A New Concept on Resources Circulation Policy for Electric Vehicles in Korea (Republic of)

( Yong Choi ),( Hyeong-jin Choi ),( Sueng-whee Rhee ) 한국폐기물자원순환학회(구 한국폐기물학회) 2019 ISSE 초록집 Vol.2019 No.-

Globally, advanced countries will be prohibiting the sale of vehicles using internal combustion engine and promoting the supply of electric vehicles in order to reduce fine dust, air pollutants and carbon dioxide from vehicles. In Korea, 430,000 electric vehicles will be supplied by 2022 according to the atmospheric environmental policy. As the market for electric vehicles may be expanding at home and abroad, lithium ion secondary batteries from electric vehicles will be expected to be generated as wastes gradually. The lithium ion secondary batteries contain various valuable materials such as lithium, cobalt, manganese, nickel, iron, etc. According to Korea Mineral Resource Information Service (KOMIS), the price of lithium increased 2.1 times from 7,576 U$/ton in 2015 to 15,534 U$/ton in 2018. The price of cobalt increased 2.5 times from 28,613 U$/ton to 72,824 U$/ton during the same period. Therefore, it is industrially very economical that valuable materials are recovered from the lithium ion secondary battery. In advanced countries, various resources circulation policies are being used to recover and recycle lithium ion secondary batteries in electric vehicles. In the European Union and Japan, the lithium ion secondary batteries are managed by the Expanded Producer Responsibility (EPR) system and a recycling council was established to recycle the lithium ion secondary batteries continuously. Also, China announced regulations on the recycling of lithium ion secondary batteries for vehicles in 2015, strengthening resources circulation capacity for lithium ion secondary batteries. Electric vehicles are being promoted in Korea but the resources circulation policy for lithium ion secondary batteries is insufficient. In this study, the current status of resources circulation policy for lithium ion secondary batteries from electric vehicles in advanced countries is reviewed. In Korea, a new concept on the policy for the activation of resources circulation for lithium ion secondary battery should be introduced step by step including production, consumption, collection and recycling stage. The new concept of resources circulation policy can be applied in many fileds, including the securing of recycling technology, the construction of capacity build, and the establishment of management system such as EPR system.

리튬 이온 전지용 리튬 코발트 산화물 양극에서의 삽입 전압과 리튬 이온 전도

김대현,김대희,서화일,김영철,Kim, Dae-Hyun,Kim, Dae-Hee,Seo, Hwa-Il,Kim, Yeong-Cheol 한국전기화학회 2010 한국전기화학회지 Vol.13 No.4

본 연구는 밀도 범함수 이론을 이용하여 Li이온전지에 사용되는 Li코발트 산화물에서의 Li이온 삽입 전압과 전도에 관한 것이다. Li이온은 Li코발트 산화물 원자구조의 각 층을 1개씩 채우거나 한 층을 다 채우고 다음 층을 채울 수 있다. 평균 삽입 전압은 3.48V로 동일하나, 전자가 후자보다 더 유리하였다. 격자상수 c는 Li농도가 0.25보다 작을 때는 증가하였으나, 0.25보다 클 때는 감소하였다. Li농도가 증가하면, Li코발트 산화물에서의 Li이온 전도를 위한 에너지 장벽은 증가하였다. Li이온전지가 방전 중 출력 전압이 낮아지는 현상은 Li농도 증가에 따른 삽입 전압의 감소와 전도 에너지 장벽의 증가로 설명할 수 있었다. We performed a density functional theory study to investigate the intercalation voltage and lithium ion conduction in lithium cobalt oxide for lithium ion battery as a function of the lithium concentration. There were two methods for the intercalation of lithium ions; the intercalation of a lithium ion at a time in the individual layer and the intercalation of lithium ions in all the sites of one layer after all the sites of another layer. The average intercalation voltage was the same value, 3.48 V. However, we found the former method was more favorable than the latter method. The lattice parameter c was increased as the increase of the lithium concentration in the range of x < 0.25 while it was decreased as increase of the lithium concentration in the range of x > 0.25. The energy barrier for the conduction of lithium ion in lithium cobalt oxide was increased as the lithium concentration was increased. We demonstrated that the decrease of the intercalation voltage and increase of the energy barrier as the increase of the lithium concentration caused lower output voltage during the discharge of the lithium ion battery.

Improved performance of iron oxide nanoparticles embedded in nitrongen doped carbon for lithium ion battery anodes

( Jinaihua ),유승호,성영은 한국공업화학회 2015 한국공업화학회 연구논문 초록집 Vol.2015 No.1

Efficient energy storage devices with an extended lifetime are required to meet the increasing energy demands in various fields such as electronics, as well as for renewable energy generation systems and electric vehicles. Lithium ion batteries (LIBs) have attracted great attention as one of the most dominant power sources because of their high power and energy densities. In commercial industry, graphite was used as lithium ion batteries anode. However, graphite already approaches very close to the limited theoretical capacity (372 mA h g^-1) and graphite cannot satisfy the demand of high capacity storage. Therefore, many studies are focused on improving the specific capacity of LIB anode materials. Transition-metal oxides have been studied for use as anode materials due to their high specific capacity. Fe₃O₄ is one of them and the theoretical capacity is 924 mA h g^-1. Nitrogen doping of carbonaceous materials has been studied as an effective way to improve the electrochemical performance. In particular, nitrogen doping of carbon-based materials allows for enhanced interaction with lithium ions and the creation of a great number of active sites. Fe₃O₄ was synthesized by particularly simple way and exhibited improved electrochemical performance when they were employed as anode materials for lithium ion batteries. Fe₃O₄ nanoparticles embedded in nitrogen doped carbon show the reversible capacity as high as 700 mA h g^-1 over 100 cycles at current density of 200 mA h g^-1 in lithium ion batteries applications.

리튬 이온 배터리의 가스 발생 특성에 대한 연구

이준혁(Joon-Hyuk Lee),홍성호(Sung-Ho Hong),이흥수(Heung-Su Lee),박문우(Moon-Woo Park) 한국화재소방학회 2021 한국화재소방학회논문지 Vol.35 No.5

리튬이온배터리 화재 및 폭발의 주요 원인 중 하나는 배터리에서 발생하는 가연성 가스이며, ESS와 같이 배터리 다수가 밀집된 경우 열폭주 및 화재 전이로 인한 위험성이 크다. 이에 따라 국내·외에서 리튬이온배터리의 가스 발생 및열폭주 현상을 예측하고 예방하기 위한 연구가 다수 진행되고 있으나 아직 현재진행형인 실정이다. 따라서, 본 연구에서는 리튬이온배터리 열폭주 전후에 발생하는 가스를 분석하여 열폭주로 인한 위험을 경감시킬 수 있는 기반을 마련하고자 한다. 발생 되는 가스의 종류 및 특성 등을 파악하여 열폭주 시 조기 감지에 의한 예방의 토대를 구축하는 것이다. 실험을 위해 리튬이온배터리를 외관별(원통형, 각형, 파우치형), 양극재별(NCM, NCA, LFP)로 구분하였고 가로, 세로,높이가 각 1.5 m인 챔버 내에서 리튬이온배터리에 열적 이상 조건을 가하여 시간별로 발생하는 가스를 측정하였다. 가스 측정을 위해 FT-IR 분석장치를 사용하였으며, 별도의 수소 센서를 챔버 내에 설치하여 리튬이온전지의 시간별 가스종류 및 측정량 변화를 분석하였다. 실험 결과, 모든 리튬이온배터리에서 CO2와 CO가 가장 많이 발생 되었다. 열폭주이후 각형 및 파우치형에서는 CO2는 증가하고 CO가 감소하였으며, 원통형에서는 CO2와 CO 모두 증가하였다. 독성가스인 HF와 폭발범위가 넓은 H2 또한 발생되었으며, 두 가스의 농도는 상호 간 반비례 관계를 나타냈다. A main cause of fires and explosions in lithium-ion batteries is the generation of combustible gases by them, and whena large number of batteries are densely packed, like in an Energy Storage System, there is a high risk of thermal runawayand fire propagation. Currently, many studies are being conducted worldwide to predict and prevent the generation ofcombustible gases, and thermal runaway in lithium-ion batteries, but they are still in progress. Therefore, in this study, weanalyzed the gases generated before and after thermal runaway in lithium ion batteries, to prepare a basis for reducing therisk of thermal runaway. We aimed to establish the basis for prevention by early detection in the event of thermal runaway,by understanding the type and characteristics of the generated gases. For the experiment, lithium ion batteries were classifiedin terms of appearance (cylindrical, prismatic, pouch type), and cathode materials (NCM, NCA, LFP). The gases generatedwas measured against time. An FT-IR analyzer was used for gas measurement, and a separate hydrogen sensor was installedin the chamber to analyze changes in the types of gas, and measure the mass of the lithium ion battery over time. In theexperiment, CO2 and CO were generated the most during thermal runaway in all lithium-ion batteries. Thereafter, CO2increased, and CO decreased in the prismatic and pouch types, and both CO2 and CO increased in the cylindrical type. HF(a toxic gas), and H2 having a wide explosive range, were also generated, and the concentrations of these gases were inverselyproportional to each other.

공랭식 원통형 리튬-이온 배터리 팩의 공기 흐름 변화에 따른 냉각 시스템 성능에 관한 수치해석 연구

이서근(SeoKeun Lee),심창휘(ChangHwi Sim),김철호(Chul-Ho Kim) 한국자동차공학회 2020 한국자동차공학회 학술대회 및 전시회 Vol.2020 No.11

친환경자동차인 전기자동차의 동력원으로 에너지 밀도가 높은 리튬-이온 배터리가 주목을 받고 있다. 리튬-이온 배터리는 낮은 자가 방전율과 양호한 내구 수명 등 많은 장점을 지니고 있는 반면 온도의 변화에 따라 배터리 셀의 효율이 변화되며 특정 환경조건에서는 열 폭주 현상이 발생하는 등 안전성 측면의 문제가 제기되고 있으며 배터리 셀의 효율적 냉각과 셀간 온도 밸런스가 중요한 문제로 대두되고 있는 상황이다. 본 연구에서는 21700모델의 원통형 리튬-이온 셀을 적용한 공냉식 배터리 팩 모델을 대상으로 냉각 유로방향에 따른 배터리 팩의 냉각 성능과 셀 간의 온도 밸런스 특성을 분석해 보았다. 일반적으로 리튬-이온 배터리 팩은 원통형 셀이 정방향으로 반복적으로 균일하게 반복 배열되는 형태를 유지하고 있으며 연구의 편의성을 위해 이중 일부인 배터리 셀 7개의 구조를 대상으로 발열량이 일정하다는 정상상태로 연구를 진행하였다. 정상상태의 열유동해석을 위해 상용 CFD코드인 영국 CHAM사의 PHOENICS(ver.2018)를 이용하였다. 주요 연구 변수로 냉각 공기의 흐름 방향과 유량 그리고 셀의 간격을 설정하였으며 배터리 팩의 냉각 성능과 셀의 온도 분포를 분석하여 셀간 온도 밸런스를 정성, 정량적으로 분석하였다. 배터리 간격은 총 8가지 경우로 분석하였으며 셀의 온도는 3곳을 기준으로 판단하였으며 온도차이가 확연한 구간을 중심으로 간격을 설정하였다. 온도 밸런스 측면에서 균일도는 배터리 길이방향이 8.86%, 직경방향은 15.43%로 길이 방향이 직경 방향에 비해 6.57%p의 균일도 차이를 보였다. 본 연구를 통해 유체의 흐름 방향과 배터리 셀 간격이 냉각 성능에 미치는 영향을 정량적으로 분석하였으며 적정한 간격과 흐름 방향을 제시함으로써 향후 리튬-이온 배터리 팩의 최적화 냉각 연구에 기여할 것으로 기대된다. Lithium-ion batteries with high energy density are drawing attention as power sources for electric vehicles, which are eco-friendly vehicles. Lithium-ion batteries have many advantages, such as low self-discharge rates and good durable life, while the efficiency of battery cells varies depending on temperature and the heat explosion occurs under certain environmental conditions, raising safety issues. Therefore, efficient cooling of lithium-ion battery cells and temperature balancing between cells are becoming important issues. In this study, the cooling performance of battery packs along the flow direction and the temperature-balancing characteristics between cells were analyzed in the air-cooled battery pack models with cylindrical lithium-ion cells of 21700 models. In general, lithium-ion battery packs were studied in a steady state that the cylindrical cells were kept in a uniform, repetitive arrangement in the forward direction and that the heat value was constant in seven structures of battery cells, which are part of a pack, for the convenience of the study. A general purpose CFD simulation program named PHOENICS (ver. 2018) which is developed by CHAM, England was used. The flow rate, direction and spacing of cooling air and battery spacing were set as major research variables, and the cooling performance of battery pack and temperature distribution of cells were analyzed in a qualitative and quantitative analysis of temperature balancing between cells. The effect of battery space was analyzed with a total of eight cases, and the temperature was determined based on three points of cells. The interval was set around the area where the temperature difference was evident. In terms of temperature balance, the uniformity was 0.83% in the direction of battery height and 15.43% in the direction of diameter, showing 14.6% difference in between. Through this study, it is expected to contribute to the study of battery pack cooling by quantitatively analyzing the flow direction of fluid and the effect of battery cell space on cooling performance.

리튬이차전지 양극 소재 성능 향상을 위한 최신 기술 동향 및 연구 전망

박서현 ( Seohyeon Park ),오필건 ( Pilgun Oh ) 한국화상학회 2021 한국화상학회지 Vol.27 No.2

본 논문에서 리튬이온전지용 양극 소재의 개발 동향과 함께 앞으로 필요한 양극 소재의 연구 방향을 제시한다. 현재 리튬이온 전지는 지구 환경 개선을 위한 친환경 에너지로 주목받고 있으며, 전기차와 에너지저장 시스템 등에서의 다양한 활용으로 고용량 및 고안정성 소재 개발에 초점을 맞추어 연구가 진행되고 있다. 특히, 리튬이온전지 양극 소재의 경우 전지의 가격 및 성능을 결정하기 때문에 활발한 연구가 이루어지며, 그중 높은 이론 용량을 가지는 Ni-rich 계 layered 구조의 양극 소재에 대한 연구가 집중되고 있다. 그러나, 고용량 특성을 달성하기 위한 Ni-rich 계 양극 소재는 높은 Ni 조성에 의해 비용량이 증가함에 따라 전기화학적 불안정성 또한 증가하는 문제를 가지기 때문에 활용에 한계를 가진다. 이를 해결하기 위한 방법으로 본 논문에서는 양극 소재의 표면 개질 방법과 원소치환 방법에 대해 언급하며, 이에 진일보하여 리튬이온전지의 가격 경쟁력을 확보하기 위한 양극 소재의 연구 방향을 제안한다. This study presents the development trends of cathode materials in lithium-ion batteries and the future research direction of cathode materials. Currently, lithium-ion batteries have been focused on improving the global environment, and research of lithium-ion batteries continues to concentrate on increasing the capacity and stability as lithium-ion battery application focus moves towards electric vehicles and energy storage systems. The study of cathode materials is considered important in determining the property and cost of lithium-ion batteries. Among such studies, researchers have concentrated on layered structure cathode materials with a high theoretical capacity. However, applying Ni-rich cathodes as a means to achieve high capacity has limited utilization because the high Ni composition in cathode materials causes increasing electrochemical instability during the charge process. In order to solve this problem, this study presents the ideas about the research method of surface modification and atomic substitution, suggesting a novel future research direction for cathode materials to ensure the price competitiveness of lithium-ion batteries.

자체 제작된 리튬이온 배터리팩의 과충전에 따른 화재위험성 연구

한용택,김일원,김시국 한국위험물학회 2022 한국위험물학회지 Vol.10 No.1

Lithium-ion battery packs are used in various electronic devices such as camping batteries, electric kickboard, and supplementary battery due to their high volumetric energy storage density. Recently, however, as more and more people make and use outdoor lithium-ion battery packs such as hiking, fishing, and camping, there is a battery fire while charging their own battery packs. This paper investigated the operating principle of these battery packs and conducted a study on the fire risk caused by overcharging in the presence or absence of lithium-ion batteries with the same capacity, lithium-ion batteries with different capacity, and PCM(Protection Circuit Module). As a result of the overcharging experiment, the battery pack was completely destroyed combustible gas and smoke generation near the lithium-ion battery anode of the battery pack without a protection circuit, followed by explosive combustion accompanied by flame. Vent and safety devices(PTC, CID) could be observed to have been lost due to overcharging explosion pressure.

Sn/SnO_x-loaded uniform-sized hollow carbon spheres on graphene nanosheets as an anode for lithium-ion batteries

Lee, Jeongyeon,Hwang, Taejin,Oh, Jiseop,Kim, Jong Min,Jeon, Youngmoo,Piao, Yuanzhe Elsevier 2018 JOURNAL OF ALLOYS AND COMPOUNDS Vol.736 No.-

<P><B>Abstract</B></P> <P>To meet the increasing demands for large-scalable application required high capacity and energy density, Sn-based materials as a promising anode for lithium-ion batteries have been widely studied. In this work, a carbon nanostructure of uniform-sized hollow carbon spheres on a graphene nanosheet was prepared by a facile synthesis process. The obtained nanostructure has numerous uniform-sized hollow carbon spheres with a diameter of ∼20 nm attached on graphene nanosheets, and mass production is considerably easy. Then, Sn/SnO<SUB>x</SUB> was loaded into the carbon nanostructure by a typical melt diffusion process, and its electrode delivers the high rate capability of 290.0 mA g<SUP>−1</SUP> at 3.0 A g<SUP>−1</SUP> and the good cyclability of 284.1 mA h g<SUP>−1</SUP> after 1000 cycles at 1.0 A g<SUP>−1</SUP>. The excellent electrochemical performance is attributed to the unique carbon nanostructure, which mitigates the volume expansion of Sn by the physical barrier of uniform-sized hollow carbon spheres and enables Li-ions or electrons to easily move by the improving electrical conductivity during discharge/charge process. Thus, the Sn loaded nanocomposite is expected to be a promising anode material for lithium-ion batteries.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A strategy is established for the synthesis of hollow carbon spheres on graphene nanosheets. </LI> <LI> The hollow carbon spheres were used as Sn/SnO<SUB>x</SUB> hosts for lithium ion battery. </LI> <LI> The carbon nanostructure could mitigate the volume expansion of Sn during the cycling. </LI> <LI> The electrode delivers an excellent reversible capacity even after 1000 cycles. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>Sn/SnO<SUB>x</SUB>-loaded uniform-sized hollow carbon spheres on graphene nanosheets is fabricated from a facile solventless method and delivers good cycle ability for lithium-ion batteries.</P> <P>[DISPLAY OMISSION]</P>

리튬이온 배터리 동특성 및 안전성 평가를 위한 배터리 시뮬레이터 시험설비

정성인,윤용호,Sungin Jeong,Yongho Yoon 한국인터넷방송통신학회 2024 한국인터넷방송통신학회 논문지 Vol.24 No.2

Lithium-ion batteries are used in many fields due to their high energy density, fast charging conditions, and long cycle life. However, overcharging, over-discharging, physical damage, and use of lithium-ion batteries at high temperatures can reduce battery life and cause damage to people due to fire or explosion due to damage to the protection circuit. In order to reduce the risk of these batteries and improve battery performance, the characteristics of the charging and discharging process must be analyzed and understood. Therefore, in this paper, we analyze the charging and discharging characteristics of lithium-ion batteries using a battery charger and discharger and simulator to reduce the risk of loss of life due to overcharge and overdischarge, as well as casualties from fire and explosion due to damage to the protection circuit.

2D layered Sb₂Se₃-based amorphous composite for high-performance Li- and Na-ion battery anodes

Nam, Ki-Hun,Park, Cheol-Min Elsevier 2019 Journal of Power Sources Vol.433 No.-

<P><B>Abstract</B></P> <P>A two-dimensional layered Sb<SUB>2</SUB>Se<SUB>3</SUB>-based amorphous composite (<I>a</I>–Sb<SUB>2</SUB>Se<SUB>3</SUB>/C) is synthesized using a simple solid-state ball-milling process, and its potential for Li- and Na-ion batteries is evaluated. <I>Ex situ</I> extended X-ray absorption fine structure analyses clearly indicate the electrochemical reaction mechanisms of Sb<SUB>2</SUB>Se<SUB>3</SUB> and <I>a</I>–Sb<SUB>2</SUB>Se<SUB>3</SUB>/C as anodes for Li- and Na-ion batteries. During Li- and Na-insertion, the Sb<SUB>2</SUB>Se<SUB>3</SUB> and <I>a</I>–Sb<SUB>2</SUB>Se<SUB>3</SUB>/C electrodes are converted into the final phases of Li<SUB>3</SUB>Sb/Na<SUB>3</SUB>Sb and Li<SUB>2</SUB>Se/Na<SUB>2</SUB>Se, respectively. During Li- and Na-extraction, the Li<SUB>3</SUB>Sb/Na<SUB>3</SUB>Sb and Li<SUB>2</SUB>Se/Na<SUB>2</SUB>Se in the Sb<SUB>2</SUB>Se<SUB>3</SUB> electrode are converted into Sb and Se, showing a non-recovery reaction, whereas a recovery to the original Sb<SUB>2</SUB>Se<SUB>3</SUB> in the <I>a</I>–Sb<SUB>2</SUB>Se<SUB>3</SUB>/C electrode occurs after full Li and Na extraction. Owing to the interesting conversion/recovery reaction, the <I>a</I>–Sb<SUB>2</SUB>Se<SUB>3</SUB>/C electrode exhibits excellent electrochemical performance, such as high reversible capacities (Li-ion battery: 662 mAh g<SUP>−1</SUP>; Na-ion battery: 407 mAh g<SUP>−1</SUP>), a long cycle life with highly reversible capacities (Li-ion battery: 662 mAh g<SUP>−1</SUP> and 1,205 mAh cm<SUP>−3</SUP>, respectively, after 100<SUP>th</SUP> cycle; Na-ion battery: 378 mAh g<SUP>−1</SUP> and 688 mAh cm<SUP>−3</SUP>, respectively, after 50<SUP>th</SUP> cycle), and high rate capabilities (Li-ion battery: 623 mAh g<SUP>−1</SUP> and 1,133 mAh cm<SUP>−3</SUP> at 3C; Na-ion battery: 270 mAh g<SUP>−1</SUP> and 492 mAh cm<SUP>−3</SUP> at 2C).</P> <P><B>Highlights</B></P> <P> <UL> <LI> A layered Sb<SUB>2</SUB>Se<SUB>3</SUB> and its amorphous Sb<SUB>2</SUB>Se<SUB>3</SUB>/C composite is synthesized simply. </LI> <LI> The reaction mechanisms during Li- and Na-insertion/extraction is demonstrated. </LI> <LI> The Sb<SUB>2</SUB>Se<SUB>3</SUB> had conversion/non-recovery reactions during Li- and Na-reactions. </LI> <LI> The Sb<SUB>2</SUB>Se<SUB>3</SUB>/C had conversion/full-recovery reactions during Li- and Na-reactions. </LI> <LI> The amorphous Sb<SUB>2</SUB>Se<SUB>3</SUB>/C exhibited excellent electrochemical performances. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>