes.…”

Understanding the structure and structural degradation mechanisms in high-voltage, lithium-manganese–rich lithium-ion battery cathode oxides: A review of materials diagnostics

“…20 One problem with the sulfi de and chalcogenide cathode materials is low cell voltage (<2.5 V) due to the overlap of the higher-valent transition metal (TM): d band with the top of the nonmetal: p band. 21 Metallic Li anodes offer higher voltage, but their inherent safety problems and dendrite formation during cycling exclude them from practical use in LiBs. During the 1980s, Goodenough's group developed layered oxide cathodes, such as LiCoO 2 , which could provide a voltage of ∼ 4 V. 22 , 23 That innovation plus the introduction of intercalation compounds (graphite) by Dr. Rachid Yazami 24 as the anodes enabled Sony in 1990 to commercialize LiBs with LiCoO 2 cathodes and graphite anodes.…”

Femtosecond Laser Processing of Thick Film Cathodes and Its Impact on Lithium-Ion Diffusion Kinetics

“…The composite layer contains binder, conductive carbon, and active material rich in lithium cobalt oxide (LiCoO 2 ). The main drawbacks of LiCoO 2 cathodes, e.g., the high costs, the limited practical capacity due to structural and chemical instabilities at deep charge (x < 0.5 in Li x CoO 2 ), and the susceptibility to thermal runaway, are compensated by the addition of LiMn 2 O 4 , with lower costs and sufficiently high charge voltage [32]. The advantages of the new chemistries are a more balanced performance and an increased thermal stability of these cathode materials in comparison to that of the individual component.…”