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101.
聚合物电解质主要分为凝胶聚合物电解质和固态聚合物电解质两种类型,均能够提升锂二次电池的性能。其中,凝胶聚合物电解质是利用增塑剂实现聚合物基质的凝胶化,将有机液态电解液固定在三维网络结构中,因此同时具备液态的离子扩散速率和固态材料的机械性能;而固态聚合物电解质是一种完全没有液态电解质的体系,利用聚合物基体的极性实现锂盐的解离,以聚合物分子链的运动实现离子传输。相对于传统的非原位法制备的聚合物电解质而言,原位聚合反应制备的聚合电解质能够有效改善电解质与电极的界面相容性、简化电池组装工艺、降低制造成本。本文综述了当前原位聚合电解质在锂二次电池中应用的研究进展,并展望了原位聚合电解质的应用前景和未来挑战。 相似文献
102.
Lithium-ion batteries(LIBs) have evolved into the mainstream power source of ene rgy sto rage equipment by reason of their advantages such as high energy density,high power,long cycle life and less pollution.With the expansion of their applications in deep-sea exploration,aerospace and military equipment,special working conditions have placed higher demands on the low-temperature performance of LIBs.However,at low temperatures,the severe polarization and inferior electrochemical activity of electrode materials cause the acute capacity fading upon cycling,which greatly hindered the further development of LIBs.In this review,we summarize the recent important progress of LIBs in low-temperature operations and introduce the key methods and the related action mechanisms for enhancing the capacity of the various cathode and anode materials.It aims to promote the development of high-performance electrode materials and broaden the application range of LIBs. 相似文献
103.
Dr. Lars Borchardt Dr. Martin Oschatz Prof. Dr. Stefan Kaskel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(22):7324-7351
Lithium–sulfur batteries are among the most promising electrochemical energy storage devices of the near future. Especially the low price and abundant availability of sulfur as the cathode material and the high theoretical capacity in comparison to state‐of‐the art lithium‐ion technologies are attractive features. Despite significant research achievements that have been made over the last years, fundamental (electro‐) chemical questions still remain unanswered. This review addresses ten crucial questions associated with lithium–sulfur batteries and critically evaluates current research with respect to them. The sulfur–carbon composite cathode is a particular focus, but its complex interplay with other hardware components in the cell, such as the electrolyte and the anode, necessitates a critical discussion of other cell components. Modern in situ characterisation methods are ideally suited to illuminate the role of each component. This article does not pretend to summarise all recently published data, but instead is a critical overview over lithium–sulfur batteries based on recent research findings. 相似文献
104.
High‐Loading Nano‐SnO2 Encapsulated in situ in Three‐Dimensional Rigid Porous Carbon for Superior Lithium‐Ion Batteries 下载免费PDF全文
Hairong Xue Dr. Jianqing Zhao Jing Tang Hao Gong Prof. Ping He Prof. Haoshen Zhou Prof. Yusuke Yamauchi Prof. Jianping He 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(14):4915-4923
Tin oxide nanoparticles (SnO2 NPs) have been encapsulated in situ in a three‐dimensional ordered space structure. Within this composite, ordered mesoporous carbon (OMC) acts as a carbon framework showing a desirable ordered mesoporous structure with an average pore size (≈6 nm) and a high surface area (470.3 m2 g?1), and the SnO2 NPs (≈10 nm) are highly loaded (up to 80 wt %) and homogeneously distributed within the OMC matrix. As an anode material for lithium‐ion batteries, a SnO2@OMC composite material can deliver an initial charge capacity of 943 mAh g?1 and retain 68.9 % of the initial capacity after 50 cycles at a current density of 50 mA g?1, even exhibit a capacity of 503 mA h g?1 after 100 cycles at 160 mA g?1. In situ encapsulation of the SnO2 NPs within an OMC framework contributes to a higher capacity and a better cycling stability and rate capability in comparison with bare OMC and OMC ex situ loaded with SnO2 particles (SnO2/OMC). The significantly improved electrochemical performance of the SnO2@OMC composite can be attributed to the multifunctional OMC matrix, which can facilitate electrolyte infiltration, accelerate charge transfer, and lithium‐ion diffusion, and act as a favorable buffer to release reaction strains for lithiation/delithiation of the SnO2 NPs. 相似文献
105.
The substitution of a small amount of Ga in the high-voltage spinel cathode LiMn1.5Ni0.42Ga0.08O4 leads to superior cyclability at room temperature and 55 °C along with higher rate capability with conventional electrolytes compared to that found with the LiMn1.5Ni0.5O4 cathode. The superior performance is attributed to the segregation of the inert Ga3+ ions to the surface during the synthesis process, providing a robust, more stable interface with the electrolyte at the high operating voltage (~ 4.7 V), along with the stabilization of the spinel structure with a disordering of the cations in the octahedral sites. 相似文献
106.
Carbon-coated monoclinic Li3V2(PO4)3 (LVP/C) cathode material has been successfully prepared by a novel glycine-assisted sol–gel method. The product is investigated by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM) and electrochemical method. In the range of 3.0–4.3 V, the LVP/C electrode presents excellent rate capability. It is 125.4 mAh g− 1 that can be delivered at 1 C charge–discharge rate and 99.5 mAh g− 1 is still obtained at 20 C charge–discharge rate. These results demonstrate that the carbon-coated LVP/C composite material prepared via a glycine-assisted sol–gel method has great potential for use in high-power lithium ion batteries. 相似文献
107.
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109.
Pauline Jaumaux Qi Liu Dr. Dong Zhou Xiaofu Xu Tianyi Wang Yizhou Wang Feiyu Kang Prof. Baohua Li Prof. Guoxiu Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(23):9219-9227
The deployment of high-energy-density lithium-metal batteries has been greatly impeded by Li dendrite growth and safety concerns originating from flammable liquid electrolytes. Herein, we report a stable quasi-solid-state Li metal battery with a deep eutectic solvent (DES)-based self-healing polymer (DSP) electrolyte. This electrolyte was fabricated in a facile manner by in situ copolymerization of 2-(3-(6-methyl-4-oxo-1,4-dihydropyrimidin-2-yl)ureido)ethyl methacrylate (UPyMA) and pentaerythritol tetraacrylate (PETEA) monomers in a DES-based electrolyte containing fluoroethylene carbonate (FEC) as an additive. The well-designed DSP electrolyte simultaneously possesses non-flammability, high ionic conductivity and electrochemical stability, and dendrite-free Li plating. When applied in Li metal batteries with a LiMn2O4 cathode, the DSP electrolyte effectively suppressed manganese dissolution from the cathode and enabled high-capacity and a long lifespan at room and elevated temperatures. 相似文献
110.
Huijun Yang Zhi Chang Dr. Yu Qiao Han Deng Xiaowei Mu Prof. Ping He Prof. Haoshen Zhou 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(24):9463-9467
Rechargeable aqueous zinc batteries (RAZB) have been re-evaluated because of the superiority in addressing safety and cost concerns. Nonetheless, the limited lifespan arising from dendritic electrodeposition of metallic Zn hinders their further development. Herein, a metal–organic framework (MOF) was constructed as front surface layer to maintain a super-saturated electrolyte layer on the Zn anode. Raman spectroscopy indicated that the highly coordinated ion complexes migrating through the MOF channels were different from the solvation structure in bulk electrolyte. Benefiting from the unique super-saturated front surface, symmetric Zn cells survived up to 3000 hours at 0.5 mA cm−2, near 55-times that of bare Zn anodes. Moreover, aqueous MnO2–Zn batteries delivered a reversible capacity of 180.3 mAh g−1 and maintained a high capacity retention of 88.9 % after 600 cycles with MnO2 mass loading up to 4.2 mg cm−2. 相似文献