Among all the issues that restrict the application of Li-air battery, poor power performances of O2 cathode comes first. In this paper, we establish carbon (Super P)/LiMxOy (LiMn2O4/LiFePO4/LiNi1/3Co1/3Mn1/3O2) hybrid...Among all the issues that restrict the application of Li-air battery, poor power performances of O2 cathode comes first. In this paper, we establish carbon (Super P)/LiMxOy (LiMn2O4/LiFePO4/LiNi1/3Co1/3Mn1/3O2) hybrid cathode to promote the power output of conventional carbon cathode through continuous Li+-insertion reaction of LiMxOy and Li+ transportation in bulk LiMxOy during the discharging process. Weight and volume specific power performances of the hybrid cathode are much higher than those of traditional Super P carbon cathode. The mechanism of improving power performance of O2 cathode has also been discussed through electrochemical impedance spectroscopy and cyclic voltammetry method in this paper.展开更多
The Ni-richLiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)layered cathodes endow Li-ion batteries(LIBs)with high energy density.However,they usually suffer from limited ion-diffusion and structural instability during cycling....The Ni-richLiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)layered cathodes endow Li-ion batteries(LIBs)with high energy density.However,they usually suffer from limited ion-diffusion and structural instability during cycling.Although doping strategy can effectively alleviate these issues,the coupling effects of multi-element doping and the corresponding performance enhancement mechanism have been yet unclear.Here,we report a Zr/Ti dual-doped NCM811 cathode material(ZT-NCM811),in which Zr-ion is doped into both transition metal(TM)layers and lithium layers and Ti-ion is only distributed in TM layers.The dual-doping can effectively enhance crystal structure stability via inhibiting the lattice collapse along c-axis and decreasing the Li/Ni disorder.Meantime,the lattice oxygen escape is also greatly reduced due to the presence of stronger Zr-O and Ti-O bonds,further mitigating the crystal surface parasitic reactions with electrolyte.The resultant ZT-NCM811 exhibits high specific capacity of 124 m Ah/g at even 10 C,much higher than undoped and single-doped NCM811,and a retention of 98.8%at 1 C after 100 cycles.The assembled ZT-NCM811/graphite full cell also delivers superior battery performances and durability.展开更多
Vehicle to grid is an emerging technology that utilizes plug in hybrid electric vehicle batteries to benefit electric utilities during times when the vehicle is parked and connected to the electric grid. In its curren...Vehicle to grid is an emerging technology that utilizes plug in hybrid electric vehicle batteries to benefit electric utilities during times when the vehicle is parked and connected to the electric grid. In its current form however, vehicle to grid implementation poses many challenges that may not be easily overcome and many existing studies neglect critical aspects such as battery cost or driving profiles. The goal of this research is to ease some of these challenges by examining a vehicle to grid scenario on a university campus, as an example of a commercial campus, based on time of use electricity rates. An analysis of this scenario is conducted on a vehicle battery as well as a stationary battery for comparison. It is found that vehicle to campus and a stationary battery both have the potential to prove economical based on battery cost and electricity rates.展开更多
针对电动汽车动力电池组的管理需求,设计了一款基于MC9S12XEP100和LTC6804的锂电池管理系统,实现对单体电池电压、电流和温度实时监控、电压均衡管理、热管理、充放电管理、数据存储和上位机显示功能。针对电池荷电状态(state of charge...针对电动汽车动力电池组的管理需求,设计了一款基于MC9S12XEP100和LTC6804的锂电池管理系统,实现对单体电池电压、电流和温度实时监控、电压均衡管理、热管理、充放电管理、数据存储和上位机显示功能。针对电池荷电状态(state of charge,SOC)估算精度和实时性方面的问题,提出了一种新颖的开路电压和安时积分融合型SOC估算方法,有效减小了开路电压处于平台期造成的误差影响。采用Arbin电池测试设备对上述功能和SOC估计方法进行了测试验证。结果显示,电池电压误差小于0.07 V,温度误差小于1℃,SOC估算误差小于1.2%,因此,设计系统可用于实际电动汽车动力电池组管理,实现电池SOC实时在线准确估计。展开更多
氧化铋(Bi_2O_3)作为碱性镍/铋电池的负极材料,因其理论容量高、易制备而受到广泛关注.然而,金属氧化物普遍较差的导电性以及氧化铋的循环不稳定性严重限制了器件的性能.本文用直接生长的具有动力学优势的氧化铋纳米片薄膜作为镍/铋电...氧化铋(Bi_2O_3)作为碱性镍/铋电池的负极材料,因其理论容量高、易制备而受到广泛关注.然而,金属氧化物普遍较差的导电性以及氧化铋的循环不稳定性严重限制了器件的性能.本文用直接生长的具有动力学优势的氧化铋纳米片薄膜作为镍/铋电池的负极;同时将葡萄糖衍生的碳包覆在纳米片的表面,不仅促进了电子传递,还缓冲了氧化铋转换反应过程中的体积膨胀,有助于维持电极的循环稳定性.该Bi_2O_3@C电极表现出高比容量,优异的倍率性能(在6.7 s内充满电)以及良好的循环稳定性(约1200次;每圈仅衰减0.011%).与氧化镍(NiO)纳米片阵列正极搭配,组装的完全无粘结剂的碱性镍/铋电池展现出34.29 W h kg^(-1)的最大能量密度和12159.8 W kg^(-1)的最大功率密度以及良好的循环性能;其功率密度甚至远远优于许多混合/非对称型超级电容器.本研究展现了新一代薄膜镍/铋电池在高功率电子器件应用上的巨大潜力.展开更多
文摘Among all the issues that restrict the application of Li-air battery, poor power performances of O2 cathode comes first. In this paper, we establish carbon (Super P)/LiMxOy (LiMn2O4/LiFePO4/LiNi1/3Co1/3Mn1/3O2) hybrid cathode to promote the power output of conventional carbon cathode through continuous Li+-insertion reaction of LiMxOy and Li+ transportation in bulk LiMxOy during the discharging process. Weight and volume specific power performances of the hybrid cathode are much higher than those of traditional Super P carbon cathode. The mechanism of improving power performance of O2 cathode has also been discussed through electrochemical impedance spectroscopy and cyclic voltammetry method in this paper.
基金supported by the National Natural Science Foundation of China(Nos.21975074,91834301)the Innovation Program of Shanghai Municipal Education Commissionthe Fundamental Research Funds for the Central Universities。
文摘The Ni-richLiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)layered cathodes endow Li-ion batteries(LIBs)with high energy density.However,they usually suffer from limited ion-diffusion and structural instability during cycling.Although doping strategy can effectively alleviate these issues,the coupling effects of multi-element doping and the corresponding performance enhancement mechanism have been yet unclear.Here,we report a Zr/Ti dual-doped NCM811 cathode material(ZT-NCM811),in which Zr-ion is doped into both transition metal(TM)layers and lithium layers and Ti-ion is only distributed in TM layers.The dual-doping can effectively enhance crystal structure stability via inhibiting the lattice collapse along c-axis and decreasing the Li/Ni disorder.Meantime,the lattice oxygen escape is also greatly reduced due to the presence of stronger Zr-O and Ti-O bonds,further mitigating the crystal surface parasitic reactions with electrolyte.The resultant ZT-NCM811 exhibits high specific capacity of 124 m Ah/g at even 10 C,much higher than undoped and single-doped NCM811,and a retention of 98.8%at 1 C after 100 cycles.The assembled ZT-NCM811/graphite full cell also delivers superior battery performances and durability.
文摘Vehicle to grid is an emerging technology that utilizes plug in hybrid electric vehicle batteries to benefit electric utilities during times when the vehicle is parked and connected to the electric grid. In its current form however, vehicle to grid implementation poses many challenges that may not be easily overcome and many existing studies neglect critical aspects such as battery cost or driving profiles. The goal of this research is to ease some of these challenges by examining a vehicle to grid scenario on a university campus, as an example of a commercial campus, based on time of use electricity rates. An analysis of this scenario is conducted on a vehicle battery as well as a stationary battery for comparison. It is found that vehicle to campus and a stationary battery both have the potential to prove economical based on battery cost and electricity rates.
文摘针对电动汽车动力电池组的管理需求,设计了一款基于MC9S12XEP100和LTC6804的锂电池管理系统,实现对单体电池电压、电流和温度实时监控、电压均衡管理、热管理、充放电管理、数据存储和上位机显示功能。针对电池荷电状态(state of charge,SOC)估算精度和实时性方面的问题,提出了一种新颖的开路电压和安时积分融合型SOC估算方法,有效减小了开路电压处于平台期造成的误差影响。采用Arbin电池测试设备对上述功能和SOC估计方法进行了测试验证。结果显示,电池电压误差小于0.07 V,温度误差小于1℃,SOC估算误差小于1.2%,因此,设计系统可用于实际电动汽车动力电池组管理,实现电池SOC实时在线准确估计。
基金supported by grants from the National Natural Science Foundation of China (51672205)the National Key R&D Program of China (2016YFA0202602)the Research Start-Up Fund from Wuhan University of Technology
文摘氧化铋(Bi_2O_3)作为碱性镍/铋电池的负极材料,因其理论容量高、易制备而受到广泛关注.然而,金属氧化物普遍较差的导电性以及氧化铋的循环不稳定性严重限制了器件的性能.本文用直接生长的具有动力学优势的氧化铋纳米片薄膜作为镍/铋电池的负极;同时将葡萄糖衍生的碳包覆在纳米片的表面,不仅促进了电子传递,还缓冲了氧化铋转换反应过程中的体积膨胀,有助于维持电极的循环稳定性.该Bi_2O_3@C电极表现出高比容量,优异的倍率性能(在6.7 s内充满电)以及良好的循环稳定性(约1200次;每圈仅衰减0.011%).与氧化镍(NiO)纳米片阵列正极搭配,组装的完全无粘结剂的碱性镍/铋电池展现出34.29 W h kg^(-1)的最大能量密度和12159.8 W kg^(-1)的最大功率密度以及良好的循环性能;其功率密度甚至远远优于许多混合/非对称型超级电容器.本研究展现了新一代薄膜镍/铋电池在高功率电子器件应用上的巨大潜力.