The quest for high-performance lithium metal batteries has driven an intense scientific focus on understanding the fundamental processes that govern lithium deposition during battery operation. Researchers have long recognized that lithium nucleation—the initial stage where lithium atoms begin to cluster and form solid deposits—is critical to the ultimate morphology, stability, and efficiency of lithium metal electrodes. However, the precise mechanisms dictating lithium nucleation, particularly the roles played by the electrolyte and the substrate interfaces, remain poorly understood. In a groundbreaking study recently published in Nature Chemistry, Hui, Yu, Wang, and colleagues provide compelling insights into how the interplay between the lithium–electrolyte interface and the lithium–substrate interface dictates nucleation behavior, thus opening new avenues toward stable and long-lived lithium metal batteries.
The researchers began by recognizing that the nucleation of lithium does not occur in isolation but rather within a complex interfacial environment. At the core of this environment are two critical interfaces: the interface between lithium and the electrolyte, specifically the solid–electrolyte interphase (SEI), and the interface between lithium and the substrate upon which lithium deposits. The SEI is a chemically heterogeneous, ion-conductive but electron-insulating layer that forms naturally during battery cycling and strongly influences lithium ion transport at the electrode surface. Meanwhile, the substrate provides nucleation sites and pathways for lithium atoms once they arrive at the electrode surface. Understanding how these two interfaces interact and individually or jointly regulate nucleation was the central focus of the team’s investigation.
To dissect these complex interfacial dynamics, the authors employed a physics-based modeling approach that allowed them to quantify the controlling factors in lithium nucleation across a range of electrolyte and substrate combinations. Their model revealed a bifurcation in nucleation regimes primarily governed by the kinetic properties of lithium ion transport and charge transfer at the SEI as well as lithium adatom mobility on the substrate. In scenarios where ion transport through the SEI and charge transfer kinetics were sluggish, the nucleation process was overwhelmingly controlled by the SEI, rendering the substrate properties effectively irrelevant. Conversely, when the SEI allowed rapid lithium transport and charge transfer, the substrate itself became the dominant factor controlling nucleation.
This substrate-controlled nucleation regime was particularly revealing. It highlighted the critical importance of the speed at which lithium adatoms—individual lithium atoms adsorbed onto the substrate surface—move or diffuse along the substrate. The authors showed that for dense, uniform lithium nucleation to occur, the velocity of lithium adatoms must surpass a certain critical threshold that outpaces the formation of unstable nuclei. In other words, a surface that enables fast lithium adatom migration promotes the growth of stable lithium nuclei while suppressing the formation of dendrites and whiskers that can degrade battery performance.
The study elucidates the dualistic nature of lithium nucleation control, emphasizing that improving battery performance is not solely a matter of optimizing the electrolyte or the substrate independently but requires holistic engineering of both interfaces. For instance, simply enhancing SEI transport without considering substrate characteristics will not guarantee uniform and reversible lithium deposition. Similarly, tuning substrate surface energies and adatom mobilities without ensuring compatible electrolyte transport properties may prove insufficient. This dual control mechanism underscores the complexity of electrochemical interface engineering in lithium metal batteries.
Importantly, the findings offer a conceptual framework for rational design of next-generation battery materials. By mapping out regimes where nucleation is governed by SEI characteristics versus substrate properties, the model guides material scientists in choosing or designing electrolytes and substrates that synergistically promote fast lithium transport and substrate diffusion. The authors specifically point toward the need for electrolyte formulations that form SEIs with high lithium ion conductivity and for substrate surfaces engineered at the atomic scale to facilitate rapid lithium adatom migration.
Moreover, the researchers connected nucleation modes to lithium plating and stripping reversibility, a key metric for battery cycle life and safety. Dense, uniform lithium deposition achieved via fast SEI transport and rapid adatom movement minimizes the formation of isolated lithium “dead zones” and mitigates volumetric changes during cycling. These improvements translate to longer cycle life, higher coulombic efficiency, and reduced risk of battery failure modes such as short-circuiting or capacity loss.
To validate their theoretical insights, the team performed simulations that capture the nucleation kinetics under various interface-controlled conditions. Their results reproduced experimental observations reported in the literature where certain electrolyte–substrate combinations favor dendritic growth, while others promote smooth lithium surfaces. This further bolsters the robustness of their model and provides confidence that their framework can be applied in practical battery design scenarios.
The discovery that the lithium nucleation process can be decoupled into SEI-controlled and substrate-controlled regimes represents a paradigm shift in our understanding of metal anode behavior. It moves beyond the simplistic view that dendrite formation is merely a byproduct of electrolyte instability or substrate roughness alone. Instead, it reveals a nuanced balance where interfacial transport kinetics and surface diffusion dynamics jointly dictate the nanoscale pathways of lithium growth.
Looking forward, this research invites the development of advanced characterization techniques that can probe lithium adatom mobility at electrode surfaces in operando conditions. Such experimental validations would further confirm the predictions made by the model and help transitioning the insights into practical battery systems. Additionally, the principles uncovered here may extend beyond lithium metal batteries, offering lessons for other metal anode systems, such as sodium or magnesium, which face similar nucleation challenges.
The critical take-home message from Hui and co-authors’ study is the necessity of fostering simultaneous fast lithium transport through the SEI and fast lithium adatom movement on the substrate to achieve dense, uniform, and reversible lithium metal deposition. Only by mastering these intertwined interfacial dynamics can the long-standing challenges of lithium metal batteries—dendrite growth, low cycle life, and safety concerns—be effectively addressed.
To propel the field forward, future research should also examine how novel substrate materials such as two-dimensional materials, alloys, or nanostructured frameworks influence adatom mobility. Similarly, electrolyte engineering focusing on additive chemistry to tailor SEI properties will be essential. Combining these approaches in light of this new nucleation framework holds promise for breakthroughs toward practical lithium metal batteries.
In conclusion, the study not only deepens fundamental scientific knowledge of lithium nucleation but also provides a practical guide for materials design in battery technology. The interplay of substrate and electrolyte interfaces emerges as a decisive factor controlling lithium metal growth, ultimately shaping the rechargeable battery landscape. By embracing this complex but rich interfacial physics, the path toward safer, more efficient, and longer-lasting lithium metal batteries appears distinctly brighter.
Subject of Research: Lithium nucleation mechanisms and interfacial control in lithium metal batteries.
Article Title: Nucleation processes at interfaces with both substrate and electrolyte control lithium growth.
Article References:
Hui, Z., Yu, S., Wang, S. et al. Nucleation processes at interfaces with both substrate and electrolyte control lithium growth. Nat. Chem. (2025). https://doi.org/10.1038/s41557-025-01911-y
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