A Ti-BN complex cathode is made from Ti and h-BN powders by the powder metallurgy technology, and TiBN coating is obtained by plasma immersion ion implantation and deposition with this Ti-BN composite cathode. The TiB...A Ti-BN complex cathode is made from Ti and h-BN powders by the powder metallurgy technology, and TiBN coating is obtained by plasma immersion ion implantation and deposition with this Ti-BN composite cathode. The TiBN coating shows a self-forming multilayered nanocomposite structure while with relative uniform elemental distributions. High resolution transmission electron microscopy images reveal that the multilayered structure is derived from different grain sizes in the nanocomposite. Due to the existence of h-BN phase, the friction coefficient of the coating is about 0.25.展开更多
Experimental investigations and associated methods are provided to characterize the mechanical properties of a lithium-ion battery accounting for operating temperature variation and thermal effects. Material propertie...Experimental investigations and associated methods are provided to characterize the mechanical properties of a lithium-ion battery accounting for operating temperature variation and thermal effects. Material properties for LiFeP04 cathode and anode samples taken from an off-the-shelf battery are evaluated in new and fatigued (subjec- ted to charging and discharging cycles) conditions.展开更多
Nano-sized LiFePO_4·Li_3V_2(PO_4)_3/C was synthesized via a sol-gel route combining with freeze-drying. X-ray diffraction results show that this composite mainly consists of olivine Li Fe PO4 and monoclinic Li3...Nano-sized LiFePO_4·Li_3V_2(PO_4)_3/C was synthesized via a sol-gel route combining with freeze-drying. X-ray diffraction results show that this composite mainly consists of olivine Li Fe PO4 and monoclinic Li3 V2(PO4)3 phases with small amounts of V-doped LiFePO_4 and Fe-doped Li_3V_2(PO_4)_3. The magnetic properties of LiFePO_4·Li_3V_2(PO_4)_3/C are significantly different from LiFePO_4/C. Trace quantities of ferromagnetic impurities and Fe_2P are verified in LiFePO_4/C and LiFePO_4·Li_3V_2(PO_4)_3/C by magnetic tests, respectively. LiFePO_4·Li_3 V_2(PO_4)_3/C possesses relatively better rate capacities and cyclic stabilities, especially at high charge-discharge rates.The initial discharge capacities are 136.4 and 130.0 mA h g^(-1),and the capacity retentions are more than 98% after 100 cycles at 2C and 5C, respectively, remarkably better than those of LiFePO_4/C. The excellent electrochemical performances are ascribed to the mutual doping of V^(3+)and Fe^(2+), complementary advantages of LiFePO_4 and Li_3V_2(PO_4)_3 phases, the residual high-ordered carbon and Fe_2P with outstanding electric conductivity in the nanocomposite.展开更多
基金Supported by the Fund of National Key Laboratory of High Power Microwave Technology under Grant No 2014-763.xy.kthe National Natural Science Foundation of China under Grant No 21573054the Joint Funds Key Project of the National Natural Science Foundation of China under Grant No U1537214
文摘A Ti-BN complex cathode is made from Ti and h-BN powders by the powder metallurgy technology, and TiBN coating is obtained by plasma immersion ion implantation and deposition with this Ti-BN composite cathode. The TiBN coating shows a self-forming multilayered nanocomposite structure while with relative uniform elemental distributions. High resolution transmission electron microscopy images reveal that the multilayered structure is derived from different grain sizes in the nanocomposite. Due to the existence of h-BN phase, the friction coefficient of the coating is about 0.25.
基金the National Science Foundation and Advanced Technologies(NFSAT),the grant No.TFP-12-06supported by Clarkson University Mechanical and Aeronautical Engineering Department,and Clarkson University Center for Advanced Material Processing
文摘Experimental investigations and associated methods are provided to characterize the mechanical properties of a lithium-ion battery accounting for operating temperature variation and thermal effects. Material properties for LiFeP04 cathode and anode samples taken from an off-the-shelf battery are evaluated in new and fatigued (subjec- ted to charging and discharging cycles) conditions.
基金supported by the National Natural Science Foundation of China (21673051)Guangdong Province Science & Technology Bureau (2014A010106029, 2014B010106005 and 2016A010104015)+3 种基金Guangzhou Science & Innovative Committee (201604030037)the Youth Foundation of Guangdong University of Technology (252151038)the link project of the National Natural Science Foundation of China and Guangdong Province (U1401246)the Science and Technology Program of Guangzhou City of China (201508030018)
文摘Nano-sized LiFePO_4·Li_3V_2(PO_4)_3/C was synthesized via a sol-gel route combining with freeze-drying. X-ray diffraction results show that this composite mainly consists of olivine Li Fe PO4 and monoclinic Li3 V2(PO4)3 phases with small amounts of V-doped LiFePO_4 and Fe-doped Li_3V_2(PO_4)_3. The magnetic properties of LiFePO_4·Li_3V_2(PO_4)_3/C are significantly different from LiFePO_4/C. Trace quantities of ferromagnetic impurities and Fe_2P are verified in LiFePO_4/C and LiFePO_4·Li_3V_2(PO_4)_3/C by magnetic tests, respectively. LiFePO_4·Li_3 V_2(PO_4)_3/C possesses relatively better rate capacities and cyclic stabilities, especially at high charge-discharge rates.The initial discharge capacities are 136.4 and 130.0 mA h g^(-1),and the capacity retentions are more than 98% after 100 cycles at 2C and 5C, respectively, remarkably better than those of LiFePO_4/C. The excellent electrochemical performances are ascribed to the mutual doping of V^(3+)and Fe^(2+), complementary advantages of LiFePO_4 and Li_3V_2(PO_4)_3 phases, the residual high-ordered carbon and Fe_2P with outstanding electric conductivity in the nanocomposite.