基于DKF的锂电池SOC与内阻估算

电动汽车电池管理系统(BMS)需要满足对电池荷电状态(SOC)进行准确地估算。为提高传统安时法估算SOC的精度,根据二阶RC等效电路模型,提出了双卡尔曼滤波(DKF)来完成对电池SOC及其欧姆内阻R0联合在线估算的算法。通过进行某型号三元锂电池的复合脉冲功率特性测试(HPPC)实验及放电实验等,离线拟合得到所需模型参数。将Matlab仿真结果与同等条件下的实验结果进行对比分析,证明了DKF算法能够有效地在线估算电池SOC及其欧姆内阻R0,且误差在3%以内。最后,证明了DKF算法能够比安时法更好地估算出各点处的SOC值。     

磷酸铁锂电池模型参数辨识与SOC估算

根据磷酸铁锂电池的特性,从电池电化学角度分析,建立电池的等效电路模型。通过实验方法测得电池开路电压与SOC关系和电池模型的参数,利用卡尔曼滤波法来估算电池初始荷电状态（SOC_0）.实验与仿真表明,该算法可以有效的估算出SOC初始值,并可以将误差控制在10%之内.     

基于交流注入法和有效值转换的航空蓄电池内阻检测方法

介绍了一种基于交流注入法和有效值转换的蓄电池内阻检测方法,设计一种由滤通放大电路和有效值转换电路组成的蓄电池内阻检测电路,并通过Multisim和实验证明了该设计的可行性.     

面向全生命周期的锂电池健康状态估计

为研究锂电池在动态工况下以及全生命周期内健康状态的准确估计问题,提出一种基于固定充电电压片段的方法.选取充电过程中某固定电压片段内所充电量作为电池容量估算的等效健康因子,利用遗传算法选择最优的充电电压片段,在两类锂电池老化实验数据的基础上,设计放电电流不同、健康状态区间不同的8个验证算例.实验结果表明:8个验证算例中,训练集电池和测试集电池健康状态估计的平均绝对误差与均方根误差均低于1.55%;所提出的基于等效健康因子的方法,在100%～60%的全寿命健康状态区间,对于不同的放电电流、不同材料的电池,均能进行健康状态的准确在线估计,具有较强的适用性.     

基于交流阻抗谱的锂离子电池老化模式量化方法

针对锂离子电池老化实验过程中交流阻抗谱呈现2种不同变化趋势的现象,加入了双等效电路模型分析的思路,设计了一种能适用于2种交流阻抗谱特性的老化模式量化方法 .根据这种老化模式量化方法,进行不同条件的电池老化实验,并研究了3种老化模式的变化趋势,指出一个适用于本实验电池的多种老化条件下的统一规律:活性锂离子损失和活性材料损失在老化过程中影响比较明显,其中活性材料损失影响最为明显,与活性材料损失相比,电导率损失与活性锂离子损失在老化过程中的影响较弱.     

一种铅酸蓄电池容量快速检测方法的研究

铅酸蓄电池容量快速检测是当前铅酸蓄电池研究的重点内容之一,文中在介绍铅酸蓄电池容量已有检测方法的基础上,通过详细的理论推导,给出了一种可以快速检测铅酸蓄电池容量的方法,说明了应用这种检测方法的原理样机的设计要点,并用36A·h,60A·h,100A·h,150A·h,200A·h五种不同标称容量、不同健康状态的铅酸蓄电池进行了试验。试验结果表明这种快速检测方法是可行的,为铅酸蓄电池容量快速检测提供了一种有效的参考方法,但如何使这种检测方法适用于更多类型和健康状态的铅酸蓄电池,还需要进一步研究。     

基于动力锂离子电池健康状态的全寿命周期优化充电策略

针对目前采用经验充电电流值的恒流恒压(CC-CV)充电策略导致电池老化严重的问题,提出一种优化充电策略。从电池整个寿命周期角度出发,基于锂离子电池容量衰退模型,以电池最小衰退容量为目标,采用数据库动态规划(DDP)对电池寿命周期进行规划,得到不同循环阶段下对应寻优充电电流分布,并分析充电电流对电池容量衰退的影响。最后,在Matlab/Simulink中与现有恒流恒压充电策略进行仿真分析对比,结果表明,该策略能够有效延长电池循环寿命。     

基于改进布谷鸟算法的快速充电方法

针对锂离子电池快速充电问题,提出了一种基于改进布谷鸟算法的快速充电方法。首先建立锂离子电池等效电路模型和热模型,然后以充电时间和温升为优化目标,采用多阶充电的方法,最后用改进布谷鸟算法搜索每个阶段的充电电流。讨论了充电时间和温升的权重系数对电池充电性能的影响,与传统布谷鸟算法相比,优化布谷鸟算法充电方法能够在温度升高几乎相同的情况下,充电时间减少约5%左右,平衡了充电速度和温升,延长了锂离子电池的使用寿命。     

锂离子电池用磷腈类聚合物电解质的制备与性能

采用六氯环三磷腈高温开环聚合方法制备了聚二氯磷腈,然后采用醇钠法,取代聚二氯磷腈的氯,制备了聚二（二乙二醇单甲醚）磷腈（MEEP）,探索出了较佳的合成工艺,采用FT-IR、31P-NMR、13C-NMR、质谱对其进行了结构表征和分析。结果表明,所制备的磷腈聚合物确实为MEEP。采用自制的MEEP,与三氟甲基磺酸锂（LiCF3SO3）盐进行复配,制备了锂离子电池用聚合物固体电解质,对其热稳定性、导电性进行了测试,其开始分解温度在200℃以上,室温电导率达到了1.187×10-4S/cm（25℃）,具有较佳的导电性和热稳定性,可用于锂离子电池的电解质。     

锂离子电池正极材料LiMgxMn2-xO4的合成及性能

利用相转移法合成了LiMgxMn2-xO4前驱体,在电炉中于一定温度下烧结一定时间,得到锂离子电池正极材料粉体,并利用XRD、SEM、IR等对材料粉体进行结构形态表征.考察焙烧温度、焙烧时间、Mg的掺杂含量等对产物结构和电化学性能的影响.实验结果表明:当Mg的掺杂量x=0.06,于750℃焙烧15 h时所制备的样品材料结构稳定且呈尖晶石型,样品电极的充放电性能良好,首次放电比容量达125 mAh/g,放电平稳,样品电极可逆循环性能良好.     

Preparation of LiFePO4 for lithium ion battery using Fe2P2O7 as precursor

In order to obtain a new precursor for LiFePO4, Fe2P2O7 with high purity was prepared through solid phase reaction at 650 ℃ using starting materials of FeC2O4 and NH4H2PO4 in an argon atmosphere. Using the as-prepared Fe2P2O7, Li2CO3 and glucose as raw materials, pure LiFePO4 and LiFePO4/C composite materials were respectively synthesized by solid state reaction at 700 ℃ in an argon atmosphere. X-ray diffractometry and scanning electron microscopy（SEM） were employed to characterize the as-prepared Fe2P2O7, LiFePO4 and LiFePO4/C. The as-prepared Fe2P2O7 crystallizes in the Cl space group and belongs to β-Fe2P2O7 for crystal phase. The particle size distribution of Fe2P2O7 observed by SEM is 0.4-3.0 μm. During the Li^＋ ion chemical intercalation, radical P2O7^4- is disrupted into two PO4^3- ions in the presence of O^2-, thus providing a feasible technique to dispose this poor dissolvable pyrophosphate. LiFePO4/C composite exhibits initial charge and discharge capacities of 154 and 132 mA·h/g, respectively.     

Nano-sized Sn/MWNTs and MWNTs Served as the Anode of Lithium Ion Battery

A chemical deposition was supposed to be an effwient method in preparation of nano-sized Sn/ MWNTs. The nanoconmposites of MWNTs and Sn/ MWNTs were both used as anodes of lithium ion battery. The special capacities and coulomb efficiencies of Snl MWNTs were studied by means of electrochemical methods. The coating of Sn on MWNTs observed by TEM was amorphous and nano-sized. The reversible capacity of Sn/ MWNTs , which was much larger than that of MWNTs , was 824 mAh/ g in the 1 st charge and discharge cycle. The coulomb efficiency of Sn/ MWNTs in the 1 st cycle was increased by 16% compared with that of MWNTs. The additional Sn, which was 37wt% of total Sn/ MWNTs＇ weight, introduced the additional reversible lithiation capacity at least 250 mAh/ g in the 40 charge and discharge cycles. The dispersing degree of Sn on MWNTs was the main reason for the influence of the electrochemical perfomance of the Sn/ MWNTs . Sn/ MWNTs is proved to be a promising candidate as an anode of lithium ion battery.     

Effects of different iron sources on the performance of LiFePO4/C composite cathode materials

Olivine LiFePO₄/C composite cathode materials were synthesized by a solid state method in N₂ + 5vol% H₂ atmosphere. The effects of different iron sources, including Fe(OH)₃ and FeC₂O₄·2H₂O, on the performance of as-synthesized cathode materials were investigated and the causes were also analyzed. The crystal structure, the morphology, and the electrochemical performance of the prepared samples were characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM), laser particle-size distribution measurement, and other electrochemical techniques. The results demonstrate that the LiFePO₄/C materials obtained from Fe(OH)₃ at 800°C and FeC₂O₄·2H₂O at 700°C have the similar electrochemical performances. The initial discharge capacities of LiFePO₄/C synthesized from Fe(OH)₃ and FeC₂O₄·2H₂O are 134.5 mAh·g⁻¹ and 137.4 mAh·g⁻¹ at the C/5 rate, respectively. However, the tap density of the LiFePO₄/C materials obtained from Fe(OH)₃ are higher, which is significant for the improvement of the capacity of the battery.     

高岭土掺杂NASICON固体电解质及全固态电池性能

针对LiTi2(PO4)3基固态电解质电导率低的问题,采用浙江三门高岭土矿作为主要原料,以高温固相法制备铝、镁、硅共掺杂钠超离子导体(NASICON)型快离子导体Li1+2x+2yAlxMgyTi2-x-ySixP3-xO12.研究掺杂比例、温度对固态电解质离子电导率的影响.结果表明,组成为Li1.8Al0.1Mg0.3Ti1.6Si0.1P2.9O12固体电解质在423 K时有最高离子电导率7.86×10-4 S·cm-1.以该组成固态电解质为基片,喷雾热解原位制备Al/ Li1+xV3O8/ Li1.8Al0.1Mg0.3Ti1.6Si0.1 P2.9O12 /C全固态电池并在1.8～3.9 V电压区间进行50次充放电测试.该电池具有较好的稳定性及循环容量保持能力.30次循环以后放电容量基本稳定在190～205 mAh·g-1之间,充放电效率大于90%.     

多孔碳包覆硅微球于锂离子电池负极中的应用

为了缓解纯硅负极材料在充放电过程中带来的巨大体积效应并降低电解质与电极之间的副反应程度,提出了一种简单高效的硅碳复合材料合成方法.以P123为分散剂、葡萄糖为碳源,利用水热法制备P-Si/C复合材料.结果表明,制备得到的复合材料可以极大地缓解充放电过程中产生的体积效应.当复合材料作为锂电池负极时,其首次放电比容量为1 800 mA·h/g,在500 mA/g电流密度下经100次循环后,其放电比容量能够稳定维持为521 mA·h/g,呈现出良好的循环性能.     

Microwave Synthesis of Cathode Material LixMn2O4 for Lithium-ion Battery

LixMn2O4 was synthesized rapidly by microwa heaing,the product phases of the microwave synthesis and comventional solid-solid-state synthesis were comparatively inesitigated,The capacity of microwave synthesis product decreases relatively slow,The lithium ion can be inserted into and extracted from the spinel framework structure fluently after cycling .But the capacity of the conventional solid-state synthesis product is more remarkably lowered.The spinel framework structure was destroyed which hindered the lithium ion from inserting and extracting,Tehe influential factors of the process parameters are discussed such as heat preservation time,pre-heating at 400℃ for 24 h and coupled agent.     

锂离子电池正极材料LiFePO4的合成及其改性

采用共沉淀法合成了锂离子正极材料LiFePO4,考察了不同合成条件对材料结构及性能的影响.研究结果表明:通过碳包覆改性后,LiFePO4的容量可明显提高,SiO2的掺杂对LiFePO4的结构没有影响.同时讨论了上述两种改性方法对材料性能的影响机制.     

Synthesis and characterization of triclinic structural LiVPO4F as possible 4.2 V cathode materials for lithium ion batteries

A potential 4.2 V cathode material LiVPO4F for lithium batteries was prepared by two-step reaction method based on a carbon-thermal reduction （CTR） process. Firstly, V2O5, NH4H2PO4 and acetylene black are reacted under an Ar atmosphere to yield VPO4. The transition-metal reduction is facilitated by the CTR based on C→CO transition. These CTR conditions favor stabilization of the vanadium as V^3＋ as well as leaving residual carbon, which is useful in the subsequent electrode processing. Secondly, VPO4 reacts with ElF to yield LiVPO4F product. The property of the LiVPO4F was investigated by X-ray diffractometry （XRD）, scanning electron microscopy （SEM） and electrochemical measurement. XRD studies show that LiVPO4F synthesized has triclinic structure（space group p I ）, isostructural with the naturally occurring mineral tavorite, EiFePO4-OH. SEM image exhibits that the particle size is about 2μm together with homogenous distribution. Electrochemical test shows that the initial discharge capacity of LiVPO4F powder is 119 mA·h/g at the rate of 0.2C with an average discharge voltage of 4.2V （vs Ei/Li^＋）, and the capacity retains 89 mA·h/g after 30 cycles.