Ultra-high nickel material is considered to be a promising cathode material.However,with the increase of nickel content,the interfacial side reactions between the cathode and electrolyte become increasingly serious.He...Ultra-high nickel material is considered to be a promising cathode material.However,with the increase of nickel content,the interfacial side reactions between the cathode and electrolyte become increasingly serious.Herein,an atomically controllable ionic conductor Li_(3)PO_(4)(LPO)coating is deposited on the LiNi_(0.90)Co_(0.06)Mn_(0.04)O_(2)(NCM9064)based electrode by the atomic layer deposition method.The results shows that the LPO coating is uniformly and densely covered on the surface of secondary particles of NCM9064,helping to prevent the direct contact between the electrolyte and cathode during the chargingdischarging process.In addition,the coating layer is electrochemically stable.As a result,the interfacial side reactions during the long cycle are effectively suppressed,and the solid electrolyte interphase layer at the interface is stabilized.The electrode with 20 layers of LPO deposition(ALD-LPO-20)exhibits an excellent capacity retention of 81%after 200 cycles in 2.8-4.3 V at 25℃,which is 18%higher than the unmodified material(ALD-LPO-0).Besides,the moderate LPO coating improves the rate capability and high temperature cycling performance of NCM9064.This study provides a method for the modification of ultra-high nickel cathode materials and corresponding electrodes.展开更多
Ni-rich layered oxide with Ni molar content larger than 90%was regarded as an extremely promising candidate for cathode material applied in lithium-ion batteries owing to the significant discharging capacity and low c...Ni-rich layered oxide with Ni molar content larger than 90%was regarded as an extremely promising candidate for cathode material applied in lithium-ion batteries owing to the significant discharging capacity and low cost.Nevertheless,rigorous cycling attenuation resulted from the crystal structure collapse and unstable particles interface deeply restrained the commercial application.In the work,LiNi_(0.90)Co_(0.05)Mn_(0.05)O_(2) was modified by Ta5+doping and Li_(2)MnO_(3) covering,which was aimed to enhance the structure stability,defend the electrolyte attacking and promote Li+migration during cycling.The material characterization demonstrated the cathodes after Ta5+doping delivered the larger cell lattice parameters and higher cation ordering,which was helpful to improve the rate property and discharge capacity at low temperature.The Li_(2)MnO_(3) layer was tightly adhered on the outside of LiNi_(0.90)Co_(0.05)Mn_(0.05)O_(2),which could effectively relieve the electrolyte attacking and sustain the particle morphology integrity.As a result,2 wt%Li_(2)MnO_(3) coated Li(Ni_(0.90)Co_(0.05)Mn_(0.05))_(0.98)Ta_(0.02)O_(2) exhibited the outstanding discharge capacity of 150.2 mAh g^(−1) at 10.0 large current density and 140.6 mAh g^(−1) at−30℃ as well as the remarkable capacity retention of 93.1%after 300 cycles.Meanwhile,the pouch full batteries obtained by 2 wt%Li_(2)MnO_(3) coated Li(Ni_(0.90)Co_(0.05)Mn_(0.05))_(0.98)Ta_(0.02)O_(2) also showed the more stable storage capability,cyclic property in comparison with bare LiNi_(0.90)Co_(0.05)Mn_(0.05)O_(2).展开更多
Ba0.85Ca0.15Zr0.10Ti0.90O3(BCZT)lead-free ceramics demonstrated excellent dielectric,ferroelectric,and piezoelectric properties at the morphotropic phase boundary(MPB).So far,to study the effect of morphological chang...Ba0.85Ca0.15Zr0.10Ti0.90O3(BCZT)lead-free ceramics demonstrated excellent dielectric,ferroelectric,and piezoelectric properties at the morphotropic phase boundary(MPB).So far,to study the effect of morphological changes on dielectric and ferroelectric properties in lead-free BCZT ceramics,researchers have mostly focused on the influence of spherical grain shape change.In this study,BCZT ceramics with rod-like grains and aspect ratio of about 10 were synthesized by surfactant-assisted solvothermal route.X-ray diffraction(XRD)and selected area electron diffraction(SAED)performed at room temperature confirm the crystallization of pure perovskite with tetragonal symmetry.Scanning electron microscopy(SEM)image showed that BCZT ceramics have kept the 1D rod-like grains with an average aspect ratio of about 4.Rod-like BCZT ceramics exhibit enhanced dielectric ferroelectric(εr=11,906,tanδ=0.014,Pr=6.01μC/cm^2,and Ec=2.46 kV/cm),and electrocaloric properties(ΔT=0.492 K andz=0.289(K×mm)/kV at 17 kV/cm)with respect to spherical BCZT ceramics.Therefore,rod-like BCZT lead-free ceramics have good potential to be used in solid-state refrigeration technology.展开更多
基金supported by the National Natural Science Foundation of China(No.52174285)the Science and Technology Innovation Program of Hunan Province(No.2022RC3048)+1 种基金the Key Research and Development Program of Yunnan Province(No.202103AA080019)the Research Foundation of Education Bureau of Hunan Province(No.18B477).
文摘Ultra-high nickel material is considered to be a promising cathode material.However,with the increase of nickel content,the interfacial side reactions between the cathode and electrolyte become increasingly serious.Herein,an atomically controllable ionic conductor Li_(3)PO_(4)(LPO)coating is deposited on the LiNi_(0.90)Co_(0.06)Mn_(0.04)O_(2)(NCM9064)based electrode by the atomic layer deposition method.The results shows that the LPO coating is uniformly and densely covered on the surface of secondary particles of NCM9064,helping to prevent the direct contact between the electrolyte and cathode during the chargingdischarging process.In addition,the coating layer is electrochemically stable.As a result,the interfacial side reactions during the long cycle are effectively suppressed,and the solid electrolyte interphase layer at the interface is stabilized.The electrode with 20 layers of LPO deposition(ALD-LPO-20)exhibits an excellent capacity retention of 81%after 200 cycles in 2.8-4.3 V at 25℃,which is 18%higher than the unmodified material(ALD-LPO-0).Besides,the moderate LPO coating improves the rate capability and high temperature cycling performance of NCM9064.This study provides a method for the modification of ultra-high nickel cathode materials and corresponding electrodes.
基金supported by the Natural Science Research Projects of Colleges and Universities in Jiangsu Province (grant No.24KJA430012)the Open Project Program of Key Laboratories of Fine Chemicals and Surfactants in Sichuan Provincial Universities (grant No.SCFY2203).
文摘Ni-rich layered oxide with Ni molar content larger than 90%was regarded as an extremely promising candidate for cathode material applied in lithium-ion batteries owing to the significant discharging capacity and low cost.Nevertheless,rigorous cycling attenuation resulted from the crystal structure collapse and unstable particles interface deeply restrained the commercial application.In the work,LiNi_(0.90)Co_(0.05)Mn_(0.05)O_(2) was modified by Ta5+doping and Li_(2)MnO_(3) covering,which was aimed to enhance the structure stability,defend the electrolyte attacking and promote Li+migration during cycling.The material characterization demonstrated the cathodes after Ta5+doping delivered the larger cell lattice parameters and higher cation ordering,which was helpful to improve the rate property and discharge capacity at low temperature.The Li_(2)MnO_(3) layer was tightly adhered on the outside of LiNi_(0.90)Co_(0.05)Mn_(0.05)O_(2),which could effectively relieve the electrolyte attacking and sustain the particle morphology integrity.As a result,2 wt%Li_(2)MnO_(3) coated Li(Ni_(0.90)Co_(0.05)Mn_(0.05))_(0.98)Ta_(0.02)O_(2) exhibited the outstanding discharge capacity of 150.2 mAh g^(−1) at 10.0 large current density and 140.6 mAh g^(−1) at−30℃ as well as the remarkable capacity retention of 93.1%after 300 cycles.Meanwhile,the pouch full batteries obtained by 2 wt%Li_(2)MnO_(3) coated Li(Ni_(0.90)Co_(0.05)Mn_(0.05))_(0.98)Ta_(0.02)O_(2) also showed the more stable storage capability,cyclic property in comparison with bare LiNi_(0.90)Co_(0.05)Mn_(0.05)O_(2).
基金The authors gratefully acknowledge the generous financial support of CNRST Priority Program(PPR 15/2015)Slovenian Research Agency Program(P1-0125)European Union’s Horizon 2020 Research and Innovation Program under the Marie Skłodowska-Curie Grant Agreement(No.778072).
文摘Ba0.85Ca0.15Zr0.10Ti0.90O3(BCZT)lead-free ceramics demonstrated excellent dielectric,ferroelectric,and piezoelectric properties at the morphotropic phase boundary(MPB).So far,to study the effect of morphological changes on dielectric and ferroelectric properties in lead-free BCZT ceramics,researchers have mostly focused on the influence of spherical grain shape change.In this study,BCZT ceramics with rod-like grains and aspect ratio of about 10 were synthesized by surfactant-assisted solvothermal route.X-ray diffraction(XRD)and selected area electron diffraction(SAED)performed at room temperature confirm the crystallization of pure perovskite with tetragonal symmetry.Scanning electron microscopy(SEM)image showed that BCZT ceramics have kept the 1D rod-like grains with an average aspect ratio of about 4.Rod-like BCZT ceramics exhibit enhanced dielectric ferroelectric(εr=11,906,tanδ=0.014,Pr=6.01μC/cm^2,and Ec=2.46 kV/cm),and electrocaloric properties(ΔT=0.492 K andz=0.289(K×mm)/kV at 17 kV/cm)with respect to spherical BCZT ceramics.Therefore,rod-like BCZT lead-free ceramics have good potential to be used in solid-state refrigeration technology.
