锂离子电池和双电层电容器用LiODFB-TEABF4复合盐电解液的研究

探讨在EC+PC+DMC复合溶剂体系中LiODFB-TEABF4复合盐电解液与LiFePO4锂离子电池及AC双电层电容器的相容性规律.研究结果表明:在LiODFB基电解液中加入TEABF4能显著提高电解液的电导率;对于LiFePO4电池体系,电解液中的TEABF4参与了SEI膜的成膜过程,但TEABF4浓度过高不利于电极材料的容量的提高;对于AC电容器体系,加入TEABF4可以有效改善电容器的双电层储能行为,同时显著提高电容,当TEABF4浓度为0.3 mol/L时,电容达到最大,比不添加TEABF4的纯LiODFB盐电解液的电容大.     

Synthesis/Structure and Cathode Properties of Li_2CoPO_4F for High-Voltage Li-ion Batteries

1 Results Although phospho-olivine LiFePO4 has attracted much attention as next-generation cathode, the gravimetric energy density is restricted. Fluorophosphate Li2CoPO4F is strong candidate for new high-voltage cathode with large capacity,if 2 Li can be reversibly removed[1]. In the present study, we tried to synthesized Li2CoPO4F by two methods, solid state reaction in vacuumed quartz tube with Pt crucible and melt-quench process using Cu single roller in Ar. The obtained latter amorphous sample was...     

单节锂离子电池保护电路的改进

提出了一种低成本的单节锂电池保护回路系统,采用0.6μm混合信号CMOS工艺和修调技术使芯片具有低功耗、高精度检测电压等特点.通过基准电路和取样电路设计的改进,使保护电路实现了多种保护功能,并且具有很高的检测电压精度.模拟结果表明,该电路在温度为25℃时过充电保护电压的检测精度达到了±25mV,耗电流仅为3.5μA,满足高精度检测电压的要求.     

锰酸锂正极锂离子二次电池纯电动汽车的研制

以100Ah的锰酸锂锂离子二次电池锂离子电池组和30kW交流电机组成了动力系统,研制了MGL6486EV电动汽车。电池组的电压为304V,能量为37kWh,电池组采用了智能管理系统(BMS)和均衡系统。电动机采用全数字适量控制,并具有刹车能量回收和防溜车功能。在充电时智能充电机始终与BMS保持通信联系,以保证电池组安全快速充电。车辆最高车速可达117km/h,0~50km/h加速时间为6·80s,50~80km/h加速时间为7·34s,爬坡度超过20%,续驶里程为204km,百公里耗电仅为19kWh。到目前为止该车辆已运行5万多km。     

锂离子电池电极材料的研究进展

综述了国内近年来锂离子电池的正极和负极材料的研究进展，对正极材料中LICoO2，LiNiO2和LiMnO4，负极材料中的碳素和非碳素材料以及合金等的研究现状及发展趋势分别作了评述.。     

锰酸锂正极锂离子二次电池纯电动汽车的研制

以100Ah的锰酸锂锂离子二次电池锂离子电池组和30kW交流电机组成了动力系统,研制了MGL6486EV电动汽车。电池组的电压为304V,能量为37kWh,电池组采用了智能管理系统（BMS）和均衡系统。电动机采用全数字适量控制,并具有刹车能量回收和防溜车功能。在充电时智能充电机始终与BMS保持通信联系,以保证电池组安全快速充电。车辆最高车速可达117km/h,0～50km/h加速时间为6.80s,50～80km/h加速时间为7.34s,爬坡度超过20%,续驶里程为204km,百公里耗电仅为19kWh。到目前为止该车辆已运行5万多km。     

电动自行车用锂离子电池保护板的设计

本文根据电动自行车用锂离子电池保护板的特殊要求设计了一种锂离子电池保护板，实现了对大容量锂离子电池的充、放电保护。     

Synthesis characterization and improved electrochemical performance of Li_2FeSiO_4/C as cathode for lithium-ion battery by metal doping

In this paper, Li_2FeSi_(0.98)M_(0.02)O_4/C(M = Mg, Zn, Co, Mn, Ni) was synthesized as cathode material for lithium ion battery by solid-state method. The results show that the materials doped with Mg and Zn at the Si-sites have good initial discharge capacity. Then Li_2FeSi_(1-x)M_xO_4/C(M = Mg, Zn; x = 0.01, 0.02, 0.03, 0.05) were also synthesized via solid-state method. It is concluded that Li_2FeSi_(0.99)Mg_(0.01)O_4/C and Li_2FeSi_(0.98)Zn_(0.02)O_4/C have better initial discharge capacity which is 125 mAh/g and 166.2 mAh/g, respectively. The capacity of Li_2Fe_(0.98)Zn_(0.02)SiO_4/C is 157.3 m Ah/g after 10 cycles at 0.1 C, and the capacity retention rate is 94.6%. The Li~+ diffusion coefficient of Li_2FeSi_(0.98)Zn_(0.02)O_4/C is higher than that of pure phase materials by one order of magnitude. The Li_2FeSi_(0.99)Mg_(0.01)O_4/C and Li_2FeSi_(0.98)Zn_(0.02)O_4/C were tested by XRD and SEM. XRD patterns indicate that the crystal structure of Li_2FeSiO_4 is not changed after being doped with metal ion at the Si-site. The SEM image indicates that no obvious agglomeration is detected in these materials. Li_2FeSi_(0.98)Zn_(0.02)O_4/C processes better electrochemical performance analyzed by EDS、XPS and FT-IR spectra. The data prove that Si~(4+) is successfully replaced by Zn~(2+) in the crystal structure of Li_2FeSiO_4.     

基于GA-RBF网络的磷酸铁锂电池SOC预测研究

针对动力电池荷电状态(state of charge,SOC)的精确预测问题,提出了一种基于遗传算法的径向基函数(genetic algorithm-radial basis function,GA-RBF)神经网络的磷酸铁锂电池SOC预测方法,它克服了网络参数选择的随机性,具有更强的适应能力。通过仿真实验,证明了该方法比传统的径向基函数(radial basis function,RBF)神经网络预测结果更加准确,运行更稳定,满足电池管理系统对磷酸铁锂(LiFePO4)动力电池SOC预测的精度和实际使用的要求。     

一种基于DSP的锂离子电池管理系统的设计与应用

设计了一种基于DSP的锂离子电池管理系统,以DSP为核心处理器,设计了采样电路、通讯接口、控制接口等。能够实现单体电池电压、总电压、电流、温度的检测,具有SOC估算、通讯、计算机监测等功能,该电池管理系统结构简单,使用方便,能够很好的满足实际使用的需要。     

Low temperature synthesis of NiO/Co3O4 composite nanosheets as high performance Li-ion battery anode materials

NiO/Co3O4 composite nanosheets have been synthesized via a facile method at low temperature for the first time.The as prepared materials were characterized by X-ray powder diffraction(XRD) and transmission electron microscopy(TEM),and the performance of Li-ion batteries(LIBs) as anode materials were also studied.By controlling the atom ratio of Ni:Co,not only the size of the nanosheets can be controlled,the electrode’s conductivity and stability could also be greatly improved.The composite material showed a stable capacity retention during cycling(87% of the second capacity was retained after 15 cycles) even at a relatively large current rate(400 mA/g).The NiO/Co3O4 nanosheet might be promising candidate anode materials in high performance Li-ion batteries.     

Crystal and electronic structure study of the Li_2Mn_(1-x)Nd_xO_3 battery cathode

Neodymium substituted Li_2MnO_3 samples were prepared by the solid-state reaction method. The crystal and electronic structure properties of the prepared samples were investigated by x-ray based techniques. According to the analysis, it was determined that Nd atoms did not sit in to the Cr coordinations in Nd substituted samples and built up a different crystal structure. To support the analysis of the crystal structure study of the samples,electronic structure properties of the Nd substituted samples were studied via the collected data by x-ray absorption fine structure(XAFS) spectroscopy from the Mn K-edge. The results of the data analysis revealed that due to the misfit with the ionic radii and also the oxidation states, substituted neodymium atoms built up isolated crystal domains in Li_8Mn_5Nd_(18) O_(39) cubic crystal structure. The symmetry in Mn K-edge absorption data of the sample both in parent Li_2MnO_3 and Nd substituted samples confirmed that Mn coordinations has not been influenced by the Nd substitution.     

液相法制备锂离子电池负极材料Li4Ti5O12

Li4Ti5O12负极材料因其在充放电过程中"零应变"的优势,得到了广泛关注,成为锂离子电池负极材料的研究热点.采用液相法制备了Li4Ti5O12负极材料.通过正交实验,确定了Li4Ti5O12的最佳制备工艺条件:烧结温度为750℃;烧结时间为8 h;LiOH.H2O为锂源;原料中锂钛的物质的量比为0.85.该条件下制备的材料具有较好的电化学性能,首次放电比容量可达到191.61 mAh/g.     

Li4Ti5O12材料的固相法制备及其煅烧温度

以Li₂CO₃,TiO₂为原料,无水乙醇为分散剂,采用高温固相法,通过两步煅烧方式制备出不同煅烧温度下的Li₄Ti₅O₁₂粉末材料.采用X射线衍射（XRD）、扫描电镜（SEM）表征材料的结构和形貌,采用恒电流充放电、交流阻抗和循环伏安等方法测试材料电化学性能.结果表明：在800 ℃下煅烧6 h后可得到晶型完整的纯相Li₄Ti₅O₁₂,其颗粒均匀分布在200~400 nm.Li₄Ti₅O₁₂在0.5C倍率下首次可逆比容量为157.67 mA·h/g,库伦效率为96.1%,经过100次循环充放电后容量保持率为98.63%;在5C倍率下首次可逆比容量为107.0 mA·h/g,经过1 000次循环充放电后容量保持率为84.1%.     

Zr掺杂对Li4Ti5O12电化学性能的影响

采用高温固相法合成了掺锆锂钛氧复合氧化物作为锂离子电池负极材料,并对材料进行了X射线衍射分析、电化学阻抗测试、循环伏安测试及恒电流充放电测试,锆的掺杂并未改变材料的晶体结构,但降低了材料的规整度,实验结果表明：锆的掺杂在一定程度上改善了锂钛氧化合物的电化学性能,降低了电极极化,在电极表面未形成钝化膜,其中以掺杂比为Li：Ti=1：10（原子比）的材料性能最好,首次放电比容量可达到167,5mAh·g^-1,经过50次循环后,放电容量仍保持在146,9mAh·g^-1,     

纯化前后天然石墨的电化学嵌/脱锂性能

研究了天然石墨的纯化工艺和纯化前后天然石墨的电化学嵌/脱锂性能.研究结果表明,采用酸浸与加碱烧结相结合纯化工艺可以得到含碳量达99%的纯化石墨,且采用该工艺没有改变石墨的微观结构;与未纯化的石墨相比,纯化石墨的第1次循环效率明显提高,第1次不可逆容量较大幅度降低;纯化前、后的微晶石墨嵌/脱锂电化学性能均比鳞片石墨的嵌/脱锂电化学性能差,这主要是由于2种石墨存在结构差异.     

正极材料尖晶石LiMn2O4掺杂Ce6+的合成与性能研究

由高温固相法合成了锂离子电池正极材料尖晶石LiCexMn2-xO4(x=0～0.5),并经XRD和电化学等测试。实验结果表明,材料LiCe0.03Mn1.97O4在常温和高温下都具有较好的循环性能和电化学性能。     

LiFe1-x Mgx PO4/C的制备和性能研究

以乙酸镁为掺杂元素、蔗糖为碳源,采用固相反应法制备镁掺杂磷酸铁锂包覆碳复合材料LiFe1-xMgxPO4/C(x=0.01,0.02,0.03,0.04).利用X射线衍射(XRD)分析其结构,扫描电镜(SEM)观察其形貌,恒电流法测定其电化学性能.研究结果表明镁离子掺杂没有影响材料的结构,而是提高了其放电容量和循环性能.在这些样品中,LiFe0.98Mg0.02位PO4/C的容量最高,首次放电达到140.0 mAh/g;并且在80次循环后容量没有衰减反而增加到148.6 mAh/g左右.     

In Situ XRD and XAS Investigation of Cathode Materials in Li-ion Battery

1 Results Lithium ion batteries have been widely used in modern portable electronics,such as cellular phones and notebook computers,because of their low cost,long life,and high energy density.In the lithium ion batteries,the cathode provides lithium ion source and plays a critical role to determinate the performance of battery.Lithium transition metal oxides have been investigated as active cathode materials due to their high potential versus Li/Li and large proportion of the lithium ions can be insert...     

以球形Li3P0O4制备球形LiFePO4

以曲拉通100作表面活性剂，用超声波法制备了球形度较好、平均粒径为10μm的球形Li3PO4。以球形Li3PO4为前驱体制备了部分球形的LiFePO4，并对其电化学性能进行了研究。由该法制备的LiFePO4振实密度为1．20g／cm^3，较其他方法制备的LiFePO4密度有所提高。