Nano-meter scaled evaluation for dynamic behavior of lithium ions in a micro secondary battery embedded in silicon substrate

在这个项目中，我们对嵌在硅衬底上的微型二次电池中锂离子的动态行为进行了纳米尺度的评估。为此，用原子力显微镜和导电探头同时观察了镶嵌在硅衬底上的全固态锂二次电池((Al/Li/SiO_2-15at%P_2O_5/LiMn_2O_4/polycrystalline硅)5×5μm^2区域的表面形貌和充放电特性。电池面积为5×5μm^2的充放电行为对应于~2.9×10^&lt；10&gt；Li^+离子/μm^2的运动，反映了Li^+离子的循环运动。铝电极由0.1~1.5μm的鳞片状颗粒组成，在第一次充电时上升约30 nm。铝电极表面随着充放电的进行，呈现出由鳞片状到皱纹状的周期性变化，表明阳极中多余的锂被吸进了玻璃电解液中。这些结果对…来说是有希望的此外，我们还研究了锂离子在尖晶石LiMn_2O_4正极中的动力学行为。为此，用原子力显微镜和电导探针研究了锂离子二次电池的典型正极材料尖晶石LiMn2O4的3.5x3.5μm^2区域的表面形貌。在从LiMn2O4中提取Li+离子的负偏压下，电流在5.5V处突然增大，表明Li+离子向表面传导。对应于电流的增加，覆盖整个表面的部分鳞片状颗粒膨胀和扁平，表明Li累积层中的Mn-Eg和O-2p电子之间的排斥作用导致了Jahn-Teller相变。此外，还研究了新型固体电解质材料Li_3AlN_2和正极材料LiCoO_2的光电性能。为了制作100×100μm^2尺寸的全固态电池，在硅衬底上制作了尺寸为100μm×100μm×2μm的隔离孔。在未来，我们将尝试在微米尺寸的孔中嵌入100×100μm^2尺寸的电池的准备工作。较少

In this project, we pursued nano-meter scaled evaluation for the dynamic behavior of lithium ions in a micro secondary battery embedded in silicon substrate. For this purpose, surface morphology and charge/discharge characteristic in a 5×5 μm^2 area of an all-solid-state Li secondary battery (Al/Li/SiO_2-15at%P_2O_5/LiMn_2O_4/polycrystalline silicon) embedded in a Si substrate are simultaneously observed by atomic force microscopy (AFM) with a conductive probe. The battery area of 5×5 μm^2 shows charge/discharge behavior corresponding to the movement of 〜2.9×10^<10> Li^+ ions/μm^2, reflecting the cyclic movement of Li^+ ions. The Al electrode consisting of scale-shaped grains of 0.1〜1.5 μm in size rises by 〜30 nm during the first charge operation. The surface of the Al electrode shows a cyclic change from scaly to wrinkled structures with the charge/discharge operations, indicating the drawing of the excess Li in the anode into the glassy electrolyte. These results are promising for th … More e realization of a micrometer-sized battery.Furthermore, we also studied the dynamic behavior of lithium ions in spinel-LiMn_2O_4 cathode. For this purpose, surface morphology in 3.5×x3.5 μm^2 area of spinel LiMn_2O_4, which is a typical cathode,material for Li ion secondary batteries, is studied using an atomic force microscopy (AFM) with a conductive probe. Under the negative bias voltage to extract Li^+ ions from LiMn_2O_4, electric current abruptly increases at 5.5 V, indicating Li^+ ionic conduction toward the surface. Corresponding to the increase in current, part of scale shaped grains covering the whole surface expand and flatten, suggesting the Jahn-Teller phase transition induced by the repulsive interaction between the Mn-eg and O-2p electrons in Li accumulated layer. Additionally, optical and electronic properties of a new solid state electrolyte material Li_3AlN_2 and a cathode material LiCoO_2 were studied. In order to fabricate 100×100 μm^2 sized all solid state batteries, isolated holes of 100 μm×100 μm× 2 μm in size were made in Si substrates. In the future, we will try the preparation for the 100×100 μm^2 sized batteries embedded in the mico-meter sized holes. Less