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The development of elastic nanostructured Si-based anodes holds promise for advancing lithium-ion batteries due to the high theoretical specific capacity exhibited by Si. Combining nanostructured Si with C proves to be a successful strategy in addressing the challenges tied to the substantial volume expansion of Si during lithiation. In this work, a novel Si-based anode is fashioned through a simple and universal strategy, integrating Si nanoparticles with 1D nano-carbonaceous fillers (CPPy-NT) featuring nanotubular morphology and N atoms, and a water-based binder (poly(acrylic acid)). CPPy-NT are derived by carbonizing pre-synthesized polypyrrole nanotubes (PPy-NT). A clear correlation is established among the carbonization temperature for CPPy-NT preparation, N content in CPPy-NT, electrical conductivity, and the electrochemical performance of the ensuing Si/CPPy-NT anode. For comparative analysis, the electrochemical properties of the Si-based anode employing Super P (commercial carbon black) or PPy-NT are contrasted with those of Si/CPPy-NT. Notably, the Si/CPPy-NT anode with CPPy-NT bearing the highest amount of graphitic N sites exhibits a substantial improvement in initial charge capacity (approximately 2200 mAh g−1) and enhanced cycling stability. These findings underscore the potential to elevate the electrochemical activity of the C filler by carefully optimizing morphology, conductivity, and the incorporation of an appropriate amount of graphitic N. [Display omitted] • Synthesis of N-containing 1D nano-carbonaceous fillers with tailored properties. • Integration of N-containing 1D nano-carbonaceous fillers in Si-based anodes. • Development of novel Si/C anodes using an environmentally friendly approach. • Beneficial role of N in enhancing the electrochemical properties of Si/C anodes. [ABSTRACT FROM AUTHOR]

High energy and power density are key requirements for next-generation lithium-ion batteries. One way to improve the former is to reduce the binder and conductive additive content. Carbon black is an important additive that facilitates electronic conduction in lithium-ion batteries and affects the conductive binder domain although it only occupies 5–8% of the electrode mass. However, the function of the structure of carbon black on short- and long-range electronic contacts and pores in the electrode is still not clear and has not been systematically researched in detail. In this work, five carbon blacks with different BET surface areas, oil absorption numbers and ordered graphitic carbon content were investigated. It was found that the ratio of disordered amorphous carbon to ordered graphitic carbon in carbon blacks strongly influences the short- and long-range electrical conduction, and the BET surface area highly affects the pore structure and ionic conductivity in the electrode. Its optimum ratio, indicated by the Raman density I D / I G , is 0.93–0.95. The recommended BET surface area was 130–200 m2/g for this experimental range. The results of this study can provide guidance for the screening of carbon blacks in the lithium-ion battery industry. • Ratio of disordered to ordered carbon highly influences the electronic conduction. • BET surface area highly influences the pore structure and ionic conductivity. • Recommended ratio of carbon is 0.93–0.95 indicated by I D / I G of Raman spectroscopy. • Recommended BET surface area is 130–200 m2/g. [ABSTRACT FROM AUTHOR]

Black phosphorus (BP) has attracted extensive attention in high-rate lithium-ion batteries due to its high theoretical capacity and moderate lithiation potential. However, the large volume expansion and the low conductivity of BP nanostructures in the electrochemical cycle have inhibited the rate performance and long-term cycle stability. In this paper, by combining the glucose-assisted ball-milling and carbonization method, a black-phosphorus/carbon (BP@C) composite anodic material is developed, in which the nano-sized BP nanoparticles are homogeneously embedded in the amorphous carbon matrix. Both the phosphorus-oxygen-carbon bonds and the phosphorus-carbon bonds improve the cross-link between BP and the surface-coated carbon matrix. The unique well-embedded structure promotes the cycling stability and the rate performance of BP@C. The composite shows a high discharge specific capacity of about 1881 mAh g−1 at 0.1 A g−1, the specific capacity at 4 A g−1 is about 63% of the low current capacity, and the discharge specific capacity retains 1130 mAh g−1 after 300 charge-discharge cycles at 0.5 A g−1. Moreover, the significant role of the active unsaturated groups for building the well-embedded composite is further revealed. These results indicate that dual regulation of surface coating and structure optimization offers great potential for further optimizing phosphorus-based anode materials. • Glucose promoted BP homogeneously coated by amorphous carbon matrix. • Carbon matrix improves the conductivity and inhibits the volume expansion. • Different carbon sources influent the cross-linking of BP and the conductive matrix. [ABSTRACT FROM AUTHOR]

Recycling high-valuable metal elements (such as Li, Ni, Co, Al and Cu elements) from scrapped lithium ion batteries can bring significant economic benefits. However, recycling and reusing anode material has not yet attracted wide attention up to now, due to the lower added-value than the above valuable metal materials and the difficulties in regenerating process. In this paper, a novel regeneration process with significant green advance is proposed to regenerate anode material recycled from scrapped Li-ion batteries for the first time. After regenerated, most acetylene black (AB) and all the styrene butadiene rubber (SBR), carboxymethylcellulose sodium (CMC) in recycled anode material are removed, and the surface of anode material is coated with pyrolytic carbon from phenolic resin again. Finally, the regenerated anode material (graphite with coating layer, residual AB and a little CMC pyrolysis product) is obtained. As expected, all the technical indexs of regenerated anode material exceed that of a midrange graphite with the same type, and partial technical indexs are even closed to that of the unused graphite. The results indicate the effective regeneration of anode material recycled from scrapped Li-ion batteries is really achieved. [ABSTRACT FROM AUTHOR]

We report experimental evidence for the specific Li-storage at turbostratic graphene edges of a well-known and cheap Super P ® carbon black (Csp) material, which is usually used as a conductive additive in composite electrodes. Indeed, operando XRD and HR-TEM consistently demonstrate Li insertion occurs with zero expansion of graphene layer up to a composition of Li 0.4 C 6 (150 mA h/g) that is reached at 0.01 V vs. Li + /Li. 7 Li NMR substantiates these results and suggests that the weak electronic transfer from the carbon host to the intercalant could help local reorganization of the layer order as suggested by the unexpected reversible changes of the (002) Bragg peak intensity during the charge-discharge process. Our observations also indicate this insertion mechanism is kinetically favored resulting in remarkable cycling stability over 1000 cycles and power capability allowing to sustain 110 mA h/g at 8 A/g (21 C) in half cell. The capability of Csp as an efficient anode is ultimately demonstrated in a lithium hybrid capacitor against a positive electrode of activated carbon. The full cell delivers a maximum energy of 120 Wh/kg (4.3–2 V) and remarkable capacity retention over 1800 cycles. [ABSTRACT FROM AUTHOR]

All-solid-state lithium-ion batteries (ASSLIBs) are promising candidates for next-generation electric vehicle batteries. The contact interface between the active material (AM) and solid electrolyte (SE) is an important factor that affects the performance of ASSLIB. Composite particles, which are SE-coated AM particles, can form electrodes with large AM-SE contact interfaces. However, they can decrease in cell capacity because of the SE coating layer with electrical non-conductance. This study designed composite particles with conductive additives (CAs) using dry-coating. Acetylene black (AB) and vapor-grown carbon fiber (VGCF) were used as typical CAs, and the composite particles with these CAs were compared with those without CAs and simple mixture. Although the addition of CAs improved the cell capacity and decreased internal resistance, the type of CA significantly affected the rate performance. Because the VGCFs were barely incorporated into the SE coating layer, the incorporation of VGCFs did not improve the rate performance. However, the ABs were effectively incorporated into SE coating layer, resulting in the best rate performance in this study. This difference was due to the ease of supplying electrons to the AM particles. Therefore, AB was suitable for the CA of the composite particles to improve the performance of the ASSLIB. [Display omitted] • Preparation and characterization of composite particles with conductive additives. • VGCF more likely to be placed on the surface of the composite particles. • Acetylene black more likely to be incorporated into the SE coating layer. • Composite particles with acetylene black showed a higher battery performance. • Ease of supplying electrons to the active material affects the rate performance. [ABSTRACT FROM AUTHOR]

Herein, we introduce a multifunctional materials dry coating strategy on LiNi 0.8 Mn 0.1 Co 0.1 O 2 (NMC811) at 1 wt% with a thickness of ca. 100 nm. The materials included high chemical stable Al 2 O 3 (0.33 wt%) to reduce parasitic reactions, high electrical carbon black (0.33 wt%) to reduce internal charge transfer resistance, and high ionic conductive Li 7 La 3 Zr 2 O 12 (0.33 wt%) to enhance Li+ diffusion. The scalable dry coating mechanofusion used can also generate a smooth surface of spherical NMC811 particles enhancing its stability. With an exceptional property of mixed multi-functional materials, the cell of encapsulated NMC811 can perform up to 1000 cycles with 80% capacity retention. Whilst the pristine NMC811 cell can maintain only 39%. The coated NMC811 provides a two-fold specific capacity at a high C-rate (2.0C) compared to the pristine one. Moreover, it also offers excellent safety based on the UN38.3 standard at 18650 cylindrical cells. This multifunctional coating concept may lead to the further development of high-performance Li-ion batteries. [Display omitted] • Reducing intrinsic drawbacks of NMC811with a multifunctional materials coating. • Carbon black-Al 2 O 3 – Li 7 La 3 Zr 2 O 12- NMC811 strong bond at the interface. • Carbon black can reduce internal resistance of NMC811 Li-ion batteries. • Al 2 O 3 can reduce parasitic reactions of NMC811. • Li 7 La 3 Zr 2 O 12 can enhance Li-ion diffusion. [ABSTRACT FROM AUTHOR]

To investigate geometric and electrochemical characteristics of Li ion battery electrode with different packing densities, lithium cobalt oxide (LiCoO 2 ) cathode electrodes were fabricated from a 94:3:3 (wt%) mixture of LiCoO 2 , polymeric binder, and super-P carbon black and calendered to different densities. A synchrotron X-ray nano-computed tomography system with a spatial resolution of 58.2 nm at the Advanced Photon Source of the Argonne National Laboratory was employed to obtain three dimensional morphology data of the electrodes. The morphology data were quantitatively analyzed to characterize their geometric properties, such as porosity, tortuosity, specific surface area, and pore size distribution. The geometric and electrochemical analysis reveal that high packing density electrodes have smaller average pore size and narrower pore size distribution, which improves the electrical contact between carbon-binder matrix and LiCoO 2 particles. The better contact improves the capacity and rate capability by reducing the possibility of electrically isolated LiCoO 2 particles and increasing the electrochemically active area. The results show that increase of packing density results in higher tortuosity, but electrochemically active area is more crucial to cell performance than tortuosity at up to 3.6 g/cm 3 packing density and 4 C rate. [ABSTRACT FROM AUTHOR]

Due to its high theoretical capacity, silicon is a promising active material candidate for the negative electrode of lithium ion batteries. One way to reduce the severe degradation of silicon during charge/discharge cycling, is to use blends of different active materials and a well-balanced ratio of active and inactive materials. To ensure high-energy densities while still maintaining good electronic conductivity and ionic mobility, the necessity of nano-scale conductive carbons within a graphite/silicon composite was evaluated in this study. In particular, the correlation of silicon particle size and the presence of conductive additive was studied in electrodes, predominantly consisting of graphite (15 wt% silicon). Carbon black as conductive additive has a high contact surface area, which can enhance the electronic conductivity within the electrode and thus the rate capability, however, it can also propagate parasitic side reactions. It was determined that composite electrodes containing micron-sized silicon particles depend on the addition of conductive additives with regard to electrochemical performance. Due to high contact area and small transport distances, electrodes based on nano-sized silicon showed comparable capacity retention and a higher specific discharge capacity. Omitting conductive particles from these composite electrodes allowed lower binder amounts, while maintaining a good mechanical electrode integrity. [Display omitted] • Optimization of C/Si-based composite electrode formulation. • Impact of different Si particle sizes varying from nano-to micro-scale. • Evaluation of the necessity of conductive additives in C/Si-based electrodes. • Reduction of inactive material content to maximize energy density. [ABSTRACT FROM AUTHOR]

Electrode processing and performance strongly depend on the active material. Maximizing the active material content of positive composite electrodes enables low cost and high energy density. However, this maximization cannot reach 100%, as composite electrodes additionally consist of binder to provide mechanical integrity and conductive additive to enhance electronic conductivity, which in combination create a flexible porous microstructure for appropriate electron and lithium transport. In this study, the influence of three positive active material classes, layered oxide LiNi 0.6 Mn 0.2 Co 0.2 O 2 , spinel-type LiMn 2 O 4 and olivine-type carbon-coated LiFePO 4 , were investigated regarding the optimum amount of polyvinylidene difluoride as binder and carbon black as conductive additive to achieve high mechanical stability as well as high electronic and ionic conductivity within composite electrodes. Formulation optimization was conducted and compared to a reference electrode formulation with regard to physical, mechanical, electronic and electrochemical properties. In a first step, the binder amount was optimized for each active material class by varying the ratio of binder content to surface area of the solid electrode components. In a second step, the critical conductive additive content was determined. Overall, this strategy allows to decipher material class dependent optimized electrode formulations for high energy density composite electrodes with maximized active material content. [Display omitted] • Strategy to develop material class dependent electrode formulations. • Active material particle surface and size affects binder and conductive additive amount. • Carbon-coated LiFePO 4 based composite electrodes show a high SOH with low conductive additive content. [ABSTRACT FROM AUTHOR]

Many studies have been recently conducted on Ni-rich cathodes to increase cell capacity. The improvement of cell capacity is reaching its limit by increasing Ni content of a cathode material. In addition, increasing Ni content of a cathode material is unsafe due to gas evolution. Thus, research on Ni-rich cathode should proceed in parallel with the development of cell design, i.e., thickening electrode. However, during a calendering process, upper layer particles with low mechanical strength can be fractured, which is a problem with a thick electrode. To solve this issue, electrodes were designed using single crystalline lithium nickel cobalt manganese oxides (NCM) of high mechanical strength together with existing polycrystalline NCM in the present study. Four types of electrodes were tested to determine the best design for the electrode. Among them, double layer of upper layer with single crystalline and lower layer with polycrystalline (DB) completely prevented particle fracturing in the upper layer while maintaining sufficient tortuosity within the electrode. The reaction within the electrode was much more uniform than in other samples. As a result, DB had higher capacity of 34.6 mAh g−1 than the pristine after 40 cycles and a higher capacity of 50.5 mAh g−1 at 2C. • Particles on the upper layer of electrode can be fractured by the pressing force. • The carbon black and PVDF of the upper layer can be agglomerated. • The upper layer of the DB was entirely made of SC, there was no upper layer crack. • The DB enabled a uniform reaction within the electrode without upper layer crack. [ABSTRACT FROM AUTHOR]

Conductive additives, like carbon black or graphite, are essential components of lithium ion batteries due to the limited electrical conductivity of most electrode materials. However, there is still a lack of knowledge about the optimized distribution of these materials within the electrode. A dry mixing process is used in order to prepare a conductive coating by depositing carbon black on the surface of Li(Ni 1/3 Mn 1/3 Co 1/3 )O 2 (NMC) cathode particles. It is demonstrated that this – from a theoretically point of view – favorable distribution does not allow the preparation of working electrodes without taking into account the role of the binder. After adding an organic binder to the slurry, the polymer deposits on top of the carbon shell during drying and inhibits the conductive contact between the particles. This can be avoided by a fraction of distributed carbon particles which are associated with the binder phase providing conductive paths through the isolating organic material. It is shown that carbon black and graphite are principally fulfilling this task, but both materials are leading to varying processing behavior and electrode properties. [ABSTRACT FROM AUTHOR]

To improve the electrochemical performance of Na 2 Li 2 Ti 6 O 14 , carbon black (CB), graphene (GN) and carbon nanotube (CNT) are introduced to fabricate high conductive Na 2 Li 2 Ti 6 O 14 /CB, Na 2 Li 2 Ti 6 O 14 /GN, Na 2 Li 2 Ti 6 O 14 /CNT and Na 2 Li 2 Ti 6 O 14 /CB/GN/CNT by a solid state method. It can be found that only CNT forms a complete three-dimensional conductive network which embeds the randomly distributed Na 2 Li 2 Ti 6 O 14 particles, leading to an improvement of electronic conductivity. The results of cyclic voltammetry, electrochemical impedance spectroscopy and charge–discharge tests reveal that Na 2 Li 2 Ti 6 O 14 /CNT obtains the lowest redox polarization and the highest peak current among all the five samples. As a result, Na 2 Li 2 Ti 6 O 14 /CNT shows the best cycling and rate performances among all the five samples. It reveals a charge capacity of 111.4 mAh g −1 at 100 mA g −1 , 110 mAh g −1 at 200 mA g −1 , 103.9 mAh g −1 at 300 mA g −1 and 98.9 mAh g −1 at 400 mA g −1 . For comparison, bare Na 2 Li 2 Ti 6 O 14 only displays a charge capacity of 89.9 mAh g −1 at 100 mA g −1 , 79.7 mAh g −1 at 200 mA g −1 , 73.7 mAh g −1 at 300 mA g −1 and 69.4 mAh g −1 at 400 mA g −1 . It indicates that the introduction of CNT is more effective to improve the performance of Na 2 Li 2 Ti 6 O 14 than CB, GN and CB/GN/CNT. [ABSTRACT FROM AUTHOR]

The conductive network within a lithium-ion battery electrode is mainly influenced by the process parameters chosen for the dry mixing and wet dispersing step during the production of a coatable electrode slurry, consisting of well-defined components. This conductive network, which results from the electrode's microstructure, plays a major role for the resulting battery cell performance, especially for high performance and power applications. Notable differences can be observed in the subsequently manufactured electrodes due to process-related modifications in the carbon black agglomerate size; mechanical, electrical, and, thus, electrochemical properties are significantly changing with the process parameters set. To allow for a direct correlation of these properties with the electrode structure, a characteristic parameter to describe the carbon black structure in electrode coatings is developed. Based on mercury intrusion measurements, the internal porosity of carbon black particles was determined as a characteristic parameter for the conductive microstructure. For a wide variety of lithium-ion battery cathode samples, the carbon black porosity can be well related to important electrode properties. This underscores the relevance of this carbon black-based microstructure parameter for a knowledge-based process and product optimization. [Display omitted] • Carbon black porosity as a structural parameter for LIB is developed and proven. • Wet dispersion and dry mixing can be used to adjust the carbon black porosity. • Carbon black porosity determines C-rate performance in the form of an optimum curve. [ABSTRACT FROM AUTHOR]

Exploiting fast-kinetics anode materials for lithium-ion batteries shows significant importance for promoting their power density. Herein, we exhibit a rational synthesis strategy of ultrafine spinel Li 4 Ti 5 O 12 nanocrystals and 3D hierarchical architectured composite by an aerosol process in which homogenous suspension of Li 4 Ti 5 O 12 , carbon black, and graphene oxide are atomized and assembled into spherical LTO/CB-G superstructure. The unique 3D architecture is well characterized, and its formation mechanism is discussed in detail. When applied in battery electrode, LTO/CB-G delivers superior rate performance and long cycling durability. Considering the potential large-scale production of graphene and the scalable aerosol-assisted process, 3D Li 4 Ti 5 O 12 -based nanocomposites hold great promise for high-power anodes in real applications of electric transportations. • Ultrafine LTO nanocrystals are synthesized via facile two-phase reaction. • Preparation of graphene-LTO nanocomposites is scalable from spray-drying. • The unique architecture enables superior rate and cycling performance. • The composites hold great promise for practical high-power LIBs anodes. [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]

We report the preparation of thick ceramic electrodes of the olivine LiFePO 4 (LFP) with high mass loading. These electrodes are preparated by means of Powder Extrusion Moulding (PEM), which is a technology easily scalable and cheap. These LFP cathodes are additive-free (neither binder nor extra carbon black) with ~0.5 mm thickness, allowing to develop very high areal capacity (13.7 mA h cm−2). By means of a strict control of sintering process, the carbon coating of the commercial LFP powder remains and the decomposition of the active material is prevented. The optimized self-supported LFP cathode presents good cyclability over 20 cycles at C/10 with no capacity loss. The good electrochemical performance of these novel LFP thick electrodes and their non-flammability make them interesting candidates for both mobile and stationary applications. Image 1 • Thick ceramic electrodes of LiFePO4 with high areal capacities (13.7 mA h cm-2). • Self-supported LFP cathode with good cyclability at C/10. • New generation of high performances and sustainable ultra-thick electrodes. • Thick electrodes (~500 μm) prepared by an easily scalable manufacturing process. [ABSTRACT FROM AUTHOR]

Lithium-alloying materials are of great interest to improve the gravimetric and volumetric energy density of lithium-ion batteries, though their associated volume fluctuation with cycling often leads to poor cycling performance. Active–inactive alloys and blending alloys with carbon materials are common strategies to accommodate volume fluctuation. Herein we set out to optimize graphite–SiO blend electrode formulations to eliminate rapid capacity fade. Electrodes with highly stable cycling were prepared by simple planetary mixing procedures, enabled by the use of just a fraction of a weight percent of commercial SWCNTs as the only conductive additive, and by the appropriate choice of binder/stabilizing agent. In fact, the use of SWCNTs allowed for graphite-free SiO electrodes with approximately 74% higher volumetric energy density relative to traditional graphite electrodes, and superior capacity retention in coin-type full-cell testing versus NMC532 cathodes. • Capacity retention of graphite–SiO blend electrodes is significantly improved by the use of a commercial single-walled carbon nanotube (SWCNT) product relative to carbon black. • Excellent cycling performance is achieved for a variety of blend formulations using only a fraction of a weight percent of SWCNT, and prepared with simple and scalable planetary mixing procedures. • The use of SWCNT conductive additive enables graphite-free SiO electrodes with 74% higher volumetric energy and superior full-cell cycling compared to graphite electrodes. [ABSTRACT FROM AUTHOR]