Generation Lithium-ion Batteries Research Articles

Lithium-Ion Dynamic and Storage of Atomically Precise Halogenated Nanographene Assemblies via Bottom-Up Chemical Synthesis.

Graphene has received much scientific attention as an electrode material for lithium-ion batteries because of its extraordinary physical and electrical properties. However, the lack of structural control and restacking issues have hindered its application as carbon-based anode materials for next generation lithium-ion batteries. To improve its performance, several modification approaches such as edge-functionalization and electron-donating/withdrawing substitution have been considered as promising strategies. In addition, group 7A elements have been recognized as critical elements due to their electronegativity and electron-withdrawing character, which are able to further improve the electronic and structural properties of materials. Herein, we elucidated the chemistry of nanographenes with edge-substituted group 7A elements as lithium-ion battery anodes. The halogenated nanographenes were synthesized via bottom-up organic synthesis to ensure the structural control. Our study reveals that the presence of halogens on the edge of nanographenes not only tunes the structural and electronic properties but also impacts the material stability, reactivity, and Li+ storage capability. Further systematic spectroscopic studies indicate that the charge polarization caused by halogen atoms could regulate the Li+ transport, charge transfer energy, and charge storage behavior in nanographenes. Overall, this study provides a new molecular design for nanographene anodes aiming for next-generation lithium-ion batteries.

Fast ionic conductor MnSe supported Micron-Si embedded in three-dimensional N-doped carbon matrix for lithium-ion batteries

Silicon is regarded as the most potential anode for the next generation lithium-ion batteries (LIBs) since its superhigh specific capacity and abundant reserves. Nonetheless, the grievous volume variation and inferior connate conductivity imped its further step on the commercial application. Herein, three-dimensional (3D) porous N-doped carbon microspheres, in which silicon is embedded and supported by MnSe, are fabricated via a simple spray drying method, named as MnSe/Si@NC. Such synergy conduces to the weaker polarization phenomenon and lower reactive barrier. Multi kind of electrochemical tests announce that the 3D network supported by MnSe and synthetical chemical bridge bonds, can remarkably ameliorate electron conductivity and structural stability. Benefit from the reasonably designed materials, the MnSe/Si@NC-10 anode expresses an outstanding cycling stability of 1030.8 mAh·g−1 at 2 A g−1 over 1000 cycles and extremely low-capacity loss rate for each cycle with about 0.27 ‰. In a word, this work can provide reference for the designing and preparation of high-performance anode materials utilized in LIBs.

Recent Progress of High Voltage Spinel LiMn1.5Ni0.5O4 Cathode Material for Lithium-Ion Battery: Surface Modification, Doping, Electrolyte, and Oxygen Deficiency.

High voltage spinel LiMn1.5Ni0.5O4 (LMNO) is a promising energy storage material for the next generation lithium batteries with high energy densities. However, due to the major controversies in synthesis, structure, and interfacial properties of LMNO, its unsatisfactory performance is still a challenge hindering the technology's practical applications. Herein, this paper provides general characteristics of LiMn1.5Ni0.5O4 such as spinel structure, electrochemical properties, and phase transition. In addition, factors such as electrolyte decomposition and morphology of LMNO that influence the electrochemical performances of LMNO are introduced. The strategies that enhance the electrochemical performances including coating, doping, electrolytes, and oxygen deficiency are comprehensively discussed. Through the discussion of the present research status and presentation of our perspectives on future development, we provide the rational design of LMNO in realizing lithium-ion batteries with improved electrochemical performances.

Enhancing the Electrochemical Performances of Disordered Li1.23Ni0.3Nb0.3Fe0.16O0.85F0.15 Cathode Material for Lithium-Ion Batteries by LiNbOx Coating.

For the next generation of lithium-ion batteries (LIBs), it is primary to seek high capacity and long-lifetime electrode materials. Li-excess disordered rock-salt structure (DRS) cathodes have gained much attention due to their high specific capacity. However, Li-excess can lead to a decrease in the structural stability of an electrode material. A new Li-rich DRS oxyfluorides, Li1.23Ni0.3Nb0.3Fe0.16O0.85F0.15 (F0.15) with a series amounts of LiNbOx (LN) coating (0, 5, 10, and 15 wt % denoted as F0.15-LN0, F0.15-LN5, F0.15-LN10, and F0.15-LN15, respectively), are successfully synthesized and evaluated as cathode materials in LIBs. Among them, F0.15-LN10 exhibits the highest initial discharge specific capacity of 296.1 mAh g-1 (at a current density of 20 mA g-1) with the capacity retention rate of 14% higher than that of the uncoated F0.15 after 80 cycles. Even at 300 mA g-1, F0.15-LN10 still delivers the highest discharge specific capacity of 130 mAh g-1. After 20 cycles, the charge-transfer impedance of F0.15-LN10 remained the smallest. The characterizations indicate that LN coating reduces the surface polarization of the cathode materials, slows the interfacial side reactions between the electrolyte and the electrode, and speeds up the Li+ diffusion. These results demonstrate that LN coating is an effective strategy to improve the electrochemical performance.

Exploring solvation structure and transport behavior for rational design of advanced electrolytes for next generation of lithium batteries

The efficacy of electrolytes significantly affects battery performance, leading to the development of several strategies to enhance them. Despite this, the understanding of solvation structure remains inadequate. It is imperative to understand the structure–property–performance relationship of electrolytes using diverse techniques. This review explores the recent advancements in electrolyte design strategies for high capacity, high-voltage, wide-temperature, fast-charging, and safe applications. To begin, the current state-of-the-art electrolyte design directions are comprehensively reviewed. Subsequently, advanced techniques and computational methods used to understand the solvation structure are discussed. Additionally, the importance of high-throughput screening and advanced computation of electrolytes with the help of machine learning is emphasized. Finally, future horizons for studying electrolytes are proposed, aimed at improving battery performance and promoting their application in various fields by enhancing the microscopic understanding of electrolytes.

Synthesis and characterization of core–shell high-nickel cobalt-free layered LiNi0.95Mg0.02Al0.03O2@Li2ZrO3 cathode for high-performance lithium ion batteries

High-nickel cobalt-free layered cathode is regarded as a highly potential cathode material for the next generation lithium ion batteries (LIBs) because of its high energy density, low cost and environmentally benign. However, the poor cycle performance caused by its intrinsic unstable structure and chemo-mechanical instability frustrates its practical applications. Herein, we have developed a new core–shell high-nickel cobalt-free layered LiNi0.95Mg0.02Al0.03O2@Li2ZrO3 (LZO-NMA9523) cathode for high-performance LIBs. The Li2ZrO3 coating layer firstly helps to suppress and reduce the degree of Li+/Ni2+ cation mixing during the material preparation process. In addition, the Li2ZrO3 coating layer can not only accommodate the volume variations and enhance the electricity of the active materials, but also effectively inhibit the harmful irreversible phase transition during the charging/discharging process, thus greatly stabilizing the structure of the high-nickel cobalt-free cathode. As an advanced cathode for LIBs, the LZO-NMA9523 exhibits an excellent reversible capacity of 146.9 mAh g−1 after 100 cycles at 0.5 C with capacity retention of about 80%. This study provides a possible high-nickel cobalt-free layered cathode material for the next generation LIBs.

Ladderlike polysilsesquioxanes derived dual-carbon-buffer-shell structural silicon as stable anode materials for lithium-ion batteries

Silicon-carbon (Si/C) composite materials have been proven to be one of the most promising anode materials for the next generation of lithium-ion batteries (LIBs) due to their high theoretical capacity. However, the substantial volume changes during alloying/dealloying processes have posed significant challenges to the working lifespan of Si-based anodes. In this study, we designed a dual-carbon-layer-structured Si composite anode material (DCS-Si). Using ladderlike polysilsesquioxanes as a precursor, we employed a zinc thermal reaction to internally reduce the Si–O–Si framework to Si0. Simultaneously, the phenyl groups directly connected to Si atoms served as a carbon source for the internally dense coating layer. The obtained product underwent further coating controllable pyrolysis reactions to form an external carbon coating layer. As anode for LIBs, DCS-Si delivered a reversible specific capacity exceeding 1000 mAh g−1. Even after 1350 cycles at a current density of 0.3 A g−1, the specific capacity remained above 500 mAh g−1. Moreover, even under a high current density of 3 A g−1, after nearly 1000 cycles, the capacity retention rate still exceeded 70%. Further testing of the full cell also indicated that DCS-Si is a highly promising high-energy-density anode, with potential applications in future commercial lithium-ion batteries.

Mixed crystal FeFx submicron spheres loaded on fluorinated graphene as cathode materials for Lithium-Ion batteries

Iron fluoride (FeF3 and FeF2) is a potential candidate for the next generation of lithium-ion battery (LIBs) cathode materials due to their high theoretical specific capacity and low cost. However, previous studies have reported that the poor conductivity of FeF3 and FeF2 prevents their theoretical specific capacity from being effectively realized. Herein, fluorinated graphene loaded FeFx (FeFx@FG) submicron sphere was synthesized using graphene oxide and utilized as cathode materials for LIBs. Characterization by X-ray diffraction and transmission electron microscopy confirmed that the synthesized FeFx (x = 2 and 3) contains mixed FeF3 and FeF2crystals. The mixed crystal structure enables the FeFx@FG submicron sphere composite to display two steps in the electrochemical reaction when FeF3 and FeF2 discharge cooperatively, leading to excellent discharge performance. In addition, since the FG prepared by acid thermal method has good conductivity, it can significantly improve the FeFx conductivity and specific capacity when being connected to FG via C-F bond. The electrochemical tests show that the initial discharge capacity of FeFx@FG is as high as 394.24 mAh/g at the rate of 0.2C in the range of 1.5–4.0 V at 25 °C and display an excellent discharge capacity retention rate after the first discharge process, showing great potential of the mixed crystalline iron fluoride cathode in the field of lithium-ion batteries.

Molten-Salt-Assisted Strategy Enables High-Rate Micron-Sized Single-Crystal Li-Rich, Mn-Based Layered Oxide Cathode Materials.

Li-rich Mn-based layered oxides (LMLOs) are expected to be the most promising high-capacity cathodes for the next generation of lithium-ion batteries (LIBs). However, the poor cycling stability and kinetics performance of polycrystalline LMLOs restrict their practical applications due to the anisotropic lattice stress and crack propagation during cycling. Herein, B-doped micron-sized single-crystal Co-free LMLOs were obtained by molten-salt (LiNO3 and H3BO3)-assisted sintering. The results reveal that the low-melting-point molten salt can serve as liquid-phase media to improve the efficiency of atomic mass transfer and crystal nucleation and growth. The modified single-crystal LMLO cathodes can resist the accumulation of anisotropic stress and strain during the cycling and reduce interface side reactions, thus achieving excellent high-voltage stability and kinetics performance. The reversible specific capacity of the single crystals is 210.8 mAh g-1 at 1C with a voltage decay rate of 1.95 mV/cycle and up to 161.1 mAh g-1 at 10C with a capacity retention of 81.06% after 200 cycles.

Chitosan binders for sustainable lithium-sulfur batteries: Synergistic effects of mechanical and polysulfide trapping properties

The lithium-sulfur (Li-S) system is a promising candidate for the next generation of lithium batteries; however, for practical applications, there are still problems to solve as the loss of active material due to polysulfides diffusion and migration (shuttle effect), passivation of interfaces of both electrodes by deposition of insulating species. Chitosan, as an abundant and sustainable biopolymer has been previously modified to solve issues related to polysulfides retention through biopolymer functionalization; however, the effect of such modifications on the mechanical properties, related to the structural modifications, has been poorly investigated; moreover, the coupled effects of both phenomena, polysulfide trapping capacity and mechanical properties, and its impact on battery capacity and cyclability has not been discussed. In order to determine those effects, in this work is proposed a new binder based on chitosan modified by Methanesulfonic Acid as a plasticizer in the fabrication of sulfur cathodes for Li-S batteries. The improvement in the overall performance of the system was investigated by C-Rate, deep cycling and tensile test, and the results were compared with those of the sulfur cathode using brittle and water-insoluble pristine chitosan as binder. Our results indicated that the Chitosan – Methanesulfonic Acid, ChMSA25 polymer network, is able to modulate the mechanical strength and binding performance of the system. Due to the aforementioned characteristics, the ChMSA25 based sulfur cathode exhibits a low-capacity fade (0.058% per cycle) at 1.0 C for 500 cycles. Therefore, the ChMSA25 binder is a promising candidate for the development of high-performance, water processable lithium-sulfur batteries.

Investigation on the heat generation and heat sources of cylindrical NCM811 lithium-ion batteries

High temperature may cause the degradation of capacity and lifespan for the batteries, and even possibly triggers the thermal runaway. Therefore, in order to safe use of batteries, investigation on the heat generation characteristics of lithium-ion batteries is essential to guard the design of thermal management system (TMS). In this work, the heat generation rate (HGR) and heat sources of the 18650 NCM811 battery is investigated by both the isothermal calorimetry test and calculation using the modified Bernardi model, respectively. It is revealed that during charging or discharging, the irreversible heat increases rapidly at low SOC due to large internal resistance, while the reversible entropic heat becomes more important at about 40–60 % SOC due to high entropy coefficient therein. Moreover, the ratio between heat sources has been revealed. The irreversible heat is dominated among the heat sources during charging/discharging with a proportion of 76.33–96.65 %. Wherein, the ohmic heat contributes the most heat generation. Meanwhile, the reversible heat accounts for the smallest proportion of 3.25–23.67 %. It should be noted that current is the main influence factor to the HGR of the lithium-ion battery. With increasing the current, the irreversible HGR, especially ohmic heat, increases much faster than that of reversible heat, resulting in higher ratio. The calculation data are validated to be well consistent with experimental results, giving insights to the investigation of the heat generation of the lithium ion battery.

Multi-strategies interface and structure design of Li- and Mn-rich layered oxide for all-solid-state lithium batteries

Li- and Mn-rich layered oxide (LMRO) cathode materials is highly potential for next generation lithium-ion batteries as its extremely high energy density. However, the oxygen release and the interfacial side reactions against liquid electrolytes cause severe capacity fading and their practical applications are highly impeded. Herein, all-solid-state lithium-ion batteries (ASSLIBs) are demonstrated to be a promising solution towards practical application of LMROs. For the sulfide electrolyte of Li6PS5Cl, a highly compatible interface of LMRO to the electrolyte can be constructed with extra content of Li2MnO3 in LMRO, which prevents significantly side reaction between the LMRO and electrolyte. Moreover, the Li6PS5Cl electrolyte can provide S2-/SO32- redox couple to suppress the oxygen release of LMROs. Combining a further modification in composition with a few amounts of the LiNiO2, the ionic and electronic conductivities of LMRO are evidently improved, where the highly compatible interface is preserved. As results, a superiorly high capacity of 256 mAh g−1 and an energy density of 874 Wh kg−1 at 0.1 C, meanwhile the superior capacity retention as high as 87% for 1000 cycles at 0.5 C are achieved for ASSLIBs. The result is hopefully of great helpful on realizing the practical applications of LMROs in sulfide-based ASSLIBs.

In Situ Transmission Electron Microscopy Observation of Electrochemical Process Between Li–C Nanocomposites and Multilayer Graphene

AbstractPortable power supplies, particularly lithium‐ion batteries (LIBs), will play a key role in achieving sustainable development goals, and electrode active materials for the next generation of LIBs with higher energy density and longer life time is highly demanded. For this, in situ visualization of Li behavior during the charge/discharge process is essential, and transmission electron microscopy (TEM) will be promising for this purpose. Here, a quite simple experimental setup consisting of a newly developed Li–C nanocomposite film sputter‐deposited onto Au nanoprotrusions at room temperature and graphene synthesized on a W probe at 500 °C for the in situ TEM observation of the battery reaction is proposed. The preservation of the metallic Li in the Li–C film that is transferred to TEM without using any transfer vessels under atmospheric conditions is confirmed by high resolution TEM before the in situ electrochemical process in TEM. After the one cycle of the in situ electrochemical process, the intercalation of Li ions into graphene (lithiation) is clearly observed. Thus, it is concluded that the metallic Li stored in the Li–C film works well as the anode active material in the electrochemical process for solid state LIBs, implying the developed in situ experimental system is promising.

Lithium intercalation in two-dimensional penta-NiN2: insights from NiN2/NiN2 homostructure and G/NiN2 heterostructure.

High-energy-density lithium-ion batteries (LIBs) are essential to meet the requirements of emerging technologies for advanced power storage and enhanced device performance. The next generation of LIBs will require high-capacity anode materials that move beyond the lithium intercalation chemistry of conventional graphite electrodes. The use of two-dimensional (2D) bilayer structures offers immediate advantages in the development of LIBs. Herein, motivated by the recently synthesized 2D Cairo pentagon nickel diazenide (NiN2) material, we conduct a scrutiny of the intercalation process of lithium atoms in the interlayer gap of NiN2/NiN2 homostructure. Based on density functional theory (DFT), we demonstrate that the diffusion energy barrier of lithium move across the NiN2/NiN2 anode is relatively low, ranging from 0.058 to 0.52 eV, and the corresponding reversible capacity reaches a remarkable value of 499.0927 mA h g-1 per formula unit, surpassing that of graphite (372 mA h g-1). Furthermore, we investigate a 2D van der Waals (vdW) heterostructure composed of pre-strained structures of graphene and NiN2 for use as an anode material in LIBs. It is found that the introduction of graphene leads to improvements in both electrochemical activity and deformation characteristics. The presented results provide theoretical support for the potential of bilayer structures combining NiN2, suggesting them as promising candidates for the development of high-performance anode materials.

Rational design of SiOx based anode materials for next generation lithium-ion batteries

Lithium-ion batteries (LIBs) have gained significant attention in various fields, as they play a vital role in energy storage and conversion.

Solid-State Electrolyte for Lithium Extraction from Salt Lake Brines

Lithium sources are of great significance for developing the next generation of lithium ion batteries. Most of the world’s lithium sources are found in salt lake brines. The main challenge of lithium extraction from salt lake brine is the separation of lithium ions from other coexisting ions, especially the separation of Li+ and Mg2+. However, the traditional precipitation method for salt lake lithium extraction is cumbersome. In this project, a new electrolytic device with a solid-state electrolyte was developed for high-efficient lithium extraction from salt lake brines. Li1+xAlxTi2−x(PO4)3 (LATP) is a promising NASICON-type solid-state electrolyte, which exhibits high ionic conductivity ( >10-4 S/cm) at room temperature. LATP can be used as a lithium ion conductor, that is only lithium ions can transfer through it, which is ideal for separating lithium ions from other ions in salt lake brines. In this project, high-quality LATP was fabricated at a low cost. An electrolytic device was developed for lithium extraction, in which LATP was used together with a sacrificial anode, molten salts, and an inert cathode. Salt lake brines need to be concentrated by solar and/or wind evaporation before lithium extraction. The electrolytic device was operated above the melting point of the concentrated brine water, at which LATP exhibits a higher ionic conductivity for fast lithium ion transfer. A tiny voltage was applied across the two electrodes to drive the electrochemical reaction. The composition of lithium sources before and after extraction was investigated by inductively coupled plasma-optical emission spectroscopy (ICP-OES). Results show that lithium sources with a higher purity level were successfully extracted with high efficiency. Impurity ions were almost completely blocked by LATP.

Nb-Based Oxides As High Power Negative Electrode Materials

Today, one of the main challenges of lithium-ion batteries is to have the ability to charge faster and to provide high power during longer periods, thus allowing a larger development of intermittent electric power sources [1]. The actual negative electrode materials (graphite and silicon mainly) cannot sustain such high rate capabilities. In this work, we are therefore investigated some materials of the plentiful family of niobium-based oxides. A presentation of old and interesting structures will be briefly reviewed. As an example, the case of KTiNbO5 will be discussed and proposed as efficient negative electrode materials for next generation of lithium ion batteries.The layered KTiNbO5 with a two-dimensional framework represents a playground to produce a large range of closely related phases.[2] The protonated HTiNbO5 analogue is obtained by ion exchange in acidic solution and it preserves a layered structure with a smaller interlayer distance. After dehydration of HTiNbO5 at 400°C, the so-obtained Ti2Nb2O9 phase displays a 2D arrangement with empty channels unlike tunnels of H(K)TiNbO5.In this work, all the synthesized phases were studied as negative electrode materials in lithium-ion batteries. Tested in 1M LiPF6 in EC/DMC between 1.0V and 3.0V vs Li/Li+, these phases have shown different electrochemical behaviors. When HTiNbO5 exhibits a typical plateau during the charge/discharge experiment corresponding to a biphasic phenomenon, lithiation of Ti2Nb2O9 is governed by a solid—solution mechanism. For a better understanding of the charge storage mechanism, we have combined electrochemical experiments with in situ XRD measurements. We have shown that multielectron redox and corner/edge sharing system of Ti/Nb octaedra are at the origin of an interesting capacity of more than 100 mAh.g-1 at a rate of 0.2 A.g-1. A good observed cyclability (< 500 cycles) is in accordance with in situ XRD results showing a reversible behavior of the structure during cycling. Another synthesis method, using Chimie Douce techniques, leads to nanoparticules for both HTiNbO5 and Ti2Nb2O9 and allows an increase of the electrochemical performance of these materials. References : [1] Choi, C. et al, Nature Rev. Mat. 5, 5-19 (2020).[2] A. D. Wadsley, Acta Cryst. 623, 17-41 (1964).

Niobate Anodes for High Rate Lithium-Ion Batteries

Fast charging is one of the key performance requirements for next generation lithium ion batteries, and is directly related to the ease of ionic and electronic transport. However, lithium ion diffusion rates of promising anode materials, such as Li4Ti5O12, anatase TiO2, T-Nb2O5 and Nb18W16O93, are still insufficient. Therefore, nanosizing of the active electrode material is a common strategy to increase the effective lithium ion diffusion transport rate, which unfortunately also decreases the volumetric energy/power density and stability of the battery.Recently, we demonstrated nickel niobate, NiNb2O6, for the first time as a new intrinsic high-rate electrode material,[1] which exhibits an intrinsic high rate performance enabled by its suitable host crystal structure without the requirement of realizing nano-architectures. The NiNb2O6 host crystal structure exhibits only a single type of channel for lithium ion intercalation and can be fully lithiated up to Li3NiNb2O6 with a capacity of about 244 mAh/g at low current densities. Interestingly, a high diffusion coefficient of 10-12 cm2/s at 300 K enables fast (dis)charging at high current densities resulting in high capacities of 140 and 50 mAh/g for respectively 10C and 100C. The minimal volume change during lithiation is the origin of the stable reversible lithiation process in NiNb2O6 and leads to a capacity retention of 81% after 20.000 cycles at 100C. The structural stability and electrochemical behaviour were investigated by various experimental techniques and confirmed by density functional theory (DFT) calculations. Finally, full cell systems against LiFePO4 and NCM811 cathodes demonstrate the promising energy storage performance of nickel niobate anodes in practical battery devices.Our results strongly suggest that niobate-based materials are intrinsic high-rate anode materials without the requirement of realizing nano-architectures as typical for numerous titanium- and niobium-based oxides through complex synthesis procedures to minimize the length scales for lithium diffusion. Recently, we have replaced nickel by other transition metal ions to widen the exploration of niobate compounds for fast lithium ion diffusion. Large variations in electrochemical performance are observed, and the latest results will be presented. This will provide a new perspective on the role of intrinsic high-rate electrode materials for realizing ultrafast anode materials for future energy storage devices.[1] R. Xia et al., Advanced Energy Materials 12 (2022) 2102972.

Cu Foil Modification By Ag Inkjet Printing for Improved Li Plating in Anode-Free Li Batteries

The rush in the development of new generation of lithium-ion batteries (LIB) is focused on enhancing the specific energy of batteries by employing innovative materials and manufacturing techniques. Anode-free lithium metal batteries (AFLBs) are an emerging technology that can almost double the specific energy of LIBs by eliminating the conventional graphite negative electrode or excess lithium metal 1. However, AFLBs are well-known to suffer of fast capacity decay due to the poor lithium plating and stripping efficiency process associated to the typical porous growth of Li during charge 2. Tuning the interfacial electrochemistry was widely demonstrated to be one the most performing key to enable efficient and smooth Li deposition. In this regards, functional coatings of metals as Sn, Al, Zn and Ag have been widely demonstrated to dramatically improve the quality of Li plating process respect to the neat Cu foil substrate, by forming lithium-rich alloys that provide minimum Li nucleation overpotentials 3. Inkjet printing (IJP) could be a viable technique for electrode fabrication in LIBs manufacturing, being a quick, easy and scalable technology able to deposit both thin film and patterned structures 4. However, very poor attention has been paid so far to the potentiality of IJP for Cu modification for improved Li plating in AFLBs.In this work, we employed a Fujifilm Dimatix inkjet printer to achieve “lithiophilic” coatings of Ag nanoparticles deposited on a Cu foil. In particular, potenziodynamic and galvanostatic electrochemical test were employed to investigate the effect of the Ag printed structures on the Li nucleation overpotential. Ex-situ morphological analysis by electron scanning microscopy (SEM) were usefully employed to investigate the surface evolution of the printed electrodes during lithium alloying and plating. In particular, the effect pf patterned Ag structured rather than fully coated Cu was investigated, revealing that patterning can provide more mechanically robust electrode and efficient catalytic sites for Li electrodeposition respect to fully coated inkjet printed electrodes. Bibliography L. Lin et al., Advanced Materials, 34, 2110323 (2022).L. Su and A. Manthiram, Small Structures, 3, 2200114 (2022).X. Gu, J. Dong, and C. Lai, Engineering Reports, 3, e12339 (2021).P. Viviani, E. Gibertini, F. Iervolino, M. Levi, and L. Magagnin, Journal of Manufacturing Processes, 72, 411–418 (2021).

Mixed-Dimensional (1D-2D) Carbon as a Conductive Additive and Enabler for Next Generation Lithium-Ion Batteries

The race to develop the next generation of lithium-ion batteries with higher performance metrics (e.g. energy density, power density, cyclability) has spurred interest in carbon allotropes, such as carbon nanotubes (1D) and graphene (2D). Herein, a new multi-dimensional carbon material, comprised of long and entangled 1D nanotubes that unfurl into a spanning network of 2D sheetlets, is investigated as a conductive additive in lithium-ion battery cathodes. Compared to conventional conductive additives, this so-called 1.5D carbon material improves both electrical and thermal pathways between battery active materials within the electrode.In this presentation, the electrical, thermal, and electrochemical properties of the mixed-dimensional (1.5D) carbon are compared to conventional additives such as carbon black and graphite. Higher active material loadings, less heat generation, and more energy-dense cells can be enabled by the improved electrical conductivity, where three times less carbon black results in one order of magnitude higher electrode conductivity. The thermal conductivity of these cathodes is also enhanced in both the through- and in-plane directions, which is beneficial for battery thermal management. For instance, using a third of the carbon amount results in more than 30% and 240% higher through- and in-plane thermal conductivity values, respectively. The combination of these properties translates to overall improvements in electrochemical performance metrics including rate capability, lower cell impedance, and higher achievable capacities. Compared to cells with conventional carbon black, there is a 20% reduction in ohmic resistance determined by electrochemical impedance spectroscopy. In terms of capacity retention and rate capability, full cells cycled at a 2C charge and 0.5C discharge rate demonstrated 2.5% higher initial capacity than carbon black with a retention of 95% vs 94.4% after 120 cycles.