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1.
利用无水乙醇离心洗涤法对LLZTO进行预处理,对LLZTO与PVDF溶液凝胶变色的原因进行了研究,通过XRD,FTIR,ICP测试手段对LLZTO中碱性杂质的成分进行了研究,对洗涤前后的LLZTO的离子电导率、固态电解质膜的离子电导率和SEM照片进行了对比,并对分别使用洗涤前后的LLZTO的固态锂离子电池的电化学性能进行了对比测试。结果表明,使得LLZTO与PVDF溶液凝胶变色的原因为LLZTO中的碱性杂质,其主要成分为LiOH。通过无水乙醇离心洗涤能对碱性杂质做到良好的去除,可以将LLZTO的离子电导率提高约1.668×10~(-4) S·cm~(-1),固态电解质膜的离子电导率提高约1×10~(-4) S·cm~(-1)。去除碱性杂质的固态电解质膜成膜性更好,并且其电池的循环稳定性更好,循环200圈过后比使用未洗涤的LLZTO的电池容量高约50 mAh·g~(-1)。  相似文献   

2.
介绍了纳米技术在氧离子导体和氟离子导体的制备及导电性能研究方面的应用。纳米尺度的氧化物在烧结过程中致密化温度可降低50~200℃,最终产物的晶粒尺寸可小于1μm,离子电导率较高,可达到10–1S·cm–1量级。纳米氟离子导体与传统粗晶氟离子导体相比,具有明显的纳米尺寸效应,导电激活能可降低30%,离子电导率可提高1~2个数量级。  相似文献   

3.
离子注入型超大容量固体离子电容器   总被引:2,自引:1,他引:1  
陈艾  陶凤波 《电子学报》1992,20(11):88-92
本文提出了一种具有“混合导体电极/快离子导体(或快离子导体粉体与炭质极化电极颗粒混合体)/混合导体电极”结构的离子注入型超大容量固体离子电容器.其电容量除由界面双电层形成外,研究还发现电容量随混合导体电极用量增加线性增大.研究采用Cu~(+)离子导体为固体电解质,Cu_2Mo_6S_7.7为混合导体电极.其容量密度高达50F/Cm~3,等效串联电阻(ESR)为40Ω,漏电流为15μA,分解电位为600mV.  相似文献   

4.
针对锂离子电池用无纺布隔膜孔径分布不均的问题,采用原纤化天丝纤维制备湿法无纺布基材,结合氧化物固态电解质涂层,在收窄孔径尺寸及区间分布的同时,降低电池内阻,提升电化学性能。固态电解质涂层搭配低转数无纺布隔膜会导致基材侧渗出大量陶瓷,但对于组装后电池循环及倍率测试无影响。涂覆之后的无纺布隔膜(LC10)组装钴酸锂全电池循环后拥有较低的极化电压,且由于拥有较高的离子迁移数及更低的欧姆电阻和电荷转移电阻,其在3C高倍率循环下的容量保持率可达85.93%。未涂覆固态电解质涂层的无纺布隔膜低温性能差于商品样,低温镀锂情况较商品样更加严重,而LC10低温下的初始比容量可达124.9 mAh/g,容量保留率为94.23%。  相似文献   

5.
液晶态兼具了固态和液态的优点,作为电解质材料可以兼顾安全性、离子传输率、加工性能、电化学稳定性和界面相容性等特点,受到了越来越多的关注和研究.热致液晶材料可以通过自组装构筑完整的一维、二维或三维离子传输通道,它是电解质研究中广泛关注的领域,特别是近晶相液晶态电解质构筑的稳定二维锂离子传输通道受到了广泛关注,相较于其他液...  相似文献   

6.
固态电池就是以固态电解质取代传统有机电解液的电池。相比采用有机电解液,固态电池有很多独特的优点,首先可以避免因过度充电、内部短路使电解液过热导致的爆炸、自燃等危险,安全性大幅提高;其次,因为内部固态,在封装形式上可以大大简化,并可高度集成,以满足不同的应用需求。固态电解质的传导速度比液态电解质快也使固态电池能实现更高的电压输出。固态电  相似文献   

7.
在聚合物电解质中添加Li_7La_3Zr_(1.4)Ta_(0.6)O_(12)(LLZTO)粉体可以降低聚合物材料的结晶度,促进锂离子迁移,进而提高固态电解质的离子电导率。以双三氟甲基磺酸亚酰胺锂(LiTFSI)、聚偏氟乙烯-六氟丙烯(PVDF-HFP)以及LLZTO粉体为原料制备了不同LLZTO含量的氧化物-聚合物复合固态电解质。研究发现,添加质量分数20%LLZTO的固态电解质具有较高的离子电导率以及高机械强度,同时具有更宽的电化学窗口(5.5 V)。所制备的复合正极/固态电解质/复合负极全固态锂离子软包电池首次充放电比容量分别为176.32和143.31 mAh/g,首次库伦效率为81.3%,25次循环后电池放电容量保持率维持在93%以上。此外,循环前后阻抗变化较小,表现出较好的界面稳定性。  相似文献   

8.
概括了目前CO气体传感器的国内外发展状况,提出了传统电化学气体传感器存在的问题,介绍了一种利用Nafion膜为固态电解质的CO气体传感器,阐述了它的工作原理.对电极材料、薄膜材料、固态电解液、电路等关键技术进行了讨论,重点介绍了电极的活化、液态电解质的固化及传感器的抗干扰、抗恶劣环境影响等技术研究,给出了传感器的结构和电路原理图,讨论了传感器的性能特点和发展方向.  相似文献   

9.
概括了目前CO气体传感器的国内外发展状况,提出了传统电化学气体传感器存在的问题,介绍了一种利用Nafion膜为固态电解质的CO气体传感器,阐述了它的工作原理。对电极材料?薄膜材料?固态电解液?电路等关键技术进行了讨论,重点介绍了电极的活化、液态电解质的固化及传感器的抗干扰、抗恶劣环境影响等技术研究,给出了传感器的结构和电路原理图,讨论了传感器的性能特点和发展方向。  相似文献   

10.
概括了目前CO气体传感器的国内外发展状况,提出了传统电化学气体传感器存在的问题,介绍了一种利用Nafion膜为固态电解质的CO气体传感器,阐述了它的工作原理。对电极材料?薄膜材料?固态电解液?电路等关键技术进行了讨论,重点介绍了电极的活化、液态电解质的固化及传感器的抗干扰、抗恶劣环境影响等技术研究,给出了传感器的结构和电路原理图,讨论了传感器的性能特点和发展方向。  相似文献   

11.
Ion gel electrolytes show great potential in solid‐state batteries attributed to their outstanding characteristics. However, because of the strong ionic nature of ionic liquids, ion gel electrolytes generally exhibit low lithium‐ion transference number, limiting its practical application. Amine‐functionalized boron nitride (BN) nanosheets (AFBNNSs) are used as an additive into ion gel electrolytes for improving their ion transport properties. The AFBNNSs‐ion gel shows much improved mechanical strength and thermal stability. The lithium‐ion transference number is increased from 0.12 to 0.23 due to AFBNNS addition. More importantly, for the first time, nuclear magnetic resonance analysis reveals that the amine groups on the BN nanosheets have strong interaction with the bis(trifluoromethanesulfonyl)imide anions, which significantly reduces the anion mobility and consequently increases lithium‐ion mobility. Battery cells using the optimized AFBNNSs‐ion gel electrolyte exhibit stable lithium deposition and excellent electrochemical performance. A LiFePO4|Li cell retains 92.2% of its initial specific capacity after the 60th cycle while the cell without AFBNNSs‐gel electrolyte only retains 53.5%. The results not only demonstrate a new strategy to improve lithium‐ion transference number in ionic liquid electrolytes, but also open up a potential avenue to achieve solid‐state lithium metal batteries with improved performance.  相似文献   

12.
For a variety of purposes, solid electrolytes with high ionic conductivity are believed to be an alternative to widely used liquid electrolytes. Most of them are developed based on the exploration of crystalline or amorphous structures. As a very rare example of the beneficial influence of glass/ceramic interfaces, we report the conductivity of LiF films on SiO2. The LiF thin films are surprisingly found to be structurally disordered on the silica (0001) surface, leading to a remarkable enhancement of the Li‐ion conductivity (6 × 10?6 S cm?1 at 50 °C, with an activation energy of 0.55 eV) of three orders of magnitude. The resulting conductivity is not exceedingly high, but is comparable with that of the current, best thin‐film solid electrolyte (Li(3 + x)PO(4 ‐ x)Nx). The conductivity is highest if a significant density of glass/ceramic interfaces is achieved and percolation of the interfaces guaranteed.  相似文献   

13.
Today, there is an urgent demand to develop all solid-state lithium-ion batteries (LIBs) with a high energy density and a high degree of safety. The core technology in solid-state batteries is a solid-state electrolyte, which determines the performance of the battery. Among all the developed solid electrolytes, composite polymer electrolytes (CPEs) have been deemed as one of the most viable candidates because of their comprehensive performance. In this review, the limitations of traditional solid polymer electrolytes and the recent progress of CPEs are introduced. The effect and mechanism of inorganic fillers to the various properties of electrolytes are discussed in detail. Meanwhile, the factors affecting ionic conductivity are intensively reviewed. The recent representative CPEs with synthetic fillers and natural clay-based fillers are highlighted because of their great potential. Finally, the remaining challenges and promising prospects are outlined to provide strategies to develop novel CPEs for high-performance LIBs.  相似文献   

14.
Shape-persistent, conductive ionogels where both mechanical strength and ionic conductivity are enhanced are developed using multiphase materials composed of cellulose nanocrystals and hyperbranched polymeric ionic liquids (PILs) as a mechanically strong supporting network matrix for ionic liquids with an interrupted ion-conducting pathway. The integration of needlelike nanocrystals and PIL promotes the formation of multiple hydrogen bonding and electrostatic ionic interaction capacitance, resulting in the formation of interconnected networks capable of confining a high amount of ionic liquid (≈95 wt%) without losing its self-sustained shape. The resulting nanoporous and robust ionogels possess outstanding mechanical strength with a high compressive elastic modulus (≈5.6 MPa), comparable to that of tough, rubbery materials. Surprisingly, these rigid materials preserve the high ionic conductivity of original ionic liquids (≈7.8 mS cm−1), which are distributed within and supported by the nanocrystal network-like rigid frame. On the one hand, such stable materials possess superior ionic conductivities in comparison to traditional solid electrolytes; on the other hand, the high compression resistance and shape-persistence allow for easy handling in comparison to traditional fluidic electrolytes. The synergistic enhancement in ion transport and solid-like mechanical properties afforded by these ionogel materials make them intriguing candidates for sustainable electrodeless energy storage and harvesting matrices.  相似文献   

15.
Thermotropic liquid‐crystalline (LC) electrolytes for lithium‐ion batteries are developed for the first time. A rod‐like LC molecule having a cyclic carbonate moiety is used to form self‐assembled two‐dimensional ion‐conductive pathways with lithium salts. Electrochemical and thermal stability, and efficient ionic conduction is achieved for the liquid crystal. The mixture of the carbonate derivative and lithium bis(trifluoromethylsulfonyl)imide is successfully applied as an electrolyte in lithium‐ion batteries. Reversible charge–discharge for both positive and negative electrodes is observed for the lithium‐ion batteries composed of the LC electrolyte.  相似文献   

16.
Despite significant interest toward solid‐state electrolytes owing to their superior safety in comparison to liquid‐based electrolytes, sluggish ion diffusion and high interfacial resistance limit their application in durable and high‐power density batteries. Here, a novel quasi‐solid Li+ ion conductive nanocomposite polymer electrolyte containing black phosphorous (BP) nanosheets is reported. The developed electrolyte is successfully cycled against Li metal (over 550 h cycling) at 1 mA cm?2 at room temperature. The cycling overpotential is dropped by 75% in comparison to BP‐free polymer composite electrolyte indicating lower interfacial resistance at the electrode/electrolyte interfaces. Molecular dynamics simulations reveal that the coordination number of Li+ ions around (trifluoromethanesulfonyl)imide (TFSI?) pairs and ethylene‐oxide chains decreases at the Li metal/electrolyte interface, which facilitates the Li+ transport through the polymer host. Density functional theory calculations confirm that the adsorption of the LiTFSI molecules at the BP surface leads to the weakening of N and Li atomic bonding and enhances the dissociation of Li+ ions. This work offers a new potential mechanism to tune the bulk and interfacial ionic conductivity of solid‐state electrolytes that may lead to a new generation of lithium polymer batteries with high ionic conduction kinetics and stable long‐life cycling.  相似文献   

17.
High-performance n-type solid-state ionic thermoelectrics (SS i-TEs) for low-grade heat harvesting are highly desired and challenging. Here, the design and synthesis of an efficient n-type mixed conductor via ion pair modulation is demonstrated, which consists of biguanide hydrochloride (MfmCl) and a poly(3,4-ethylenedioxythiophene) (PEDOT): poly(styrenesulfonate) (PSS) polymeric complex in a solid film. Theoretical calculations and nano/microstructure characterization reveal that the binding preference of ion pairs offers energetically favorable ion exchange in the matrix, which induces not only tightly bound Mfm PSS species but also favorable anion diffusion channels. Consequently, an enhanced ionic conductivity of 1.40 S m−1 with a record highest negative thermopower of −46.97 mV K−1 is achieved for the n-type mixed conductor thus far.  相似文献   

18.
Complex hydrides have energy storage‐related functions such as i) solid‐state hydrogen storage, ii) electrochemical Li storage, and iii) fast Li‐ and Na‐ionic conductions. Here, recent progress on the development of fast Li‐ionic conductors based on the complex hydrides is reported. The validity of using them as electrolytes in all‐solid‐state lithium rechargeable batteries is also examined. Not only coated oxides but also bare sulfides are found to be applicable as positive electrode active materials. Results related to fast Na‐ionic conductivity in the complex hydrides are presented. In the last section, the future prospects for battery assemblies with high‐energy densities, and Mg ion batteries with the liquid and the solid‐state electrolytes are discussed.  相似文献   

19.
Solid-state lithium batteries are considered promising energy storage devices due to their superior safety and higher energy density than conventional liquid electrolyte-based batteries. Lithium aluminum germanium phosphate (LAGP), with excellent stability in air and good ionic conductivity, has gained tremendous attention over the past decades. However, the poor interface compatibility with Li anode, slow Li-ion conduction in thick pellets, and high-temperature sintering procedure limit the further development of LAGP solid electrolytes in practical applications. This review comprehensively summarizes the crystal structure, Li-ion conducting mechanism, and various synthesis methods, especially the latest thin-film preparation approach. The underlying reason for Li/LAGP interfacial instability is identified, followed by several advanced interface engineering strategies, for example, introducing a functional interlayer. The integration design of LAGP-based solid electrolytes and cathode is also highlighted to enable high-loading cathodes. Additionally, recent progress of lithium-oxygen and lithium-sulfur batteries with LAGP-based solid electrolytes is discussed. Moreover, the different Li-ion migration pathways, preparation procedures, and electrochemical performance of polymer-LAGP composite solid electrolytes in Li-ion batteries are introduced. Lastly, the remaining challenges and opportunities are proposed to encourage more efforts in this field. This review aims to provide fundamental insights and promising directions toward practical LAGP-based solid-state batteries.  相似文献   

20.
Solid‐state lithium metal (Li°) batteries (SSLMBs) are believed to be the most promising technologies to tackle the safety concerns and the insufficient energy density encountered in conventional Li‐ion batteries. Solid polymer electrolytes (SPEs) inherently own good processability and flexibility, enabling large‐scale preparation of SSLMBs. To minimize the growth of Li° dendrites and cell polarization in SPE‐based SSLMBs, an additive‐containing single Li‐ion conductive SPE is reported. The characterization results show that a small dose of electrolyte additive (2 wt%) substantially increases the ionic conductivity of single Li‐ion conductive SPEs as well as the interfacial compatibility between electrode and SPE, allowing the cycling of SPE‐based cells with good electrochemical performance. This work may provide a paradigm shift on the design of highly cationic conductive electrolytes, which are essential for developing safe and high‐performance rechargeable batteries.  相似文献   

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