KAIST · Engineering
이 교수의 연구실은 리튬-황 배터리, 리튬-산소 배터리, 아연 기반 전지 등 고성능 이온 전지의 핵심 도전 과제인 전극 안정성, 전해질 부식, 불균일한 금속 리튬 도금 등을 해결하기 위한 전해질 설계와 나노구조 전극 개발에 집중하고 있습니다. 특히, 고기능성 전해질 설계를 통해 리튬 금속의 부식 문제를 완화하고, 전극 표면의 SEI 형성과 리튬 도금의 균일성을 제어함으로써 장수명 및 고성능 전지 시스템을 실현하고자 합니다. 또한, 아연 전지의 표면 반응 메커니즘과 산화환원 매개체의 안정화 기법을 통해 지속 가능한 에너지 저장 기술의 실현 가능성을 탐색하고 있습니다.
표시된 성과는 수집된 데이터 기준으로 산출되며, 일부 차이가 있을 수 있습니다.
Uncontrolled growth of insulating lithium sulfide leads to passivation of sulfur cathodes, which limits high sulfur utilization in lithium-sulfur batteries. Sulfur utilization can be augmented in electrolytes based on solvents with high Gutmann Donor Number; however, violent lithium metal corrosion is a drawback. Here we report that particulate lithium sulfide growth can be achieved using a salt anion with a high donor number, such as bromide or triflate. The use of bromide leads to ~95 % sulfur
A synergic combination of a soluble -redox mediator and a protected Li metal -electrode to prevent the self-discharge of the redox mediator is realized by -exploiting a 2,2,6,6-tetramethylpiperidinyl 1-oxyl (TEMPO) redox mediator and an Al2 O3 /PVdF-HFP composite -protective layer (CPL). Stabilization of Li metal by simple CPL coating is effective at -suppressing the chemical reduction of the oxidized TEMPO and opens up the possibility of sustainable redox mediation for robust cycling of Li-O2 b
The long-term cycling of anode-free Li-metal cells (i.e., cells where the negative electrode is in situ formed by electrodeposition on an electronically conductive matrix of lithium sourced from the positive electrode) using a liquid electrolyte is affected by the formation of an inhomogeneous solid electrolyte interphase (SEI) on the current collector and irregular Li deposition. To circumvent these issues, we report an atomically defective carbon current collector where multivacancy defects in
Highly reversible aqueous zinc anodes are demonstrated <italic>via</italic> suppressing surface diffusion of Zn adatoms from strong orbital hybridization of the Zn adatoms and single vacancy defects.
Abstract Engineering liquid electrolytes for lithium (Li)-metal electrodes has been used to control the morphology of deposited Li in Li-metal batteries (LMBs). However, the Li corrosion problem remains unresolved, hindering the design of lean electrolytes for practical LMBs, which require the electrolyte/capacity ( E / C ) ratio to be 2 g Ah −1 or lower. Here we report a borate–pyran-based electrolyte to address the chronic Li-corrosion problem. We discovered that the borate–pyran electrolyte t
Aqueous Zn-Br batteries (ZBBs) offer promising next-generation high-density energy storage for energy storage systems, along with distinctive cost effectiveness particularly in membraneless and flowless (MLFL) form. Unfortunately, they generally suffer from uncontrolled diffusion of corrosive bromine components, which cause serious self-discharge and capacity fade. An MLFL-ZBB is presented that fundamentally tackles the problem of bromine crossover by converting bromine to the polybromide anion
Abstract Minimizing electrolyte use is essential to achieve high practical energy density of lithium–sulfur (Li–S) batteries. However, the sulfur cathode is more readily passivated under a lean electrolyte condition, resulting in low sulfur utilization. In addition, continuous electrolyte decomposition on the Li metal anode aggravates the problem, provoking rapid capacity decay. In this work, the dual functionalities of NO 3 − as a high‐donor‐number (DN) salt anion is presented, which improves t
We conducted an objective comparison between the present performance and durability of AEMFCs with mature PEMFC technology. This review explains the pathway for AEMFCs by categorizing the materials, MEA designs, and various phenomena.
The laminated structure of graphene oxide (GO) membranes provides exceptional ion-separation properties due to the regular interlayer spacing ( d) between laminate layers. However, a larger effective pore size of the laminate immersed in water (∼11.1 Å) than the hydrated diameter of vanadium ions (>6.0 Å) prevents its use in vanadium redox-flow batteries (VRFB). In this work, we report an ion-selective graphene oxide framework (GOF) with a d tuned by cross-linking the GO nanosheets. Its effectiv
In this work, we present a 16 μm-thick Nafion-filled porous membrane for Zn/Br redox flow batteries (ZBBs). By using molecular dynamics simulation and dynamic light scattering analysis, we rationally design Nafion solution for Nafion impregnation into a porous polypropylene (PP) separator. A void-free Nafion/PP membrane is successfully fabricated by using NMP as a solvent for the Nafion solution. The resulting membrane shows a smaller area specific resistance in comparison with 600 μm-thick, com
