• The Transactions of the Korean Institute of Power Electronics
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• v.27 no.3
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• pp.265-274
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• 2022

This paper proposes a machine learning-based screening algorithm to build the retired battery pack of the energy storage system. The proposed algorithm creates the dataset of various performance parameters of the retired battery, and this dataset is preprocessed through a principal component analysis to reduce the overfitting problem. The retried batteries with a large deviation are excluded in the dataset through a density-based spatial clustering of applications with noise, and the K-means clustering method is formulated to select the group of the retired batteries to satisfy the deviation requirement conditions. The performance of the proposed algorithm is verified based on NASA and Oxford datasets.

• Journal of the Korean Chemical Society
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• v.67 no.3
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• pp.165-174
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• 2023

The development of all-solid-state batteries (ASSBs) has been gaining attention in recent years due to their potential to offer higher energy densities, improved safety, and longer cycle life compared to conventional lithium-ion batteries. However, several challenges must be addressed to achieve the practical application of ASSBs, such as the development of high-performance solid-state electrolytes, stable electrode-electrolyte interfaces, and cost-effective manufacturing processes. In this review paper, we present an overview of the current state of ASSB research, including recent progress in solid-state electrolyte and cathode/anode materials, and cell architecture. We also summarize the recent advancements and highlight the remaining challenges in ASSB research, with an outlook on the future of this promising technology.

• Journal of Ceramic Processing Research
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• v.13 no.spc2
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• pp.304-307
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• 2012

Nano-fibers of LiFePO4 were synthesized from a metal oxide precursor by adopting electrospinning method. After calcination of the above precursor nano-fibers at 800 ℃, LiFePO4 nano-fibers with a diameter of 300 ~ 800 nm, were successfully obtained. Measurement were performed using X-ray diffraction (XRD), fourier transform infrared spectrometer (FT-IR), videoscope, scanning electron microscope (SEM) and atomic force microscope (AFM), respectively, were performed to characterize the properties of the as-prepared materials. The results showed that the crystalline phase and morphology of the fibers were largely influenced the starting materials and electrospinning conditions.

• Proceedings of the KIPE Conference
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• 2020.08a
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• pp.209-211
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• 2020

운송기관의 온실가스 저감을 위해 배터리-수소연료전지 하이브리드 철도추진시스템에 대한 연구가 활발히 진행되고 있다. 이 중 배터리는 빠른 응답 특성으로 하이브리드 철도추진 시스템의 효율을 극대화 시키기 위해 주요 전원으로 사용되고 있어, 시스템의 안전성 및 신뢰성을 높이기 위해 정확한 열화추정이 요구되고 있다. 본 논문에서는 사전 모델의 수립이 필요하지 않고 미소 용량 및 폐회로 제어가 가능한 재귀 최소제곱 추정 기법을 이용한 리튬이온 배터리의 SOH 추정 기법을 제안하였으며, 1S18P 배터리 모듈을 통해 열화 추정결과를 검증하였다.

• Proceedings of the KIPE Conference
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• 2020.08a
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• pp.127-129
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• 2020

높은 에너지 밀도, 장 수명 등의 특성을 갖는 리튬계열 축전지는 다양한 어플리케이션에 활용되고 있다. 그러나, 리튬계열 축전지의 열화로 인한 출력 특성 저하는 원전 사고 시, 안정적인 전력 공급을 저해하므로 원전 적용을 위해서 리튬계열 축전지의 열화를 일으키는 방사선에 대한 리튬계열 축전지의 강건성 검토가 필요하다. 본 논문은 방사성 동위원소 Co-60, 총 방사선량 100Gy의 저 준위 방사선 조사 시험을 진행하였으며, 이에 따른 리튬계열 축전지의 특성 비교를 위해서 전기적 특성분석 방법을 이용하였다.

• Proceedings of the KIPE Conference
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• 2020.08a
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• pp.124-126
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• 2020

다양한 기기에 적용된 리튬 이온 전지의 출력은 전력으로 계산되며, 리튬 이온 전지는 전류 기반의 해석뿐만 아니라 전력기반의 해석 또한 필수적이다. 본 논문은 리튬 이온 전지의 정전력 입력과 출력에 따른 전류 관점의 분석과 전력 관점의 분석을 수행하였다. 리튬 이온 전지에서 정전력 입력 및 출력 시, 충전 상태와 에너지 상태 변화의 차이를 및 용량과 에너지 변화를 분석하였다.

• Applied Chemistry
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• v.16 no.1
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• pp.73-76
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• 2012

Due to the developments of communications equipment and electronic devices, lithium ion secondary battery usage is growing. Along with demand increasing, the amount of scrap has been steadily increasing. In this study, method of cobalt recovery using organic eco-friendly is proposed. Sulfuric acid, Malic acid, Citric acid at reflux device had good cobalt leaching efficiency. And Sulfuric acid, Malic acid at the autoclave increased cobalt leaching efficiency.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.37 no.1
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• pp.11-25
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• 2024

Lithium-ion batteries (LIBs) have attracted great attention as the common power source in energy storage fields of large-scale applications such as electrical vehicles (EVs), industries, power plants, and grid-scale energy storage systems (ESSs). Insertion, alloying, and conversion reactions are the main electrochemical energy storage mechanisms in LIBs, which determine their electrochemical properties and performances. The electrochemical reaction mechanisms are determined by several factors including crystal structure, components, and composition of electrode materials. This article reviews a new strategy to compensate for the intrinsic shortcomings of each reaction mechanism by introducing the material systems to form a single compound with different types of reaction mechanisms and to allow the simultaneous hybrid electrochemical reaction of two different mechanisms in a single solid solution phase.

• Elastomers and Composites
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• v.58 no.4
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• pp.201-207
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• 2023

Owing to their unique properties originating from slidable cross-links, polyrotaxane derivatives have potential applications as polymer electrolytes for lithium-ion batteries, lightweight polymer alloys for vehicular bodies and their glazing, elastic rubbers for tires, hydrogels for drug delivery. This article reviews the structures of polyrotaxanes comprising cyclic molecules threaded by a linear axle polymer. Next, the versatile characteristics of polyrotaxane gels, elastomers, and polymer alloys such as toughness, elasticity, and softness are discussed in relation to their supramolecular architectures. Finally, the mechanical behavior of solid ring cross-links are compared with that of conventional fixed cross-links for better understanding.

• Asian Journal of Innovation and Policy
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• v.12 no.3
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• pp.345-362
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• 2023

As the widespread adoption and proliferation of electric vehicles continue, the secondary battery market is experiencing rapid growth. However, lithium-ion batteries, which constitute a majority of secondary batteries, present high risks of fire and explosion. Solid-state batteries are thus garnering attention as the next-generation batteries since they eliminate fire hazards and significantly reduce the risk of explosions. Against this background, the study aimed to analyze research trends and provide insights by examining 2,927 domestic papers related to solid-state batteries over the past decade (2013-2022). Specifically, we used topic modeling to extract major keywords associated with solid-state batteries research and to explore the network characteristics across major topics. The changes in research on solid-state batteries were analyzed in-depth by calculating topic dominance by year. The findings provide an overview of the emerging trends in domestic solid-state battery research, and might serve as a valuable reference in shaping long-term research directions.