Soo Chan Kim

BACKGROUND: Wearable trackers can help motivate you during workouts and provide information about your daily routine or fitness in combination with your smartphone without requiring potentially disruptive manual calculations or records. This paper summarizes and compares wearable fitness devices, also called "fitness trackers" or "activity trackers." These devices are becoming increasingly popular in personal healthcare, motivating people to exercise more throughout the day without the need for

Abstract Although Li–S batteries are currently receiving great interest, due to their high energy density and the low cost of sulfur, practical applications are still inhibited by capacity fading that is caused by various undesirable processes. In this study, a new multifunctional network binder composed of chitosan and reduced graphene oxide (rGO) is introduced to enhance the capacitive performance of Li–S batteries. Chitosan is reacted with graphene oxide in aqueous solution to produce a homog

The lithium–sulfur battery is one of the most promising “beyond Li-ion” battery chemistries owing to its superior gravimetric energy density and low cost. Nonetheless, its commercialization has been hindered by its low cycle life due to the polysulfide shuttle and nonuniform Li-metal plating and stripping. Thin and dense solid electrolyte separators could address these issues without compromising on energy density. Here, we introduce a novel argyrodite (Li6PS5Cl)–carboxylated nitrile butadiene r

Abstract A high‐performance Li–Se battery is demonstrated by adopting a novel Se cathode design. The Se cathode is a one‐piece body combined with a Se deposited current collector and a solid polymer electrolyte (SPE). In the preparation of the Se cathode, Se is electrodeposited on Ni‐foam, and the pores are filled with SPE layers. Through this electrodeposition, the cathode is easily fabricated, and charge transports are facile. The use of the SPE layer offers a durable Se electrode, enhancing i

Abstract Li–S batteries have attracted considerable interest as next-generation energy storage devices owing to high energy density and the natural abundance of sulfur. However, the practical applications of Li–S batteries are hampered by the shuttle effect of soluble lithium polysulfides (LPS), which results in low cycle stability. Herein, a functional interlayer has been developed to efficiently regulate the LPS and enhance the sulfur utilization using hierarchical nanostructure of C 3 N 4 ( t

Anode-free Li-ion batteries (AFBs), where a Cu current collector is used to plate and strip Li instead of a classic anode, are promising technologies to increase the energy density of batteries. In addition, AFBs are safer and easier to manufacture than competing Li-metal anodes and solid-state batteries. However, the loss of Li inventory that occurs during the operation of AFBs limits their lifespan and practical application. In this study, we find that, in particular, the current density used

We proposed the mouse to control a computer mouse with head rotations and eye blinks so that the severe disabled person can use a computer. We compared the performance of the proposed mouse to that of a general computer mouse and to that of alternative mouses such as Quick glance using eye movements and a Camera mouse using face movements. The mouse positions were estimated using gyro sensors that can measure the angular velocity of head rotations, and mouse events such as clicks/double clicks w

Abstract Next‐generation energy storage devices such as lithium–sulfur batteries (LSBs) face several challenges including fast charging and high‐power delivery. Thus, it is necessary to improve the stability of the electrodes with efficient electrochemical system. In this work, a durable sulfur cathode even at high rates is enabled via lean binder content. The binder consists of a chitosan cross‐linked with a carboxylated nitrile–butadiene rubber (XNBR), which exhibits high affinity toward lithi

The synthesis and electrocatalytic performance of iridium-oxide (IrO2) are reported. IrO2 was electrochemically deposited on the gold dendrite template prepared by the chronoamperometry. The influence of the synthetic condition on the morphology, phase composition, and accessible surface area of the IrO2 dendrites was investigated. The optimized IrO2 dendrites showed an excellent electrocatalytic activity toward oxygen evolution with a low overpotential of 240 mV at 5 mAcm−2 and to the sensing o

Abstract Separators are crucial in lithium‐sulfur batteries (LiSBs) to ensure optimal ion transport and prevent internal short circuits. High‐performance separators with excellent thermal stability, electrolyte wettability, porosity, and Li + selectivity are essential for the safety and enhancing the energy density of LiSBs. This is particularly important for mitigating polysulfide (LiPS) shuttling, which degrades both the capacity and cycling stability of LiSBs. In this work, a novel separator