Experimental Confirmation of Low Surface Energy in LiCoO₂ and Implications for Lithium Battery Electrodes

Abstract

Water adsorption on the surface of LiCoO2 nanoparticles was investigated. As the water coverage increases the adsorption enthalpy decreases reaching the enthalpy of water condensation (−44 kJ mol−1). The experimentally observed average surface energy corresponding to all facets agree well with those reported from DFT calculations. The observed low surface energy is attributed to the surface Co3+ spin transition in nanophase LiCoO2.

Water‐Based Paintable LiCoO2Microelectrodes: A High‐Rate Li‐Ion Battery Free of Conductive and Binder Additives

“…The ATR‐FTIR spectra of all samples exhibit the fingerprint of R ‐3 m phase of HT‐LiCoO 2 in the 550–700 cm −1 region, where three characteristic bands centered at 558, 584, and 629 cm −1 are identified (asterisks, Figure B). After grinding of LiCoU, four new bands are observed in the 800–1500 cm −1 range (LiCoU45, circles, Figure B); these bands are typically associated to carbonates (CO 3 2− ) .…”

A Layer‐Structured Electrode Material Reformed by a PO4‐O2 Hybrid Framework toward Enhanced Lithium Storage and Stability

“…Unfortunately, the use of LiCoO 2 has been inevitably limited because its stability can be rapidly deteriorated at potentials higher than 4.2 V . Several research groups have reported that the observed poor cycling performance above 4.2 V is caused by a phase transition from a hexagonal phase to a monoclinic phase, which accompanies a volume change of ≈2.6% along the c ‐axis . Other studies demonstrated that the capacity loss of LiCoO 2 above 4.2 V is mainly due to an increase in interfacial impedance between the surface film of the cathode and electrolyte, arising from side reactions involving LiPF 6 ‐based electrolytes and surface impurities generated by air or moisture exposure .…”

Design and Preparation of a Lithium‐rich Layered Oxide Cathode with a Mg‐Concentration‐Gradient Shell for Improved Rate Capability

“…[1][2][3][4] However,t he currently available LIBs are incapable of meeting the changing demands. The technical obstacles are mainly attributed to the limited electrochemical properties of cathode materials, [5] such as low capacity (layered LiCoO 2 ), [6,7] structural vulnerability (spinel LiMn 2 O 4 ), [8,9] and poor conductivity of electron/lithium-ion diffusivity (olivine LiFePO 4 ). [10,11] Among all the cathodem aterials reported so far,l ithium-rich layered oxide materials[ xLi 2 MnO 3 ·(1-x)LiMO 2 ], as as olid solution between layers of Li 2 MnO 3 and LiMO 2 (M = Mn, Ni, Co, and so forth, 0 < x < 1), are recognizedasone of the most promising candidates, because of their low cost and low toxicity,a nd characteristic high specificc apacities ( % 250 mAh g À1 )w hen charged to ah igh upperc utoff voltage (> 4.5 V).…”