Synthesis and electrochemical performances of LiNi0.5Mn1.5O4 spinels with different surface orientations for lithium-ion batteries

Jung

ACS Appl. Mater. Interfaces

et al. 2021

Nickel-rich lithium metal oxide cathode materials have recently be en highlighted as next-generation cathodes for lithium-ion batteries. Nevertheless, their relatively high surface reactivity must be controlled, as fading of the cycling retention occurs rapidly in the cells. This paper proposes functionalized nickel-rich lithium metal oxide cathode materials by a multipurpose nanosized inorganic materialtitanium silicon oxidevia a simple thermal treatment process. We examined the topologies of the nano-titanium silicate-functionalized nickel-rich lithium metal oxide cathodes with scanning electron microscopy and quantitatively analyzed their improved mechanical properties using microindentation. The cell containing nickel-rich lithium metal oxide cathodes suffered from poor cycling behavior as the electrolytes persistently decomposed; however, this behavior was effectively inhibited in the cell by nano-titanium silicate-functionalized nickel-rich lithium metal oxide cathodes. Further ex situ analyses indicated that the particle hardness of the nano-titanium silicate-functionalized nickel-rich lithium metal oxide cathode materials was maintained, and decomposition of the electrolyte by the dissolution of transition metals was thoroughly inhibited even after 100 cycles. Based on these results, we concluded that the use of nano-titanium silicate as a coating material for nickel-rich lithium metal oxide cathode materials is an effective way to enhance the cycling performance of lithium-ion batteries.

Section: Resultsmentioning

confidence: 94%

Interface-Stabilized Layered Lithium Ni-Rich Oxide Cathode via Surface Functionalization with Titanium Silicate

Jung

ACS Appl. Mater. Interfaces

et al. 2021

“…Irregularly shaped samples synthesized in 20% LiCl at 750 and 850 °C and plate-like samples synthesized with 100% LiCl at 850 °C representing either end of the LiCl composition spectrum gave the poorest rate performances. The increased impurity phases, large size, and larger extent of cation disorder explain the overall low capacity and the significant loss of capacity at faster C rates …”

Section: Resultsmentioning

confidence: 99%

“…The increased impurity phases, large size, and larger extent of cation disorder explain the overall low capacity and the significant loss of capacity at faster C rates. 51 In LNMO, Mn 3+ is expected to be redox-active and can lead to better electrochemical performance and rate capability than the perfectly stoichiometric material. More Mn 3+ was expected to improve the rate capability due to the increased lattice parameter, improving Li + diffusion; 52 however, the accompanying rock-salt Li x Ni 1−x O-type impurities that also occur with increased synthesis temperatures and an increase in cation disorder may have been detrimental to performance.…”

Section: Influence Of Molten Salt Composition Andmentioning

confidence: 99%

Tuning the Morphology and Electronic Properties of Single-Crystal LiNi_0.5Mn_1.5O_4−δ: Exploring the Influence of LiCl–KCl Molten Salt Flux Composition and Synthesis Temperature

Spence

Sainio

et al. 2020

Inorg. Chem.

Single-crystal materials have played a unique role in the development of high-performance cathode materials for Li batteries due to their favorable chemomechanical stability. The molten salt synthesis method has become one of the most prominent techniques used to synthesize single-crystal layered and spinel materials. In this work, the molten salt synthesis method is used as a technique to tune both the morphology and Mn3+ content of high-voltage LiNi0.5Mn1.5O4 (LNMO) cathodes. The resulting materials are thoroughly characterized by a suite of analytical techniques, including synchrotron X-ray core-level spectroscopy, which are sensitive to the material properties on multiple length scales. The multidimensional characterization allows us to build a materials library according to the molten salt phase diagram as well as to establish the relationship among synthesis, material properties, and battery performance. The results of this work show that the Mn3+ content is primarily dependent on the synthesis temperature and increases as the temperature is increased. The particle morphology is mostly dependent on the composition of the molten salt flux, which can be tailored to obtain well-defined octahedrons enclosed by (111) facets, plates with predominant (112̅) facets, irregularly shaped particles, or mixtures of these. The electrochemical measurements indicate that the Mn3+ content has a larger contribution to the battery performance of LNMO than do morphological characteristics and that a significant amount of Mn3+ could become detrimental to the battery performance. However, with similar Mn3+ contents, morphology still plays a role in influencing the battery cycle life and rate performance. The insights of molten salt synthesis parameters on the formation of LNMO, with deconvolution of the roles of Mn3+ and morphology, are crucial to continuing studies in the rational design of LNMO cathode materials for high-energy Li batteries.

“…Combining the above results, the Li 3 InCl 6 solid‐state electrolytes can be applied to a high‐voltage cathode, and it also gets good cycling performance. The LNMO cathode voltage is 4.7 V, but the maximum voltage of Li 3 InCl 6 is 4.2 V, there will be interface problems between Li 3 InCl 6 and LNMO [71,72] . It will cause a side reaction during charging and discharging.…”

Section: Solid Electrolytes Developments For Higher Energy Density Ba...mentioning

confidence: 99%

Controlling Cell Components to Design High‐Voltage All‐Solid‐State Lithium‐Ion Batteries

et al. 2023

All‐solid‐state batteries with solid ionic conductors packed between solid electrode films can release the dead space between them, enabling a greater number of cells to stack, generating higher voltage to the pack. This Review is focused on using high‐voltage cathode materials, in which the redox peak of the components is extended beyond 4.7 V. Li−Ni−Mn−O systems are currently under investigation for use as the cathode in high‐voltage cells. Solid electrolytes compatible with the cathode, including halide‐ and sulfide‐based electrolytes, are also reviewed. Discussion extends to the compatibility between electrodes and electrolytes at such extended potentials. Moreover, control over the thickness of the anode is essential to reduce solid‐electrolyte interphase formation and growth of dendrites. The Review discusses routes toward optimization of the cell components to minimize electrode‐electrolyte impedance and facilitate ion transportation during the battery cycle.