Enabling Fast Charging of Lithium‐Ion Batteries With Regioisomeric Nitrile Additives for Interphase Regulation

ABSTRACT

Achieving fast charging across a wide range of operating conditions remains challenging for lithium (Li)‐ion batteries due to unstable electrode–electrolyte interphases (EEIs) and sluggish interfacial kinetics. Here, we introduce a nitrile‐based additive strategy to regulate interphase formation, while maintaining full compatibility with the commercial LP57 electrolyte, thereby avoiding the need for expensive salts or complex electrolyte reformulation. By incorporating only 0.5 wt.% of 3‐(trifluoromethyl) benzonitrile (AD3), the modified electrolyte significantly enhances fast‐charging performance in 1 Ah Graphite (Gr) | LiNi_0.8Mn_0.1Co_0.1O₂ pouch cells, while also improving low‐temperature, high‐temperature, and high‐voltage stabilities. Mechanistic analysis reveals that AD3 fundamentally alters the interphase formation at both electrodes. At the cathode, AD3 suppresses penetration of decomposition products and enables the formation of a thinner, more uniform cathode‐electrolyte interphase. At the anode, its preferential reduction leads to a thin (10 nm), well‐controlled solid‐electrolyte interphase (SEI) and effectively suppresses Li plating, in contrast to a thick (450 nm), Li‐rich layer formed in LP57. The interfacial improvements reduce parasitic reactions and lower interfacial resistance, as confirmed by distribution of relaxation times (DRT) analysis. The work demonstrates that minimal additive engineering can simultaneously stabilize interphases and enable fast charging, offering a cost‐effective, industry‐compatible pathway for next‐generation Li‐ion batteries.

Fast charging and low‐temperature operation of lithium‐ion batteries (LIBs) are achieved by incorporating only 0.5 wt.% of a nitrile‐based additive into the commercial LP57 electrolyte. The additive enhances Li⁺ transport, stabilizes the solid‐electrolyte and cathode‐electrolyte interphases (SEI and CEI), and suppresses lithium plating.

1. Introduction

Fast charging is a key requirement for next‐generation lithium‐ion batteries (LIBs) to accelerate the electrification of transportation and improve the usability of portable electronics [1, 2]. From an industrial perspective, practical fast charging typically refers to charging rates equal to or exceeding 2C rate or achieving substantial state‐of‐charge recovery within minutes, while maintaining long cycle life and safety [3]. However, such aggressive charging conditions impose severe kinetic and interfacial challenges on conventional graphite (Gr)‐based LIBs [4, 5, 6]. Rapid lithium insertion can lead to sluggish Li⁺ transport, unstable electrode‐electrolyte interphases (EEIs), and lithium (Li) plating on Gr, which may further evolve into dendrite growth, capacity fade, and safety concerns [7, 8, 9, 10]. These issues are fundamentally governed by interfacial reactions and ion‐transport processes during battery operation. Therefore, effective fast‐charging systems require stable EEIs, dendrite‐free lithium deposition, and rapid Li⁺ transport (Figure 1a).

FIGURE 1.

(a) Key electrolyte design considerations for fast charging, including interphase chemistry, dendrite suppression, and Li⁺ transport kinetics. (b) Schematic illustration of electrolyte HOMO‐LUMO energy levels relative to anode and cathode. (c) Radar comparison of electrolyte properties for LP57, advanced electrolytes, and LP57 with additive. (d) Molecular structures of nitrile‐based additives with different CF₃ substitution positions: ortho‐CF₃ (AD2), meta‐CF₃ (AD3), and para‐CF₃ (AD4). (e) Electrostatic potential (ESP) maps of AD2‐AD4 molecules. (f) Electrostatic potential span (ΔESP) values of AD2‐AD4 molecules. (g) Calculated HOMO and LUMO energy levels of EC, EMC, and nitrile additives (AD2‐AD4), with corresponding orbital distributions.

Among the various battery components, electrolyte plays a pivotal role in controlling the interfacial processes. Specifically, electrolytes determine the Li⁺ solvation structure and the desolvation behavior at electrode interfaces, while also governing the chemistry and architecture of the solid‐electrolyte interphase (SEI) and cathode‐electrolyte interphase (CEI) [10, 11]. These factors collectively regulate charge‐transfer resistance, interphasial stability, and ion transport kinetics under high‐rate conditions [12, 13, 14]. In addition, the frontier molecular orbital energies of electrolyte components dictate their reductive and oxidative stabilities relative to electrode potentials (Figure 1b), which strongly influences electrolyte decomposition and interphase formation. Consequently, electrolyte engineering has emerged as one of the most effective strategies for enabling fast‐charging LIBs.

Various electrolyte design strategies have been explored to address fast‐charging challenges, including localized high‐concentration electrolytes (LHCEs), superconcentrated electrolytes, and ionic liquid electrolytes [15, 16, 17, 18]. While these approaches can improve interphase stability and suppress lithium plating, they often rely on expensive salts, such as lithium bis(fluorosulfonyl)imide (LiFSI) or lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), as well as specialized solvents that increase cost and complicate large‐scale manufacturing. Such limitations hinder their widespread adoption in practical battery systems. In contrast, modifying widely used commercial electrolytes through small amounts of functional additives offers a more scalable and cost‐effective pathway. As illustrated in Figure 1c, additive engineering can potentially enhance fast‐charging capability, while maintaining the manufacturing compatibility and cost advantages of conventional electrolytes [19, 20]. LP57 (1 M LiPF₆ in ethylene carbonate (EC)/ethyl methyl carbonate (EMC) (3:7 by wt.) with 2 wt.% vinylene carbonate (VC)) remains as one of the most widely used electrolytes in commercial LIB production due to its balanced electrochemical performance and industrial maturity. Therefore, improving the fast‐charging capability of LP57‐based systems through targeted additive design represents an attractive strategy for practical battery applications.

In this work, we investigate a family of structurally similar nitrile‐based additives, which are hereafter referred to as ortho‐CF₃ (AD2), meta‐CF₃ (AD3), and para‐CF₃ (AD4) (Figure 1d). The nitrile group provides strong electron‐withdrawing characteristics, while the CF₃ substituent further modulates the electronic structure of the molecule, potentially influencing its interfacial reactivity and electrochemical stability [21, 22, 23, 24]. By incorporating only a small amount of nitrile additive (0.5 wt.%) into LP57, the modified electrolyte maintains comparable bulk ionic conductivity while effectively regulating the EEI, thereby improving interfacial charge‐transfer kinetics, stabilizing EEIs, and suppressing Li dendrite formation under high‐rate operation. The resulting electrolyte also improves high‐voltage stability and enables better low‐temperature fast‐discharging performance. To elucidate the origin of the enhanced electrochemical performance, we combine electrochemical characterization with advanced interfacial analysis. Long‐term cycling tests and rate capability measurements reveal significantly improved fast‐charging stability, while distribution of relaxation times (DRT) analysis provides insights into the kinetic processes governing interfacial charge transfer. Furthermore, time‐of‐flight secondary ion mass spectrometry (TOF‐SIMS) coupled with focused ion beam (FIB) techniques is employed to probe the spatial distribution and composition of interphase species, revealing how nitrile‐based additives regulate interphase chemistry to enable stable fast‐charging LIBs.

2. Results and Discussion

To understand the molecular electronic characteristics of these additives, electrostatic potential (ESP) maps were first calculated (Figure 1e). All three molecules exhibit pronounced negative potential regions around the nitrile group, indicating strong electron density localization that could facilitate interactions with Li⁺ and influence interfacial reactions. Despite their similar chemical structures, subtle differences in charge distribution are observed among the three regioisomers, reflecting the influence of the CF₃ substituent through its inductive (and associated field) effects. The overall polarity of the molecules was further quantified by evaluating the electrostatic potential span (ΔESP), which reflects the difference between the maximum and minimum ESP values (Figure 1f). AD2 and AD3 exhibit comparable ΔESP values (∼ 2.89 and ∼ 2.80 eV), while AD4 shows a slightly lower value (∼ 2.68 eV), suggesting differences in molecular polarity that may affect their solvation interactions and interfacial behavior in the electrolyte. Frontier molecular orbital analysis was further performed to evaluate the electronic energy levels of the additives relative to common carbonate solvents (Figure 1g). Compared with EC and EMC, all three nitrile additives exhibit significantly lower LUMO energy levels, indicating a stronger thermodynamic tendency for preferential reduction than the carbonate solvents. However, the frontier orbital energies alone are insufficient to fully describe the behavior of these additives. These results suggest that additive behavior cannot be predicted by any single molecular descriptor, highlighting the need to further investigate the interfacial reaction chemistry governing their electrochemical characteristics.

The electrochemical performance of the nitrile additives was first evaluated in Gr | LiNi_0.8Mn_0.1Co_0.1O₂ (NMC811) coin cells with in‐house synthesized phase‐pure NMC811 cathodes having a uniform particle morphology, as confirmed by SEM and XRD (Figures S1 and S2; Table S1). The initial charge‐discharge voltage profiles reveal that the nitrile additives experience reductive decomposition at ∼ 2.4 V, earlier than the EC decomposition at ∼ 2.9 V (Figures 2a and S3). Despite this initial decomposition, the overall voltage profiles remain similar to that of the baseline LP57 electrolyte, suggesting minimal impact on the bulk electrochemical behavior. Long‐term cycling tests at 1C‐1C charge‐discharge rate demonstrate a significantly improved capacity retention with nitrile‐containing electrolytes compared to the baseline LP57 electrolyte (Figure 2b). Among the three candidates, AD3 exhibits the best cycling stability with 76% capacity retention after 1,000 cycles, outperforming AD2 (70%), AD4 (73%), and LP57 (56%). Afterwards, the charge‐rate performance of the best‐performing AD3 electrolyte was evaluated to benchmark against LP57 (Figure 2c). As seen, cells with AD3 maintain higher normalized capacity at high charge rates compared with the LP57 electrolyte up to 3C rate, indicating improved kinetic performance. In addition, high‐voltage full‐cell cycling tests at 4.4 V further highlight the enhanced oxidative stability enabled by the nitrile additive, with AD3 delivering substantially improved capacity retention (83%) relative to the baseline electrolyte (70%) after 300 cycles (Figure 2d). The improved interfacial stability is also reflected in the high‐temperature cycling performance, where the AD3 electrolyte maintains consistently higher capacity than LP57 during cycling at 45°C over 600 cycles (Figure S4).

FIGURE 2.

(a) Initial charge–discharge voltage profiles of Gr | NMC811 coin cells with LP57 and nitrile additives (AD2–AD4) at C/10 rate between 2.5 and 4.25 V. Electrochemical performances of Gr | NMC811 coin cells with LP57 and additive‐containing electrolyte: (b) long‐term cycling performance, (c) rate capability, and (d) high‐voltage cycling stability. Electrochemical performances of 1 Ah‐pouch cells (Gr | NMC811): (e) differential capacity (dQ/dV) profiles during the first cycle, (f) long‐term fast‐charging cycling performance at 2C charge and 1C discharge rate, (g) charge‐discharge voltage profiles at different rates at 0°C, and (h) low‐temperature rate and cycling performances.

To evaluate the practical applicability of the additive, 1 Ah pouch cells (Gr | NMC811) were further investigated, with the first and third cycle voltage profiles shown in Figure S5. The first cycle dQ/dV profiles in Figure 2e validate that the nitrile decomposes earlier (2.5 V) than EC (2.9 V), rendering significant differences in their SEI chemistries (Figure 2e). Under fast‐charging conditions (2C‐1C charge‐discharge rate), the pouch cells with AD3 display improved cycling stability, retaining 88% capacity after 1,000 cycles compared to 80% for LP57 (Figure 2f). Given the same electrolyte skeleton, this superior performance demonstrates that a highly conductive SEI has been formed through the reductive decomposition of AD3. Therefore, the low‐temperature performance at 0°C was also investigated. The voltage profiles at different discharge rates demonstrate that cells with AD3 maintain lower polarization compared to LP57 (Figure 2g). Even at 2C rate, the AD3 pouch cells can still deliver 0.93 Ah capacity and show virtually no capacity fade after 100 cycles (Figure 2h), further demonstrating the superior interphase formation ability of AD3. It is worth noting that the superior electrochemical performance of AD3 cannot be explained solely by its frontier orbital energy. Although AD4 possesses the lowest calculated LUMO energy, it does not exhibit the best cycling stability or fast‐charging capability, indicating that preferential reduction alone is insufficient to predict additive performance. These results suggest that additive performance cannot be rationalized by any single molecular descriptor. To further elucidate the molecular origin of the superior electrochemical performance of AD3, we next investigated the evolution of the electrode–electrolyte interphase with operando DRT analysis together with TOF‐SIMS characterizations.

To further elucidate the kinetic processes, DRT analysis was performed during both charge and discharge (Figure 3). Of note, Li₄Ti₅O₁₂ (LTO) was employed as the counter electrode to minimize the influence of the anode and facilitate comparison of the cathode‐dominated interfacial kinetics [25]. The DRT contour plots reveal three major impedance contributions associated with the interphase resistance (R_film), charge‐transfer resistance (R _ct), and the Warburg diffusion process (Z_w). During both charge and discharge, the LP57 electrolyte exhibits larger features associated with R_film and R _ct, indicating higher overall interfacial resistance and slower charge‐transfer kinetics. In contrast, the additive‐containing electrolyte exhibits reduced R_film‐ and R _ct‐related responses, suggesting improved interphase stability and reduced interfacial impedance. Meanwhile, the baseline electrolyte also exhibits a slightly larger Z_w contribution, suggesting increased diffusion‐related impedance. This behavior may originate from a thicker interphase, which can hinder Li⁺ transport across the electrode/electrolyte interface and increase the effective diffusion resistance. Overall, these results suggest that the nitrile additive promotes more favorable interfacial kinetics and reduced diffusion‐related impedance in the full‐cell configuration.

FIGURE 3.

Contour plots of distribution of relaxation times (DRT) analysis and the associated voltage profiles for (a) LP57 and (b) AD3, at room temperature, employing Li₄Ti₅O₁₂ (LTO) as a stable counter electrode.

To understand how AD3 modifies cathode interphase formation, we first examine the structural and interfacial characteristics of cycled cathodes. As shown in Figure 4a, the LP57‐cycled cathode exhibits pronounced structural degradation, with clear planar gliding observed in the single‐crystal particles. This is consistent with shear‐induced deformation and structural instability of the single‐crystal particle under repeated high‐rate cycling [26]. High‐resolution cross‐sectional (HR‐CS) TOF‐SIMS imaging of individual secondary‐ion fragments within a single particle is shown in Figure 4b. The cathode cycled in LP57 exhibits more severe internal cracking and void formation, accompanied by stronger carbonate‐related C₂HO⁻ signals along these damaged regions. This suggests that electrolyte‐derived organic species preferentially accumulate within cracks and penetrate into the particle interior during cycling [27]. Although the contrast in LiF₂ ⁻ intensity is not obvious in the cross‐sectional maps alone, the distribution of PO₂ ⁻ highlights a key difference: in LP57, PO₂ ⁻ species tend to infiltrate along the cracking pathways rather than forming a continuous, surface‐confined CEI layer. In contrast, the cathode cycled in AD3 shows less pronounced cracking and a more surface‐localized distribution of interphase species.

FIGURE 4.

Multi‐scale characterization of cathode electrolyte interphase (CEI) formed in LP57 and AD3 electrolytes. (a) SEM of cycled cathode retrieved from Ah‐pouch cells. (b) High‐resolution cross‐sectional (HR‐CS) TOF‐SIMS imaging of FIB‐milled secondary cathode particles. (c) Normalized TOF‐SIMS depth profiles of representative fragments. (d) 3D reconstruction of selected species. (e) Integrated yield of representative secondary‐ion fragments. (f) ¹⁹F NMR spectra of cycled electrolytes. (g) 2D LiF₂ ⁻ thickness mapping extracted from 3D depth profiles. (h) Histogram of LiF₂ ⁻ thickness distribution.

To further resolve the chemical composition and depth distribution of the interphase, normalized TOF‐SIMS depth profiles are presented in Figure 4c. Representative secondary‐ion fragments are selected to track distinct CEI architecture. The transition‐metal (TM) fluoride fragments (NiF₃ ⁻, CoF₃ ⁻, MnF₃ ⁻) originate from surface reconstruction and dissolution of the cathode active materials, reflecting interactions between the active material and electrolyte decomposition products [28, 29]. The C₂HO⁻ fragment serves as a proxy for carbonate‐derived organic species, LiF₂ ⁻ represents inorganic fluorinated species, and PO₂ ⁻ tracks phosphate‐containing products formed from LiPF₆ decomposition [30]. Based on these assignments, LP57 exhibits a sustained and relatively high C₂HO⁻ signal, indicating significant accumulation of carbonate species and the formation of an organic‐rich CEI. The TM fluoride fragments also decay more gradually, suggesting more extensive cathode surface degradation [31]. In addition, the depth at which the ⁶²Ni⁻ signal reaches 80% of its total intensity (used here to define CEI thickness) indicates a relatively thick interphase in LP57 (88 nm). In contrast, AD3 shows suppressed C₂HO⁻ intensity, faster decay of TM fluoride fragments, and an earlier rise of the ⁶²Ni⁻ signal, consistent with a thinner CEI (50 nm) and reduced active material degradation. Notably, the PO₂ ⁻ signal in LP57 extends deeper into the sputtering depth, indicating that LiPF₆‐derived decomposition products penetrate into the particle interior, in good agreement with the HR‐CS imaging. In contrast, these species remain more confined near the outer surface in AD3. Similar depth profiles collected at different locations (Figure S6) show consistent trends, further supporting the differences in CEI thickness and spatial distribution.

These depth‐dependent trends are directly visualized in the three‐dimensional (3D) reconstructions in Figure 4d, where brighter contrast corresponds to greater local abundance and/or thicker accumulation of the detected species [32]. In LP57, carbonate‐ and phosphate‐related species exhibit a heterogeneous distribution and extend into subsurface regions, consistent with the cross‐sectional images. The interphase in LP57, therefore, appears as a bulk‐penetrating, nonuniform layer associated with structural damage. In contrast, AD3 leads to a markedly different morphology, where interphase species are largely confined to the outer surface and display improved lateral uniformity. In particular, LiF‐related species form a more continuous and surface‐localized layer, while organic and phosphate species are suppressed both in intensity and penetration depth. To compare the overall abundance of interphase species, representative secondary‐ion fragments are quantified in Figure 4e. Notably, LP57 exhibits higher overall integrated yields of each secondary‐ion fragment of interest than AD3, indicating more extensive electrolyte decomposition and TM dissolution. However, these integrated values alone do not capture the spatial distribution or quality of the interphase, as they cannot distinguish between uniform surface coverage and localized accumulation within cracks or defects. Therefore, further analysis of surface distribution and interphase thickness is required to fully resolve these differences.

Consistent with the TOF‐SIMS results, ¹⁹F NMR spectra of the cycled electrolytes in Figure 4f show a significantly stronger signal corresponding to POF₂OH in LP57, indicating more extensive LiPF₆ decomposition during cycling [33, 34]. This observation supports the depth‐profiling results, where phosphate‐related species (PO₂ ⁻) are more abundant and penetrate deeper in LP57. In contrast, the reduced POF₂OH signal in AD3 suggests suppressed salt decomposition and a more stable electrolyte environment.

To further assess the spatial heterogeneity, we introduced a net squared deviation analysis of the surface species distribution (Figure S7; Tables S2 and S3). The results show that the average surface signals of the two cathodes are comparable, suggesting a similar level of uniformity for the selected CEI species. To more directly evaluate interphase effectiveness, we focus on LiF‐related species, as LiF is widely recognized as a key inorganic component for a robust CEI due to its chemical stability and ability to passivate the cathode surface [35, 36]. A more critical distinction emerges when analyzing local thickness variation, as shown in Figure 4g (2D mapping) and Figure S8 (3D mapping). Although LP57 exhibits higher total amounts of LiF‐related species, the thickness mapping of LiF₂ ⁻ reveals a highly heterogeneous distribution, with substantial spatial variation across the surface. In contrast, AD3 shows a much more uniform thickness distribution, indicating the formation of a more homogeneous interphase layer. This heterogeneity is further quantified in the histogram analysis in Figure 4h. The thickness distribution of the LiF₂ ⁻‐related layer in LP57 is significantly broader, with a larger full width at half maximum (FWHM), indicating greater variation in local interphase thickness [37]. In contrast, AD3 displays a narrower distribution with smaller FWHM, consistent with a more uniform CEI. Notably, despite the higher LiF‐related signal in LP57, the nonuniform distribution suggests that LiF is preferentially accumulated in localized regions rather than forming a continuous protective layer [38, 39]. This behavior implies ongoing exposure of fresh cathode surfaces, which can continuously react with the electrolyte and drive further decomposition. In contrast, the thinner, more uniform LiF distribution in AD3 enables more effective and consistent surface passivation, even at a lower overall LiF content. Therefore, these results indicate that the effectiveness of the CEI is governed not only by its composition but also critically by its spatial uniformity [40].

While AD3 effectively stabilizes the cathode interface, its higher reduction potential also promotes preferential decomposition on the Gr anode, enabling the formation of a protective interphase. As shown in Figure 5a, LP57 leads to a heavily contaminated Gr surface covered with irregular deposits, suggesting severe electrolyte decomposition and Li plating. In contrast, AD3 maintains a much cleaner surface, with Gr particles remaining clearly distinguishable. High‐resolution cross‐sectional TOF‐SIMS mapping shows strong and localized Li⁻ signals in LP57, indicative of “dead” lithium (Li) accumulation (Li plating), while such features are largely suppressed with AD3 (Figures 5b and S9) [27, 41]. In addition, LiF₂ ⁻ and PO₂ ⁻ signals extend deeper into the LP57‐cycled anode, indicating more pronounced electrolyte decomposition and deeper penetration of decomposition products, resulting in a less effective SEI. This is consistent with the accumulation of highly reactive “dead” Li on Gr surface, which promotes parasitic reactions with the electrolyte. By comparison, AD3 preferentially decomposes on Gr surface to form a more robust SEI that suppresses Li plating and limits the formation of decomposition products.

FIGURE 5.

Interphase characterization of Gr anodes cycled in LP57 and AD3. (a) SEM images of cycled Gr anodes retrieved from Ah‐pouch cells. (b) High‐resolution cross‐sectional (HR‐CS) TOF‐SIMS imaging of FIB‐milled cycled anodes in LP57 (top) and AD3 (bottom). (c) Normalized TOF‐SIMS depth profiles of representative fragments. (d) Integrated yields of representative secondary‐ion fragments. (e) 3D reconstruction of selected species. (f) Relative correlations of selected secondary‐ion fragments in anode samples retrieved from cells filled with LP57 (top) and AD3 (bottom). (g) 2D Li⁻ thickness mapping.

Depth profiles further show pronounced Li⁻ enrichment near the surface in LP57, with the signal persisting beyond 200 nm before gradually decaying, accompanied by sustained C₂HO⁻ and PO₂ ⁻ signals, indicating continuous electrolyte decomposition [42]. The SEI thickness is estimated based on the depth at which the C₈ ⁻ signal (representing bulk Gr) reaches 80%, yielding a thickness of 450 nm for LP57 compared to only 10 nm for AD3. The integrated yields of secondary‐ion fragments (Figure 5d) further support the trends observed in the depth profiles. Consistently, 3D reconstructions of LiF₂ ⁻, C₂H₃O⁻, and Li⁻ show more pronounced accumulation in LP57, whereas AD3 exhibits a more uniform and thinner distribution. Interestingly, the surface uniformity evaluated by net squared deviation analysis appears higher for LP57 (Figure 5f; Tables S4 and S5); however, this arises from the presence of a thick Li‐rich layer that homogenizes the signal. In AD3, the lower apparent uniformity reflects its much thinner interphase, which allows underlying features to be resolved. A more representative comparison is obtained from Li⁻ thickness mapping (Figure 5g), where LP57 exhibits a significantly thicker and spatially heterogeneous Li layer, with the difference between the thickest and thinnest regions exceeding 150 nm [37]. In contrast, AD3 exhibits minimal dead Li formation and a much thinner, more uniform Li⁻ distribution within the SEI. Overall, these results demonstrate that AD3 effectively stabilizes the Gr anode by suppressing dead Li accumulation and regulating SEI formation toward a significantly thinner interphase, thereby mitigating continuous electrolyte decomposition, despite the lower apparent uniformity arising from its limited thickness.

3. Conclusion

In summary, we identify a promising family of nitrile‐based additives that regulates interphase formation through the combined effects of preferential reduction, Li⁺ coordination, and interfacial reaction chemistry. Rather than relying on high salt concentrations or complex electrolyte systems, this approach enables effective interphase engineering within a commercial electrolyte framework with only a minimal additive content. More importantly, this work reveals that cathode interphase effectiveness depends not only on chemical composition, but also critically on spatial uniformity. The presence of beneficial species (e.g., LiF) alone is insufficient without uniform coverage. In contrast, for the Gr anode, controlling SEI thickness and minimizing dead Li accumulation are more important, with uniformity playing a less critical role. This dual regulation of interphases suppresses parasitic reactions and enables reliable fast‐charging performance. Collectively, these findings provide molecular‐level insight into the origins of additive performance within this family of nitrile‐based molecules, while demonstrating a practical, cost‐effective strategy for improving fast‐charging LIBs.

Author Contributions

Chen Liu: conceptualization, methodology, data curation, investigation, validation, formal analysis, writing – original draft. Zehao Cui: methodology, investigation, validation, writing – review and editing. Arumugam Manthiram: methodology, supervision, funding acquisition, project administration, writing – review and editing, validation, investigation.

Conflicts of Interest

The authors declare no conflicts of interest.

Supporting information

Supporting File: anie74489‐sup‐0001‐SuppMat.docx.

Data Availability Statement

The data that support the findings of this study are available from the corresponding author upon reasonable request.