리튬이온배터리는 높은 에너지 저장 효율과 환경 지속 가능성으로 점점 더 많은 관심을 받고 있다. PU 기반 리튬이온배터리에 사용되는 기존의 고분자 (polyurethane, PU) 바인더는 높은 유연성과 기 계적 강도를 제공하여 전극의 부피 변화를 감소시키고 구조적 안정성을 확보하는데 효과적이지만, 이와같 은 고분자 계열의 바인더는 전기전도도가 낮고 생산 및 폐기 과정에서 환경 문제를 야기할 수 있다. 따라 서, 본 연구에서는 이러한 고분자계 바인더의 단점을 해결하고자 고분자계 바인더로 많이 사용되는 PU 기 반 리튬이온배터리에 비해 향상된 전기화학적 성능과 안정성을 가진 새로운 바인더로서 석유계 피치 (SM260)/고분자 (polyurethane, PU) 복합소재 기반 바인더를 개발하였다. 특히, PU 바인더가 적용된 리튬 이온배터리는 100 사이클 후 가역 용량이 80 mAh/g으로, 초기 용량의 25%의 용량 유지율을 나타낸 반면, 본 연구에서 개발한 석유계 피치 (SM260)/고분자 (polyurethane, PU) 복합소재 복합 바인더가 적용된 리 튬이온배터리는 100 사이클 후 가역용량이 208 mAh/g으로 유지되고, 초기 용량의 68% 용량 유지율을 나 타내었다.

The demand for secondary batteries is increasing rapidly with the popularization of electric vehicles and the expansion of wireless electronic devices. However, the most widely used lithium-ion batteries are subject to frequent fire incidents, limiting market growth. To avoid flammability, solid electrolyte-based systems are gaining attention for next-generation lithium-ion batteries. However, challenges such as limitations in ionic conductivity and high manufacturing costs require further research and development. In this study, we aim to identify a new nitrogen-based solid electrolyte material that has not yet been widely explored. We propose a methodology for selecting the final material through high-throughput screening (HTS), detailing the methods used for material selection and performance evaluation. In addition, we present ab initio molecular dynamics (AIMD) calculations and results for nitrogen-substituted materials with carbon and oxygen replacements, including Arrhenius plots, activation energy, and the predicted conductivity at 300K for the material with the highest Li-ion conductivity. While the performance does not yet surpass the ionic conductivity and activity of conventional solid-state electrolytes, our results provide a systematic framework for exploring and screening new solid electrolyte materials. This methodology can also be applied to the exploration of different battery materials and is expected to contribute significantly to the innovation of next-generation energy storage technologies.

Iron selenides with high capacity and excellent chemical properties have been considered as outstanding anodes for alkali metal-ion batteries. However, its further development is hindered by sluggish kinetics and fading capacity caused by volume expansion. Herein, a series of FeSe2 nanoparticles (NPs)-encapsulated carbon composites were successfully synthesized by tailoring the amount of Fe species through facile plasma engineering and followed by a simple selenization transformation process. Such a stable structure can effectively mitigate volume changes and accelerate kinetics, leading to excellent electrochemical performance. The optimized electrode ( FeSe2@C2) exhibits outstanding reversible capacity of 853.1 mAh g− 1 after 150 cycles and exceptional rate capacity of 444.9 mAh g− 1 at 5.0 A g− 1 for Li+ storage. In Na+ batteries, it possesses a relatively high capacity of 433.7 mAh g− 1 at 0.1 A g− 1 as well as good cycle stability. The plasma-engineered FeSe2@ C2 composite, which profits from synergistic effect of small FeSe2 NPs and carbon framework with large specific surface area, exhibits remarkable ions/electrons transportation abilities during various kinetic analyses and unveils the energy storage mechanism dominated by surface-mediated capacitive behavior. This novel cost-efficient synthesis strategy might offer valuable guidance for developing transition metal-based composites towards energy storage materials.

Si-based anodes are promising alternatives to graphite owing to their high capacities. However, their practical application is hindered by severe volume expansion during cycling. Herein, we propose employing a carbon support to address this challenge and utilize Si-based anode materials for lithium-ion batteries (LIBs). Specifically, carbon supports with various pore structures were prepared through KOH and NaOH activation of the pitch. In addition, Si was deposited into the carbon support pores via SiH4 chemical vapor deposition (CVD), and to enhance the conductivity and mechanical stability, a carbon coating was applied via CH4 CVD. The electrochemical performance of the C/Si/C composites was assessed, providing insights into their capacity retention rates, cycling stability, rate capability, and lithium-ion diffusion coefficients. Notably, the macrostructure of the carbon support differed significantly depending on the activation agent used. More importantly, the macrostructure of the carbon support significantly affected the Si deposition behavior and enhanced the stability by mitigating the volume expansion of the Si particles. This study elucidated the crucial role of the macrostructure of carbon supports in optimizing Si-based anode materials for LIBs, providing valuable guidance for the design and development of high-performance energy-storage systems.

In this study, carbon coating was carried out by physical vapor deposition (PVD) on SiOx surfaces to investigate the effect of the deposited carbon layer on the performance of lithium-ion batteries as a function of the asphaltene content of petroleum residues. The petroleum residue was separated into asphaltene-free petroleum residue (ASF) and asphaltene-based petroleum residue (AS) containing 12.54% asphaltene by a solvent extraction method, and the components were analyzed. The deposited carbon coating layer became thinner, with the thickness decreasing from 15.4 to 8.1 nm, as the asphaltene content of the petroleum residue increased, and a highly crystalline layer was obtained. In particular, the SiOx electrode carbon-coated with AS exhibited excellent cycling performance with an initial efficiency of 85.5% and a capacity retention rate of 94.1% after 100 cycles at a current density of 1.0 C. This is because the carbon layer with enhanced crystallinity had sufficient thickness to alleviate the volume expansion of SiOx, resulting in stable SEI layer formation and enhanced structural stability. In addition, the SiOx electrode exhibited the lowest resistance with a low impedance of 23.35 Ω, attributed to the crystalline carbon layer that enhanced electrical conductivity and the mobility of Li ions. This study demonstrated that increasing the asphaltene content of petroleum residues is the simplest strategy for preparing SiOx@C anode materials with thin, crystalline carbon layers and excellent electrochemical performance with high efficiency and high rate performance.

In this study, ester co-solvents and fluoroethylene carbonate (FEC) were used as low-temperature electrolyte additives to improve the formation of the solid electrolyte interface (SEI) on graphite anodes in lithium-ion batteries (LIBs). Four ester co-solvents, namely methyl acetate (MA), ethyl acetate, methyl propionate, and ethyl propionate, were mixed with 1.0 M LiPF6 ethylene carbonate:diethyl carbonate:dimethyl carbonate (1:1:1 by vol%) as the base electrolyte (BE). Different concentrations were used to compare the electrochemical performance of the LiCoO2/ graphite full cells. Among various ester co-solvents, the cell employing BE mixed with 30 vol% MA (BE/MA30) achieved the highest discharge capacity at − 20 °C. In contrast, mixing esters with low-molecular-weight degraded the cell performance owing to the unstable SEI formation on the graphite anodes. Therefore, FEC was added to BE/MA30 (BE/MA30-FEC5) to form a stable SEI layer on the graphite anode surface. The LiCoO2/ graphite cell using BE/MA30-FEC5 exhibited an excellent capacity of 127.3 mAh g− 1 at − 20 °C with a capacity retention of 80.6% after 100 cycles owing to the synergistic effect of MA and formation of a stable and uniform inorganic SEI layer by FEC decomposition reaction. The low-temperature electrolyte designed in this study may provide new guidelines for resolving low-temperature issues related to LIBs, graphite anodes, and SEI layers.

To improve the lithium-ion battery performance and stability, a conducting polymer, which can simultaneously serve as both a conductive additive and a binder, is introduced into the anode. Water-soluble polyaniline:polystyrene sulfonate (PANI:PSS) can be successfully prepared through chemical oxidative polymerization, and their chemical/mechanical properties are adjusted by varying the molecular weight of PSS. As a conductive additive, the PANI with a conjugated double bond structure is introduced between active materials or between the active material and the current collector to provide fast and short electrical pathways. As a binder, the PSS prevents short circuits through strong π‒π stacking interaction with active material, and it exhibits superior adhesion to the current collector, thereby ensuring the maintenance of stable mechanical properties, even under high-speed charging/discharging conditions. Based on the synergistic effect of the intrinsic properties of PANI and PSS, it is confirmed that the anode with PANI:PSS introduced as a binder has about 1.8 times higher bonding strength (0.4 kgf/20 mm) compared to conventional binders. Moreover, since active materials can be additionally added in place of the generally added conductive additives, the total cell capacity increased by about 12.0%, and improved stability is shown with a capacity retention rate of 99.3% even after 200 cycles at a current rate of 0.2 C.

With the emergence of the new energy field, the demand for high-performance lithium-ion batteries (LIBs) and green energy storage devices is growing with each passing day. Carbon nanotubes (CNTs) exhibit tremendous potential in application due to superior electrical and mechanical properties, and the excellent lithium insertion properties make it possible to be LIBs anode materials. Based on the lithium insertion mechanism of CNTs, this paper systematically and categorically reviewed the design strategies of CNTs-based composites as LIBs anode materials, and summarized in detail the enhancement effect of CNTs fillers on various anode materials. More importantly, the superiorities and limitations of various anode materials for LIBs were evaluated. Finally, the research direction and current challenges of the industrial application of CNTs in LIBs were prospected.

Lithium-ion batteries are widely used in various advanced devices, including electric vehicles and energy storage devices. As the application range of lithium-ion batteries expands, it will be increasingly important to improve their gravimetric and volumetric energy density. Layer-structured oxide materials have been widely adopted as cathode materials in Li-ion batteries. Among them, LiNiO2 has attracted interest because of its high theoretical capacity, ~274 mAh g-1, assuming reversible one Li+-(de)intercalation from the structure. Presently, such layered structure cathode materials are prepared by calcination of precursors. The precursors are typically hydroxides synthesized by coprecipitation reaction. Precursors synthesized by coprecipitation reaction have a spherical morphology with a size larger than 10 μm. Spherical precursors in the several micrometer range are difficult to obtain due to the limited coprecipitation reaction time, and can lead to vigorous collisions between the precursor particles. In this study, spherical and small-sized Ni(OH)2 precursors were synthesized using a new synthesis method instead of the conventional precipitation method. The highest capacity, 170 mAh g-1, could be achieved in the temperature range of 730~760 °C. The improved capacity was confirmed to be due to the higher quality of the layered structure.

Silicon-based anode materials have attracted significant interest because of their advantages, including high theoretical specific capacity (~4,200 mAh/g), low working potential (0.4 V vs Li/Li+), and abundant sources. However, their significant initial capacity loss and large volume changes during cycling impede the application of silicon-based anodes in lithium-ion batteries. In this work, we propose a silicon oxide (SiOx) anode material for lithium-ion batteries produced with a magnesio-thermic reduction (MTR) process adopting Boryeong mud as a starting material. Boryeong mud contains various minerals such as clinochlore [(Mg,Fe)6(Si,Al)4O10(OH)8], anorthite (CaAl2Si2O8), illite [K0.7Al2(Si,Al)4O10(OH)2], and quartz (SiO2). The MTR process with Boryeong mud generates a mixture of amorphous silicon oxides (SiOx and SiO2), and magnesium aluminate which helps to alleviate the volume expansion of the electrode during charge/discharge. To observe the effects of these oxides, we conducted various analyses including X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier-Transformation infrared spectroscopy (FT-IR), Brunauer-Emmett-Teller (BET) and cyclic voltammetry (CV) galvanic cell testing. The amorphous SiO2 and MgAl2O4 suppressed the volume expansion of the silicon-based anode, and excellent cycle performance was achieved as a result.

탄소중립을 달성하기 위해 이산화탄소를 포집, 활용, 저장하는 CCUS (carbon capture, utilization, and storage) 기 술이 주목받고 있다. 본 연구에서는 광물 탄산화 공정을 통해 이산화탄소를 탄산염으로 고정하고, 이를 전이금속 탄산염 기반 리튬이온배터리 (LIB) 음극재로 적용하였다. CO2를 탄산염으로 고정후, 이를 이용해 FeCO3를 제작하고, rGO와 PVP와 복합 화하여 음극활물질에 적용하였다. rGO는 전기전도도를 높이고 입자의 응집을 방지해 부피 팽창을 완화했으며, PVP는 계면 활성제로서 입자 표면을 안정화하여 구조적 안정성을 강화하였다. FeCO3-PVP-rGO 복합체 기반한 음극재에 대한 전기화학 테스트를 진행한 결과, FeCO3/rGO 복합체는 1,620 mA/g의 전류 밀도에서 50 사이클 이후에도 400 mAh/g의 용량을 유지하 였다. 본 연구는 CO2를 고부가가치 배터리 소재로 전환하여 차세대 에너지 저장 기술에 기여할 가능성을 시사한다.

에너지 저장 장치의 필수 요소인 리튬에 대한 필요성이 증가함에 따라 전 세계 리튬 침전물의 주요 공급원인 염 수로부터 효율적인 리튬 회수 방법의 개발이 요구됩니다. 염수로부터 리튬을 회수하는 과정은 유사한 특성을 가진 공존하는 이온의 존재로 인해 복잡합니다. 크라운 에테르 기능화된 막은 선택적 리튬 회수를 위한 유망한 솔루션을 제시합니다. 이온- 쌍극자 상호 작용을 통한 금속 이온에 대한 강한 친화력으로 유명한 크라운 에테르는 공동-이온 크기 호환성에 기반한 리튬 이온의 선택적 추출을 촉진하는 “호스트-게스트” 복합체를 형성합니다. 다양한 연구에서 크라운 에테르 이식된 막이 리튬 선 택성을 향상시키는 데 효과가 있음이 입증되었습니다. 이 리뷰는 크라운 에테르 기능화된 막의 발전을 탐구하여 염수로부터 의 리튬 회수 문제를 해결할 수 있는 잠재력을 보여줍니다.

리튬이온전지는 친환경적이고 우수한 전지 성능덕분에 배터리 산업의 핵심으로 자리 잡았으며, 이에 따라 수요가 급증하고 있다. 그러나, 리튬이온전지의 수요증가는 리튬과 광물자원들의 공급문제를 초래하며, 수명이 다한 폐 리튬이온전지의 폐기방안이 아직 마련되지 않아 환경적 문제를 발생시킨다. 이러한 문제를 해결하기 위해 폐 리튬이온전지를 재활용하는 연구가 진행되고 있으며, 그 중에서도 폐 리튬이온전지에서 폐 양극 소재를 추출하여 재활용하는 다이렉트 리사이클링 연구가 주목받고 있다. 그러나, 폐 양극 소재는 오랜 충/방전으로 인해 구조적 붕괴(열화)가 발생한 상태로, 새로운 리튬이온전지에 적용을 위해서는 리튬이온전지 사용 전의 구조 즉, 층상구조로의 회복이 필요하다. 본 연구에서는 이를 위해 폐 양극 소재(LiNi0.6C0.2Mn0.2O2)가 열역학적으로 층상구조를 형성하는 온도를 분석하기 위해 700 ºC, 800 ºC, 900 ºC 범위에서 XRD를 통해 구조분석을 진행하였다. 폐 양극 소재는 700 ºC와 900 ºC 대비 800 ºC 열처리 시 1.44로 가장 높은 I003/I104 value를 보였다. 또한 800 ºC 열처리 시 0.1 C 기준 비 용량이 171.3 mAh/g으로 가장 높은 것을 확인하였다. 이를 통해 우리는 열역학적으로 층상구조를 형성하는 온도를 800 ºC로 도출하였으며 폐 양극 소재의 구조를 성공적으로 복원하였다.

Graphene has been extensively investigated as a host material for Li metal anodes owing to its light weight, high electrical conductivity, high surface area, and exceptional mechanical rigidity. Many studies have focused on assembling twodimensional (2D) graphene sheets into three-dimensional (3D) forms, such as lamination, spheres, and carbon nanotubes; however, little attention has been paid to the technology of modifying 2D graphene sheets. Herein, nanoperforated graphene (NPG) was fabricated through a relatively straightforward process employing metal oxide catalysts based on aqueous solutions. Nanoperforations exhibited a size of approximately 5 nm and were introduced on the graphene sheet and lithiophilic carbonyl groups (C = O) at the edges, facilitating the rapid diffusion of Li+ and lowering the Li nucleation overpotential. In comparison to the reduced graphene oxide (RGO) host, the NPG host exhibited a lower lithium nucleation overpotential and a stable overpotential of ~ 30 mV for over 150 cycles as a stable host structure as a Li metal anode for Li metal batteries.

Mesocrystals are macroscopic structures formed by the assembly of nanoparticles that possess distinct surface structures and collective properties when compared to traditional crystalline materials. Various growth mechanisms and their unique features have promise as material design tools for diverse potential applications. This paper presents a straightforward method for metal–organic coordination-based mesocrystals using nickel ions and terephthalic acid. The coordinative compound between Ni2+ and terephthalic acid drives the particle-mediated growth mechanism, resulting in the mesocrystal formation through a mesoscale assembly. Subsequent carbonization converts mesocrystals to multidirectional interconnected graphite nanospheres along the macroscopic framework while preserving the original structure of the Ni-terephthalic acid mesocrystal. Comprehensive investigations demonstrate that multi-oriented edge sites and high crystallinity with larger interlayer spacing facilitate lithium ion transport and continuous intercalation. The resulting graphitic superparticle electrodes show superior rate capability (128.6 mAh g− 1 at 5 A g− 1) and stable cycle stability (0.052% of capacity decay per cycle), certifying it as an advanced anode material for lithium-ion batteries.

All-solid-state lithium batteries (ASSLBs) are receiving attention as a prospective next-generation secondary battery technology that can reduce the risk of commercial lithium-ion batteries by replacing flammable organic liquid electrolytes with non-flammable solid electrolytes. The practical application of ASSLBs requires developing robust solid electrolytes that possess ionic conductivity at room temperature on a par with that of organic liquids. These solid electrolytes must also be thermally and chemically stable, as well as compatible with electrode materials. Inorganic solid electrolytes, including oxide and sulfide-based compounds, are being studied as promising future candidates for ASSLBs due to their higher ionic conductivity and thermal stability than polymer electrolytes. Here, we present the challenges currently facing the development of oxide and sulfide-based solid electrolytes, as well as the research efforts underway aiming to resolve these challenges.

In this study, we report significant improvements in lithium-ion battery anodes cost and performance, by fabricating nano porous silicon (Si) particles from Si wafer sludge using the metal-assisted chemical etching (MACE) process. To solve the problem of volume expansion of Si during alloying/de-alloying with lithium ions, a layer was formed through nitric acid treatment, and Ag particles were removed at the same time. This layer acts as a core-shell structure that suppresses Si volume expansion. Additionally, the specific surface area of Si increased by controlling the etching time, which corresponds to the volume expansion of Si, showing a synergistic effect with the core-shell. This development not only contributes to the development of high-capacity anode materials, but also highlights the possibility of reducing manufacturing costs by utilizing waste Si wafer sludge. In addition, this method enhances the capacity retention rate of lithium-ion batteries by up to 38 %, marking a significant step forward in performance improvements.

The raw material selected for this research was Brazil chestnut shells (BCs), which were utilized to gain porous carbon as a positive electrode for lithium–sulfur batteries (LSBs). The effects of N/S co-doped on the electrochemical properties of porous carbon materials were studied using thiourea as nitrogen and sulfur sources. The experimental results indicate that the N/S co-doped carbon materials have a higher mesopore ratio than the undoped porous carbon materials. The porous carbon material NSPC-2 has a lotus-like structure with uniform pore distribution. The N and S doping contents are 2.5% and 5.4%. The prepared N/S co-doped porous carbon materials were combined with S, respectively, and three kinds of sulfur carbon composites were obtained. Among them, the composite NSPC-2/S can achieve the initial specific discharge capacity of 1018.6 mAh g− 1 at 0.2 C rate. At 1 C rate, the initial discharge capacity of the material is 730.6 mAh g− 1, and the coulomb efficiency is 98.6% and the capacity retention rate is 71.5% after 400 charge–discharge cycles.

Electric-propulsion systems for ships, also known as electric propulsion devices, represent the current direction of development for maritime power. Issues concerning the environment and fuel economy have compelled the maritime transport sector to seek solutions that reduce emissions and improve fuel efficiency. In this process, power electronics technology plays a significant role in the propulsion systems of ships. Selecting an efficient battery system is of great importance for enhancing the cruising range of yachts and minimizing environmental impact. The battery model is crucial for revealing the working principles of batteries, and it is extremely critical for the application and development of battery technology. The Battery Management System (BMS) serves a crucial regulatory function, optimizing both the safety and performance of battery cells. Central to its operation is the precise estimation of the battery's State of Charge (SOC), a process dependent on an exacting battery model. This system not only enhances longevity and reliability but also ensures that energy storage solutions meet high standards of efficacy. This study focused on testing the impedance characteristics of lithium-sulfur batteries (LSB) at various SOC points and establishing first- and second-order RC equivalent circuit models. The model parameters were identified through experimental data. Subsequently, a simulation platform was constructed using MATLAB/Simulink to simulate the behavior of LSB under a constant current discharge condition. The simulation results showed that the second-order RC model had significantly lower errors than the first-order model, demonstrating higher accuracy. These achievements can provide technical support for the research of energy storage systems in the green aviation and maritime industries.