RECENT ADVANCES ON STUDIES OF LITHIUM-ION BATTERIES IN BAR-ILAN UNIVERSITY: PART II. STUDIES OF Li,Mn-Rich MATERIALS – SYNTHESIS, STRUCTURE, ELECTROCHEMICAL BEHAVIOR

Hadar Sclar ¹ Francis Amalraj Susai ¹ Florian Schipper ¹ Evan Erickson ¹ Judith Grinblat ¹ Michael Talianker ² Penki Tirupathi Rao ¹ Nayak Prasant Kumar ¹ Dan T. Major ¹ Boris Markovsky ¹ Doron Aurbach ¹

¹Department of Chemistry, Bar-Ilan University, Ramat-Gan, Israel
²Department of Materials Engineering, Ben-Gurion University of the Negev, Beer-Sheva, Israel

This presentation summarizes the recent studies in Bar-Ilan University of materials for positive electrodes of Li-ion batteries. The materials included lithiated oxides of Li-Mn-rich layered-layered xLi₂MnO₃^.(1-x)LiMO₂ (M=Ni, Co, Mn), 03-coated electrodes exhibit stable charge-discharge behavior providing higher capacities and lower fade upon prolonged cycling at 60◦C. It has been found that electrodes comprising the AlF₃-coated material exhibited higher reversible capacities of ∼250 mAh/g at a C/5 rate, more stable cycling behavior, higher lithium storage capability at 60^oC, and lower impedance measured during Li-deinteraclation comparing to electrodes prepared from the uncoated material. An important finding is that Li_x[MnNiCo]O₂ /AlF₃ materials revealed much higher thermal stability both in the pristine (lithiated) and cycled (delithiated) states than their uncoated counterparts [1]. Ammonia treatments of Li,Mn-rich materials improve discharge capacity, as well as the fading of discharge capacity and voltage. The mechanism of the ammonia treatment will be discussed. Further work will explore full cell studies to confirm if NH₃ treatment can indeed improve the likelihood of commercialization of the above materials [2].

[1] F. Amalraj, M. Talianker, B. Markovsky et al. J. Electrochem. Soc. 160 (2013) A2220.

[2] Evan M. Erickson, Hadar Sclar, Florian Schipper, B. Markovsky et al., Adv. Energy Mater., 7, (2017) 1700708