Related papers: Flexo-diffusion effect: the strong influence on li…
Nickel-rich layered oxides have been widely used as positive electrode materials for high-energy-density lithium-ion batteries, but their degradation has severely affected cell performance, in particular at a high voltage and temperature.…
Muon spin spectroscopy ($\mu^+$SR) is now an established method to measure atomic scale diffusion coefficients of ions in oxides. This is achieved via the ion hopping rate, which causes periodic change in the local magnetic field at the…
Effective passivation of lithium metal surfaces, and prevention of battery-shorting lithium dendrite growth, are critical for implementing lithium-metal-anodes for batteries with increased power densities. Nanoscale surface heterogeneities…
Room-temperature (RT) conductivity of most candidates for solid electrolytes of miniaturized lithium-ion batteries is still 1-2 orders of magnitude below commercial requirements, therefore several approaches are being pursued aiming the…
The electronic wavefunctions in moir\'e materials are highly sensitive to the details of the local atomic configuration enabling Bloch band geometry and topology to be controlled by stacking and strain. Here we predict that large injection…
We investigate the chemisorptions of oxygen molecules on bilayer graphene (BLG) and its electrically modified charge-doping effect using conductivity measurement of the field effect transistor channeled with BLG. We demonstrate that the…
Twisted graphene bilayers show a complex electronic structure, further modified by interaction effects. The main features can be obtained from effective models, which make use a few phenomenological parameters. We analyze the influence of…
Lithium (Li) metal anodes are essential for developing next-generation high-energy-density batteries. However, Li dendrite/whisker formation caused short-circuiting issue and short cycle life have prevented lithium metal from being viably…
The flexoelectric behaviors of solids under high strain gradient can be distinct from that under low strain gradient. Using the generalized Bloch theorem, we investigate theoretically the transversal flexoelectric effects in bent MgO…
Effect of electric field on the band structures of graphene/BN and BN/BN bilayers is investigated within the framework of density functional theory. A relatively large degree of modulation is predicted for the graphene/BN bilayer. The…
Graphite fluoride (CFx) cathodes coupled with lithium anodes yield one of the highest theoretical energy densities (>860 Wh/g) among primary batteries. In practice, the observed discharge voltage (~2.5 V) is significantly lower than…
We report the lithium plating associated capacity loss during fast charging of compressively loaded lithium-ion batteries (LIBs). The charging and discharging of LIB under compressive loading during service may affect the cell performance…
The prospects of phosphorene as an anode material for high performance Li-ion battery was systematically investigated from the first principle calculations and experimental measurements. The diffusion energy barriers of a Li atom moving…
The solid-state diffusion coefficient of the electrode active material is one of the key parameters in lithium-ion battery modelling. Conventionally, this diffusion coefficient is estimated through the galvanostatic intermittent titration…
Core-shell electrode particle designs offer a route to improved lithium-ion battery performance. However, they are susceptible to mechanical damage such as fracture and debonding, which can significantly reduce their lifetime. Using a…
In this paper we study the effect of a fluctuating gap in mono- and bilayer graphene, created by a random staggered potential. We identify a continuous symmetry for the two-particle Green's function which is spontaneously broken in the…
Tunneling conductance between two bilayer graphene (BLG) sheets separated by 2 nm-thick insulating barrier was measured in two devices with the twist angles between BLGs less than 1{\deg}. At small bias voltages, the tunneling occurs with…
This study reports on advancements in operando characterization of volume changes in lithium-ion battery (LIB) electrode materials during electrochemical cycling. Volume changes are crucial for LIB operation because they are related to the…
We reveal that strong flexoelectric effect of solids can be induced due to the signfi?cant charge migration along the strain gradient direction, which represents a new understanding of the origin of flexoelectricity. Beyond the linear…
The diffusion coefficient of Li$^+$ ions ($D_{\rm Li}$) in the battery material Li$_x$CoO$_2$ has been investigated by muon-spin relaxation ($\mu^+$SR). Based on the experiments in zero-field and weak longitudinal-fields at temperatures up…