title: High-Capacity Layered-Spinel Cathodes for Li-Ion Batteries.
abstract: Li and Mn-rich layered oxides with the general structure x Li2 MnO3 ⋅(1-x) LiMO2 (M=Ni, Mn, Co) are promising cathode materials for Li-ion batteries because of their high specific capacity, which may be greater than 250 mA h g(-1) . However, these materials suffer from high first-cycle irreversible capacity, gradual capacity fading, limited rate capability and discharge voltage decay upon cycling, which prevent their commercialization. The decrease in average discharge voltage is a major issue, which is ascribed to a structural layered-to-spinel transformation upon cycling of these oxide cathodes in wide potential ranges with an upper limit higher than 4.5 V and a lower limit below 3 V versus Li. By using four elements systems (Li, Mn, Ni, O) with appropriate stoichiometry, it is possible to prepare high capacity composite cathode materials that contain LiMn1.5 Ni0.5 O4 and Lix Mny Niz O2 components. The Li and Mn-rich layered-spinel cathode materials studied herein exhibit a high specific capacity (≥200 mA h g(-1) ) with good capacity retention upon cycling in a wide potential domain (2.4-4.9 V). The effect of constituent phases on their electrochemical performance, such as specific capacity, cycling stability, average discharge voltage, and rate capability, are explored here. This family of materials can provide high specific capacity, high rate capability, and promising cycle life. Using Co-free cathode materials is also an obvious advantage of these systems.
authors.affiliation: Department of Chemistry, Bar-Ilan University, Ramat-Gan, 5290002, Israel.
authors.forename: Prasant Kumar
authors.initials: PK
authors.lastname: Nayak
authors.affiliation: Department of Chemistry, Bar-Ilan University, Ramat-Gan, 5290002, Israel.
authors.forename: Elena
authors.initials: E
authors.lastname: Levi
authors.affiliation: Department of Chemistry, Bar-Ilan University, Ramat-Gan, 5290002, Israel.
authors.forename: Judith
authors.initials: J
authors.lastname: Grinblat
authors.affiliation: Department of Chemistry, Bar-Ilan University, Ramat-Gan, 5290002, Israel.
authors.forename: Mikhael
authors.initials: M
authors.lastname: Levi
authors.affiliation: Department of Chemistry, Bar-Ilan University, Ramat-Gan, 5290002, Israel.
authors.forename: Boris
authors.initials: B
authors.lastname: Markovsky
authors.affiliation: Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore, 560012, India.
authors.forename: N
authors.initials: N
authors.lastname: Munichandraiah
authors.affiliation: Department of Energy Engineering, Hanyang University, 133-791, Republic of Korea.
authors.forename: Yang Kook
authors.initials: YK
authors.lastname: Sun
authors.affiliation: Department of Chemistry, Bar-Ilan University, Ramat-Gan, 5290002, Israel. Doron.Aurbach@mail.biu.ac.il.
authors.forename: Doron
authors.initials: D
authors.lastname: Aurbach
mesh_terms: D000537:Aluminum Oxide / Q000737:chemistry*; D011211:Electric Power Supplies; D004563:Electrochemistry; D004566:Electrodes; D008094:Lithium / Q000737:chemistry*; D008277:Magnesium Oxide / Q000737:chemistry*
chemical_list: C111130:spinell; D008277:Magnesium Oxide; D008094:Lithium; D000537:Aluminum Oxide
keywords: batteries; high capacity; layered-spinel composites; lithium-insertion electrodes; lithium-ion