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A 3D cone separator geometry for lithium-ion batteries has been optimized taking into account the increase of radius size of one side. Theoretical simulations have been carried out for evaluating the influence of radius size in the cone structure at different discharge rates (1 C and 60 C) in which it was also determined the produced ohmic heat. The value of the discharge capacity in the cone structure depends on the increases of the radius, which is correlated with the electrolyte volume and interface between free electrolyte/cathode. The optimum balance of these parameters is essential for obtaining higher battery performance through this geometry that can be used in the next generation of lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Optimizing cathode electrode formulation is essential in the development and performance of lithium-ion batteries, as the cathode affects the capacity of the battery. Cathode electrode formulation is based on different materials and relative contents. In this work, the cathode performance for the LiMn2O4, LMO, active material has been obtained by theoretical simulations for different materials formulations and at various discharge rates. Further, the simulations were compared with experimental results. It is demonstrated that the optimization of the electrode formulation strongly depends on the percentage of conductive material, existing a minimum conductive filler content that optimizes the delivered capacity of the battery and being that delivery capacity independent of the conductive filler content for higher concentrations. [ABSTRACT FROM AUTHOR]

Lithium bis (oxalate) borate (Li BOB) has attracted much attention as a lithium salt or an additive in no aqueous electrolyte for lithium-ion battery. In this work, the formation of a solid electrolyte interphase (SEI) film of sulfolane (SL) with Li BOB was studied by employment of dimethyl sulfite (DMS) as mixed solvents. When used in Li/ MCMB (mesosphere carbon micro beads) cells, cell with 0.7M Li BOB-zSL/DMS (1:1) electrolyte at high temperature shows lower impedance than that at room temperature. The scanning electron microscope (SEM) results find that 0.7M Li BOBSL/ DMS (1:1) electrolyte at high temperature shows excellent film-forming characteristics than that at room temperature. The Li2SO3, ROSO2Li, Li2S, Li2CO3 substances are found in SEI film by X-ray photoelectron spectroscopy (XPS). It suggests that Li BOB-SL/DMS electrolyte has an excellent solid electrolyte interphase formation capacity. [ABSTRACT FROM AUTHOR]

Lithium vanadate Li3VO4 (LVO) is known to be as one of the attractive candidates for negative electrode of lithium-ion battery (LIB) with high safety. Although theoretical capacity of LVO attains to 400 mAh g-1, the actual charge and discharge capacities are far below due to its low electrical and ionic conductivity. In this study, we synthesized carbon-coated LVO (C-LVO) via one-step solid state reaction method and examined its properties as a negative electrode for LIB. From XRD measurements and SEM observation, crystal structure of C-LVO was nearly identical with non-coated one but grain size of former was much smaller than latter with same annealing temperature, suggesting that introduction of carbon source in starting materials effectively helps to suppress LVO grain growth during annealing. TEM observation of C-LVO also shows that amorphous carbon layer with its thickness of several ten nm was formed on the surface of LVO grain. In electrochemical testing, C-LVO shows much higher charge and discharge capacities than non-coated LVO. [ABSTRACT FROM AUTHOR]

Thermal analysis of battery geometries is essential for applications, as the thermal behavior of a battery influences its cycling life. Two geometries, square frame and conventional, have been studied for a scan rate of 290C. The square frame shows a capacity value of 290,15 Ahm-2 which is 446 times higher than the one for the conventional geometry, when the area is maintained constant for all components. In the adiabatic model, the square frame geometry has higher capacity value in comparison to the conventional geometry. [ABSTRACT FROM AUTHOR]

system is proposed based on NaS battery and lithium ion battery, that the former is the main large scale energy storage technology world-widely used and developed and the latter is a flexible way to have both power and energy capacities. The hybrid energy storage system, which takes advantage of the two complementary technologies to provide large power and energy capacities, is chosen to do an evaluation of economical-environmental based on critical excess electricity production (CEEP), CO2 emission, annual total costs calculated on the specific given condition using Energy PLAN software. The result shows that hybrid storage system has strengths in environmental benefits and also can absorb more discarded wind power than single storage system and is a potential way to push forward the application of wind power and even other types of renewable energy resources. [ABSTRACT FROM AUTHOR]

Tailoring battery geometries is essential for many applications, as geometry influences the delivered capacity value. Two geometries, frame and conventional, have been studied and, for a given scan rate of 330C, the square frame shows a capacity value of 305,52 Ahm-2, which is 527 times higher than the one for the conventional geometry for a constant the area of all components. [ABSTRACT FROM AUTHOR]

There are two indicators of battery performance, i.e : capacity and the internal resistance of battery. In this research, the affect of glucose addition to decrease the internal resistance of lithium battery was investigated. The ratio of glucose addition were varied at weight ratio 1%, 3%, and 5% and one mixtures without glucose addition. Lithium ferri phosphate (LiFePO4), polyvinylidene fluoride (PVDF), acetylene black (AB) and glucose were materials that used in this study. Both of mixtures were mixed in the vacuum mixer until became homogeneous. The slurry was coated on an aluminium foil sheet and the coated thickness was 200 µm. The performance of battery lithium was examined by Eight Channel Battery Analyzer and the Internal resistance was examined by Internal Resistance of Battery Meter. The result from all analyzer were showed that the internal resistance reduced as well as the battery capacity. The best internal resistance value is owned by mixtures with 3wt% ratio glucose addition. It has an internal resistance value about 64 miliohm. [ABSTRACT FROM AUTHOR]

The comparison between two different methods of synthesize of solid electrolyte Li3PO4 as precursor material for developing lithium ion battery, has been performed. The first method is to synthesize Li3PO4 prepared by wet chemical reaction from LiOH and H3PO4 which provide facile, abundant available resource, low cost, and low toxicity. The second method is solid state reaction prepared by Li2CO3 and NH4H2PO4. In addition, the possible morphology identification of comparison between two different methods will also be discussed. The composition, morphology, and additional identification phase and another compound of Li3PO4 powder products from two different reaction are characterized by SEM, EDS, and EIS. The Li3PO4 powder produced from wet reaction and solid state reaction have an average diameter of 0.834 - 7.81 µm and 2.15 - 17.3 µm, respectively. The density of Li3PO4 prepared by wet chemical reaction is 2.238 gr/cm³, little bit lower than the sample prepared by solid state reaction which density is 2.3560 gr/cm³. The EIS measurement result shows that the conductivity of Li3PO4 is 1.7 x 10-9 S.cm-1 for wet chemical reaction and 1.8 x 10-10 S.cm-1 for solid state reaction. The conductivity of Li3PO4 is not quite different between those two samples even though they were prepared by different method of synthesize. [ABSTRACT FROM AUTHOR]

The improvement of LiFePO4 (LFP) cathode performance has been performed by addition of Graphene (LFP+Graphene). The cathode was prepared from the active material with 5 wt % graphene and 10 wt % polyvinylidene fluoride in an n-methyl pyrrolidone solvent. Another cathode material used only 5% artificial graphite for comparison (LFP+Graphite). The crystal structure, microstructure, electronic conductivity, electrochemical impedance spectroscopy (EIS) of the cathodes were characterized by X-ray diffraction, SEM, and Impedance spectroscopy, respectively. Two half cell coin batteries were assembled using a lithium metal as an anode and LiPf6 as an electrolyte, and two cathodes (LFP+Graphene) and (LFP+Graphite). Charge discharge performance of battery was characterized by Battery analyser (BTS 8). The electronic conductivity of cathode with grapheme increased of about one order magnitude compared with the only cathode with graphite, namely from 1.97E-7S/cm (LFP+Graphite) to 1.92E-6S/cm (LFP+Graphene). The charge-discharge capacity after 10th cycles of LiFePO4 with graphene decreased of about 0.68% from 114.3 mAh/g to113.1 mAh/g, while LFP with graphite decreased of about 2.84% from 110.2 mAh/g to 107.1 mAh, at 0.1C-rates. It could be concluded that the addition of graphene has increased the ionic conductivity, and improved performance of the LFP lithium ion battery, such as higher capacity and better efficiency. [ABSTRACT FROM AUTHOR]

A study on the electrochemical performance of LiFePO4 based cylinder cell battery has been done. The measurements have been carried out using cyclic voltametry (CV), charge-discharge (CD), and electrochemical impedance spectroscopy (EIS). The CV profiles showed that the battery exhibited anodic (charge) peak and chatodic (discharge) peak when scanned between 2.5 and 4.2V at various scan rate of 1 to 0.05 mV/s. The CD result showed that the battery capacity was 700 mAh exhibited excellent capacity retention with efficiency was about 100% after 100 cycles. From EIS measurement, it was also observed that the battery resistance decreased with the state of charge. [ABSTRACT FROM AUTHOR]

In order to develop all solid lithium ion battery, study on the structure and properties of solid polymer electrolytes (SPE) based on chitosan has been done. The SPE were prepared by adding Zirconia (ZrO2) nanoparticle and LiClO4 as lithium salt into the chitosan solution followed by casting method. Effect of the ZrO2 and salt concentration to the structure and properties of SPE were elaborated using several methods. The structure of the SPE cast film, were characterized mainly by using X-ray diffractometer (XRD). While the electrical properties of SPE were studied by electrochemical impedance spectrometer (EIS) and ion transference number measurement. XRD profiles show that the addition of ZrO2 and LiClO4 disrupts the crystality of chitosan. The decrease in sample crytalinity with the nanoparticle and salt addition may increase the molecular mobility result in the increasing sample conductivity and cathionic transference number as determined by EIS and ion transference number measurement, respectively. The highest ionic conductivity (3.58 × 10-4 S cm-1) was obtained when 4 wt% of ZrO2 nanoparticle and 40 wt% of LiClO4 salt were added to the chitosan. The ion transference number with that composition was 0.55. It is high enough to be used as SPE for lithium ion battery. [ABSTRACT FROM AUTHOR]

With increasing demand for electrical power on a distribution grid lacking storage capabilities, utilities and project developers must stabilize what is currently still intermittent energy production. In fact, over half of utility executives say "the most important emerging energy technology" is energy storage. Advanced, low-cost battery designs are providing promising stationary storage solutions that can ensure reliable, high-quality power for customers, but research challenges and questions lefts. Have lithium-ion batteries (LIBs) reached their technical limit? The industry demands are including high costs, inadequate energy densities, long recharge times, short cycle-life times and safety must be continually addressed. Safety is still the main problem on developing the lithium ion battery. The safety issue must be considered from several aspects, since it would become serious problems, such as an explosion in a Japan Airlines 787 Dreamliner's cargo hold, due to the battery problem. The combustion is mainly due to the leakage or shortcut of the electrodes, caused by the liquid electrolyte and polymer separator. For this reason, the research on solid electrolyte for replacing the existing liquid electrolyte is very important. The materials used in existing lithium ion battery, such as a separator and liquid electrolyte must be replaced to new solid electrolytes, solid materials that exhibits high ionic conductivity. Due to these reasons, research on solid state ionics materials have been vastly growing worldwide, with the main aim not only to search new solid electrolyte to replace the liquid one, but also looking for low cost materials and environmentally friendly. A revolutionary paradigm is also required to design new stable anode and cathode materials that provide electrochemical cells with high energy, high power, long lifetime and adequate safety at competitive manufacturing costs. Lithium superionic conductors, which can be used as solid electrolytes, promise the potential to replace organic liquid electrolytes and thereby improve the safety of next-generation high-energy batteries. Li3PO4 has been proved to be a good candidate for solid electrolyte, due to its easy in preparation, low cost, high melting temperature and good compatibility with the electrode materials. In the present work, Li3PO4 has been prepared by wet chemical reaction, a simple method with the advantage of recycling a waste product H3PO4. The crystal structure has been characterized by both neutron and x-ray diffraction. The use of neutron scattering plays important role on observing the light atoms such as lithium ion. The x-ray diffraction results showed the crystal structure of orthorhombic phase P m n 21 (31), that belongs to the β-Li3PO4, with the lattice parameters are a = 6.123872, b = 5.250211, c = 4.876378. The conductivity of β-Li3PO4 was around 10-8 S/cm. Furthermore, the future application of the solid electrolyte layer in lithium ion battery will also be considered. It is concluded that the used of local resources on producing the solid electrolyte Li3PO4 for lithium ion battery will give more added values to the researches and national industry. [ABSTRACT FROM AUTHOR]

This research has been done on the synthesis of carbon coated LiFePO4 through sol-gel process. Carbon layer serves for improving electronic conductivity, while the variation of pH in the sol-gel process is intended to obtain the morphology of the material that may improve battery performance. LiFePO4/C precursors are Li2CO3, NH4H2PO4 and FeC2O4.H2O and citric acid. In the synthesis process, consisting of a colloidal suspension FeC2O4.H2O and distilled water mixed with a colloidal suspension consisting of NH4H2PO4, Li2 CO3, and distilled water. Variations addition of citric acid is used to control the pH of the gel formed by mixing two colloidal suspensions. Sol in this study had a pH of 5, 5.4 and 5.8. The obtained wet gel is further dried in the oven and then sintered at a temperature 700°C for 10 hours. The resulting material is further characterized by XRD to determine the phases formed. The resulting powder morphology is observed through SEM. Specific surface area of the powder was tested by BET, while the electronic conductivity characterized with EIS. [ABSTRACT FROM AUTHOR]

In this study, we focused on production of RGO by reduction of GO. GO was obtained via an improved Hummers' method. Chemical reduction of GO with hydrazine and with sodium borohydride were conducted. Effects of the used reduction procedures on RGOs' properties were investigated. Consequently, an easily controllable procedure was reached and several RGO gradients were synthesized. The synthesized RGO samples were investigated by XRD, SEM, EDAX, FTIR, TGA, BET and Raman spectroscopy. Crystallographic structure, morphologic appearance, and elemental ingredients of RGOs' were identified. Nearly 9,5:1 C:O ratio was reached. Using the resulted RGO as anode support material in lithium ion battery is planned to improve batteries charge capacity. [ABSTRACT FROM AUTHOR]

In recent years, there have been an increasing number of cases where a company tried to develop core technology for its own products by conducting joint research with a company in different industries. While, the mechanism for acquiring and absorbing technologies through joint research by companies in different industries remains unclear. Therefore, this paper developed a theoretical framework of this mechanism, created hypotheses, and examined by a data of a joint research conducted by Toyota Motor Corporation and Panasonic Corporation to develop the nickel-hydrogen storage cell. Specifically, this paper analyses the network of inventors who filed patent applications through the joint research. The results indicate that there are 'boundary mediators' who mediated the exchange of technologies between the two companies. There are three types of boundary mediators, characterised by their wide range of technical knowledge. [ABSTRACT FROM AUTHOR]

Researchers and developers use battery models in order to predict the performance of batteries depending on external and internal conditions, such as temperature, C-rate, Depth-of-Discharge (DoD) or State-of-Health (SoH). Most battery models proposed in the literature require specific laboratory test for parameterization, therefore a great majority do not represent an appropriate and feasible solution. In this paper three easy-to-follow equivalent circuit modeling methods based only on information contained in a commercial Li-Ion cell manufacturer's datasheet are presented and validated at steady state, comparing simulation results and manufacturer's curves. Laboratory results are included in order to demonstrate the accuracy of parameters estimation. Results of each method are presented, compared and discussed for a Kokam SLPB 120216216 53Ah Li-Ion cell. [ABSTRACT FROM PUBLISHER]

Electrification is regarded as the mainstream for future automobile power-train in order to cope with the impending energy and environmental problems. The technology of electric vehicle (EV), including battery powered vehicle, hybrid vehicle and fuel cell vehicle, has been investigated thoroughly for more than two decades in China. Many remarkable progresses have been achieved. In this paper, the R & D of electric vehicle technology in China are introduced. Both battery and motor development for electric vehicle application are summarized. The technology trend of electric motor drive is discussed accompanying with the introduction of the practice in electric motor drive research in Chinese Academy of Sciences. [ABSTRACT FROM PUBLISHER]

The article describes the development of the high energy type lithium-ion battery system for underwater use. The system is composed of a lithium-ion battery cell-assembly, a pressure-balanced case, and a battery manager. A sheet-type sealed battery cells and a chassis make up the cell-assembly while battery charge and discharge process management will be done by the battery manager. A review of battery development trends in the world is also provided.