锂氧电池LATP固态电解质的制备及性能

采用Pechini法制备了钠超离子导体(NASCION)型Li1.4Al0.4Ti1.6(PO4)3(LATP)固态电解质,并将其应用于锂氧电池。通过XRD以及SEM表征了LATP的结构及形貌。结果显示:所制备的LATP电解质晶粒粒径均匀,致密度高。使用电化学阻抗谱评价了LATP固态电解质的离子电导率,并通过充放电测试考察了使用固态电解质的锂氧电池的充放电性能。结果表明:所制备的LATP具有较高的锂离子电导率,30℃时LATP的离子电导率为1.1×10–4 S/cm;LATP可以有效地降低锂氧电池在放电及充电过程中的副反应,提高锂氧电池的充放电循环性能。     

应用于锂离子电池的无机晶态固体电解质导电性能研究进展

固体电解质是电解质材料的一个重要种类,利用固体电解质组装全固态电池是解决锂离子电池安全性差,能量密度低等问题的有效方法。围绕着几类重要的无机晶态固体电解质,包括：钙钛矿型、钠快离子导体型(NASICON)、锂快离子导体型(LISICON)、硫代–锂快离子导体型(thio-LISICON)、石榴石型,对晶体结构、合成工艺及其与电极材料匹配性能的研究进展进行综述,并着重讨论了无机晶态固体电解质应用于锂离子电池的导电机理以及提高离子电导率的原则与方法。     

锂电池固态电解质新材料问世

近日,丰田中央研发实验室开发了一种有望用于高功率和高能量的全固态锂离子电池的固体电解质新材料。该材料用于正极为钴酸锂、负极为锂单质的锂离子电池时,具有优异的充放电性能和循环性能。全固态锂离子电池以传统固体氧化物作电解质时,比有机电解液和固体硫化物中的离子电导率低很多。该电解质不仅有高的化学稳定性和宽的电化学窗口,而且在室温下的离子电导率比有机电解液的电导率还高出两个数量级。该固体电解质与正极不会发生副反应和材料剥离,且界面阻抗能低到和普通的液态锂离子电池接近,但界面阻抗的活化能小很多。     

锂电池固态电解质新材料问世

近日,丰田中央研发实验室开发了一种有望用于高功率和高能量的全固态锂离子电池的固体电解质新材料。该材料用于正极为钴酸锂、负极为锂单质的锂离子电池时,具有优异的充放电性能和循环性能。     

有机硅氧烷改性水性聚氨酯基聚合物电解质及全固态锂离子电池

以聚乙二醇(PEG)、有机硅氧烷(OFX)、异佛尔酮二异氰酸酯(IPDI)为主要原料,制备了一系列水性聚氨酯,并与双(三氟甲基磺酰)亚胺锂(Li TFSI)复合,得到一系列全固态聚合物薄膜。通过拉伸性能测试、红外光谱、热重分析和电导率测试等研究了其结构与性能的关系。将制备的聚合物电解质膜用于全固态锂离子电池的组装,测试了电池的性能。结果表明:适量引入有机硅氧烷可改善聚合物电解质膜的力学性能和电化学性能;当PEG与有机硅氧烷质量比为3:1时聚合物电解质膜的综合性能最佳,80℃时电导率为6.24×10~(–4)S/cm;以磷酸铁锂为正极制备的全固态锂离子电池在0.2C电流80℃时放出131 mA·h/g的比容量。     

固态聚合物电解质性能提升方法的研究进展

商用锂离子电池由于使用危险和易燃的液体电解质,容易发生火灾和泄漏问题,存在安全隐患。全固态锂离子电池由于其安全性和潜在的高能量密度优势,被认为是下一代能量存储设备。固态聚合物电解质作为全固态锂电池的关键部件,具有良好的不可燃性和对锂金属阳极的适应性,近年来受到广泛关注。但其离子导电性低、力学性能差以及循环寿命不足等限制了其实际应用。根据近年来的研究进展,本文总结了优化固态聚合物电解质性能的方法,包括增加离子电导率,提高电压稳定性、抑制枝晶形成、增加离子选择性和降低界面电阻等,并简要分析了聚合物电解质的现状和发展前景,为固体聚合物电解质基电池的广泛应用奠定了基础。     

锂磷酸盐微晶玻璃固体电解质材料研究进展

锂磷酸盐微晶玻璃固体电解质具有合成简单,电化学稳定性高等优点,已经对其进行了大量的研究工作。结合近几年的研究,分别综述了三元、四元和五元3种不同系统的锂磷酸盐微晶玻璃固体电解质所具有的最大电导率。并描述了Nasicon结构的快离子导体和交流阻抗谱在计算电导率上的应用。锂磷酸盐微晶玻璃固体电解质在全固态锂离子电池中将会有更广泛的应用。     

石榴石型固体电解质体系：离子输运性能调控及其全固态电池研究进展

全固态锂电池采用固体电解质取代液态电解质,使其具有更高安全性,且有望进 一步提高电池的能量密度。而在众多固体电解质中,具有石榴石型结构的立方相 Li7La3Zr2O12 (LLZO) 及其元素掺杂产物由于室温离子电导率较高、电化学窗口较宽、与锂金属稳定等优点, 最有可能应用于全固态锂电池中。本文对 LLZO 的物相及晶体结构、制备方法、锂离子电导率 的提升策略以及其所组装的全固态锂电池等方面进行了详细介绍,并预测了 LLZO 固体电解质 材料进一步提升锂离子电导率的潜在可能以及 LLZO 所装配的全固态锂电池的发展方向。     

钙钛矿型固体锂离子电解质的研究进展

锂离子电池广泛用于便携式电子设备,例如电脑、手机和电动车辆。目前使用的电解质是有机液体材料,但存在易燃且易挥发的安全问题。无机固体锂离子电解质具有能量密度高、使用寿命长、功率大、安全性高、无污染等优点。似乎无机固体锂离子电解质是传统有机液体电解质的良好替代品。其中,钙钛矿型锂离子电解质具有高的晶粒导电性和良好的化学稳定性,在全固态锂离子电池中显示出巨大的潜在应用。综述了近年来钙钛矿型锂离子电解质的晶体结构,制备工艺和掺杂改性的研究进展。目前,大多数制备LLTO(锂镧钛氧)的方法需要更高的温度和更长的时间,并且LLTO本身的晶体电阻更大。因此,如何降低晶界电阻,提高离子电导率,寻找中低温制备工艺仍是未来研究的重点。     

SOFC氧离子导体电解质材料的研究进展及性能优化策略

典型的固体氧化物燃料电池(SOFC)由致密电解质、多孔阴极和阳极三部分构成。其中,电解质介于阴极和阳极之间,是一种具有全固态结构的氧化物陶瓷材料。电解质是SOFC的核心部件之一,是电池工作温度和电池性能的决定性因素。目前,对于高温电解质材料的研究与应用已经相对成熟。但是,在电池高温运行条件下,会导致电极和电解质界面反应、密封困难及使用寿命变短等问题。因此,SOFC电解质的发展逐渐趋向于中温化。但随着工作温度的降低,电解质欧姆阻抗(Ro)势必增大,使得电池的电导率下降。基于此,电解质在中温下的性能提升以及优化近年来备受关注。文中综述了几种不同类型的氧离子导体电解质最新研究进展,并论述了SOFC中低温运行条件下电解质性能提升的主要优化策略。     

A design of Nafion-coated bilayered quasi-solid electrolyte for lithium-O2 batteries with high performance

Lithium-air(also known as lithium-oxygen) batteries have attracted considerable global attention in recent years due to their extremely high energy density(11,140 W·h·kg~(-1)).The electrolyte is a key element in lithium-air batteries and the traditional organic electrolyte has great safety risk due to leakage.On the contrary,the polymer electrolyte has the advantages of high safety,high stability and easy processing comparing with the organic liquid electrolytes.In this paper,a new idea was proposed to coat the Nafion membrane on a layer of polymer for blocking the oxidation reduction electric(RM) and Li based on the selective permeability on lithium ion of the Nafion membrane.Self-made thicknesscontrollable Nafion membrane,polyvinylidene fluoride-hexafluoropropylene copolymer(PVDF-HFP)and 2,2,6,6-tetramethylpiperidinooxy(TEMPO) were used to prepare a quasi solid polymer electrolyte(NSPE).Electrochemical workstation and LAND battery testing system were used to perform a galvanostatic charge/discharge test on Li-O_2.The ionic conductivity of NSPE was 4.3 × 10~(-4) S·cm~(-1) at room temperature and the discharge platform was 2.6 V and the charging voltage was 3.7 V after 50 cycles with the cut-off capacity of 500 mA·h·g~(-1).     

Fabrication and characterization of LATP/PAN composite fiber-based lithium-ion battery separators

Lithium aluminum titanium phosphate (LATP)/polyacrylonitrile (PAN) composite fiber-based membranes were prepared by electrospinning dispersions of LATP particles in PAN solutions. The electrolyte uptakes of the electrospun LATP/PAN composite fiber-based membranes were measured and the results showed that the electrolyte uptake increased as the LATP content increased. The lithium ion conductivity, the electrochemical oxidation limit and the interface resistance of liquid electrolyte-soaked electrospun LATP/PAN composite fiber-based membranes were also measured and it was found that as the LATP content increased, the electrospun LATP/PAN composite fiber-based membranes had higher lithium ion conductivity, better electrochemical stability, and lower interfacial resistance with lithium electrode. Additionally, lithium//1 M LiPF₆/EC/EMC//lithium iron phosphate cells using LATP/PAN composite fiber-based membranes as the separator demonstrated high charge/discharge capacity and good cycle performance.     

湿化学法制备石榴石型固态电解质Li7La3Zr2O12

锂电池因能量密度高、循环寿命长、绿色清洁等特点被广泛应用,但其液态电解质易泄漏、挥发,且隔膜易被锂枝晶刺穿造成短路,引发危险。固态电解质大多是不具燃烧性的无机材料,室温下离子电导率较高、电化学窗口宽且适用温度范围广。因此,采用固态电解质替代液态电解质具有十分重要的意义。相对于其他类型固态电解质,石榴石型氧化物Li₇La₃Zr₂O₁₂（LLZO）具有离子电导率高、电化学窗口宽（>5V vs. Li/Li⁺）、对锂稳定性好和热稳定性高等特点,是非常具有发展潜力的无机固态电解质。本文采用溶胶-凝胶法和低温燃烧法两种湿化学法合成LLZO粉末,对应的电解质片在40℃时的离子电导率分别为1.22×10^-5S/cm和3.87×10^-6S/cm,活化能分别为0.34eV和0.32eV。从实验结果综合比较,溶胶-凝胶法为最佳制备方法。     

1-Alkyl-2,3-dimethylimidazolium bis(trifluoromethanesulfonyl)imide ionic liquids as highly safe electrolyte for Li/LiFePO4 battery

Several 1-alkyl-2,3-dimethylimidazolium bis(trifluoromethanesulfonyl)imide ionic liquids (alkyl-DMimTFSI) were prepared by changing carbon chain lengths and configuration of the alkyl group, and their electrochemical properties and compatibility with Li/LiFePO₄ battery electrodes were investigated in detail. Experiments indicated the type of ionic liquid has a wide electrochemical window (−0.16 to 5.2 V vs. Li⁺/Li) and are theoretically feasible as an electrolyte for batteries with metallic lithium as anode. Addition of vinylene carbonate (VC) improves the compatibility of alkyl-DMimTFSI-based electrolytes towards lithium anode and LiFePO₄ cathode, and enhanced the formation of solid electrolyte interface to protect lithium anodes from corrosion. The electrochemical properties of the ionic liquids obviously depend on carbon chain length and configuration of the alkyl, including ionic conductivity, viscosity, and charge/discharge capacity etc. Among five alkyl-DMimTFSI-LiTFSI-VC electrolytes, Li/LiFePO₄ battery with the electrolyte-based on amyl-DMimTFSI shows best charge/discharge capacity and reversibility due to relatively high conductivity and low viscosity, its initial discharge capacity is about 152.6 mAh g⁻¹, which the value is near to theoretical specific capacity (170 mAh g⁻¹). Although the battery with electrolyte-based isooctyl-DMimTFSI has lowest initial discharge capacity (8.1 mAh g⁻¹) due to relatively poor conductivity and high viscosity, the value will be dramatically added to 129.6 mAh g⁻¹ when 10% propylene carbonate was introduced into the ternary electrolyte as diluent. These results clearly indicates this type of ionic liquids have fine application prospect for lithium batteries as highly safety electrolytes in the future.     

离子液体电解质在锂二次电池中的应用

锂二次电池作为动力电池,被寄予厚望。但锂二次电池面临的安全隐患也是不容忽视的,是当前亟需解决的问题,而这与电解质的性质有着紧密的联系。离子液体由于具有较宽电化学窗口、良好的导电性、高热稳定性、几乎无挥发及不燃烧等优良的特性,正在作为一种新型绿色替代溶剂被电化学领域所关注。离子液体的不燃烧特性,对于替代传统有机电解质具有十分重要的意义。本文阐述了新型溶剂“离子液体”作为电解质在锂二次电池中的应用,其中重点阐述了在碳、硅、钛酸锂(Li₄Ti₅O₁₂)、磷酸亚铁锂(LiFePO₄)、钴酸锂LiCoO₂、镍锰酸锂(LiNi_xMn_yO_z),镍钴锰锂(LiNi_xCo_yMn_zO_w)及在锂硫(Li-S)电池中的应用。     

全固态锂离子电池硫化物电解质的研究进展

目前,锂离子电池已经广泛地应用于交通、通讯、便携式电子产品及电动工具等领域。传统的锂离子电池采用液体电解液,存在易挥发、易泄漏、抗冲击性能差等缺点,存在安全隐患。全固态电解质具有热稳定性高、循环寿命长、抗震动性能好等优点,是锂离子电池取代液体电解液的一种理想替代方案。硫化物电解质体系具有离子导电率高、制备简便、电化学窗口宽等优点,已经成为全固态锂离子电池的研究热点。综述了全固态锂电池Li₂S-P₂S₅基电解质的最新研究进展,总结了各种性能改进方法,并对其应用前景做了展望。     

Effect of SnO–P2O5–MgO glass addition on the ionic conductivity of Li1.3Al0.3Ti1.7(PO4)3 solid electrolyte

NASICON-type structured compounds Li_1+xM_xTi_2-x(PO₄)₃ (M = Al, Fe, Y, etc.) have captured much attention due to their air stability, wide electrochemical window and high lithium ion conductivity. Especially, Li_1.3Al_0.3Ti_1.7(PO₄)₃ (LATP) is a potential solid electrolyte due to its high ionic conductivity. However, its actual density usually has a certain gap with the theoretical density, leading the poor ionic conductivity of LATP. Herein, LATP solid electrolyte with series of SnO–P₂O₅–MgO (SPM, 0.4 wt%, 0.7 wt%, 1.0 wt%, 1.3 wt%) glass addition was successfully synthesized to improve the density and ionic conductivity. The SPM addition change Al/Ti–O bond and P–O bond distances, leading to gradual shrinkage of octahedral AlO₆ and tetrahedral PO₄. The bulk conductivity of the samples increases gradually with SPM glass addition from 0.4 wt% to 1.3 wt%. Both SPM and the second-phase LiTiPO₅, caused by glass addition, are conducive to the improvement of compactness. The relative density of LATP samples increases first from 0 wt% to 0.7 wt%, and then decreases from 0.7 wt% to 1.3 wt% with SPM glass addition. The grain boundary conductivity also changes accordingly. Especially, the highest ionic conductivity of 2.45 × 10^?4 S cm^?1, and a relative density of 96.72% with a low activation energy of 0.34 eV is obtained in LATP with 0.7 wt% SPM. Increasing the density of LATP solid electrolyte is crucial to improve the ionic conductivity of electrolytes and SPM glass addition can promote the development of dense oxide ceramic electrolytes.     

Li+电池固态聚合物电解质研究进展

固态聚合物电解质具有高安全性、高成膜性和黏弹性等优点,并与电极具有良好的接触性和相容性,是实现高安全性和高能量密度固态Li⁺电池的重要电解质体系。然而聚合物电解质室温离子电导率较低（10^-8~10^-6 S·cm^-1）,不能满足固态聚合物电池在常温运行的需求。因此,在提高离子电导率、机械强度和电化学稳定性等本征属性的基础上,同时探究改善电解质/电极的界面处及电极内部的离子输运是研发固态聚合物Li⁺电池面临的关键问题。主要从改性聚合物电解质用以提高Li⁺电池电化学性能的角度出发,综述了凝胶聚合物电解质、全固态聚合物电解质和复合固态电解质中的离子输运机制及其关键参数,总结了近年来聚合物电解质的最新研究进展和未来的发展方向。     

A high ionic conductive glass fiber-based ceramic electrolyte system for magnesium‒ion battery application

The rechargeable magnesium-ion batteries are one of the emerging alternatives of lithium-ion batteries as it has a high volumetric capacity, non-toxic nature and a divalent charge of Mg-ions. The design of an excellent performing magnesium-ion battery requires a stable electrolyte system with high ionic conductivity. However, there is a lack of understanding of how different materials affect the properties of separators in terms of ionic conductivity and stability. In the present study, an attempt has been made to compare the physical and electrochemical characteristics of glass-ceramic and polypropylene membranes as separators in the magnesium-ion battery, using magnesium bis(trifluoromethanesulfonimide) and propylene carbonate as an organic electrolyte. The characterization like X-ray diffraction, field emission electron microscopy, electrolyte uptake, ionic conductivity, voltage stability, thermal stability and transference number are thoroughly examined for both the membranes. The glass-ceramic electrolyte system showed significantly higher ionic conductivity of 9.22 mS cm⁻¹ at room temperature as compared to the polypropylene membrane. Additionally, the glass-ceramic electrolyte system showed higher thermal and voltage stability.