Improved electrochemical performance of Mn-based Li-rich cathode Li1.4Mn0.61Ni0.18Co0.18Al0.03O2.4 synthesized in oxygen atmosphere

Wan, Xia; Che, Wen; Zhang, Dongyun; Chang, Chengkang

doi:10.1016/j.jallcom.2021.159947

Cited by 9 publications

(5 citation statements)

References 66 publications

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“…Given the intended application of the obtained powders as cathode materials, the matrix of galvanostatic charge–discharge profiles at C/10 for all nine LNMFO powders are considered first in Figure . In agreement with the literature, ,,,− the first delithiation (first charge) profile of all LNMFO powders herein consists of an initial sloping region followed by a plateau, i.e., a nominally solid-solution delithiation region (monotonically increasing voltage versus state-of-charge) followed by a voltage-plateau region generally associated with activation of Li 2 MnO 3 and O 2 release. , The first delithiation capacities at each chelation ratio (CR) change as follows: CR = 1:1 (239, 250, 233 mAh·g –1 ), CR = 2:1 (282, 293, 300 mAh·g –1 ), and CR = 4:1 (248, 244, 231 mAh·g –1 ) as pH increases from 4.4 to 7.0 to 9.0. The average capacities of five lithiation cycles (steady-state capacity) after first delithiation at each CR are as follows: CR = 1:1 (127, 140, 131 mAh·g –1 ), CR = 2:1 (161, 185, 188 mAh·g –1 ), and CR = 4:1 (134, 140, 129 mAh·g –1 ).…”

Section: Resultssupporting

confidence: 85%

Impact of Synthesis Chelation on the Crystallography and Capacity of Li-Rich Li_1.2Ni_0.13Mn_0.54Fe_0.13O₂ Cathode Particles

Mishra

Taiwo

Yao

2023

ACS Appl. Mater. Interfaces

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The quest for removal of cobalt from battery materials has intensified in the face of intensifying demand for batteries. Cobalt-free lithium-rich Li 1.2 Ni 0.13 Mn 0.54 Fe 0.13 O 2 (LNMFO) is synthesized under variation of chelating agent ratio and pH using the sol−gel method. Systematic search of the chelation and pH space found that the extractable capacity of the synthesized LNMFO is most clearly correlated to the ratio of chelating agent to transition metal oxide; a ratio of transition metal to citric acid of 2:1 achieves greater capacity at the expense of relative capacity retention. Charge−discharge cycling, dQ/dV analysis, XRD, and Raman at different charging potentials are used to quantify the different degrees of activation of the Li 2 MnO 3 phase in the LNMFO powders synthesized under different chelation ratios. SEM and HRTEM analysis are employed to understand the effect of particle size and crystallography on the activation of Li 2 MnO 3 phase in the composite particles. An unprecedented use of the marching cube algorithm to evaluate atomic scale tortuosity of crystallographic planes in HRTEM revealed that subtle undulations in the planes in addition to stacking faults correlate to the extracted capacity and stability of the various LNMFO synthesized.

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Section: Resultssupporting

confidence: 85%

Impact of Synthesis Chelation on the Crystallography and Capacity of Li-Rich Li_1.2Ni_0.13Mn_0.54Fe_0.13O₂ Cathode Particles

Mishra

Taiwo

Yao

2023

ACS Appl. Mater. Interfaces

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“…44 The obvious peaks of (006)/ (012) and (018)/(110) have a good splitting, indicating that the sample has a well-ordered layered structure. 45 The Li + /Ni 2+ cation disorder degree in Co-free Li-rich cathode materials can be measured by the peak intensity ratio of I (003) /I (104) , it is indicated that the material has a low level of Li + and Ni 2+ disordering because the I (003) /I (104) ratio of 1.8561 is greater than 1.2. 46 Corresponding refinement parameters are summarized in Table I.…”

Section: Resultsmentioning

confidence: 99%

A Unique Formation Process on Rapidly Activating Oxygen Redox in Co-Free Li-Rich Layered Cathodes for Long-Cycle Batteries

Xiong,

Qiu,

Huang

et al. 2023

J. Electrochem. Soc.

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The utilization of oxygen redox in a Co-free Li-rich layered cathode usually needs to enhance the upper voltage to over 4.6 V, which results in structural changes and electrolyte requests. It is necessary to find a suitable formation method in full batteries that can quickly activate oxygen redox to balance the available capacity and optimal voltage. Here, a series of formation methods with two charge-discharge cycles under cut-off voltage 4.5-4.7 V are explored in practical pouch cells. A tiny voltage plateau appeared at 4.58 V was observed after the formation methods, which did not damage the material’s structure intensity in the first cycle. The surface of the cathode was found to form a thin film of spinel structure during the first charge-discharge process which would support the structure to endure a voltage higher than 4.58 V in the second charge-discharge and completely activate the capacity of Li-rich cathode. According to this guidance, a new formation method was adopted by controlling the cut-off voltage during the cycle process. The new strategy achieves a discharge-specific capacity of 214 mAh.g-1 and capacity retention of 99.0% after 500 cycles under 0.5C. This method shows great advantages in time cost, capacity retention, and Coulomb efficiency.

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“…In our previous work, a similar result was also observed. The LNCMA cathode material, synthesized in an oxygen atmosphere rather than in the air condition, exhibited an improved specific capacity (229.1 mAh g –1 ) and promoted coulombic efficiency (69%) when compared with the cathode synthesized in air . The promoted performance can also be attributed to the increased amount of R m solid solution phase after firing in the oxidation atmosphere.…”

Section: Introductionmentioning

confidence: 97%

Improved Electrochemical Performance of W⁶⁺-Doped Li-Rich Cathode Li_1.17Mn_0.51Ni_0.15Co_0.15Al_0.025O₂: Combined Results from the Reduced Residual Li₂MnO₃ Phase and Promoted Li Intercalation

Wan

Hang

Zhu

et al. 2021

ACS Sustainable Chem. Eng.

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Li-rich Mn-based cathode material suffers from severe capacity decay, voltage attenuation, and low initial coulombic efficiency, which hinder its commercialization in Li secondary batteries. In our previous work, Li1.17Mn0.51Ni0.15Co0.15Al0.025O2 (LNCMA-O) synthesized in an oxygen atmosphere presented an improved electrochemical performance due to the reduced amount of the unfavorable Li2MnO3 phase. In this work, 1 wt % W-doped Li1.17Mn0.5Ni0.15Co0.15Al0.025W0.01O2 (LNCMA-W) is synthesized to further facilitate the electrochemical performance. The W-doped cathode exhibits an excellent specific capacity of 247.3 mAh g–1 at 0.5C, with a further facilitated coulombic efficiency of 76.5% at the first cycle and an outstanding rate performance of 150.1 mAh g–1 at 5C. Such significant improvements can be attributed to the following points: (1) W6+ doping reduces the amount of residual Li2MnO3 C2/m phase in the cathode, thereby inhibiting the oxygen loss caused by Li2MnO3 activation and decreasing the irreversible capacity at the first cycle so that the initial coulombic efficiency of the material is improved. (2) The incorporation of W6+ increases the amount of LiMO2 R m solid solution, which can effectively increase the amount of reversible Li+ and improve the specific capacity of the material. (3) The stronger W–O bond can facilitate the stability of the crystal structure and suppress the volume change during the redox process, which further leads to an enhanced capacity retention. (4) The suppressed Li/Ni mixing and increased interplanar thickness of the Li layer after W6+ doping causes an improved diffusion coefficient of Li+, so that the rate performance of the cathode is significantly improved. In summary, a prospective approach for improving the electrochemical performance discovered in this work offers an instructive significance to Li-rich Mn-based cathode materials.

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Improved electrochemical performance of Mn-based Li-rich cathode Li1.4Mn0.61Ni0.18Co0.18Al0.03O2.4 synthesized in oxygen atmosphere

Cited by 9 publications

References 66 publications

Impact of Synthesis Chelation on the Crystallography and Capacity of Li-Rich Li_1.2Ni_0.13Mn_0.54Fe_0.13O₂ Cathode Particles

Impact of Synthesis Chelation on the Crystallography and Capacity of Li-Rich Li_1.2Ni_0.13Mn_0.54Fe_0.13O₂ Cathode Particles

A Unique Formation Process on Rapidly Activating Oxygen Redox in Co-Free Li-Rich Layered Cathodes for Long-Cycle Batteries

Improved Electrochemical Performance of W⁶⁺-Doped Li-Rich Cathode Li_1.17Mn_0.51Ni_0.15Co_0.15Al_0.025O₂: Combined Results from the Reduced Residual Li₂MnO₃ Phase and Promoted Li Intercalation

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Improved electrochemical performance of Mn-based Li-rich cathode Li1.4Mn0.61Ni0.18Co0.18Al0.03O2.4 synthesized in oxygen atmosphere

Cited by 9 publications

References 66 publications

Impact of Synthesis Chelation on the Crystallography and Capacity of Li-Rich Li1.2Ni0.13Mn0.54Fe0.13O2 Cathode Particles

Impact of Synthesis Chelation on the Crystallography and Capacity of Li-Rich Li1.2Ni0.13Mn0.54Fe0.13O2 Cathode Particles

A Unique Formation Process on Rapidly Activating Oxygen Redox in Co-Free Li-Rich Layered Cathodes for Long-Cycle Batteries

Improved Electrochemical Performance of W6+-Doped Li-Rich Cathode Li1.17Mn0.51Ni0.15Co0.15Al0.025O2: Combined Results from the Reduced Residual Li2MnO3 Phase and Promoted Li Intercalation

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Impact of Synthesis Chelation on the Crystallography and Capacity of Li-Rich Li_1.2Ni_0.13Mn_0.54Fe_0.13O₂ Cathode Particles

Impact of Synthesis Chelation on the Crystallography and Capacity of Li-Rich Li_1.2Ni_0.13Mn_0.54Fe_0.13O₂ Cathode Particles

Improved Electrochemical Performance of W⁶⁺-Doped Li-Rich Cathode Li_1.17Mn_0.51Ni_0.15Co_0.15Al_0.025O₂: Combined Results from the Reduced Residual Li₂MnO₃ Phase and Promoted Li Intercalation