In technologically important LiNi1−x−yMnxCoyO2 cathode materials, surface reconstruction from a layered to a rock-salt structure is commonly observed under a variety of operating conditions, particularly in Ni-rich compositions. This phenomenon contributes to poor high-voltage cycling performance, impeding attempts to improve the energy density by widening the potential window at which these electrodes operate. Here, using advanced nano-tomography and transmission electron microscopy techniques, we show that hierarchically structured LiNi0.4Mn0.4Co0.2O2 spherical particles, made by a simple spray pyrolysis method, exhibit local elemental segregation such that surfaces are Ni-poor and Mn-rich. The tailored surfaces result in superior resistance to surface reconstruction compared with those of conventional LiNi0.4Mn0.4Co0.2O2, as shown by soft X-ray absorption spectroscopy experiments. The improved high-voltage cycling behaviour exhibited by cells containing these cathodes demonstrates the importance of controlling LiNi1−x−yMnxCoyO2 surface chemistry for successful development of high-energy lithium ion batteries.
Subscribe to Journal
Get full journal access for 1 year
only $5.17 per issue
All prices are NET prices.
VAT will be added later in the checkout.
Rent or Buy article
Get time limited or full article access on ReadCube.
All prices are NET prices.
Whittingham, M. S. Lithium batteries and cathode materials. Chem. Rev. 104, 4271–4302 (2004).
Whittingham, M. S. Ultimate limits to intercalation reactions for lithium batteries. Chem. Rev. 114, 11414–11443 (2014).
Doeff, M. M. Batteries: Overview of Battery Cathodes 709–739 (Springer Encyclopedia of Sustainability Science and Technology Springer Science + Business Media, LLC, 2012).
Xu, X., Lee, S., Jeong, S., Kim, Y. & Cho, J. Recent progress on nanostructured 4V cathode materials for Li-ion batteries for mobile electronics. Mater. Today 16, 487–495 (December, 2013).
Hwang, B. J., Tsai, Y. W., Carlier, D. & Ceder, G. A combined computational/experimental study on LiNi1∕3Co1∕3Mn1∕3O2 . Chem. Mater. 15, 3676–3682 (2003).
Islam, M. S. & Fisher, C. A. J. Lithium and sodium battery cathode materials: Computational insights into voltage, diffusion and nanostructural properties. Chem. Soc. Rev. 43, 185–204 (2014).
Jung, S.-K. et al. Understanding the degradation mechanisms of LiNi0.5Co0.2Mn0.3O2 cathode material in lithium ion batteries. Adv. Energy Mater. 4, 1300787–1300794 (2013).
Xu, B., Fell, C. R., Chi, M. & Meng, Y. S. Identifying surface structural changes in layered Li-excess nickel manganese oxides in high voltage lithium ion batteries: A joint experimental and theoretical study. Energy Environ. Sci. 4, 2223–2233 (2011).
Hwang, S. et al. Investigation of changes in the surface structure of LixNi0.8Co0.15Al0.05O2 cathode materials induced by the initial charge. Chem. Mater. 26, 1084–1092 (2014).
Lin, F. et al. Influence of synthesis conditions on the surface passivation and electrochemical behavior of layered cathode materials. J. Mater. Chem. A 2, 19833–19840 (2014).
Lin, F. et al. Surface reconstruction and chemical evolution of stoichiometric layered cathode materials for lithium-ion batteries. Nature Commun. 5, 3529 (2014).
Lin, F. et al. Profiling the nanoscale gradient in stoichiometric layered cathode particles for lithium-ion batteries. Energy Environ. Sci. 7, 3077–3085 (2014).
Yang, F. et al. Nanoscale morphological and chemical changes of high voltage lithium-manganese rich NMC composite cathodes with cycling. Nano Lett. 14, 4334–4341 (2014).
Abraham, D. P. et al. Microscopy and spectroscopy of lithium nickel oxide-based particles used in high power lithium-ion cells. J. Electrochem. Soc. 150, A1450–A1456 (2003).
Zheng, J. et al. Corrosion/fragmentation of layered composite cathode and related capacity/voltage fading during cycling process. Nano Lett. 13, 3824–3830 (2013).
Lin, M. et al. Insight into the atomic structure of high-voltage spinel LiNi0.5Mn1.5O4 cathode material in the first cycle. Chem. Mater. 27, 292–303 (2015).
Qiao, R. et al. Direct evidence of gradient Mn(II) evolution at charged states in LiNi0.5Mn1.5O4 electrodes with capacity fading. J. Power Sources 273, 1120–1126 (2015).
Jarry, A. et al. The formation mechanism of fluorescent metal complexes at the Li(x)Ni(0.5)Mn(1.5)O(4−δ)/carbonate ester electrolyte interface. J. Am. Chem. Soc. 137, 3533–3539 (2015).
Markus, I. M., Lin, F., Kam, K. C., Asta, M. & Doeff, M. M. Computational and experimental investigation of Ti substitution in Li1 (NixMnxCo1−2x−yTiy)O2 for lithium ion batteries. J. Phys. Chem. Lett. 5, 3649–3655 (2014).
Kam, K. C. & Doeff, M. M. Aliovalent titanium substitution in layered mixed Li Ni–Mn–Co oxides for lithium battery applications. J. Mater. Chem. 21, 9991–9993 (2011).
Kam, K. C., Mehta, A., Heron, J. T. & Doeff, M. M. Electrochemical and physical properties of Ti-substituted layered nickel manganese cobalt oxide (NMC) cathode materials. J. Electrochem. Soc. 159, A1383–A1392 (2012).
Maier, J. Nanoionics: Ion transport and electrochemical storage in confined systems. Nature Mater. 4, 805–815 (2005).
Nie, A. et al. Twin boundary-assisted lithium ion transport. Nano Lett. 15, 610–615 (2015).
Cheng, L. et al. The origin of high electrolyte–electrode interfacial resistances in lithium cells containing garnet type solid electrolytes. Phys. Chem. Chem. Phys. 16, 18294–18300 (2014).
Cheng, L. et al. Effect of surface microstructure on electrochemical performance of garnet solid electrolytes. ACS Appl. Mater. Interfaces 7, 2073–2081 (2015).
Belharouak, I., Lu, W., Vissers, D. & Amine, K. Safety characteristics of Li(Ni0.8Co0.15Al0.05)O2 and Li(Ni1∕3Co1∕3Mn1∕3)O2 . Electrochem. Commun. 8, 329–335 (2006).
Sun, Y.-K. et al. High-energy cathode material for long-life and safe lithium batteries. Nature Mater. 8, 320–324 (2009).
Sun, Y.-K. et al. Nanostructured high-energy cathode materials for advanced lithium batteries. Nature Mater. 11, 942–947 (2012).
Cho, Y., Oh, P. & Cho, J. A new type of protective surface layer for high-capacity Ni-based cathode materials: Nanoscaled surface pillaring layer. Nano Lett. 13, 1145–1152 (2013).
Jung, D. S., Ko, Y. N., Kang, Y. C. & Park, S. B. Recent progress in electrode materials produced by spray pyrolysis for next-generation lithium ion batteries. Adv. Powder Technol. 25, 18–31 (2014).
Zhang, X. & Axelbaum, R. L. Spray pyrolysis synthesis of mesoporous lithium–nickel–manganese-oxides for high energy Li-ion batteries. J. Electrochem. Soc. 159, A834–A842 (2012).
Jung, D. S. et al. Hierarchical porous carbon by ultrasonic spray pyrolysis yields stable cycling in lithium–sulfur battery. Nano Lett. 14, 4418–4425 (2014).
Bang, J. H., Didenko, Y. T., Helmich, R. J. & Suslick, K. S. Nanostructured materials through ultrasonic spray pyrolysis. Mater. Matters 7, 19–25 (2012).
Liu, J., Conry, T. E., Song, X., Doeff, M. M. & Richardson, T. J. Nanoporous spherical LiFePO4 for high performance cathodes. Energy Environ. Sci. 4, 885–888 (2011).
Liu, J. et al. Spherical nanoporous LiCoPO4/C composites as high performance cathode materials for rechargeable lithium-ion batteries. J. Mater. Chem. 21, 9984–9987 (2011).
Kao, T. L. et al. Nanoscale elemental sensitivity study of Nd2Fe14B using absorption correlation tomography. Microsc. Res. Tech. 76, 1112–1117 (2013).
Meirer, F. et al. Three-dimensional imaging of chemical phase transformations at the nanoscale with full-field transmission X-ray microscopy. J. Synchrotron Radiat. 18, 773–781 (2011).
Wang, J., Chen-Wiegart, Y. K. & Wang, J. In operando tracking phase transformation evolution of lithium iron phosphate with hard X-ray microscopy. Nature Commun. 5, 4570 (2014).
Gu, M. et al. Conflicting roles of nickel in controlling cathode performance in lithium ion batteries. Nano Lett. 12, 5186–5191 (2012).
Zhou, L., Zhao, D. & Lou, X. LiNi(0.5)Mn(1.5)O4 hollow structures as high-performance cathodes for lithium-ion batteries. Angew. Chem. Int. Ed. 51, 239–241 (2012).
Petersburg, C. F., Li, Z., Chernova, N. A., Whittingham, M. S. & Alamgir, F. M. Oxygen and transition metal involvement in the charge compensation mechanism of LiNi1∕3Mn1∕3Co1∕3O2 cathodes. J. Mater. Chem. 22, 19993–20000 (2012).
Wilcox, J., Patoux, S. & Doeff, M. Structure and electrochemistry of LiNi1∕3Co1∕3−yMyMn1∕3O2 (M = Ti, Al, Fe) positive electrode materials. J. Electrochem. Soc. 156, A192–A198 (2009).
Kang, S.-H., Yoon, W.-S., Nam, K.-W., Yang, X.-Q. & Abraham, D. P. Investigating the first-cycle irreversibility of lithium metal oxide cathodes for Li batteries. J. Mater. Sci. 43, 4701–4706 (2008).
De Groot, F. M. F., Fuggle, J. C., Thole, B. T. & Sawatzky, G. A. 2p x-ray absorption of 3d transition-metal compounds: An atomic multiplet description including the crystal field. Phys. Rev. B 42, 5459–5468 (1990).
Lin, F. et al. Hole doping in Al-containing nickel oxide materials to improve electrochromic performance. ACS Appl. Mater. Interfaces 5, 301–309 (2013).
Lin, F. et al. Origin of electrochromism in high-performing nanocomposite nickel oxide. ACS Appl. Mater. Interfaces 5, 3643–3649 (2013).
Liu, W. et al. Nickel-rich layered lithium transition-metal oxide for high-energy lithium-ion batteries. Angew. Chem. Int. Ed. 54, 4440–4457 (2015).
Liu, Y. et al. Phase retrieval using polychromatic illumination for transmission X-ray microscopy. Opt. Express 19, 540–545 (2011).
Liu, Y. et al. TXM-Wizard: A program for advanced data collection and evaluation in full-field transmission X-ray microscopy. J. Synchrotron Radiat. 19, 281–287 (2012).
This work was supported by the Assistant Secretary for Energy Efficiency and Renewable Energy, Office of Vehicle Technologies of the US Department of Energy under Contract No. DE-AC02-05CH11231. This research used the Hitachi dedicated STEM of the Center for Functional Nanomaterials, which is a US Department of Energy Office of Science Facility, at Brookhaven National Laboratory under Contract No. DE-SC0012704. The synchrotron X-ray portions of this research were carried out at the Stanford Synchrotron Radiation Lightsource, a Directorate of SLAC National Accelerator Laboratory and an Office of Science User Facility operated for the US Department of Energy Office of Science by Stanford University. Use of the Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, is supported by the US Department of Energy, Office of Science, Office of Basic Energy Sciences under Contract No. DE-AC02-76SF00515. F.L. acknowledges J. Xu and C. Tian for valuable discussion. Y.Liu thanks D. Van Campen for valuable discussions and his engineering support for experiments at beamline 6-2C of SSRL. F.L., D.N. and T.-C.W. would like to thank J.-S. Lee and G. Kerr for their assistance at SSRL. This document was prepared as an account of work sponsored by the United States Government. While this document is believed to contain correct information, neither the United States Government nor any agency thereof, nor the Regents of the University of California, nor any of their employees, makes any warranty, express or implied, or assumes any legal responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by its trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favouring by the United States Government or any agency thereof, or the Regents of the University of California. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof or the Regents of the University of California.
The authors declare no competing financial interests.
Supplementary Figures 1–3. (PDF 516 kb)
3D chemical distribution of particles collected directly after spray pyrolysis, before annealing. The particle surfaces are first shown from different angles then the colour-coded distribution of each element is shown as slices, to reveal the interior. (MOV 3207 kb)
3D chemical distribution of particles collected after annealing. The particle surfaces are first shown from different angles then the colour-coded distribution of each element is shown as slices, to reveal the interior. (MOV 5852 kb)
3D chemical associations for an annealed particle. The initial views show the surfaces of the particle from different viewpoints and later views show slices from the interior, also from different vantages. The colour keys are the same as in Figure 2: Mn is blue, Co is red, Ni is green, Mn/Co is purple, Mn/Ni is cyan, Co/Ni is yellow and Mn/Co/Ni is white. (MOV 9752 kb)
About this article
Cite this article
Lin, F., Nordlund, D., Li, Y. et al. Metal segregation in hierarchically structured cathode materials for high-energy lithium batteries. Nat Energy 1, 15004 (2016). https://doi.org/10.1038/nenergy.2015.4
Charge distribution guided by grain crystallographic orientations in polycrystalline battery materials
Nature Communications (2020)
Synergistic coupling effect of single crystal morphology and precursor treatment of Ni-Rich cathode materials
Journal of Alloys and Compounds (2020)
The Effects of Constriction Factor and Geometric Tortuosity on Li‐Ion Transport in Porous Solid‐State Li‐Ion Electrolytes
Advanced Functional Materials (2020)
Crack-free single-crystalline Ni-rich layered NCM cathode enable superior cycling performance of lithium-ion batteries
Nano Energy (2020)