A high-power and fast charging Li-ion battery with outstanding cycle-life

Electrochemical energy storage devices based on Li-ion cells currently power almost all electronic devices and power tools. The development of new Li-ion cell configurations by incorporating innovative functional components (electrode materials and electrolyte formulations) will allow to bring this technology beyond mobile electronics and to boost performance largely beyond the state-of-the-art. Here we demonstrate a new full Li-ion cell constituted by a high-potential cathode material, i.e. LiNi0.5Mn1.5O4, a safe nanostructured anode material, i.e. TiO2, and a composite electrolyte made by a mixture of an ionic liquid suitable for high potential applications, i.e. Pyr1,4PF6, a lithium salt, i.e. LiPF6, and standard organic carbonates. The final cell configuration is able to reversibly cycle lithium for thousands of cycles at 1000 mAg-1 and a capacity retention of 65% at cycle 2000. © 2017 The Author(s)

Nanostructured Materials Derived from Metal-Organic Frameworks for Energy and Environmental Applications

Nowadays, energy and environmental issues have become the top priority among a series of global issues. Fossil fuels as the dominant source are depleted fast and usually lead to some environmental problems. Heavy metal pollution has posed a severe threat to environment and public health. Metal-organic frameworks (MOFs), as a very promising category of porous materials, have attracted more and more interest in research communities due to their extremely high surface areas, diverse nanostructures and unique properties. To meet the ever-increasing energy demand and tackle the heavy metal pollution in water, MOFs can function as ideal templates to prepare various nanostructured materials for energy and environmental cleaning applications. The aim of this dissertation is to design and synthesize metal-organic frameworks (MOFs) derived nanomaterials with desirable structures, morphologies and compositions for energy applications in Li-ion batteries (LIBs), dye-sensitized solar cells (DSSCs) and electrocatalytic water splitting and environmental application in removal of heavy metal from aqueous systems. Their performances are mainly dependent on the characteristics of nanostructured materials. Briefly, the first two projects are focused on synthesis of ZIF-8 derived N-doped porous carbon and ZIF-67 derived ultrafine Co3O4 nanoparticles/carbon nanotube composites as high-performance anode materials for Li-ion batteries. The third project concentrates on synthesis of CoNi alloy embedded carbon nanocages derived from bimetallic organic frameworks for DSSCs. In addition, MOFs-derived CoNi and CoNx@Co/N-doped carbon tubes are synthesized and evaluated as low-cost electrocatalysts for efficient oxygen evolution reaction (OER). The last project is focused on study of ZIF-8 as an efficient absorbent for removal of copper ions from wastewater

Nano/Submicro-Structured Iron Cobalt Oxides Based Materials for Energy Storage Application

Supercapacitors, as promising energy storage devices, have been of interest for their long lifespan compared to secondary batteries, high capacitance and excellent reliability compared to conventional dielectric capacitors. Transition metal oxides can be applied as the electrode materials for pseudocapacitors and offer a much higher specific capacitance. Co3O4 is one of the most investigated transition metal oxides for supercapacitor. Besides simple monometallic oxides, bimetallic transition oxides have recently drawn growing attention in electrochemical energy storage. They present many unique properties such as achievable oxidation states, high electrical conductivities because of the coexistence of two different cations in a single crystal structure. This study focuses on the bimetallic iron cobalt oxide based materials for the application of energy storage. We selected iron as the substituent in spinel Co3O4, by virtue of its abundant and harmless character. Four types of iron cobalt oxides based electrode materials with different morphologies and components have been synthesized for the first time. The hydrothermal method was the main strategy for the synthesis of iron cobalt based materials, which achieved the control of morphology and ratio of components. Multiple characterization methods, including SEM, TEM, XRD, XPS, TGA, BET, have been applied to study the morphologies and nano/submicron structures. The electrochemical properties of as-fabricated samples were performed by electrochemical workstation. In addition, in order to investigate the practical application of electrode materials, asymmetric supercapacitors have been assembled by using as-prepared samples as the positive electrodes and activated carbon as the negative electrodes

Plasma processes in the preparation of lithium-ion battery electrodes and separators

Abstract: Lithium-ion batteries (LIBs) are the energy storage devices that dominate the portable electronic market. They are now also considered and used for electric vehicles and are foreseen to enable the smart grid. Preparing batteries with high energy and power densities, elevated cycleability and improved safety could be achieved by controlling the microstructure of the electrode materials and the interaction they have with the electrolyte over the working potential window. Selecting appropriate precursors, reducing the preparation steps and selecting more efficient synthesis methods could also significantly reduce the costs of LIB components. Implementing plasma technologies can represent a high capital investment, but the versatility of the technologies allows the preparation of powdered nanoparticles with different morphologies, as well as with carbon and metal oxide coatings. Plasma technologies can also enable the preparation of binder-free thin films and coatings for LIB electrodes, and the treatment of polymeric membranes to be used as separators. This review paper aims at highlighting the different thermal and non-thermal plasma technologies recently used to synthesize coated and non-coated active materials for LIB cathodes and anodes, and to modify the surface of separators