Artur Tron

Surface Modification of the LiFePO4 Cathode for the Aqueous Rechargeable Lithium Ion Battery

The LiFePO4 surface is coated with AlF3 via a simple chemical precipitation for aqueous rechargeable lithium ion batteries (ARLBs). During electrochemical cycling, the unfavorable side reactions between LiFePO4 and the aqueous electrolyte (1 M Li2SO4 in water) leave a highly resistant passivation film, which causes a deterioration in the electrochemical performance. The coated LiFePO4 by 1 wt % AlF3 has a high discharge capacity of 132 mAh g-1 and a highly improved cycle life, which shows 93% capacity retention even after 100 cycles, whereas the pristine LiFePO4 has a specific capacity of 123 mAh g-1 and a poor capacity retention of 82%. The surface analysis results, which include X-ray photoelectron spectroscopy and transmission electron microscopy results, show that the AlF3 coating material is highly effective for reducing the detrimental surface passivation by relieving the electrochemical side reactions of the fragile aqueous electrolyte. The AlF3 coating material has good compatibility with the LiFePO4 cathode material, which mitigates the surface diffusion obstacles, reduces the charge-transfer resistances and improves the electrochemical performance and surface stability of the LiFePO4 material in aqueous electrolyte solutions.

Self-Assembled Novel BODIPY-Based Palladium Supramolecules and Their Cellular Localization

Four new palladium metal supramolecules with triangular/square architectures derived from boron dipyrromethane (BODIPY) ligands were synthesized by self-assembly and fully characterized by 1H and 31P NMR, electrospray ionization mass spectrometry, and single-crystal X-ray diffraction. These supramolecules were more cytotoxic to brain cancer (glioblastoma) cells than to normal lung fibroblasts. Their cytotoxicity to the glioblastoma cells was higher than that of a benchmark metal-based chemotherapy drug, cisplatin. The characteristic green fluorescence of the BODIPY ligands in these supramolecules permitted their intracellular visualization using confocal microscopy, and the compounds were localized in the cytoplasm and on the plasma membrane.

Polymeric binder based on PAA and conductive PANI for high performance silicon-based anodes

A novel polymeric binder, PAA–PANI, was prepared which effectively controls the uniformity of a Si anode. PANI provided electrical conductivity for this system, and furthermore participated in an acid–base interaction with PAA and as a result displayed remarkable mechanical properties. These electrical and mechanical properties together apparently led to PAA–PANI having yielded stable cycling and high utilization of the active Si material even after 300 cycles.

The Influence of Impurities in Room Temperature Ionic Liquid Electrolyte for Lithium Ion Batteries Containing High Potential Cathode

상온 이온성 액체인 propylmethylpyrrolidinium bis(trifluoromethanesulfonyl)imide (PMPyr-TFSI)를 리튬이차전지 전해질 용매로 사용 시 PMPyr-TFSI 내 수분 및 브롬 불순물이 전지의 성능에 미치는 영향을 연구하였다. 고전압 양극 물질인

Effect of Fluoroethylene Carbonate in the Electrolyte for LiNi 0.5 Mn 1.5 O 4 Cathode in Lithium-ion Batteries

LiNi_{0.5}Mn_{1.5}O_4

AlF3-coated LiMn2O4 as cathode material for aqueous rechargeable lithium battery with improved cycling stability

스피넬 구조 양극을 이용한 반쪽 전지의 전해질로 PMPyr-TFSI를 사용 하는데 있어, PMPyr-TFSI의 수분 함유량을 각각 12, 77, 1060 ppm으로 제어하고 전압 곡선 개형 및 쿨롱 효율 거동 추적을 통해 PMPyr-TFSI 수분량이 전지 성능에 부정적인 영향을 미치는 것을 구체적으로 확인하였다. 또한, PMPyr-TFSI 전해질 내의 브롬 이온 불순물 양 제어를 통하여, 전지 내에서 브롬 이온 불순물과 관련한 전기화학 부반응을 찾아 내었다. 이들 할로겐 불순물에 의한 초기 전지 쿨롱 효율저하는 눈에 띠었으나, 수명 저하에는 큰 변화가 없음을 확인하였다. 【We report the effect of the impurities including water and bromide in the propylmethylpyrrolidinium bis(trifluoromethanesulfonyl)imide (PMPyr-TFSI) on the electrochemical performance of lithium ion batteries. The several kinds of PMPyr-TFSI electrolytes with different amount of impurities are applied as the electrolyte to the cell with the high potential electrode,

Adsorptive Li+ mining from liquid resources by H2TiO3: Equilibrium, kinetics, thermodynamics, and mechanisms

LiNi_{0.5}Mn_{1.5}O_4

Physically cross-linked polymer binder based on poly(acrylic acid) and ion-conducting poly(ethylene glycol-co-benzimidazole) for silicon anodes

spinel. It is found that the impurities in the electrolytes cause the detrimental effect on the cell performance by tracing the cycleability, voltage profile and Coulombic efficiency. Especially, the polarization and Coulombic efficiency go to worse by both impurities of water and bromide, but the cycleability was not highly influenced by bromide impurity unlike the water impurity.】

Synthesis of the solid electrolyte Li2O–LiF–P2O5 and its application for lithium-ion batteries

Fluoroethylene carbonate (FEC) was studied as an additive for the electrolyte in lithium ion batteries with the LiNi0.5Mn1.5O4 (LNMO) spinel cathode operating at a high potential beyond 4.7 V (vs. Li/Li ). It was found that the FEC additive was electrochemically active for the 1 charge cycle on the LNMO cathode. The presence of a large amount of FEC (more than 40 vol%) in the electrolyte caused severe side reactions with abnormally long voltage plateaus. In contrast, when the electrolyte contained less than 30 vol% FEC , the surface of the LNMO cathode was stabilized by the formation of the solid-electrolyte interphase (SEI), leading to improved cyclability. However, the resistance from the SEI limited the rate capability because of sluggish lithium transportation through the SEI and electronic insulation between the particles