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The increasing relevance of automotive lithium‐ion battery cells spotlights the importance of economic production in a high quantity. In this context, production technology for large battery formats is of great relevance. Therefore, it is necessary to identify effects on important cell properties, and based on this, develop an understanding of the interaction between process parameters and product properties. Large‐format cells are not comprehensively examined, particularly, in a large sample size, analyzing cell properties in terms of distributed values. Hence, there is so far no statistical data concerning large‐format batteries and their distributed discharge capacity and self‐discharge. For this reason, and in contrast to other studies, the scope of this work is to investigate a large sample size of 79 industrial‐scale 9 Ah battery cells to ensure statistical relevance and generate distributed data of cell properties. For this purpose, a large number of cells are produced and extensively electrochemically investigated. Subsequently, the essential parameters are correlated with the electrode parameter of carbon black particle size. Hence, the foundation for this process–product–property relationship is laid. [ABSTRACT FROM AUTHOR]

Tin (Sn) is a useful anode material for lithium ion batteries (LIBs) because of its high theoretical capacity. We fabricated oil-in-water emulsion-templated tin nanoparticle/carbon black (SnNP/CB) anodes with octane, hexadecane, 1-chlorohexadecane, and 1-bromohexadecane as the oil phases. Emulsion creaming, the oil vapor pressure, and the emulsion droplet size distribution all affect drying and thus the morphology of the dried emulsion. This morphology has a direct impact on the electrochemical performance of the anode. SnNP/CB anodes prepared with hexadecane showed very few cracks and had the highest capacities and capacity retention. The combination of low vapor pressure, creaming, which forced the emulsion droplets into a close-packed arrangement on the surface of the continuous water phase, and the small droplets allowed for gentle evaporation of the liquids during drying. This led to lower differential stresses on the sample and reduced cracking. For octane, the vapor pressure was high, the droplet sizes were large for 1-cholorohexadecane, and there was no creaming for 1-bromohexadecane. All of these factors contributed to cracking of the anode surface during drying and reduced the electrochemical performance. Choosing an oil with balanced properties is important for obtaining the best cell performance for emulsion-templated anodes for LIBs. [ABSTRACT FROM AUTHOR]

Conducting carbon is added to electrodes of lithium ion batteries (LIBs) to provide electrical conductivity. Because this carbon does not contribute to capacity, there is a drive towards decreasing its content with a goal of lowering the mass of the electrode. Reduced graphene oxide (RGO) has a high electrical conductivity, and is a potential alternative to traditionally used conductive carbon black (CB) in anodes for LIBs. Because of its high aspect ratio, RGO is expected to form a conducting network at lower volume loadings than CB. We report the use of this concept to significantly reduce carbon loading in silicon-carbon anodes for LIBs formed by emulsion-templating. Anodes with 1 wt% RGO and 14 wt% CB (15 wt% total carbon) showed specific capacities and capacity retentions that were comparable to anodes with 30 wt% CB with or without RGO. The capacity retention was significantly lower for anodes with 15 wt% total carbon that had no RGO. Cryo-SEM and SEM images, and electrochemical impedance spectroscopy, confirmed the formation of a conducting carbon network at 15 wt% total carbon loading when 1 wt% of the CB was replaced with RGO, and the lack of a well-connected network without the RGO. [ABSTRACT FROM AUTHOR]

Abstract: We demonstrate a simple method for enhancing the electrochemical performance of air electrodes of Li–air batteries using a polydopamine coating on the surface of carbon. A thin polydopamine layer on Ketjen black carbon clearly modified the surface properties of the air electrode, in turn resulting in improved electrolyte filling. The coating also passivates surface carbon defects, which may be helpful in suppressing parasitic reactions during cycling. Electrochemical tests of the electrode indicate that the introduction of the polydopamine layer is beneficial in that it increases the capacity, lowers the overpotential, and improves the cyclic performance of Li–air cells. These effects may be associated with the increased active catalytic area of the electrode, mostly resulting from the improved wetting characteristics. The suppression of parasitic reactions due to the passivation of carbon defects also contributes to the enhanced cyclic performance of the polydopamine-treated electrode. [Copyright &y& Elsevier]

Abstract: Carbon electrodes with perovskite-type oxide catalysts were investigated as air electrodes for aqueous lithium-air secondary batteries. The system consisted of a water-stable lithium electrode, an aqueous solution of saturated LiOH with 10 M LiCl as electrolyte, and a carbon black air electrode with perovskite catalyst additive. The stability, oxygen reduction and oxygen evolution catalytic activity of the La0.6Ca0.4Co0.8Fe0.2O3, La0.8Sr0.2Fe0.8Mn0.2O3, and La0.6Sr0.4Co0.2Fe0.8O3 perovskite-type oxides were examined in the LiOH–LiCl electrolyte. The perovskite-type oxides were stable in this solution and the oxygen reduction and evolution overpotential on the carbon black substrate was decreased by addition of these perovskite-type oxides. No chlorine evolution was observed during the oxidation reaction on carbon black with the perovskite-type oxides in the LiOH–LiCl electrolyte. The results indicate that carbon black with perovskite-type oxide additives is a potential candidate for the air electrode in the aqueous electrolyte lithium-air rechargeable batteries. [Copyright &y& Elsevier]

Abstract: A new approach to investigate upon the electrochemical properties of Super P carbon black anode material is attempted and compared with conventional mesophase pitch-based carbon fibers (MPCFs) anode material for lithium-ion batteries. The prepared Super P carbon black electrodes are characterized using transmission electron microscope (TEM). The assembled 2032-type coin cells are electrochemically characterized by ac impedance spectroscopic and cyclic voltammetric methods. The electrochemical performance of charge and discharge was analyzed using a battery cycler at 0.1C rate and cut-off potentials of 1.20 and 0.01V vs. Li/Li+. The electrochemical test illustrates that the discharge capacity corresponding to Li intercalation into the Super P carbon black electrode is higher and coulombic efficiency is maintained approximately 84% at the end of the 20th cycling at room temperature. [Copyright &y& Elsevier]

Lots of lithium ion battery (LIB) products contain lithium metal oxide LiNi 5 Co 2 Mn 3 O 2 (LNCM) as positive electrode active material. To increase the conductivity, conductive carbon-based materials including acetylene black and carbon black become necessarily consisted in electrodes. Recently, carbon nano-tube (CNT) appears as a popular choice for conductive carbon in LIB. However, a large quantity of the conductive carbon which cannot provide capacity as the active material will decrease the energy density of batteries. The ultra-high cost of CNT comparing to conventional carbon black is also a problem. In this work, we are going to introduce 'short length' and 'long length' carbon nano-tube (S-CNT and L-CNT) into electrode in order to design a reduced-amount conductive carbon electrode. The whole experiment will be done in 1 Ah commercial type pouch LIB. By decreasing conductive carbon as well as increasing the active material in positive electrode, the energy density of LNCM-based 1Ah pouch type LIBs with only 0.16% of L-CNT inside LNCM positive electrode could reach 224 Wh/kg and 549 Wh/L, in weight and volume energy density, respectively. Also, this high energy density LIB with L-CNT reveals stable cyclability may become a valuable progress in portable devices and electric vehicle (EV) applications. [ABSTRACT FROM AUTHOR]

Lots of lithium ion battery (LIB) products contain lithium metal oxide LiNi5Co2Mn3O2 (LNCM) as the positive electrode's active material. The stable surface of this oxide results in high resistivity in the battery. For this reason, conductive carbon-based materials, including acetylene black and carbon black, become necessary components in electrodes. Recently, carbon nano-tube (CNT) has appeared as a popular choice for the conductive carbon in LIB. However, a large quantity of the conductive carbon, which cannot provide capacity as the active material, will decrease the energy density of batteries. The ultra-high cost of CNT, compared to conventional carbon black, is also a problem. In this work, we are going to introduce long-length carbon nano-tube s(L-CNT) into electrodes in order to design a reduced-amount conductive carbon electrode. The whole experiment will be done in a 1Ah commercial type pouch LIB. By decreasing conductive carbon as well as increasing the active material in the positive electrode, the energy density of the LNCM-based 1Ah pouch type LIB, with only 0.16% of L-CNT inside the LNCM positive electrode, could reach 224 Wh/kg and 549 Wh/L, in weight and volume energy density, respectively. Further, this high energy density LIB with L-CNT offers stable cyclability, which may constitute valuable progress in portable devices and electric vehicle (EV) applications. [ABSTRACT FROM AUTHOR]

Low-molecular-weight carbonyl-containing compounds are considered beneficial energy storage materials in alkali metal-ion/alkaline earth metal-ion secondary batteries owing to the ease of their synthesis, low cost, rapid kinetics, and high theoretical energy density. This study aims to prepare a novel carbonyl compound containing a maleamic acid (MA) backbone as a material with carbon black to a new MA anode electrode for a lithium-ion battery. MA was subjected to attenuated total reflection-Fourier-transform infrared spectroscopy, and its morphology was assessed through scanning electron microscopy, followed by differential scanning calorimetry to determine its thermal stability. Thereafter, the electrochemical properties of MA were investigated in coin cells (2032-type) containing Li metal as a reference electrode. The MA anode electrode delivered a high reversible capacity of about 685 mAh g−1 in the first cycle and a higher rate capability than that of the pristine carbon black electrode. Energy bandgap analysis, electrochemical impedance, and X-ray photoelectron spectroscopy revealed that MA significantly reduces cell impedance by reforming its chemical structure into new nitrogen-based highly ionic diffusion compounds. This combination of a new MA anode electrode with MA and carbon black can increase the performance of the lithium-ion battery, and MA majorly outweighs transitional carbon black. [ABSTRACT FROM AUTHOR]

Solid-electrolyte interface (SEI) between the active material and the electrolyte is critically important to the electrochemical performance of a lithium-ion battery. In this work, a depth profile measurement of the SEI layer after prolonged electrochemical cycling is reported in order to quantify the influence of conducting additives in the development of this layer in mesocarbon microbeads (MCMB) electrodes. It is shown that the SEI in the electrodes having multiwalled carbon nanotubes (CNT) as conductive additive is primarily a multi-layered structure consisting of an outer organic layer near the electrolyte/SEI interface and an inner inorganic layer near the SEI/electrode interface. The chemical analysis of such electrodes exhibits that the inorganic layer is made up of compounds such as Li 2 O, LiF and Li 2 CO 3, while the outer layer consists mainly of organic carbonates, oligomers, traces of randomly distributed Li x PO y F z and undissociated LiPF 6. The chemical analysis of electrodes with carbon black (CB) as conducting additive reveals a similar composition of the outer layer, whereas the inner layer shows a relatively uniform molar amount of organic and inorganic carbonates and species like Li x PO y F z and Li x PO y , resulting in a porous SEI layer which as confirmed in AFM and SEM characterizations. On the other hand, the electrodes containing hybrid (CB-CNT) conducting additives show a relatively higher oligomer content than the electrodes with CNT only. The SEI formed on electrodes with CB-CNT as additives is shown to offer increased flexibility to accommodate partial strain generated due to volume change with narrow cracks exhibited in the SEM micrographs. Further, the variation in surface features and roughness augment the XPS findings. [ABSTRACT FROM AUTHOR]