• Journal of Electrochemical Science and Technology
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• 제12권4호
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• pp.458-464
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• 2021

Lithium ion batteries (LIBs) is a kind of rechargeable secondary battery, developed from lithium battery, lithium ions move between the positive and negative electrodes to realize the charging and discharging of external circuits. Zeolitic imidazolate frameworks (ZIFs) are porous crystalline materials in which organic imidazole esters are cross-linked to transition metals to form a framework structure. In this article, ZIF-67 is used as a sacrificial template to prepare nano porous carbon (NPC) coated cobalt nanoparticles. The final product Co/NPC composites with complete structure, regular morphology and uniform size were obtained by this method. The conductive network of cobalt and nitrogen doped carbon can shorten the lithium ion transport path and present high conductivity. In addition, amorphous carbon has more pores that can be fully in contact with the electrolyte during charging and discharging. At the same time, it also reduces the volume expansion during the cycle and slows down the rate of capacity attenuation caused by structure collapse. Co/NPC composites first discharge specific capacity up to 3115 mA h/g, under the current density of 200 mA/g, circular 200 reversible capacity as high as 751.1 mA h/g, and the excellent rate and resistance performance. The experimental results show that the Co/NPC composite material improves the electrical conductivity and electrochemical properties of the electrode. The cobalt based ZIF-67 as the precursor has opened the way for the design of highly performance electrodes for energy storage and electrochemical catalysis.

• 공업화학
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• 제33권4호
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• pp.343-351
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• 2022

리튬이온 전지(lithium-ion batteries, LIBs)는 높은 에너지 밀도, 느린 자가방전율, 고율 충전 능력 및 긴 배터리 수명 등의 좋은 성능으로 촉망받는 에너지 저장 장치로 꼽힌다. 그러나 고에너지 밀도의 전기자동차 및 대형 디바이스 산업에서 이러한 LIBs의 적용은 큰 안전 문제를 일으키고 있다. 이러한 문제를 해결하기 위하여 열적 안정성 및 내재적 안전성이 높은 재료를 개발하는 것이 LIBs의 안정성 및 전기화학적 성능을 향상시키는 궁극적인 해결방법이다. 본 총설에서는 상용 분리막의 안정성 문제 극복을 위한 분리막의 표면 개질 기술을 소개하였으며 이를 이용하여 개질된 리튬이온 전지용 분리막을 활용한 연구 동향을 요약, 정리하였다. 또한 이를 기반으로 표면 개질에 따른 분리막에 대한 향후 전망을 논의하였다.

• Journal of Electrochemical Science and Technology
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• 제11권3호
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• pp.195-219
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• 2020

Today, rechargeable lithium-ion batteries are an essential portion of modern daily life. As a promising alternative to traditional energy storage systems, they possess various advantages. This review attempts to provide the reader with an indepth understanding of the working mechanisms, current technological progress, and scientific challenges for a wide variety of lithium-ion battery (LIB) electrode nanomaterials. Electrochemical thermodynamics and kinetics are the two main perspectives underlying our introduction, which aims to provide an informative foundation for the rational design of electrode materials. Moreover, both anode and cathode materials are clarified into several types, using some specific examples to demonstrate both their advantages and shortcomings, and some improvements are suggested as well. In addition, we summarize some recent research progress in the rational design and synthesis of nanostructured anode and cathode materials, together with their corresponding electrochemical performances. Based on all these discussions, potential directions for further development of LIBs are summarized and presented.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1998년도 춘계학술대회 논문집
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• pp.407-410
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• 1998

During the past decade, substantial research effort has been directed into the development of rechargeable lithium batteries. Although some improvements in cycle life and efficiency have been achieved, the reversibility of the lithium electrode remains as a significant problem in aprotic solvent based electrolyte. The major problems limiting cycle life are short circuits resulting from growth of lithium dendrites, and macroscopic shape changes during the recharge process. As an anode material of lithium rechargeable battery, amorphous carbon materials have been studied extensively because of their high electrochemical performance. The polyacene materials prepared from phenol refine at relatively low temperature(550∼750$^{\circ}C$) show a highly Li-doped state up C$_2$Li state without liberation of Li cluster. So it has largely layered distance 4${\AA}$. The Li storage mechanism as well as the large hysterisis observed in the voltage-capacity profile of the amorphous carbone materials are still the subjects of controversy. We prepared each polyacene material various temperature and investigated electrochemical property. The mole ratio of [H]/[C] is 0.027∼0.015 range.

• 세라미스트
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• 제21권4호
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• pp.406-415
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• 2018

Lithium ion batteries have been widely adopted as energy storage and the LIB global market has grown fastest. However, LIB players have struggled against maximizing energy density since commercial monolithic electrodes are limited by electrolyte depletion caused by long and tortuous Li-ion diffusion pathways. Recently, new strategies designing the structure of battery electrodes strive for creating fast Li-ion path and alleviating electrolyte depletion problem in monolithic electrodes. In this paper, given the fundamental and experimental approaches, we compare the monolithic to structured electrodes and demonstrate the ways to fabricate high energy, fast chargeable Lithium ion battery.

• 한국전기화학회:학술대회논문집
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• 한국전기화학회 1998년도 전지기술 심포지움
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• pp.153-166
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• 1998

Lithium ion Batteries commercially available since the early nineties in Japan are going to be more and more important for portable electronic devices and even EV applications. Today several companies around the world are working hard to join to market for Lithium secondary batteries. Based on the growing interest for commercial use of batteries also the materials have to be reviewed in order to meet large scale production needs. The requirements especially for electrolytes for lithium batteries are extremely high. The solvents and the lithium salts should be of highest purity. So the supply of these chemicals including packaging, transportation and storage but also the handling in production are critical items in this field. Frolic impurities are very critical for LiPF6 based electrolytes. The influence of water is tremendous. But also the other protic impurities like alcoholes are playing an Important role for the electrolyte quality. The reaction of these species with LiPF6 leads to formation of HF which further reacts with cathode materials (spinel) and anode. To understand the role of the protic impurities more clearly the electrolyte was doped with such compounds and was analyzed for protic impurities and HF. These results which directly show the relation between impurities and quality will be presented and discussed. In addition several investigations on different packaging materials as well as methods to analyze and handle the sensititive material will be addressed. These questions which are only partly discussed in literature so far and never been investigated systematically cover some of the key parameters for understanding of the battery chemicals. This investigation and understanding however is of major importance for scientist and engineers in the field of Lithium ion and Lithium polymer batteries.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 C
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• pp.1989-1991
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• 2005

Lithium titanium oxide as anode material for energy storage prepared by novel synthesis method. $Li_4Ti_5O_{12}$ based spinel-framework structures are of great interest material for lithium-ion batteries. We describe here $Li_4Ti_5O_{12}$ a zero-strain insertion material was prepared by novel sol-gel method and by high energy ball milling (HEBM) of precursor to from nanocrystalline phases. According to the X-ray diffraction and scanning electron microscopy analysis, uniformly distributed $Li_4Ti_5O_{12}$ particles with grain sizes of 100nm were synthesized. Lithium cells, consisting of $Li_4Ti_5O_{12}$ anode and lithium cathode showed the 173 mAh/g in the range of $1.0{\sim}3.0V$. Furthermore, the crystalline structure of $Li_4Ti_5O_{12}$ didn't transfer during the lithium intercalation and deintercalation process.

• 한국응용과학기술학회지
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• 제40권6호
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• pp.1191-1200
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• 2023

The lithium ion battery has applied to various fields of energy storage systems such as electric vehicle and potable electronic devices in terms of high energy density and long-life cycle. Despite of various research on the electrode and electrolyte materials, there is a lack of research for investigating of the binding materials to replace polymer based binder. In this study, we have investigated petroleum pitch/polymer composite with various ratios between petroleum pitch and polymer in order to optimize the electrochemical and physical performance of the lithium-ion battery based on petroleum pitch/polymer composite binder. The electrochemical and physical performances of the petroleum pitch/polymer composite binder based lithium-ion battery were evaluated by using a charge/discharge test, cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and universal testing machine (UTM). As a result, the petroleum pitch(MP-50)/polymer(PVDF) composite (5:5 wt % ratio) binder based lithium-ion battery showed 1.29 gf mm^-1 of adhesion strength with 144 mAh g^-1 of specific dis-charge capacity and 93.1 % of initial coulombic efficiency(ICE) value.

• 디지털산업정보학회논문지
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• 제12권3호
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• pp.231-257
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• 2016

Several efforts to replace the use of existing fossil energy resources have already been made around the world. As a result, a new industry of renewable energy has been created, and efficient energy distribution and storage has been promoted intensively. Among the newly explored renewable energy sources, the most widely used one is solar energy generation, which has a high market potential. An energy storage system (ESS) is a system as required. In this paper, the design and implementation of an ESS for the efficient use of power in stand-alone street lights is presented. In current ESS applied to stand-alone street lights, either 12V~24V DC (from solar power) or 110V~220V AC (from commercial power) is used to recharge power in systems with lithium batteries. In this study, an ESS that can support both solar power and commercial power was designed and implemented; it can also perform emergency recharge of portable devices from solar powered street lights. This system can maximize the scalability of ESSes using lithium batteries with efficient energy conversion, with the advantage of being an eco-friendly technology. In a ripple effect, it can also be applied to smart grids, electric vehicles, and new, renewable storage markets where energy storage technology is required.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.276-276
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• 2006

The incorporation of room temperature ionic liquids (IL) in poly (ethyleneoxide)-lithium salt (PEO-LiX) based solid polymer electrolytes is presently being studied as an effective means of enhancing the room temperature ionic conductivity of these electrolytes to acceptable levels for use in lithium batteries. In the present study, $PEO_{20}-LiTFSI$ solid polymer electrolyte was blended with three different ionic liquids, namely 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (BMIMTFSI), 1-butyl-3-methylimidazolium tetraflouroborate (BMIMBF4) and 1-butyl-3-methylimidazolium trifluromethanesulfonate ($BMIMCF_{3}SO_{3}$). The incorporation of all these ILs resulted in the enhancement of ionic conductivity, the effect being more pronounced at lower temperatures. Electrochemical properties of the blended electrolytes were studied by cyclic voltammetry, linear sweep voltammetry and interfacial resistance measurements. The optimum results were obtained with the blending of BMIMTFSI in the solid polymer electrolyte.