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In the search for new cathode materials with high gravimetric capacity,Li-rich materials Li2MO3(M=Co,Ni,Mn,Mo,Ir,Ru…)have attracted considerable attention for the next generation of the Li-ion batteries.Li4FeSbO6 has a new Li-rich layered oxides antiferromagent honeycomb structure with C2/m monoclinic space group,however the electronic structures and dynamics properties during the charge-discharging cycles are still poorly understood.In this paper,the electrochemical behavior,delithiation structure LixFeSbO6(0≤x≤4)and li-ion diffusion in Li4FeSbO6 are investigated by using the spin-polarized DFT+U and the climbing image nudged elastic band(CI-NEB).The weak hybridization of Fe-3d and O-2p orbitals and semiconductor properties are observed by the density of states.In the charging process,Li4FeSbO6 present excellent volume stability.The average voltage is predicted to range from 4.19 V to 4.69 V,which are quite close to the experimental values.Moreover,we calculate the Bader charge and enthalpy change in the delithiation structures,the results express the possibility of oxygen release reaction will occur spontaneously at a high voltage.Due to the oxygen evolution in LixFeSbO6(x<1.5),it is needed to stabilitize the structure during the charge-discharging cycles.From the CI-NEB method,the lithium ion can diffuse in a three dimensional pathway for the layered Li4FeSbO6 structure,.