Thermal stability of Li1-ΔM0.5Mn1.5O4 (M = Fe, Co, Ni) cathodes in different states of delithiation Δ

Bhaskar, Aiswarya; Gruner, W.; Mikhailova, Daria; Ehrenberg, Helmut

doi:10.1039/c3ra40356d

Cited by 6 publications

(7 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A second important limitation of our method is that we do not model mixed metal phases such as doped spinels 67 or mixedmetal layered compounds. 54 Our results pertain to mixed metal systems insofar as each metal acts independently of the other.…”

Section: Comparison Of Methods With Experiments and Limitationsmentioning

confidence: 99%

Relating voltage and thermal safety in Li-ion battery cathodes: a high-throughput computational study

Jain

Hautier

Ong

et al. 2015

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

High voltage and high thermal safety are desirable characteristics of cathode materials, but difficult to achieve simultaneously. This work uses high-throughput density functional theory computations to evaluate the link between voltage and safety (as estimated by thermodynamic O2 release temperatures) for over 1400 cathode materials. Our study indicates that a strong inverse relationship exists between voltage and safety: just over half the variance in O2 release temperature can be explained by voltage alone. We examine the effect of polyanion group, redox couple, and ratio of oxygen to counter-cation on both voltage and safety. As expected, our data demonstrates that polyanion groups improve safety when comparing compounds with similar voltages. However, a counterintuitive result of our study is that polyanion groups produce either no benefit or reduce safety when comparing compounds with the same redox couple. Using our data set, we tabulate voltages and oxidation potentials for over 105 combinations of redox couple/anion, which can be used towards the design and rationalization of new cathode materials. Overall, only a few compounds in our study, representing limited redox couple/polyanion combinations, exhibit both high voltage and high safety. We discuss these compounds in more detail as well as the opportunities for designing safe, high-voltage cathodes.

show abstract

Section: Comparison Of Methods With Experiments and Limitationsmentioning

confidence: 99%

Relating voltage and thermal safety in Li-ion battery cathodes: a high-throughput computational study

Jain

Hautier

Ong

et al. 2015

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

show abstract

“…They have observed discharge capacities >200 mAh g −1 when cycled in a wide potential window of 2.00-4.95 V. In addition, a capacity fading for the composition with x = 0 (pure LiNi 0.5 Mn 1.5 O 4 ) and an observed subsequent capacity increase with cycling is observed for the composites are reported. Lee et al [ 27 ] 4 (0 ≤ x ≤ 1) where they applied a hydroxide assisted coprecipitation synthesis route. A small amount of Co was added in the system to facilitate oxygen loss from the Li-rich layered structure.…”

Section: Introductionmentioning

confidence: 99%

Synthesis and Characterization of High‐Energy, High‐Power Spinel‐Layered Composite Cathode Materials for Lithium‐Ion Batteries

Bhaskar

Krueger²,

Siozios³

et al. 2014

Advanced Energy Materials

Self Cite

View full text Add to dashboard Cite

the LiNi 0.5 Mn 1.5 O 4 material is intensively investigated due to its high-voltage electrochemical activity, excellent rate capability as well as cycling stability. [2][3][4][5][6][7] LiNi 0.5 Mn 1.5 O 4 exists mainly in two crystallographic structures according to the oxygen stoichiometry in the material. [ 2,[8][9][10] The cation-ordered spinel (space group P 4 3 32) which is oxygen-stoichiometric, contains all the Mn ions in their tetravalent form. [ 11 ] At the same time in the cation-disordered structure (space group Fd 3 m) , in addition to the tetravalent Mn species, some of the Mn ions exist in the trivalent form as a result of oxygen deficiency from the crystal lattice. [ 12 ] This is mainly associated with the synthesis temperature. According to Pasero et al. [ 10 ] when the synthesis temperature exceeds ≈650 °C, the structure of LiNi 0.5 Mn 1.5 O 4 transforms gradually from the cationordered to cation-disordered. In the cation-ordered structure, the only electrochemically active species is Ni 2+ . The electrochemical reaction takes place at ≈4.7 V with two plateaus corresponding to Ni 2+ / Ni 3+ and Ni 3+ /Ni 4+ reactions, respectively. [ 2,12 ] Meanwhile, in the cation-disordered structure, a slight electrochemical activity is observed around 4.0 V versus Li/Li + as a result of Mn 3+ /Mn 4+ electrochemical reaction. [ 12 ] However, this material offers only a theoretical capacity of ≈148 mAh g −1 in the usual cycling voltage range 3.5-5.1 V. [ 13 ] It is possible to intercalate a second Li + into the material at voltage <3.0 V which in turn increases the capacity delivered. [ 1,14 ] For this purpose a Li excess electrode must be used as the counter electrode during cycling. Moreover, this process is believed to induce Jahn-Teller distortion of the structure due to the existence of excessive amount of Mn 3+ which in turn results in an average oxidation state of Mn less than +3.5. [ 1,14,15 ] The layered lithium-rich (Li-rich) materials with a general composition x Li 2 MnO 3 · (1 -x ) LiMO 2 (M = Mn, Co, Ni) are known to deliver capacities >250 mAh g −1 when cycled within the voltage range 2.0-4.8 V. [ 16 ] This material has a complex structure which is reported either as composites with nanodomains of Li 2 MnO 3 -and LiMO 2 -like features or as their solid solutions. [17][18][19][20] The powder diffraction patterns of this material

show abstract

“…Moreover, the material exhibits a lower thermal stability in comparison with other transition metal substituted spinels such as LiFe 0.5 Mn 1.5 O 4 and LiCo 0.5 Mn 1.5 O 4 . Therefore, the electrochemical performances and the thermal stabilities of LiNi 0.5 Mn 1.5 O 4 still have to be improved in order to fulfill the requirements for its applications 6…”

Section: Introductionmentioning

confidence: 99%

“…Partial substitution with Fe could also improve the thermal stability of the system as the spinel cathode materials containing Fe were found to have an increased onset temperature for thermal degradation 6. In addition, Fe substitution could increase the structural stability of the system during cycling and thereby improve the long‐term electrochemical performance.…”

Section: Introductionmentioning

confidence: 99%

Influence of Iron on the Structural Evolution of LiNi_0.4Fe_0.2Mn_1.4O₄ during Electrochemical Cycling Investigated by in situ Powder Diffraction and Spectroscopic Methods

Yavuz

Kiziltas-Yavuz

Bhaskar

et al. 2014

Zeitschrift anorg allge chemie

Self Cite

View full text Add to dashboard Cite

The cathode materials LiNi 0.5 Mn 1.5 O 4 and LiNi 0.4 Fe 0.2 Mn 1.4 O 4 were synthesized using a citric acid-assisted solgel method with a final calcination temperature of 1000°C. An impurity phase exists in LiNi 0.5 Mn 1.5 O 4 powders, which can be eliminated by substituting some of the Ni 2+ and Mn 4+ ions with Fe 3+ . The substitution of Fe into the spinel structure was confirmed by NMR and Mössbauer spectroscopy. The initial capacity of LiNi 0.4 Fe 0.2 Mn 1.4 O 4 powder synthesized at 1000°C (LNFMO) is slightly higher than that of LiNi 0.5 Mn 1.5 O 4 powder synthesized at 1000°C (LNMO). Addition-* M. Yavuz

show abstract

Thermal stability of Li1-ΔM0.5Mn1.5O4 (M = Fe, Co, Ni) cathodes in different states of delithiation Δ

Cited by 6 publications

References 15 publications

Relating voltage and thermal safety in Li-ion battery cathodes: a high-throughput computational study

Relating voltage and thermal safety in Li-ion battery cathodes: a high-throughput computational study

Synthesis and Characterization of High‐Energy, High‐Power Spinel‐Layered Composite Cathode Materials for Lithium‐Ion Batteries

Influence of Iron on the Structural Evolution of LiNi_0.4Fe_0.2Mn_1.4O₄ during Electrochemical Cycling Investigated by in situ Powder Diffraction and Spectroscopic Methods

Contact Info

Product

Resources

About

Thermal stability of Li1-ΔM0.5Mn1.5O4 (M = Fe, Co, Ni) cathodes in different states of delithiation Δ

Cited by 6 publications

References 15 publications

Relating voltage and thermal safety in Li-ion battery cathodes: a high-throughput computational study

Relating voltage and thermal safety in Li-ion battery cathodes: a high-throughput computational study

Synthesis and Characterization of High‐Energy, High‐Power Spinel‐Layered Composite Cathode Materials for Lithium‐Ion Batteries

Influence of Iron on the Structural Evolution of LiNi0.4Fe0.2Mn1.4O4 during Electrochemical Cycling Investigated by in situ Powder Diffraction and Spectroscopic Methods

Contact Info

Product

Resources

About

Influence of Iron on the Structural Evolution of LiNi_0.4Fe_0.2Mn_1.4O₄ during Electrochemical Cycling Investigated by in situ Powder Diffraction and Spectroscopic Methods