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The polylactide and carbon addition to LiFePO4 has been studied to investigate the behavior of LiFePO4/C composite. The cathode material of LiFePO4 was prepared by coprecipitation of LiOH.H2O, (NH4)2HPO4, and FeSO4.7H2O solution. The resulting LiFePO4 was mixed with biodegradable polymer PLA in the concentration of 6, 8, 10, and 12 % weight of the polymer. Heat treatment was done by heating the precursor at 700 o C for 4 hours. The physical chemistry properties of cathode materials were analyzed by using Simultaneous Thermal Analysis (STA), X-Ray Diffractometer (XRD), Scanning Electron Microscope (SEM), and Particle Size Analyzer (PSA) methods. High Precision LCR-meter was used to perform conductivity measurement, in which the LiFePO4/C powder samples were prepared by using a 200 kg/cm2 hydraulic press. TG analysis informs gradual weight decrease at LiFePO4 temperature formation of 470 C and pyrolisis of remaining PLA occurs at 600 C. From all samples, XRD data indicate the pure phase of LiFePO4. SEM image shows the uniform distribution particle of the sample with 6 % PLA content with a conductivity of 1.99 X 10-2 Scm-1.

Most solid electrolyte materials have not shown enough conductivity to be used as an electrolyte for a battery in electronic devices. The mixture of 1.5 Li2O and P2O5 has been reported to show a good conductivity higher than that of Li3PO4, which is thought to be due to phase mixtures that are formed during manufacturing process. Montmorillonite (MMT) was used to explore the effect of phase mixture on conductivity of new 1.5Li2O-P2O5-MMT solid electrolyte composite, which was prepared through conventional solid-state reaction procedures. This study was conducted, how the addition of MMT affects process of forming 1.5Li2O-P2O5-MMT compound, and whether it influences electrical properties and permittivity of compound. Morphology, hygroscopicity, and electrochemical characteristics of this material were analyzed in this study. The shape of glassy-like flakes was reduced in micrographs, and granular lumps were getting larger as MMT was added. Addition also tended to reduce hygroscopicity, as indicated by a reduced rate of porous absorption. Whole Nyquist plot consisted of only one imperfect semicircular arc, indicating only one relaxation process occurred in materials. Capacitance of all arcs indicated main contribution of response was from bulk material. Slope of dielectric loss of samples indicated that conduction in the samples was mainly dominated by dc conduction. MMT clays acted as a medium that absorbed liquid phase in solid-state reaction, increasing formation of dominant phase, which determined total conductivity of compound. Conductivity was higher than that of Li4P2O7, where the sample of 20 wt% MMT addition was most polarizable and most dielectric compound.

Synthesis of LiFe1-xGdxPO4/C with (x = 0.01; 0.05; 0.07) have been carried out using a solid-state method from LiH2PO4, Fe2O3, Gd2O3, and Carbon. Al reactant are mixed and mashed with a ball milling for 8 hours, then heated at 80°C for 2 hours to evaporate free water. To complete the reaction, the sample then was sintered at two different temperature; first at 350°C for 6 hours and continue at 830°C for 10 hours under Argon gas (Ar) atmosphere. The sintered powder was characterized by XRD to determine the structure and phase purity. Sample LiFe1-xGdxPO4/C (x = 0.01; 0.05; 0.07) was adopted orthorhombic crystal structure and pnma space group, and no impurities detected. In general, the lattice parameter decreases with increasing Fe concentration, because of the size of the Fe3+ ion is smaller than that Gd3+ ion. Conductivities of LiFe0.93xGd0.07PO4/C, LiFe0.95Gd0.05PO4/C and LiFe0.99Gd0.01PO4/C are 2.17 x 10-4 S/cm, 1.54 x 10-4 S/cm, and 2.02 x 10-4 S/cm, respectively.

Li4Ti5O12/Sn was successfully synthesized by a solid-state method using the High Energy Ball Mill Machine as anode for Lithium-Ion batteries. The addition of various (10%, 20%, 30%) Sn-micro particle is aimed to enhance LTO's conductivity and capacity. Characterization of the sample's structure was performed using X-ray diffraction (XRD), which expose the presence of TiO2 rutile and Sn in each sample. The surface area of samples observed using Brunner-Emmet-Teller (BET), which indicates the different surface area of each Sn addition. Scanning electron microscopy (SEM) suggested agglomeration and poor distribution appear in every sample. Cyclic voltammetry (CV) was performed to measure the battery's performance. Two peaks occur as a sign of reversible reaction. The impedance of Li4Ti5O12/Sn measured using electrochemical impedance spectroscopy (EIS), the test performed before and after Cyclic voltammetry (CV), each test showed the different result for each sample. Other than EIS and CV, Charge-Discharge (CD) also performed, examinations in different C-rate were performed, and higher Sn concentration leads to lower stability in high C. The result reveals that the addition of 20% Sn optimizes Li4Ti5O12 in enhancing capacity and conductivity.

In this paper, we report the effect of a small quantity of acetonitrile (ACN) addition to an ionic liquid-based electrolyte for lithium-ion (Li-ion) batteries, which is comprised of lithium bis(trifluoromethylsulfonyl)imide (LiTFSI) salt dissolved in 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (BMIMTFSI). The addition of a small amount of ACN results in the increase of ionic conductivity, and at a proper molal fraction, it may significantly improve the charge-discharge capacity of its half-cell battery. A large amount of ACN addition, however, reduces the specific capacity because ACN molecules are more susceptible to irreversible redox reactions at the battery electrodes. The experimental results are also compared with the X-ray diffraction (XRD pattern) of the solutions, which may lead to a suggestion in the formation of coordination complexes between the Li+ cations with ACN molecules, which effectively hinders the formation of strong Li+-TFSI− ionic bonding and therefore increases the Li+ cation mobility. Different from other reports, the role of this small quantity of ACN is considered not only as a co-solvent, but also as an additive to this LiTFSI/BMIMTFSI electrolyte.

Batteries on the market today still use liquid-type electrolytes, which can result in safety issues caused by electrolyte leakage. Therefore, studies that search for solid-state electrolytes are important for resolving these issues. In this research, a composite of lithium phosphate-montmorillonite-polyvinylidene fluoride (Li3PO4-MMT-PVDF) has been characterized with the aim of detecting the electrochemical performance of Li3PO4 with the addition of MMT. Li3PO4 samples were prepared through a solid-state reaction, which was then mixed with MMT, which had a composition ranging from 5 wt% to 20 wt%, and 1 wt% PVDF as a binder. This characterization was conducted with structural, morphological, and electrochemical aspects. The structural test showed that the X-ray diffraction (XRD) pattern was dominated by Li3PO4 peaks and MMT aluminosilicates. The electrochemical characterization indicated that the conductivity value of the composites was greater than that of Li3PO4. The highest conductivity was achieved with a 15 wt% MMT addition, with a dielectric-constant value of 74.9 at a frequency of 10 kHz.

Lithium titanate, Li4Ti5O12 (LTO) is a promising candidate as lithium ion battery anode material. In this investigation, LTO was synthesized by a solid state method using TiO2 xerogel prepared by the sol-gel method and lithium carbonate (Li2CO3). Three variations of Li2CO3 content addition in mol% or Li2CO3 molar excess were fabricated, i.e., 0, 50 and 100%, labelled as sample LTO-1, LTO-2 and LTO-3, respectively. The characterizations were made using XRD, FESEM, and BET testing. These were performed to observe the effect of lithium excess addition on structure, morphology, and surface area of the resulting samples. Results showed that the crystallite size and surface area of each sample was 50.80 nm, 17.86 m2/gr for LTO-1; 53.14 nm, 22.53 m2/gr for LTO-2; and 38.09 nm, 16.80 m2/gr for LTO-3. Furthermore, lithium excess caused the formation of impure compound Li2TiO3, while a very small amount of rutile TiO2 was found in LTO-1. A near-pure crystalline Li4Ti5O12 compound was successfully synthesized using the present method with stoichiometric composition with 0% excess, indicating very little Li+ loss during the sintering process.

Lithium phosphate (Li3PO4) is a promising candidate for solid electrolytes. However its ionic conductivity still stands at 3 × 10−7 S/cm which is very low compared to liquid electrolytes which are contained within widely distributed lithium ion batteries at 10−3 S/cm. This requires a solution to increase its conductivity which is the addition of dopants. The proposed dopants are lithium iodide (LiI) and lithium chloride (LiCl) which is mixed with the Li3PO4, creating the new solid electrolyte system Li3PO4(0.5)LiI(0.25)LiCl(0,25). The mixture had an ionic conductivity of 8 × 10−4 S/cm observed through electrochemical impedance spectroscopy (EIS). The crystal structure observation using x-ray diffraction identified the Li3PO4 belongs to the Hermann-Mauguinn symmetrical space group of P m n b.

SiOC@C is a lithium-ion battery (LIB) anode candidate that is expected to suppress the high volume expansion of Si by the presence of activated carbon as a buffer layer. Silicon oxycarbide (SiOC) was obtained from phenyl-rich silicone oil through pyrolysis at 900°C with flowing Ar gas. The variation of samples used were 4 and 10wt.% SiOC and a pure carbon sample was also prepared for comparison. SEM images show a porous microstructure with a few chunks of agglomerate present. According to Brunner-Emmet-Teller (BET) test, the largest surface area of 542.738 m2/g was obtained at 10wt.%SiOC. Based on the performance test result, the highest discharge capacity of 223.3 mAh/g was obtained at the mentioned prime condition.

A series of solid electrolytes based on natural polymer were prepared by mixing lithium triflate, (LiCF3SO3) into chitosan solutions of various compositions. The dielectric properties and conductivity behavior of as-cast and dried film were studied by using impedance spectrometer. The dielectric properties show that the dielectric loss (e′′) of both as-cast and dried film decreased with increasing frequency in the low frequency region followed by a peak. It was also found that the appearance of peaks for each sample in the loss tangent (tan δ) suggests the presence of relaxing dipoles in the polymer electrolyte films. In contrast with dried chitosan film, the tan δ peaks of the as-cast one shifted towards the higher frequency side with increasing lithium salt concentration, suggesting the speed-up of relaxation time. The AC conductivities of both samples showed the existence of a frequency-independent plateau region, which can be considered as DC conductivity. The DC conductivity of the as-cast sample, ho...

SYNTHESIS AND ELECTROCHEMICAL CHARACTERIZATION OF Li 3 PO 4 FORSOLID STATE ELECTROLYTES . The application of solid state electrolytes to solid state battery becomes important research area, recently, to overcome leakage and combustion issues involved in liquid electrolytes. Solid state electrolytes are safer, easily packaged and have several advantages, including easy fabrication, high ionic conductivity at room temperature and wide compositional range. Here in this study we characterized Li 3 PO 4 for solid state electrolyte, synthesized by solid state reaction and wet chemical reaction methods. The samples were characterized using Electrochemical Impedance Spectrometer (EIS) to determine its electrical properties in addition to X-Ray Diffraction and Scanning Electron Microscope -Energy Dispersive X-Rays Spectroscopy (SEM-EDS) characterizations. Both of samples that have been characterized have a high electrical resistivity on the order of tens MW, with DC conductivity in order of 10-10 to 10 -9 S/cm.

The solid electrolyte is of great interest owing to its potential to be applied in a wide variety of electrochemical devices. One of the most stable solid electrolytes is lithium phosphate (Li3PO4). However, this compound has low enough conductivity to be applied to a device such as an electrolyte. A previous study has reported that the mixture of xLi2O-P2O5, where x=2, has a greater conductivity than Li3PO4, while, when x=1, this yields an amorphous structure. In this study, new compositions of the xLi2O-P2O5 compounds, where 1?x?2, were prepared through solid-state reactions. The prepared compounds were characterized using X-ray Diffraction Spectrometry (XRD), Scanning Electron Microscopy (SEM), and Electrochemical Impedance Spectroscopy (EIS) measurements in order to investigate their structure, morphology, and electrochemical properties. The XRD characterization showed that both of the samples were composed mainly of Li4P2O7 crystals. Agglomeration of particles was observed in the samples. The conductivity of the compounds was of the order of 10?6 S/cm, which was higher by three orders of magnitude than that of Li3PO4. The evaluated power exponent of conductivity indicated that the long-range drift of ions may be one of the sources of ion conduction in both of the observed samples. The nature of the dielectric loss indicated that the conduction in the samples was more predominantly DC conduction.

Bahan elektrolit padat (Li2O)x(P2O5)y dengan komposisi konten Li2O sebesar x = 24 %berat dan 28 %berat telah dipreparasi menggunakan teknik reaksi padat pada suhu di bawah suhu lelehnya. Paduan yang telah dipreparasi kemudian dikarakterisasi menggunakan Scanning Electron Microscopy (SEM) dan Electrochemical Impedance Spectroscopy (EIS) untuk diperiksa morfologi, sifat elektrokimia dan konduktivitasnya. Karakterisasi elektrokimia menunjukkan bahwa nilai konduktivitas kedua paduan berada pada orde 10-6S/cm, setara dengan nilai konduktivitas paduan Li4P2O7 yang dipreparasi pada suhu lebih tinggi dengan kandungan Li2O lebih banyak, dan lebih tinggi dari konduktivitas senyawa Li3PO4. Taksiran nilai eksponen frekuensi dari formula konduktivitas AC, memperlihatkan bahwa kemungkinan sumber konduksi ion dalam bahan yang diamati salah satunya adalah aliran ion jarak jauh. Kurva rugi dielektrik menunjukkan bahwa konduksi dalam bahan elektrolit ini didominasi oleh konduksi DC.