RESEARCH

Dacheng Kuai and Perla B. Balbuena, “Inorganic Solid Electrolyte Interphase Engineering Rationales Inspired by Hexafluorophosphate Decomposition Mechanisms,” J. Phys. Chem. C, 127, 1744-1751, (2023).

Solid electrolyte interphase (SEI) engineering is an efficient approach to enhancing the cycling performance of lithium metal batteries. Lithium hexafluorophosphate (LiPF6) is a popular electrolyte salt. Mechanistic insights into its degradation pathways near the lithium metal anode are critical in modifying the battery electrolyte and SEI…  View more

Stefany Angarita-Gomez and Perla B. Balbuena, “Lithium-ion Transport through Complex Interphases in Lithium Metal Batteries,” ACS Appl. Mater. Interfaces,14, 52, 56758-56766, (2022).

Lithium metal is one of the best anode candidates for next-generation batteries. However, there are still many unknowns regarding the structure and properties of the solid electrolyte interphase (SEI) formed due to electron transfer reactions between the Li metal surface and the electrolyte. In addition, because of the difficulties to study…. View more

Saul Perez Beltran and Perla B. Balbuena, “SEI Formation Mechanisms and Li+ Dissolution in Lithium Metal Anodes: Impact of the Electrolyte Composition and the Electrolyte-to-Anode Ratio,” J. Power Sources, 551, 232203, (2022).

The lithium metal battery is one of today’s most promising high-energy-density storage devices. Its full-scale implementation depends on solving operational and safety issues intrinsic to the Li metal high reactivity leading to uncontrolled electrolyte decomposition and uneven Li deposition. In this work, we study the spontaneous formation of the solid electrolyte interphase (SEI) upon contact of Li metal with the electrolyte and … View more

Francisco Ospina-Acevedo, Ningxuan Guo, and Perla B. Balbuena, “Lithium Oxidation and Electrolyte Decomposition at Li-Metal/Liquid Electrolyte Interfaces,” J. Mater. Chem. A, 8, 17036-17055, (2020).

We examine the evolution of events occurring when a Li metal surface is in contact with a 2 M solution of a Li salt in a solvent or mixture of solvents, via classical molecular dynamics simulations with a reactive force field allowing bond breaking and bond forming. The main events include Li oxidation and electrolyte reduction along with expansion of the Li surface layers forming a porous phase… View more

Ethan P. Kamphaus, Stefany Angarita, Xueping Qin, Minhua Shao, Mark Engelhard, Karl T. Mueller, Vijayakumar Murugesan, and Perla  B. Balbuena, “Role of inorganic surface layer on solid electrolyte interphase evolution at Li-metal anodes,” ACS Appl. Mater. Interfaces, 11, 31467-31476, (2019).

Lithium metal is an ideal anode for rechargeable lithium-battery technology. However, the extreme reactivity of Li metal with electrolytes leads to solid electrolyte interphase (SEI) layers that often impede Li+ transport across interfaces. The challenge is to predict the chemical, structural, and topographical heterogeneities of SEI layers arising from a multitude of interfacial constituents. Traditionally, the pathways and products of electrolyte decomposition processes … View more

Yaobin Xu, Hao Jia, Peiyuan Gao, Diego E. Galvez-Aranda, Saul Perez Beltran, Xia Cao, Phung M. L. Le, Jianfang Liu, Mark H Engelhard, Shuang Li, Gang Ren, Jorge M. Seminario, Perla B. Balbuena, Ji-Guang Zhang, Wu Xu, Chongmin Wang, “Direct in-situ measurement of electrical properties of solid electrolyte interphase on lithium metal anode” Nature Energy, 8, 1345–1354 (2023)

The solid–electrolyte interphase (SEI) critically governs the performance of rechargeable batteries. An ideal SEI is expected to be electrically insulative to prevent persistently parasitic reactions between the electrode and the electrolyte and ionically conductive to facilitate Faradaic reactions of the electrode. However, the true nature of the electrical properties of the SEI remains… View more

Stefany Angarita-Gomez and Perla B. Balbuena, “Ion Mobility and Solvation Complexes at Liquid-Solid Interfaces in Dilute, High Concentrated, and Localized High Concentrated Electrolytes,” Mater. Adv., 3, 6352-6363, (2022).

The underlying mechanisms of the solvated lithium cation diffusion and deposition on the Li metal surface occurring at electrochemical interfaces are still not fully understood. In this work, density functional theory and a thermodynamic integration method implemented in constrained-ab initio molecular dynamics are used to calculate the free energy profile for the lithium cation transport pathway in the absence of an external field … View more

Saul Perez-Beltran, Dacheng Kuai, and Perla B. Balbuena. “SEI Formation and Lithium-Ion Electrodeposition Dynamics in Lithium Metal Batteries via First-Principles Kinetic Monte Carlo Modeling” ACS Energy Lett., 9, 5268–5278 (2024)

The stabilization and enhanced performance of lithium metal batteries (LMBs) depend on the formation and evolution of the Solid Electrolyte Interphase (SEI) layer as a critical component for regulating the Li metal electrodeposition processes. This study employs a first-principles kinetic Monte Carlo (kMC) model to simulate the SEI formation and Li⁺ electrodeposition processes on a lithium metal anode… View more

Sha Tan, Dacheng Kuai,, Zhiao Yu, Saul Perez-Beltran, Muhammad Mominur Rahman, Kangxuan Xia, Nan Wang, Yuelang Chen, Xiao-Qing Yang, Jie Xiao, Jun Liu, Yi Cui,  Zhenan Bao, Perla B. Balbuena, Enyuan Hu, “Evolution and Interplay of Lithium Metal Interphase Components Revealed by Experimental and Theoretical Studies,” J. Am. Chem. Soc. 2024, 146, 17, 11711–11718,

Lithium metal batteries (LMB) have high energy densities and are crucial for clean energy solutions. The characterization of the lithium metal interphase is fundamentally and practically important but technically challenging. Taking advantage of synchrotron X-ray, which has the unique capability of analyzing crystalline/amorphous phases quantitatively with statistical significance, we study the composition and dynamics of … View more

Janika Wagner, Dacheng Kuai, Michail Gerasimov, Fridolin Röder, Perla B. Balbuena, Ulrike Krewer, “Knowledge-driven design of Solid-Electrolyte Interphases on lithium metal: Insights from multiscale modelling” Nat. Comm., 14, 1, 6823, (2023).

Due to its high energy density, lithium metal is a promising electrode for future energy storage. However, its practical capacity, cyclability and safety heavily depend on controlling its reactivity in contact with liquid electrolytes, which leads to the formation of a solid electrolyte interphase (SEI). In particular, there is a lack of fundamental mechanistic understanding of how the electrolyte composition impacts the SEI formation and … View more

Michail Gerasimov, Fernando A. Soto, Janika Wagner, Florian Baakes, Ningxuan Guo, Francisco Ospina-Acevedo, Fridolin Röder, Perla B. Balbuena, Ulrike Krewer, “Species Distribution during Solid Electrolyte Interphase Formation on Lithium Using MD/DFT-Parameterized Kinetic Monte Carlo Simulations” J. Phys. Chem. C, 127, 4872=4886, (2023).

Lithium metal batteries are one of the promising technologies for future energy storage. One open challenge is the generation of a stable and well performing Solid Electrolyte Interphase (SEI) between lithium metal and electrolyte. Understanding the complex interaction of reactions at the lithium surface and the resulting SEI is crucial for knowledge-driven improvement of the SEI… View more

Dacheng Kuai and Perla B. Balbuena, “Solvent Degradation and Polymerization in the Li-Metal Battery: Organic Phase Formation in Solid-Electrolyte Interphases,” ACS Applied Materials & Interfaces, 14, 2817-2824, (2022).

The products of solvent polymerization and degradation are crucial components of the Li-metal battery solid-electrolyte interphase. However, in-depth mechanistic studies of these reactions are still scarce. Here, we model the polymerization of common lithium battery electrolyte solvents─ethylene carbonate (EC) and vinylene carbonate (VC)─near the anode surface. Being consistent with the molecular calculation, ab initio molecular dynamic (AIMD) … View more

Saul Perez Beltran, Xia Cao, Ji-Guang Zhang, Patrick Z. El-Khoury, and Perla B. Balbuena, “Influence of Diluent Concentration in Localized High Concentration Electrolytes: Elucidation of Hidden Diluent-Li+ Interactions and Li+ Transport Mechanism,” J. Mater. Chem. A, 9, 17459-17473, (2021).

Localized high concentration electrolytes (LHCE) offer a viable dilution strategy for high concentration electrolytes (HCE) as the dilution process barely impacts the enhanced reductive/oxidative behavior of the HCE formulation but significantly lowers the overall viscosity and, in most cases, increases the ionic conductivity. On the other hand, experimental studies indicate that fluorinated ether electrolytes such as … View more

Yu Zheng and Perla B. Balbuena, “Localized High Concentration Electrolytes Decomposition under Electron-rich Environments“, J. Chem. Phys, 154, 104702 (2021).

Localized high concentration electrolytes have been proposed as an effective route to construct stable solid-electrolyte interphase (SEI) layers near Li-metal anodes. However, there is still a limited understanding of the decomposition mechanisms of electrolyte components during SEI formation. In this work, we investigate reactivities of lithium bis(fluorosulfonyl)imide (LiFSI, salt), 1,2-dimethoxyethane (DME, solvent), and … View more

Saul Perez Beltran, Xia Cao, Ji-Guang Zhang, and Perla B. Balbuena, “Localized High Concentration Electrolytes for High Voltage Lithium-Metal Batteries: Correlation between the Electrolyte Composition and its Reductive/Oxidative Stability,” Chem. Mater. 32, 5973-5984, (2020).

We demonstrate a first-principles screening methodology as an effective tool to explore electrolyte formulations for the new generation of high energy density rechargeable batteries. We study the liquid structure and electronic properties in dilute electrolytes, high concentration electrolytes (HCE), and localized high concentration electrolytes (LHCE), with focus on electrolyte formulations based on lithium bis(fluorosulfonyl)imide (LiFSI)… View more 

Yu Zheng, Fernando A. Soto, Victor Ponce, Jorge M. Seminario, Xia Cao, Ji-Guang Zhang, and Perla B. Balbuena, “Localized High Concentration Electrolyte Behavior near a Lithium-Metal Anode Surface,” J. Mater. Chem. A, 7, 25047-27055, (2019).

Wide-scale practical application of rechargeable lithium–metal batteries remains a significant challenge due to dendrite growth. To overcome this challenge, electrolytes must be designed to allow for the formation of protective solid electrolyte interphase (SEI) layers on the highly reactive lithium–metal anode (LMA) surfaces. Recently, novel localized high-concentration electrolytes (LHCEs) were introduced as a potential solution to enable dendrite-free cycling of … View more

Stefany Angarita-Gomez and Perla B. Balbuena, “Solvation vs. Surface Charge Transfer: An Interfacial Chemistry Game Drives Cation Motion,” Chem. Comm., 57, 6189-6192, (2021)

Electrolyte structure and ion solvation dynamics determine ionic conductivities, and ion (de)solvation processes dominate interfacial chemistry and electrodeposition barriers. We elucidate electrolyte effects facilitating or impeding Li+ diffusion and deposition, and evaluate structural and energetic changes during the solvation complex pathway from the bulk to the anode surface… View more

Luis E. Camacho-Forero and Perla B. Balbuena, “Effects of Charged Interfaces on Electrolyte Decomposition at the Lithium Metal Anode,” J. Power Sources, 472, 228449, (2020).

Lithium–Sulfur batteries are promising candidates to substitute conventional Li-ion batteries due to their higher energy density and reduced cost. However, several challenges related to the reactivity of the lithium metal anode have prevented this technology from becoming broadly commercialized. Lithium’s high reactive nature leads to the continuous decomposition of the electrolyte and the formation of the solid-electrolyte interphase (SEI) layer… View more 

Roberto C. Longo, Luis E. Camacho-Forero, and Perla B. Balbuena, “Charge-Mediated Cation Deposition on Metallic Surfaces,” J. Mater. Chem. A, 7, 8527-8539, (2019).

This work reveals the general mechanisms of Li+ cation partial reduction and further deposition under specific electrolyte conditions, and in the proximity of an electrified metal surface. The factors affecting the ion complexation and transport and resultant adsorbed structures are identified for various external electric fields and for several applied voltages. Using ab initio methods, we investigate the relation between solvent–salt structures and… View more

Luis E. Camacho-Forero and Perla B. Balbuena, “Exploring Interfacial Stability of Solid-State Electrolytes at the Lithium-Metal Anode Surface,” J. Power Sources, 396, 782-790, (2018).

Solid state electrolytes are promising materials to mitigate the issues derived from the extreme reactivity of the lithium metal anodes in Li-metal batteries. The main properties sought for this application are high ionic conductivity, low electronic conductivity, and high interfacial stability. Here we investigate a class of sulfides (Li10GeP2S12, Li2P2S6, β-Li3PS4, and Li7P3S11) that have shown relatively good ionic conductivities… View more