Formation Of Solid Electrolyte Interphase Film Research Articles

Low-Surface-Area Nitrogen-Doped Carbon Submicrospheres as High-Coulombic-Efficiency and High-Capacity Anodes for Practical Sodium-Ion Batteries.

Nitrogen-doped carbon submicrospheres (NCSMs) are synthesized via an efficient and environmentally friendly one-pot polymerization reaction at room temperature, in which dopamine hydrochloride serves as the source for both carbon and nitrogen. Through leverage of its distinctive structure characterized by minimal surface area, fewer oxygen-containing functional groups, and a heightened presence of active nitrogen-doping sites, the synthesized NCSM showcases a noteworthy initial Coulombic efficiency (ICE) of 84.8%, a remarkable sodium storage capacity of 384 mAh g-1, an impressive rate capability of 215 mAh g-1 at 10 A g-1, and a superior cyclic performance, maintaining 83.0% of its capacity after 2000 cycles. The submicron spherical structure, with its limited surface area and scarce oxygen-containing moieties, effectively curtails the irreversible sodium-ion loss in solid-electrolyte interphase film formation, resulting in heightened ICE. The abundant nitrogen doping can expand carbon-layer spacing as well as improve the electron/ion-transport dynamics, guaranteeing a high sodium storage capacity and a strong rate capability. Crucially, the synthesis method presented here is straightforward, effective, and amenable to scaling, offering a novel avenue for the commercialization of sodium-ion batteries.

Perception of insight in the formation of solid electrolyte interphase

While the solid electrolyte interphase (SEI) film in carbonate-based lithium-ion batteries (LIBs) has been extensively studied, less is known about the formation of SEI due to the complexity and instability of interfacial chemical reactions between Li+ and solvent. This study presents new insights into the formation mechanism of SEI film on graphite anode in ethylene carbonate (EC) and dimethyl carbonate (DMC) co-solvent-based electrolytes. The potential-resolved in-situ electrochemical impedance spectroscopy technology and density functional theory calculations combined with multi-sweep cyclic voltammetry are utilized to confirm that EC prefers to solvate with Li+. Then, a large amount of Li+-EC and a small amount of Li+-DMC solvent molecules undergo solvent migration process and de-solvation at the electrode/electrolyte interface. It was found that Li+-DMC is preferentially de-solvation and reduced to form an unstable SEI film, while Li+-EC inhibits the reduction of DMC and turns the reduction process to be diffusion-controlled. This work provides a fresh perspective on the formation of SEI film by Li+-solvent interaction, which could guide the construction of a stable interface by regulating the Li+-solvation kinetic for high-performance LIBs.

Ultrathin CuF2 -Rich Solid-Electrolyte Interphase Induced by Cation-Tailored Double Electrical Layer toward Durable Sodium Storage.

Solid-electrolyte interphase (SEI) seriously affects battery's cycling life, especially for high-capacity anode due to excessive electrolyte decomposition from particle fracture. Herein, we report an ultrathin SEI (3-4 nm) induced by Cu+ -tailored double electrical layer (EDL) to suppress electrolyte consumption and enhance cycling stability of CuS anode in sodium-ion batteries. Unique EDL with SO3 CF3 -Cu complex absorbing on CuS in NaSO3 CF3 /diglyme electrolyte is demonstrated by in situ surface-enhanced Raman, Cyro-TEM and theoretical calculation, in which SO3 CF3 -Cu could be reduced to CuF2 -rich SEI. Dispersed CuF2 and F-containing compound can provide good interfacial contact for formation of ultrathin and stable SEI film to minimize electrolyte consumption and reduce activation energy of Na+ transport. As a result, the modified CuS delivers high capacity of 402.8 mAh g-1 after 7000 cycles without capacity decay. The insights of SEI construction pave a way for high-stability electrode.

Fe3+-Derived Boosted Charge Transfer in an FeSi4P4 Anode for Ultradurable Li-Ion Batteries.

Ion and electron transportation determine the electrochemical performance of anodes in metal-ion batteries. This study demonstrates the advantage of charge transfer over mass transport in ensuring ultrastable electrochemical performance. Additionally, charge transfer governs the quality, composition, and morphology of a solid-electrolyte interphase (SEI) film. We develop FeSi4P4-carbon nanotube (FSPC) and reduced-FeSi4P4-carbon nanotube (R-FSPC) heterostructures. The FSPC contains abundant Fe3+ cations and negligible pore contents, whereas R-FSPC predominantly comprises Fe2+ and an abundance of nanopores and vacancies. The copious amount of Fe3+ ions in FSPC significantly improves charge transfer during Li-ion battery tests and leads to the formation of a thin monotonic SEI film. This prevents the formation of detrimental LiP and crystalline-Li3.75Si phases and the aggregation of discharging/recharging products and guarantees the reformation of FeSi4P4 nanocrystals during delithiation. Thus, FSPC delivers a high initial Coulombic efficiency (>90%), exceptional rate capability (616 mAh g-1 at 15 A g-1), and ultrastable symmetric/asymmetric cycling performance (>1000 cycles at ultrahigh current densities). This study deepens our understanding of the effects of electron transport on regulating the structural and electrochemical properties of electrode materials in high-performance batteries.

Operational Reliability Modeling and Assessment of Battery Energy Storage Based on Lithium-ion Battery Lifetime Degradation

Battery energy storage (BES) systems can effectively meet the diversified needs of power system dispatching and assist in renewable energy integration. The reliability of energy storage is essential to ensure the operational safety of the power grid. However, BES systems are composed of battery cells. This suggests that BES performance depends not only on the configuration but also on the operating state over different lifetime durations. The lack of safety and reliability is the main bottle-neck preventing widespread applications of BES systems. Therefore, a reliability assessment algorithm and a weak-link analytical method for BES systems are proposed while considering battery lifetime degradation. Firstly, a novel lithium-ion battery model is proposed to identify the degradation rate of solid electrolyte interphase film formation and capacity plummeting. The impacts of different operating conditions are considered in stress factor models. Then, a reliability assessment algorithm for a BES system is introduced based on a universal generating function. An innovative weak-link analytical method based on the reliability importance index is proposed that combines the evaluation results of state-oriented and state-change-oriented indexes through an entropy weight method. The model, algorithm, indexes, and the usefulness are demonstrated in case studies based on aging test data and actual bus operating data. The results demonstrate the effects of the battery status and working conditions on BES reliability. Weak-link analysis is also used to assist BES systems in avoiding short-board batteries to achieve long lifetimes and efficient operation.

Development of advanced electrolytes in Na-ion batteries: application of the Red Moon method for molecular structure design of the SEI layer.

This review aims to overview state-of-the-art progress in the collaborative work between theoretical and experimental scientists to develop advanced electrolytes for Na-ion batteries (NIBs). Recent investigations were summarized on NaPF6 salt and fluoroethylene carbonate (FEC) additives in propylene carbonate (PC)-based electrolyte solution, as one of the best electrolytes to effectively passivate the hard-carbon electrode with higher cycling performance for next-generation NIBs. The FEC additive showed high efficiency to significantly enhance the capacity and cyclability of NIBs, with an optimal performance that is sensitive at low concentration. Computationally, both microscopic effects, positive and negative, were revealed at low and high concentrations of FEC, respectively. In addition to the role of FEC decomposition to form a NaF-rich solid electrolyte interphase (SEI) film, intact FECs play a role in suppressing the dissolution to form a compact and stable SEI film. However, the increase in FEC concentration suppressed the organic dimer formation by reducing the collision frequency between the monomer products during the SEI film formation processes. In addition, this review introduces the Red Moon (RM) methodology, recent computational battery technology, which has shown a high efficiency to bridge the gap between the conventional theoretical results and experimental ones through a number of successful applications in NIBs.

Anions Tuned Solid Electrolyte Interphase in Lithium‐Ion Batteries

AbstractIt is a key and challenging problem to study how the lithium salt anion affects the solid electrolyte interphase (SEI) film formation process. However, the current research focuses on the solvation structure of electrolytes with a general considered conclusion of the preferential reduction effect of anions, while the action mechanism of anions on the solvation structure is rarely studied. Herein, the specific role of anions in the SEI film formation process is illustrated by comparing the influence of anions on the solvation structure with two kinds of boron containing lithium salts. It is found that lithium salt anions can affect the coordination capability of lithium ions and solvents, and then affect the energy consumption in the desolvation process of lithium ions and the composition of SEI film. This work provides a method to study the film formation process, which have certain reference and guide significance for the research of electrolyte field.

Constructing a Stable Si-N-Enriched Interface Boosts Lithium Storage Kinetics in a Silicon-Based Anode.

The stable operation of a SiOx anode largely depends on the intrinsic chemistry of the electrode/electrolyte interface; however, an unstable interface structure and undesirable parasitic reactions with the electrolyte of the SiOx anode often result in the formation of a fragile solid-electrolyte interphase (SEI) and serious capacity decay during the lithiation/delithiation process. Herein, a Si-N-enriched N-doped carbon coating is constructed on the surface of SiOx yolk-shell nanospheres (abbreviated as SiOx@NC) to optimize the SEI film. The two-dimensional covalently bound Si-N interface, on one hand, can suppress the interfacial reactivity of the SiOx anode to enable the formation of a thin SEI film with accelerated diffusion kinetics of ions and, on the other hand, acts as a Li+ conductor during the delithiation process, allowing Li+ to diffuse rapidly in the SiOx matrix, thereby improving the long-term cycling stability and rapid charge/discharge capability of the SiOx anode. A series of characterizations show that the interface charge-transfer barrier and the Li+ diffusion energy barrier through the SEI film are the main factors that determine the interfacial electrochemical behavior and lithium storage performance. This work clarifies the relationship between the SEI characteristics and the interfacial transfer dynamics and aims to offer a more basic basis for the screening of other electrode materials.

Dendrite-free lithium anode achieved under lean-electrolyte condition through the modification of separators with F-functionalized Ti3C2 nanosheets

An unstable solid electrolyte interphase (SEI) and chaotic lithium ion flux are key impediments to commercial high-energy-density lithium batteries because of the uncontrolled growth of rigid lithium dendrites, which would pierce through the conventional polypropylene (PP) separator, causing short circuit and safety issues. Herein, the homogenization of lithium ion flux and the generation of stable SEI layers on lithium anodes were achieved via coating a fluorine-functionalized Ti3C2 (F-Ti3C2) nanosheets on PP separator (F-Ti3C2@PP). F-Ti3C2 nanosheets provide abundant ions pathways to homogeneously manipulate lithium ion flux and increase the Young’s modulus and electrolyte wettability of the separators. In addition, F species derived from the F-Ti3C2 nanosheets would promote the formation of LiF-rich SEI film. The synergistic effect contribute to the uniform lithium deposition. Symmetric Li|Li, asymmetric Li|Cu and full Li|LiFePO4 cells incorporated with the modified separators exhibit improved electrochemical performance even under lean electrolyte conditions. This work provides a feasible strategy to improve the performance of lithium batteries through both fluoridized SEI formation and lithium ion flux manipulation.

MXene Enables Stable Solid‐Electrolyte Interphase for Si@MXene Composite with Enhanced Cycling Stability

AbstractSilicon (Si) has been gaining considerable attention in the field of Li‐ion batteries although unstable solid‐electrolyte interphase (SEI), extreme volume changes and inferior conductivity hinder its practical application. Herein, ultrasonic‐assisted electrostatic self‐assembly of fluidic colloidal coprecipitation of MXene wrapped Si nanoparticles (Si@MXene) is proposed. Utilizing the natural negatively charged MXene to capture positive‐charged Si nanoparticles, the homogeneous Ti3C2Tx MXene coating on Si nanoparticles prevents the nanoparticles from directly contacting the electrolyte and thus enables the formation of a stable SEI film on the composite particulates. Due to the elimination of unstable solid‐electrolyte interphase on the surface of Si nanoparticles, Si@MXene delivers high capacity and excellent retention stability of 94 % after 100 cycles. The strategy demonstrated here offers the rational design of MXene‐coated Si anodes with high capacity and superior cycling stability.

Local Strong Solvation Electrolyte Trade‐Off between Capacity and Cycle Life of Li‐O2 Batteries

AbstractLi‐O2 batteries are promising energy storage devices with ultra‐high theoretical energy density. However, in practice they show severe capacity fading and limited cycle life, meaning that more suitable electrolytes are urgently needed. Here, solvents are combined with high donor number and low donor number, and a Li salt to produce a new local strong solvation effect electrolyte. High discharge capacity and good cycling performance are achieved when the optimized electrolyte is used in a Li‐O2 battery. The optimized electrolyte inhibits side reactions within the battery and facilitates stable solid electrolyte interphase film formation on the surfaces of Li anode. This work opens a new route for the design of high‐performance electrolytes to increase both capacity and cycle life of Li‐O2 batteries.

Anionic Effect on Enhancing the Stability of a Solid Electrolyte Interphase Film for Lithium Deposition on Graphite.

Graphitic carbons and their lithium composites have been utilized as lithium deposition substrates to address issues such as the huge volume variation and dendritic growth of lithium. However, new problems have appeared, including the severe exfoliation of the graphite particles and the instability of the solid electrolyte interphase (SEI) film when metallic lithium is plated on the graphite. Herein, we enhance the stability of the SEI film on the graphite substrate for lithium deposition in an electrolyte of lithium bis(fluorosulfonyl)imide (LiFSI) dissolved in the carbonate solvent, thereby improving the lithium plating/stripping cycle on it. The FSI- anion was found to be responsible for the formation of a compact SEI film under the lithium plating potential and could protect the graphite substrate. These findings refresh the understanding of the SEI stability and provide a suggestion on the design and development of electrolytes for the lithium batteries.

Enhanced reversibility and cyclic stability of biomass-derived silicon/carbon anode material for lithium-ion battery

Silicon as an anode material for lithium ion batteries (LIBs) has drawn wide attention due to exhibiting ten times theoretical capacity than graphite. However, the large reversible capacity loss resulting from the continuous formation of solid-electrolyte interphase (SEI) film and the collapse of the electrode structure hinders the application. Herein, rice husk-derived nano silicon was coupled with N-doped carbon originated from pyrrole. The obtained nano Si/C material demonstrates superior cycling stability but still a relatively low initial coulombic efficiency of 72.0%, which can be boosted to 95.1% by prelithiating with stabilized lithium metal powder (SLMP). The prelithiated Si/C electrode can maintain the structural integrity during Li intercalation/deintercalation process owing to the synergistic effect of N-doped carbon coating layer and excellent electrode interface ascribed to the formation of stable SEI film in the prelithiation stage, contributing to a reversible capacity of up to 1247.8 mAh g−1 with 92.4% capacity retention over 50 cycles. The strategy has a great potential in the area of sustainable chemistry and energy storage system.

Front Cover: Charge‐Transfer Kinetics of The Solid‐Electrolyte Interphase on Li4Ti5O12 Thin‐Film Electrodes (ChemSusChem 16/2020)

The Front Cover shows that to unlock higher-energy-density Li4Ti5O12 (LTO)-based lithium-ion batteries (LIBs), we need to understand the electrochemical characteristics of LTO at low potentials and the properties of the solid–electrolyte interphase (SEI) on LTO. The electrolyte selection influences the SEI film formation, which in turn influences the de-solvation process. Findings in this study rationalize a greater need for designing the interfacial chemistry for safer, fast-charging, and higher-energy-density LTO-based LIBs. More information can be found in the Full Paper by R. N. Nasara et al.

Aluminum electrolysis derivative spent cathodic carbon for dendrite-free Li metal anode

Li metal anode is one of the most promising anodes for next-generation high-energy-density batteries. However, some lethal challenges, such as Li dendrite, inferior coulombic efficiency, and infinite volume change during repeated Li plating/stripping restrict its practical application. Although carbon-based materials are ideal hosts for Li deposition, unsatisfied lithiophilic property and vulnerable solid electrolyte interphase (SEI) film still remain unsolved. Herein, we report the fluorinated mesoporous carbon (FMC) nanosheets derived from spent cathodic carbon of aluminum electrolysis as a versatile dendrite-free current collector. Two types of C–F bonds are discovered in FMC. One is C(sp2)-F, which serves as lithiophilic site for Li nucleation with reduced barrier. The other is C(sp3)-F, which breaks to produce extra LiF during Li deposition, facilitating the formation of stable LiF-rich SEI film. The synergistically designed Li@FMC|LiFePO4 full cells demonstrate improved cycling performance with high coulombic efficiency. This work provides possibility for direct utilization of waste electro-carbon in energy storage application.

Electrochemically Induced Changes in TiO2 and Carbon Films Studied with QCM-D.

Semi-solid fluid electrode-based battery (SSFB) and supercapacitor technologies are seen as very promising candidates for grid energy storage. However, unlike for traditional batteries, their performance can quickly get compromised by the formation of a poorly conducting solid–electrolyte interphase (SEI) on the particle surfaces. In this work we examine SEI film formation in relation to typical electrochemical conditions by combining cyclic voltammetry (CV) with quartz crystal microbalance dissipation monitoring (QCM-D). Sputtered layers of typical SSFB materials like titanium dioxide (TiO2) and carbon, immersed in alkyl carbonate solvents, are cycled to potentials of relevance to both traditional and flow systems. Mass changes due to lithium intercalation and SEI formation are distinguished by measuring the electrochemical current simultaneously with the damped mechanical oscillation. Both the TiO2 and amorphous carbon layers show a significant irreversible mass increase on continued exposure to (even mildly) reducing electrochemical conditions. Studying the small changes within individual charge–discharge cycles, TiO2 shows mass oscillations, indicating a partial reversibility due to lithium intercalation (not found for carbon). Viscoelastic signatures in the megahertz frequency regime confirm the formation and growth of a soft layer, again with oscillations for TiO2 but not for carbon. All these observations are consistent with irreversible SEI formation for both materials and reversible Li intercalation for TiO2. Our results highlight the need for careful choices of the materials chemistry and a sensitive electrochemical screening for fluid electrode systems.

Trifluoropropylene Carbonate‐Driven Interface Regulation Enabling Greatly Enhanced Lithium Storage Durability of Silicon‐Based Anodes

AbstractThe extremely high specific capacity of Si anodes is a double‐edged sword, bringing both high energy density and poor lifespan to Li‐ion batteries (LIBs). Despite recent advances in constructing nanostructured/composite‐Si anodes with an alleviated volume change and improved cycle life, daunting challenges still remain for Si anodes to suppress the irreversible capacity loss associated with the repeated rupture/reconstruction of the solid electrolyte interphase (SEI) layer. Herein, an electrolyte‐based optimization strategy is devised to in situ construct a thin, continuous, and mechanically stable SEI film on Si surface by using a trifluoropropylene carbonate (TFPC) cosolvent, targeting highly stable Si‐based anodes for LIBs. TFPC is featured with its low unoccupied molecular orbital energy, high reduction potential and outstanding film‐forming capability, outperforming those of the state‐of‐the‐art fluoroethylene carbonate additive. More importantly, TFPC plays a key role in regulating the structure and component of SEI layer. As such, 10 wt% TFPC addition promotes the formation of an optimal SEI film with appropriate amounts of polyolefins and LiF, endowing the SEI layer with enhanced rigidity and toughness as well as high ionic conductivity. Both the Si nanoparticle‐based and Si/C composite electrodes deliver a greatly enhanced cycling stability, rate capability, and overall structural integrity in such optimized electrolyte.

Thermoplastic Elastomer Coated-Snsb As an Anode Electrode for Li-Ion Batteries

The demand for developing next generation Li-ion batteries (LIBs) with high energy density and long cycle life drives the research toward alternative electrode materials with larger specific capacities. Among the several materials proposed to replace graphite (372 mAh g-1) as an anode material, antimony (Sb) and tin (Sn) have long been considered as an attractive replacement due to their superior lithium storage capacities of 660 mAh g−1 and 994 mAh g−1, respectively 1, 2. Unfortunately, the electrochemical performance of these materials fades during cycling because of the electrical contact loss induced by large volume variations combined with the continuous growth of a solid electrolyte interphase (SEI) layer at the surface hindering the electron transfer. The use of multi-phase active materials, such as SnSb, instead of pure metals (Sn or Sb) has been used to limit the large volume change by reacting with Li+ at different stages during the charge and discharge process 1. Unfortunately, the alloying/dealloying reaction is still accompanied by a volume change which results in the loss of electrical contact with the active material, Sn agglomeration, and the formation of SEI film on the electrode surface leading to poor electrochemical performance 3, 4. In the present work, micron-sized SnSb coated with a thin thermoplastic elastomer (TPE) is investigated as anode electrode for LIBs. The high failure strain of TPE is a very desirable feature for rechargeable LIBs as it improves the lifetime of high specific capacity anode materials that undergo mechanical fractures induced by large volume variations. Accordingly, an elastomer showing high strain property and good adhesion to the surface of the active material has been designed. Highly rubbery PS-b-PHEA was synthesized by the nitroxide meditated polymerization (NMP) method using a specific polystyrene macroinitiator allowing the presence of long hydroxyethyl acrylate blocks. Figure 1a shows the discharge capacity vs cycle number for the non-coated SnSb and the PS-b-PHEA-coated SnSb cycled at C/10 (i.e. 0.0827 A g–1). It is clearly apparent that the PS-b-PHEA-coated SnSb has superior cyclability than the non-coated SnSb with a reversible capacity of 720 mAh g–1 obtained, whereas only 356 mAh g–1 was retained after 50 cycles for the non-coated SnSb electrode. The remarkable stable capacity is attributed to the elastomer polymer film at the surface of SnSb. Indeed, highly stretchable PS-b-PHEA is able to bear the mechanical stress caused by the large volume variations and thus maintains good quality at the electrode/electrolyte interface and the inter-grains electronic percolation pathways during successive charging and discharging of the battery as well as the limiting the continuous growth of the SEI. Moreover, excellent capacity reversibility was achieved when cycled at fast kinetics (Figure 1b) and multiple C-rates (Figure 1c) confirming the strong protection role of the polymer. The advanced chemical and mechanical properties of PS-b-PHEA open up promising perspectives to significantly improve the electrochemical performance of all electrodes that are known to suffer from large volume variations. Figure 1. Discharge capacity versus the cycle number for PS-b-PHEA-coated SnSb and non-coated SnSb at a rate of (a) C/10 over 50 cycles and (b) 1C over 100 cycles, (c) cycling performance of PS-b-PHEA-coated SnSb at multiple C-rates. References M. Wachtler, J. O. Besenhard and M. Winter, J. Power Sources, 2001, 94, 189-193. P. Antitomaso, B. Fraisse, M. Sougrati, F. Morato-Lallemand, S. Biscaglia, D. Aymé-Perrot, P. Girard and L. Monconduit, J. Power Sources, 2016, 325, 346-350. A. T. Tesfaye, Y. D. Yücel, M. K. S. Barr, L. Santinacci, F. Vacandio, F. Dumur, S. Maria, L. Monconduit and T. Djenizian, Electrochimica Acta, 2017, 256, 155-161. L. Ji, M. Gu, Y. Shao, X. Li, M. H. Engelhard, B. W. Arey, W. Wang, Z. Nie, J. Xiao and C. Wang, Adv. Mater. , 2014, 26, 2901-2908. Figure 1

Ultra-thin solid electrolyte interphase evolution and wrinkling processes in molybdenum disulfide-based lithium-ion batteries

Molybdenum disulfide is considered one of the most promising anodes for lithium-ion batteries due to its high specific capacity; however, it suffers from an unstable solid electrolyte interphase. Understanding its structural evolution and reaction mechanism upon charging/discharging is crucial for further improvements in battery performance. Herein, the interfacial processes of solid electrolyte interphase film formation and lithiation/delithiation on ultra-flat monolayer molybdenum disulfide are monitored by in situ atomic force microscopy. The live formation of ultra-thin and dense films can be induced by the use of fluoroethylene carbonate as an additive to effectively protect the anode electrodes. The evolution of the fluoroethylene carbonate-derived solid electrolyte interphase film upon cycling is quantitatively analysed. Furthermore, the formation of wrinkle-structure networks upon lithiation process is distinguished in detailed steps, and accordingly, structure-reactivity correlations are proposed. These quantitative results provide an in-depth understanding of the interfacial mechanism in molybdenum disulfide-based lithium-ion batteries.

Impact of cis- versus trans-Configuration of Butylene Carbonate Electrolyte on Microscopic Solid Electrolyte Interphase Formation Processes in Lithium-Ion Batteries.

The solid electrolyte interphase (SEI) film, which consists of the products of reduction reaction of the electrolyte, has a strong influence on the lifetime and safety of Li-ion batteries. Of particular importance when designing SEI films is its strong dependence on the electrolyte solvent. In this study, we focused on geometric isomers cis- and trans-2,3-butylene carbonates ( c/ t-BC) as model electrolytes. Despite their similar structures and chemical properties, t-BC-based electrolytes have been reported to enable the reversible reaction of graphite anodes [as in ethylene carbonate (EC)], whereas c-BC-based electrolytes cause the exfoliation of graphite [as in propylene carbonate (PC)]. To understand the microscopic origin of the different electrochemical behaviors of t-BC and c-BC, we applied Red Moon simulation to elucidate the microscopic SEI film formation processes. The results revealed that the SEI film formed in c-BC-based electrolytes contains fewer dimerized products, which are primary components of a good SEI film; this lower number of dimerized products can cause reduced film stability. As one of the origins of the decreased dimerization in c-BC, we identified the larger solvation energy of c-BC for the intermediate species and its smaller diffusion constant, which largely diminishes the dimerization. Moreover, the correlation among the Li+ intercalation behavior, nature of the SEI film, and strength of solvation was found to be common for EC/PC and t-BC/ c-BC electrolytes, confirming the importance of solvation of the intermediates in the stability of the SEI film. These results suggest that weakening the solvation of the intermediates is one possible way to stabilize the SEI film for better charge-discharge performance.