Atomic-Scale Mechanisms of Enhanced Electrochemical Properties of Mo-Doped Co-Free Layered Oxide Cathodes for Lithium-Ion Batteries

Journal Article · Tue Sep 24 04:00:00 EDT 2019 · ACS Energy Letters

DOI:https://doi.org/10.1021/acsenergylett.9b01830· OSTI ID:1579926

Li, Linze ^[1]; Yu, Jianguo ^[2]; Darbar, Devendrasinh ^[3]; Self, Ethan C. ^[4]; Wang, Donghai ^[5]; Nanda, Jagjit ^[4]; Bhattacharya, Indranil ^[6]; Wang, Chongmin ^[7]

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1. Pacific Northwest National Lab. (PNNL), Richland, WA (United States); THE PENNSYLVANIA STATE UNIVERSITY, DEPARTMENT OF MECHANICAL ENGINEERING, UNIVERSITY PARK, PA 16802
2. Idaho National Lab. (INL), Idaho Falls, ID (United States)
3. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Tennessee Technological Univ., Cookeville, TN (United States)
4. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
5. Pennsylvania State Univ., University Park, PA (United States)
6. Tennessee Technological Univ., Cookeville, TN (United States)
7. Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

Cobalt-free layered oxides have emerged as promising candidates for next-generation cathodes for lithium-ion batteries. However, implementation of these materials has been hindered by their low rate capability, structural instability, and rapid capacity decay during cycling. Recent studies have shown that introducing cation dopants into layered oxides can strongly improve their electrochemical properties, but the underlying atomic-scale mechanisms remain elusive. As such, in this work, we use a combination of atomic-resolution scanning transmission electron microscopy and first-principle calculations to reveal the microscopic origin of enhanced electrochemical properties in LiNi_0.5Mn_0.5O₂ doped with ~1 atom % Mo. Our results indicate that the Mo dopant hinders Li⁺/Ni₂⁺ cation mixing and suppresses detrimental phase transformations near the particle surface and at intragranular grain boundaries, which enhances the cathode’s reversible capacity and cycling stability. Overall, this work provides important insights on how cation doping affects the structure and electrochemical properties of layered oxide cathodes.

• Research Organization: Pennsylvania State Univ., University Park, PA (United States)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE), Vehicle Technologies Office (EE-3V)
• Grant/Contract Number: EE0008447
• OSTI ID: 1579926
• Alternate ID(s): OSTI ID: 1606764; OSTI ID: 1577843
• Journal Information: ACS Energy Letters, Journal Name: ACS Energy Letters Journal Issue: 10 Vol. 4; ISSN 2380-8195
• Publisher: American Chemical Society (ACS)
• Country of Publication: United States
• Language: English

Related Subjects

25 ENERGY STORAGE
Cobalt-free layered oxides
Lithium-Ion Batteries
Mo-doped Co-free Layered Oxide Cathodes
cation doping
layered oxide cathodes