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All-solid-state lithium-ion batteries (ASSLBs) represent a promising breakthrough in battery technology owing to their high energy density and exceptional stability. When crafting cathode electrodes for ASSLBs, the solid electrolyte/cathode material interface is physically hindered by the specific morphology of carbon additive materials. In this paper, we examine the distribution of conductive additives within the electrode and its impact on the electrochemical performance of composites incorporating either nano-sized carbon black (CB) or micron-sized carbon nanofibers (CNF) into Ni-rich (LiNi0.8Co0.1Mn0.1O2) cathode material based composites. When nano-sized CB is employed as a conductive additive, it enhances the electrical conductivity of the composite by adopting a uniform distribution. However, its positioning between the solid electrolyte and cathode material leads to an increase in interfacial resistance during charge and discharge cycles, resulting in decreased electrochemical performance. In contrast, using micron-sized CNF as a conductive additive results in a reduction in the composite's electrical conductivity compared to CB. Nevertheless, due to the comparatively uninterrupted interfaces between the solid electrolyte and cathode materials, it exhibits superior electrochemical characteristics. Our findings are expected to aid the fabrication of electrochemical-enhanced cathode composite electrodes for ASSLBs. [ABSTRACT FROM AUTHOR]

In this study, multi-walled carbon nanotubes (MWCNTs) were modified by thermal fluorination to improve dispersibility between MWCNTs and Li4Ti5O12 (LTO) and were used as additives to compensate for the disadvantages of LTO anode materials with low electronic conductivity. The degree of fluorination of the MWCNTs was controlled by modifying the reaction time at constant fluorination temperature; the clear structure and surface functional group changes in the MWCNTs due to the degree of fluorination were determined. In addition, the homogeneous dispersion in the LTO was improved due to the strong electronegativity of fluorine. The F-MWCNT conductive additive was shown to exhibit an excellent electrochemical performance as an anode for lithium ion batteries (LIBs). In particular, the optimized LTO with added fluorinated MWCNTs not only exhibited a high specific capacity of 104.8 mAh g−1 at 15.0 C but also maintained a capacity of ~116.8 mAh g−1 at a high rate of 10.0 C, showing a capacity almost 1.4 times higher than that of LTO with the addition of pristine MWCNTs and an improvement in the electrical conductivity. These results can be ascribed to the fact that the semi-ionic C–F bond of the fluorinated MWCNTs reacts with the Li metal during the charge/discharge process to form LiF, and the fluorinated MWCNTs are converted into MWCNTs to increase the conductivity due to the bridge effect of the conductive additive, carbon black, with LTO. [ABSTRACT FROM AUTHOR]

The abundant use of lithium-ion batteries (LIBs) in a wide variety of electric devices and vehicles will generate a large number of depleted batteries, which contain several valuable metals, such as Li, Co, Mn, and Ni, present in the structure of the cathode material (LiMO2). The present work investigates the extraction of lithium, as lithium chloride, from spent LIBs by carbochlorination roasting. The starting samples consisted of a mixture of cathode and anode materials from different spent LIBs known as black mass. Calcium chloride was used as a chlorinating agent, and carbon black was used as a reducing agent. The black mass, calcium chloride, and carbon black were mixed in 50:20:30 w/w % proportions. Non-isothermal thermogravimetric tests up to 850 °C and isothermal tests at 350, 500, and 700 °C were carried out in an inert atmosphere. It was observed that the carbochlorination reaction starts at 500 °C. An extraction percentage of 99% was attained through carbochlorination at 700 °C. The characterization results indicate that CaCO3, Ni, and Co and, to a lesser extent, CoO, NiO, and MnO2 are present in the roasted sample after the processes of washing, filtering, and drying. [ABSTRACT FROM AUTHOR]

In this study, novel CuIn 2 S 4 (CIS) material is synthesized through a hydrothermal technique. The as-prepared materials are characterized the structural, chemical and electrochemical properties. The electrochemical performance is evaluated by utilizing as a novel anode material for Li-ion storage. The pristine CuIn 2 S 4 material used cell exhibits Li-ion reversible capacities of 349 and 176 mAh g−1 at the current densities of 0.2 and 1 A g−1, respectively. Furthermore, to improve the electrochemical performance of pristine CIS modified with carbon black (CIS/C) through high-energy ball-milling technique. The resultant CIS/C composite shows an improving reversible discharge capacity of 717 mAh g−1 at 0.2 A g−1 and 591 mAh g−1 at 1 A g−1, respectively. Moreover, the CIS/C composite preserves a high discharge capacity of 376 mAh g−1 over 500 cycles without cyclic decay at 5 A g−1. Additionally, the ex-situ XRD and cyclic voltammetry (CV) analyses expose a Li-ions stored into CIS via conversion reaction mechanism. Overall, this work indicates that the novel material utilization of energy storage device and improvement of storage performance for future high-energy Li and post Li-ion batteries applications. [Display omitted] • CuIn 2 S 4 and CuIn 2 S 4 /C are applied for Li-Ion storage anode for the first-time. • The Li-ion storage mechanism is proposed through CV and ex-situ XRD analyses. • The CIS/C electrode cell exposed better electrochemical performance than bare CIS. • CIS/C composite preserves a high discharge capacity of 376 mAh g−1 over 500 cycles at 5 Ag−1. [ABSTRACT FROM AUTHOR]

Conductive carbon additives play very important roles on the performance of Li-ion batteries (LIBs) although they only occupy a very small mass percentage in both cathode and anode. Building up a multidimensional carbonaceous conductive network on cathode with the optimized mass ratio of carbon black, carbon nanotubes (CNTs) and graphene has been verified to be able to enhance the Li-ion storage performance. Herein, we further demonstrate that applying ternary conductive additives is also very effective in improving the rate and cycle performances of graphite anode although the active material already possess high electronic conductivity. A conductive additive assembly of 2 wt% Super P, 1 wt% CNTs and 1 wt% graphene can weave up an efficient conducting pathway on the mesocarbon microbeads (MCMB) anode and enhance the cycle stability (344 mAh g−1 at 1 C after 200 cycles) and rate performance (226 mAh g−1 at 3 C). The coin-type full cell assembled with the optimized MCMB anode and NCM811 cathode also displays much improved rate capability and cycle stability. As is revealed, the multidimensional conducting network might has led to a more uniform and ion conductive SEI film on MCMB anode, which lowers the polarization and energy barrier for Li+ transportation. [Display omitted] • A multidimensional conducting network is constructed on MCMB anode by modifying the dispersion solvent. • A specific capacity of 344 mAh g−1 is preserved after 200 cycles at 1 C. • The multidimensional conducting network promotes the Li+ transfer in MCMB anode. • Using ternary conductive additives in graphite anode is a practical way to improve the performance of LIBs. [ABSTRACT FROM AUTHOR]

The mechanism of non-stoichiometric MnCo 2 O 4+δ to stoichiometric MnCo 2 O 4 structural transformation in the calcination temperature range of 350–650 °C and its morphology evolution from nanoplates with {112} facets to quasi nanoplates with {110} facets in the preferential orientation of [220] direction is investigated in detail and confirmed using XPS, HRTEM, TGA, and XRD analysis. By having a profound understanding of this mechanism, MnCo 2 O 4 with a well-controlled structure and morphology was synthesized via co-precipitation as the anode for Li-ion batteries to overcome the capacity fading issue. Moreover, the anode microstructure was optimized based on the correlation between Li+ storage, electrode durability, and interfacial resistance through the electrochemical response of electrode components, including MnCo 2 O 4 , carbon black, and binder. The optimum electrode exhibited a high initial discharge capacity of 2063 mAh g−1 at 400 mA g−1, excellent rate capability (807 mAh g−1 at 1000 mA g−1), and outstanding cycling performance (709 mAh g−1 at 400 mA g−1 after 150 cycles). These are attributed to the balance between the high surface area and robust architecture of MnCo 2 O 4 , and the stability, conductivity, and porosity of the electrode. [Display omitted] • Phase studies show that increasing the temperature to 650 °C resulted in the evacuation of excess oxygen in MnCo 2 O 4+δ. • By increasing the temperature, {112} facets alter to {110} facets in the preferential orientation of [220] direction. • The optimized electrode exhibited a stable reversible capacity of 709.5 mAh g−1 over 150 cycles at 400 mA g−1. [ABSTRACT FROM AUTHOR]

Novel core-shell structure hard carbon/Si-carbon composites are prepared, and their electrochemical performances as an anode material for lithium-ion batteries are reported. Three different types of shell coating are applied using Si-carbon, Si-carbon black-carbon and Si-carbon black-carbon/graphite nanosheets. It appears that the use of n-Si/carbon black/carbon composite particles in place of n-Si for the shell coating is of great importance to achieve enhanced electrochemical performances from the core-shell composite samples, and additional wrapping with graphite nanosheets leads to a more stable cycle performance of the core-shell composites. [ABSTRACT FROM AUTHOR]

For a given proportion of active material, conductive agent, and binder, performance of the lithium ion battery depends on microstructure of the electrode. Uniform distribution of de-agglomerated particles of carbon black on the active material in the slurry is crucial for establishing a conductive network around the active particles and for improving the adhesion of the electrode to the current collector. Herein, we demonstrate that pre-mixing of carbon black and LiFePO 4 via dry ball-milling achieves the desired microstructure in the electrode coating. Homogeneity of slurry of LiFePO 4 in Poly(vinylidene fluoride)/N-methyl -2-pyrrolidone is demonstrated using measurement of viscosity and dynamic light scattering. Dried electrodes are shown to be uniform via SEM imaging and by a novel "linearly resolved electrical resistivity measurement" technique. Through peel tests it is shown that adhesion of the electrode to the current collector is improved. These improvements reflect in the electrochemical characteristics of the electrode such as increased cycling stability, higher exchange current density and ability of the electrode to perform at a higher C-rate. The electrodes prepared with this method, at an optimal composition, give a higher discharge voltage of ~3 V at 10 C compared to values of 2.4–2.8 V reported for unmodified LiFePO 4 so far. Image 1 • Pre-mixing of carbon black-LiFePO 4 for electrode's desired microstructure. • A novel "linearly resolved electrical resistivity measurement" technique. • The homogeneity of the slurry is measured using rheological properties. • Effective transfer of LFP properties to the electrode performance. [ABSTRACT FROM AUTHOR]