Overcoming the Na-ion conductivity bottleneck for the cost-competitive chloride solid electrolytes

Chloride solid electrolytes possess multiple advantages for the construction of safe,energy-dense allsolid-state sodium batteries,but presently the chlorides with sufficiently high cost-competitiveness for commercialization almost all exhibit low Na-ion conductivities of around 10^(-5)S cm^(-1)or lower.Here,we report a chloride solid electrolyte,Na_(2.7)ZFCl_(5.3)O_(0.7),which reaches a Na-ion conductivity of 2.29×10^(-4)S cm^(-1)at 25℃without involving overly expensive raw materials such as rare-earth chlorides or Na_(2)S.In addition to the efficient ion transport,Na_(2.7)ZrCl_(5.3)O_(0.7)also shows an excellent deformability surpassing that of the widely studied Na_(3)PS_(4),Na_(3)SbS_(4),and Na_(2)ZrCl_(6)solid electrolytes.The combination of these advantages allows the all-solid-state cell based on Na_(2.7)ZrCl_(5.3)O_(0.7)and NaCrO_(2)to realize stable room-temperature cycling at a much higher specific current than those based on other non-viscoelastic chloride solid electrolytes in literature(120 mA g^(-1)vs.12-55 mA g^(-1));after 100 cycles at such a high rate,the Na_(2.7)ZFCl_(5.3)O_(0.7)-based cell can still deliver a discharge capacity of 80 mAh g^(-1)at25℃.

Polymer dispersed ionic liquid electrolytes with high ionic conductivity for ultrastable solid-state lithium batteries

Solid polymer electrolytes(SPEs)have emerged as one of the most promising candidates for building solid-state lithium batteries due to their excellent flexibility,scalability,and interfacial compatibility with electrodes.However,the low ionic conductivity and poor cyclic stability of SPEs do not meet the requirements for practical applications of lithium batteries.Here,a novel polymer dispersed ionic liquid-based solid polymer electrolyte(PDIL-SPE)is fabricated using the in situ polymerization-induced phase separation(PIPS)method.The as-prepared PDIL-SPE possesses both outstanding ionic conductivity(0.74 mS cm^(-1) at 25℃)and a wide electrochemical window(up to 4.86 V),and the formed unique three-dimensional(3D)co-continuous structure of polymer matrix and ionic liquid in PDIL-SPE can promote the transport of lithium ions.Also,the 3D co-continuous structure of PDIL-SPE effectively accommodates the severe volume expansion for prolonged lithium plating and stripping processes over 1000 h at 0.5 mA cm^(-2) under 25℃.Moreover,the LiFePO_(4)//Li coin cell can work stably over 150 cycles at a 1 C rate under room temperature with a capacity retention of 90.6%from 111.1 to 100.7 mAh g^(-1).The PDIL-SPE composite is a promising material system for enabling the ultrastable operation of solid-state lithium-metal batteries.

Functional additives for solid polymer electrolytes in flexible and high-energy-density solid-state lithium-ion batteries

Solid polymer electrolytes(SPEs)have become increasingly attractive in solid-state lithium-ion batteries(SSLIBs)in recent years because of their inherent properties of flexibility,processability,and interfacial compatibility.However,the commercialization of SPEs remains challenging for flexible and high-energy-density LIBs.The incorporation of functional additives into SPEs could significantly improve the electrochemical and mechanical properties of SPEs and has created some historical milestones in boosting the development of SPEs.In this study,we review the roles of additives in SPEs,highlighting the working mechanisms and functionalities of the additives.The additives could afford significant advantages in boosting ionic conductivity,increasing ion transference number,improving high-voltage stability,enhancing mechanical strength,inhibiting lithium dendrite,and reducing flammability.Moreover,the application of functional additives in high-voltage cathodes,lithium-sulfur batteries,and flexible lithiumion batteries is summarized.Finally,future research perspectives are proposed to overcome the unresolved technical hurdles and critical issues in additives of SPEs,such as facile fabrication process,interfacial compatibility,investigation of the working mechanism,and special functionalities.

硫化物固态电解质Li_(6)PS_(5)Cl的固相合成及性能研究

通过高能球磨结合热处理的方法固相合成了硫银锗矿型硫化物固态电解质Li_(6)PS_(5)Cl(LPSC)。研究发现,延长球磨时间有利于原料粉末颗粒的破碎、混合、晶粒细化以及非晶化反应的进行;升高烧结温度有利于生成单一纯相,但烧结温度过高会使电解质熔化分解,破坏晶体结构。球磨时间10 h、550℃下烧结8 h所制备的硫化物固态电解质材料具有较高的离子电导率,可达3.57×10^(-3)S/cm。

LPEO enhanced LAGP composite solid electrolytes for lithium metal batteries

The application of solid electrolyte is expected to realize the commercialization of high energy density lithium metal batteries(LMBs).While the interfacial contact between solid inorganic electrolyte and electrodes has become a stumbling block for achieving stable cycling in LMBs.In this work,a Li-containing polyethylene oxide(LPEO)was introduced between LAGP and electrodes as a buffer layer to regulate the interfacial compatibility and reduce interfacial impedance,inhibiting the side reactions.Moreover,ether-oxygen bond on LPEO chain can coordinate with Li+and guide the transportation of Li+,achieving fast Li+diffusion between Li1+xAlxGe2-x(PO4)3(LAGP)and electrodes.Specifically,the growth of lithium dendrites is effectively suppressed in LAGP with LPEO modification,which would lead to remarkable cycling stability and rate capability.Therefore,the Li|LPEO-LAGP|Li battery can cycle stably for more than 600 h at 0.1 mA cm−2.In addition,long-term performance of Li|LPEO-LAGP|LiFePO4(LFP)battery was achieved at a rate of 0.4 C,and capacity retention is more than 74%after 200 cycles.The Li|LPEO-LAGP|LiNi0.8Co0.1Mn0.1O2 also realized the steady operation in the voltage range of 2.8-4.3 V.

聚合物固态电解质设计策略

电解质作为锂离子电池中最为关键的部分之一,决定了锂离子电池的性能。固态电解质相比传统的电解液具有良好的机械强度、优越的安全性等,其中聚合物固态电解质不仅极大降低了锂离子电池的安全隐患,同时表现出优异的机械加工性能,具有良好的弹性和柔韧性,易制备加工成不同的形状。相较于氧化物固态电解质,聚合物固态电解质的柔性使其能很好地贴合电极,阻抗低,合成条件较为简易,对温度、压力等环境要求不苛刻,适宜规模化生产。但聚合物固态电解质的发展应用仍然存在诸多阻碍,在室温下,其离子电导率远远达不到目前对于锂离子电池能量密度的理想需求。既要兼顾聚合物的离子电导率,又要尽可能保留机械强度,是目前需要解决的首要问题。需要搞清楚在分子层面影响聚合物固态电解质离子电导率和高压稳定性的因素,同时探索新型聚合物、共聚物、复合型材料用于其制备中。调节分子间相互作用是一种有前途的提高离子电导率的解决方案。目前相关研究主要集中在开发新型聚合物、开发有效添加剂、针对不同电池系统优化聚合物固态电解质的微观结构三个方面。

聚氧化乙烯-聚磷酸钠共混物的钠离子导电性

研究了聚氧化乙烯-聚磷酸钠共混物的钠离子导电性和低分子量多缩乙二醇对共混物导电性的改进作用。结果表明,降低多缩乙二醇的分子量以及增加其含量都有利于提高共混物的离子导电率。增塑剂改进共混物导电性的实质是提高共混物的非晶相含量,共混物内钠离子传导发生在非晶区,聚合物链段运动是离子传导的主要推动力。

高价阳离子固体电解质的研究进展

高价阳离子固体电解质在气体传感器、燃料电池等方面有着十分广阔的应用前景,被认为是一种很有前途的电解质材料。因此,作为一类新型材料,日益引起世界各国科学家的浓厚兴趣。综述了高价阳离子固体电解质的研究现状,重点介绍了铝离子固体电解质及其应用,同时分析了高价阳离子固体电解质现阶段面临的问题,展望了高价阳离子固体电解质的发展前景。

PEO/LiClO_4复合体系电解质膜的固体NMR研究

Lithium perchlorate/poly（ethylene oxide）complex,as potential polymer electrolytes,has attracted much research interests in the past decades,due to its great applicational significance.However,despite of great efforts,the mechanism of ion conducting of the system is still a topic with debates.In this work,the（）13C CP/MAS spectra of a series of PEO/LiClO4 complexes were measured with different compositions.It is found that for the extensively dried samples,the（）13C CP/MAS spectrum can exhibit up to 11 narrow peaks and the characteristics of the spectrum varies greatly with the composition.The（）13C spin-lattice relaxation time（T1）of these narrow peaks are found to be comparable to that of the neat PEO crystalline region,indicating these narrow peaks are corresponding to the complexed crystalline structures.On the other hand,the（）1H T1ρ of the narrow peaks are much longer than that of the neat PEO crystalline region,suggesting that the chain motion of PEO in the complex is greatly restricted due to the interaction between the oxygen of PEO and Li+.The aforementioned 11 peaks are assigned to three complexed crystalline structures.The conductivity of the complex sample decreases greatly when [O]∶ molar ratio decreases to 4∶1,while half of the （）13C peaks that are attributed to one crystalline structure varnish,indicating that there should exist certain kind of correlation between the complexed crystalline structure and the conductivity.

A review of solid electrolytes for safe lithium-sulfur batteries

Due to the high specific capacity, low cost, and environmental friendliness, lithium-sulfur batteries hold great potential to become the mainsiay of next-generation energy storage system. Regarding the composition of sulfur/carbon in cathode, flammable organic liquid electrolyte, and lithium metal anode, great concerns about the safety have been raised. Hence solid-electrolyte-based lithium-sulfur batteries, as one alternative route for safe batteries, are highly interested. This review highlights the recent research progress of lithium-sulfur batteries with solid electrolytes. Both sulfide solid electrolytes and oxide solid electrolytes are included. The sulfide solid electrolytes are mainly employed in all-solid-state lithium-sulfur batteries, while the oxide solid electrolytes are applied in hybrid electrolyte for lithium-sulfur batteries. The challenges and perspectives in this field are also featured on the basis of its current progress.

阳离子固体电解质的研究进展

近年来,固体电解质材料作为一种新型功能材料蓬勃发展并被广泛研究。论文主要就一价、二价、三价和四价阳离子传导固体电解质的研究进行了综述,着重介绍了三价和四价两种高价阳离子固体电解质的研究现状,简要介绍了固体电解质在电化学气体传感器方面的应用,总结了其在现阶段研究中遇到的问题,并对未来的应用和发展前景进行了展望。

固体电解质氧电池与应用

固体电解质氧电池的应用已取得了显著成效,本文系统地概述了该电池和定氧技术的原理与应用,并在实验条件下测定了△G_(Cu_2O)。

离子色谱法测定高热值混合糖电解质注射液中阴阳离子的含量

目的:建立离子色谱法(IC),同时测定高热值混合糖电解质注射液中6种阴离子(葡萄糖酸根、醋酸根、氯离子、硫酸根、磷酸根和枸橼酸根)及4种阳离子(钠离子、钾离子、镁离子和钙离子)的含量方法;方法:采用离子色谱仪,电导检测器检测;测定阴离子的色谱柱为IonPac AS23 column(250 mm×4 mm),流动相为氢氧化钾溶液,按浓度梯度洗脱(KOH浓度:0～8min为5 mmol.L-1,8.1～25 min为35 mmol.L-1,25.1～30 min为5 mmol.L-1);测定阳离子的色谱柱为IonPac SCS1 col-umn(250 mm×4 mm),流动相为6 mmol.L-1甲烷磺酸溶液。结果:本方法可在同台离子色谱仪上分别使用阴阳离子系统分析产品中各阴阳离子含量,各成分间分离良好,各成分的浓度和各自峰面积之间有着良好的线性关系,精密度及加样回收率的RSD均小于2.0%。结论:本方法快捷、准确、专属、精密、耐用,可较全面地控制产品质量。