Due to high safety, long service life and high energy density, all-solid-state lithium battery has a good application prospect in high-safety chemical power source field. As the key part of all-solid-state lithium battery, solid electrolytes have attracted lots of attention and have been thoroughly studied for many years, but only few solid electrolytes showed good performance. NASICON-type oxide electrolytes, garnet-type oxide electrolytes and sulfide electrolytes possess high conductivities at room temperature, thus have been regarded as solid electrolytes with great application potential. This article presents a brief review of the researches on these solid electrolytes from the aspects of structural characteristics, preparation and modifications. The challenges and prospects of the applications of solid electrolytes in all-solid-state lithium battery are also stated.

This bimonthly review paper highlights 100 recent published papers on lithium batteries. We searched the Web of Science and found 971 papers online from Oct.1,2014 to Nov. 30,2014. 100 of them were selected to be highlighted. Layered oxide and high voltage spinel cathode materials are still under extensive investigations. Large efforts were devoted to Si and Si based anode materials and electrolyte. There are a few papers related to Li/S battery, Li-air battery and more papers related to cell analyses, theoretical simulations, and modeling.

High temperature molten salt thermal energy storage unit has an irreplaceable role for solar thermal power generation for balancing energy supply and demand, and extending the working hours. It has become an indispensible sub-system for modern solar thermal power plants. Based on the project experience in installation and operation of a high temperature molten salt thermal energy storage unit containing a binary carbonate eutectic salt with a working temperature up to 850 ℃, this paper discusses some common engineering issues, including molten salt transportation pipe connections, anti-freezing/heat-tracing and thermal insulation of molten salt pipelines, salt charging / discharging, long-shaft molten salt pumps, and incident/accident prevention, etc.

In recent years, increasing attention has been attracted for using spinel NiCo₂O₄ nanostructure material in the field of supercapacitors owing to its excellent electrochemical activities. In this study, the researches of NiCo₂O₄ material for supercapacitors are reviewed in details, with emphasis on structure, synthetic method and modification of NiCo₂O₄ material. The applications and the research directions of NiCo₂O₄ material for supercapacitors are also forecasted.

With the aim to shed more light on the reaction mechanism of rechargeable Li/S batteries, a three electrode set-up and a two electrode coil cell were assembled to identify the possible oxidation process of polysulfides at the surface of mesoporous carbon material. Cyclic Voltammograms and galvanostatic potential profile were examined in high or low sulfur concentrations. The color change in electrolyte and at the surface of positive electrode of a three electrode set-up were studied in the redox process. Factors impact peak current at 2.6 V (vs. Li⁺/Li)include concentration of sulfur, component of electrolyte, specific area of carbon matrix were studied. It is necessary to maintain super-saturation of sulfur in electrolyte to complete the charging process;Sulfur is reduced to polysulfides and it dissolves into electrolyte at the discharging process. Polysulfides is oxidized to elemental sulfur , at the same time, it generateselemental sulfur through disproportionation at the charging process. The anodic peak current increases at enhanced area of carbon matrix. It decreases in carbonate electrolyte because the carbonate electrolyte has rather low solubility to sulfur and polysulfides; With the increase of the concentration of sulfur in electrolyte, the anodic peak current first increases proportionally, then decreases dramatically when concentration of sulfur exceeds a certain value. The appropriate total sulfur concentration in ether electrolyte is 0.125 mol/L.

Lithium-ion batteries (LIBs) are the state-of-the-art power sources for portable electronic devices. Furthermore, LIBs have now emerged as the most promising power source for electric vehicles, hybrid vehicles and plug-in hybrid vehicles. LIBs have some safety problems, such as the formation of lithium dendrite which can cause internal short-circuiting. In this paper, the cyclic performance of electrode in commercial lithium-ion battery is studied with a macro-micro experiment. Electrochemical experiment is carried at room temperature with small current G and the generation, growth, dissolution and residue of lithium dendrite are observed. It reveals that lithium dendrite can be formed not only under large-current overcharge or low-temperature charge but also under small current and at room temperature. It has been found that lithium dendrite appears in the late charge, stretching straightly, and its tip topography remains unchanged. Lithium dendrite begins dissolving when discharge, whose tip morphology still unchanged, and dead lithium residues on the electrode after fully discharge.

Components of locomotive will be abraded, deformed or damaged after a period of running, in order to make the locomotive running stably and reliably or to prolong its service life, periodic maintenance and testing must be conducted. At present, as a means of load test, the hydraulic resistance test has been widely used in locomotive diesel engine tests, the static continuous test will accounts 15%~30% of the energy production through the whole engine life. It will not only cause great waste of energy, and will also cause severe corrosion of metal plate. This paper proposes a novel embedded energy storage system used in an energy harvesting demo which is implemented to storage the power produced in diesel engine test process. This paper also describes the overall design of the demo and the function of the key equipment used. The simulation and test results show that this system is stable and reliable during energy harvesting.

With the rapid development of electric vehicle, there will be a large number of retired power batteries in the future. These retired batteries have considerable remaining capacity and lifetime, and can be used for energy storage. In order to improve the safety and output performances, the retired cells should be re-sorting and assembling in series/parallel. To study their performance of a battery using cells with distributed internal resistance, capacity, and initial SOC helps to the realization of the reuse of lithium iron phosphate power battery for energy storage.

Electrochemical measuring methods have been widely used in the scientific researches on lithium ion batteries for obtaining kinetic properties of electrode. In this paper, the features of electrode, electrochemical polarization and measuring methods are introduced firstly. The application of cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), galvanostatic intermittent titration technique (GITT) and potential relaxation technique (PRT) techniques in researches on lithium ion batteries is discussed mainly.

In order to meet increasing safety demands from coal industry and mining company, a lead acid and lithium iron phosphate (LFP) based battery energy storage is developed for a megawatt level emergency power supply in Pinggou coal mine of Wuhai, Inner Mongolia. If the local power grid works normally, the proposed system compensate the reactive power instead of the use of traditional static capacitor. When there is a local grid failure, the energy storage system provides stable power to extremely critical loads of coal mine for at least 30 min. Besides, the proposed energy storage system could also play a role in the ‘peak shaving’ and smoothing distributed energy generation for the demand side. To ensure safety, reliability and sufficient lifetime, the work is focused on the selection of batteries, capacity ratio of different batteries, circuit topology and smart control strategy design of the power conversion system.