Martin Z. Bazant

Massachusetts Institute of Technology | MIT · Department of Chemical Engineering

Efficient and accurate learning of constitutive laws is crucial for accurately predicting the mechanical behavior of materials under complex loading conditions. Accurate model calibration hinges on a delicate interplay between the information embedded in experimental data and the parameters that define our constitutive models. The information encod...

Ionic liquids (ILs) are a promising class of electrolytes with a unique combination of properties, such as extremely low vapor pressures and nonflammability. Doping ILs with alkali metal salts creates an electrolyte that is of interest for battery technology. These salt-in-ionic liquids (SiILs) are a class of superconcentrated, strongly correlated,...

This work explores the complex hydrodynamics in magnetophoretic microfluidic processes, focusing on the interplay of forces and particle concentrations. The study employs a combined simulation and experimental approach to investigate...

Ion intercalation in intercalation solids is crucial for energy storage device, including Li-ion batteries. Despite significant advancements in understanding Li-ion diffusion and discoveries of new electrodes and electrolytes, the molecular process of ion intercalation across electrode-electrolyte interfaces remains poorly understood. Li intercalat...

Numerous publications describe the construction of data-driven models for cycle life prediction for lithium-ion batteries. The models with the highest predictive capability have been constructed using user-defined features, which are transformations of the raw input data, before applying feature selection and regression. The performance and interpr...

Operando non-destructive evaluation (NDE) techniques for Li-ion batteries are the gold standard for gaining physical insights into a cell. These methods have the potential to transform battery formation optimization, electrode and electrolyte characterization, and state-of-health (SoH) and remaining useable lifetime metrics by providing an orthogon...

The importance of accurate diagnostics in lithium-ion battery applications has received increasing emphasis, especially after the formation step to assess the quality of the solid-electrolyte interphase layer and before second-life usage to investigate whether the recycled battery meets safety and performance requirements [1, 2]. Among diagnostic m...

The solid electrolyte interphase (SEI) plays a key role in the aging of lithium-ion batteries. The engineering of advanced negative electrode materials to increase battery lifetime relies on accurate models of SEI growth, but quantitative measurement of SEI growth rates remains challenging due to their nanoscale heterogeneity and environmental sens...

Optimization of the formation step in lithium-ion battery manufacturing is challenging due to limited physical understanding of solid electrolyte interphase formation and the long testing time (~100 days) for cells to reach the end of life. We propose a systematic feature design framework that requires minimal domain knowledge for accurate cycle li...

Safety and maintaining high performance are key considerations during the operation of lithium-ion batteries. Battery degradation, in particular lithium plating and loss of active material, is often accelerated by fast charging. This study explores a strategy for the design of fast charging protocols that takes into account the influence of the var...

Ionic liquids (ILs) are an extremely exciting class of electrolytes for energy storage applications because of their unique combination of properties. Upon dissolving alkali metal salts, such as Li or...

Nucleic acids such as mRNA have emerged as a promising therapeutic modality with the capability of addressing a wide range of diseases. Lipid nanoparticles (LNPs) as a delivery platform for nucleic acids were used in the COVID-19 vaccines and have received much attention. While modern manufacturing processes which involve rapidly mixing an organic...

Li-ion batteries and fuel cells play essential roles in electrifying transportation. Central to the electrochemical systems is the electrode-electrolyte interface, where (electro)chemical surface reactions or intercalation occur, and its thermodynamic and kinetic properties determine the energy density, power density, and lifetime of the electroche...

Diagnostics of lithium-ion batteries are frequently performed in battery management systems for optimized operation of lithium-ion batteries or for second-life usage. However, attempting to extract dominant degradation information requires long rest times between diagnostic pulses, which compete with the need for efficient diagnostics. Here, we des...

The electrochemical separation of charged species is becoming increasingly relevant for industry. A developing set of promising technologies in this space centers around the utilization of deionization shocks in porous, charged materials. To date, primarily homogeneous media have been investigated; however, heterogeneities are present in many porou...

Health monitoring, fault analysis, and detection are critical for the safe and sustainable operation of battery systems. We apply Gaussian process resistance models on lithium iron phosphate battery field data to effectively separate the time-dependent and operating point-dependent resistance. The data set contains 29 battery systems returned to th...

Lithium-ion batteries change their geometric dimensions during cycling as a macroscopic result of a series of microscale mechanisms, including but not limited to diffusion-induced expansion/shrinkage, gas evolution, growth of solid-electrolyte interphase, and particle cracking. Predicting the nonlinear dimensional changes with mathematical models i...

Lithium-ion batteries are powering a revolution in electrification, but the underlying intercalation mechanism at the electrified interface remains poorly understood. Here, we provide experimental and theoretical evidence that lithium intercalation occurs by coupled ion-electron transfer (CIET), in which classical ion transfer from the electrolyte...

Interface engineering remains a largely underexplored area and yet it holds the keys to high performance Li-ion batteries. It is the charge transfer across electrode-electrolyte interfaces, its inefficient energetics and sluggish kinetics that are oftentimes significant obstacles for achieving fast charging and high power regimes without compromisi...

Industry-standard diagnostic methods for rechargeable batteries, such as hybrid pulse power characterization (HPPC) tests for hybrid electric vehicles, provide some indications of state of health (SoH), but lack a physical basis to guide protocol design and identify degradation mechanisms. We develop a physics-based theoretical framework for HPPC t...

Diagnostics of lithium-ion batteries are frequently performed in battery management systems for optimized operation of lithium-ion batteries or for second-life usage. However, attempting to extract dominant degradation information requires long rest times between diagnostic pulses, which compete with the need for efficient diagnostics. Here, we des...

Ionic liquids (ILs) are a promising class of electrolytes owing to a unique combination of properties, such as extremely low vapour pressures, non-flammability and being universal solvents. Doping ILs with alkali metal salts creates an electrolyte that is of interest for batteries, among others. These salt-in-ionic liquids (SiILs) are a class of su...

Ionic liquids (ILs) are an extremely exciting class of electrolytes for energy storage applications because of their unique combination of properties. Upon dissolving alkali metal salts, such as Li or Na based salts, with the same anion as the IL, an intrinsically asymmetric electrolyte can be created for use in batteries, known as a salt-in-ionic...

Lithium plating during fast charging of porous graphite electrodes in lithium-ion batteries accelerates degradation and raises safety concerns. Predicting lithium plating is challenging due to the close redox potentials of lithium reduction and intercalation, obscured by the nonlinear dynamics of electrochemically driven phase separation in hierarc...

We consider laminar, fully developed, Poiseuille flows of liquid in the Cassie state through diabatic, parallel-plate microchannels symmetrically textured with isoflux ridges. Via matched asymptotic expansions, we develop expressions for (apparent hydrodynamic) slip lengths and Nusselt numbers. Our small parameter ( $\epsilon$ ) is the pitch of the...

Industry-standard diagnostic methods for rechargeable batteries, such as hybrid pulse power characterization (HPPC) tests for hybrid electric vehicles, provide some indications of state of health (SoH), but lack a physical basis to guide protocol design and identify degradation mechanisms. We develop a physics-based theoretical framework for HPPC t...

High-dimensional linear regression is important in many scientific fields. This article considers discrete measured data of underlying smooth latent processes, as is often obtained from chemical or biological systems. Interpretation in high dimensions is challenging because the nullspace and its interplay with regularization shapes regression coeff...

As the design of single-component battery electrodes has matured, the battery industry has turned to hybrid electrodes with blends of two or more active materials to enhance battery performance. Leveraging the best properties of each material while mitigating their drawbacks, multi-component hybrid electrodes open a vast new design space that could...

Reaction rates at spatially heterogeneous, unstable interfaces are notoriously difficult to quantify, yet are essential in engineering many chemical systems, such as batteries ¹ and electrocatalysts ² . Experimental characterizations of such materials by operando microscopy produce rich image datasets 3–6 , but data-driven methods to learn physics...

All-solid-state batteries are attracting increasing interest due to their higher promised energy densities without the use of flammable liquid electrolytes. Two main challenges for solid-state batteries are contact loss and interphase formation; these play a central role in the quality of the solid-electrolyte–electrode interfaces. Here, we present...

Lithium plating during fast charging of porous graphite electrodes in lithium-ion batteries accelerates degradation and raises safety concerns. Predicting lithium plating is challenging due to the close redox potentials of lithium reduction and intercalation, obscured by the nonlinear dynamics of electrochemically driven phase separation in hierarc...

A general theory of coupled ion-electron transfer (CIET) is presented, which unifies Marcus kinetics of electron transfer (ET) with Butler-Volmer kinetics of ion transfer (IT). In the limit of large...

Lithium plating during fast charging of porous graphite electrodes in lithium-ion batteries accelerates degradation and raises safety concerns. Predicting lithium plating is challenging due to the close redox potentials of lithium reduction and intercalation, obscured by the dynamic resistance originated from the interplay of multiphase behavior an...

High-dimensional linear regression is important in many scientific fields. This article considers discrete measured data of underlying smooth latent processes, as is often obtained from chemical or biological systems. Interpretation in high dimensions is challenging because the nullspace and its interplay with regularization shapes regression coeff...

Climate change demands the development of clean energy technologies, where rechargeable batteries and fuel cells promise a bright future by integrating with solar or wind energy. Li-ion batteries and fuel cells also play essential roles in electrifying transportation in replacement of internal combustion engines. Central to these electrochemical sy...

Lithium-ion insertion kinetics fundamentally hinges upon phase transformation behavior during (dis)charging and understanding the rate-dependent kinetics is crucial for the development of high-power batteries. At high c-rates, kinetic hysteresis is amplified and phase evolution becomes heterogeneous and unpredictable. Specifically, discharge become...

Electrochemical Impedance Spectroscopy (EIS) is a key technique for taking a snapshot of an electrochemical system near equilibrium conditions. Due to the richness of the complex-valued dataset and its simple experimental operation, it is currently being investigated as a test to diagnosis battery health and degradation details. Nevertheless, chall...

This talk will review the basic physics of dendritic instabilities in electrodeposition and how they may be suppressed, in some cases, by controlling electrokinetic phenomena in the electrolyte or phase separation in the electrode: 1) It is shown both theoretically and experimentally that, if electrodeposition occurs in charged porous media above t...

As illustrated by the work of Ralph White, traditional methods of electrochemical engineering are based on human intelligence: Mathematical models encoding physical hypotheses are proposed, tested against experimental data and refined by fitting adjustable parameters. Artificial intelligence is beginning to challenge this paradigm, since prediction...

The mixed-ionic electronic conduction (MIEC) of gadolinium doped ceria (CGO) under reduced oxygen conditions makes it an excellent fuel electrode material for SOFC/SOEC applications. As part of a composite electrode (Ni/CGO), the nickel phase offers a fast electronic conduction pathway to the current collector and may act as an electrocatalyst at t...

Power sources of implantable cardioverter-defibrillators (ICD) require high energy density to ensure longevity and sufficient rate capability to provide high power pulses for treating abnormal heart rhythms. Such demands have led to the design of Li/CF x -SVO battery, which leverages the excellent energy density of carbon monofluoride (CF x ) and p...

In many schools of science and engineering where electrochemistry is beginning to play a major role in research and advanced study, it is still missing from the curriculum, especially at the undergraduate level. One way to address this problem and draw students into electrochemistry is to teach online. This talk will describe the teaching of electr...

Electrokinetic phenomena within complex structures are relevant in microfluidics. For example, ion concentration polarization is used for electrokinetic trapping for enhanced biosensing using molecular probes ¹ . Concentration polarization near ion-selective membranes also plays an important role in separation systems for desalination ² . Aside fro...

Sub-nanometer carbon nanotube porins (n-CNTP) have been shown to achieve high water permeation with significant permselectivity precluding anion transport. Therefore, n-CNTPs are useful model systems to probe and optimize the nanoscale transport phenomena relevant for selective ionic separations. Surprisingly, these n-CNTPs demonstrate a unique con...

The phase separation dynamics in graphitic anodes significantly affects lithium plating propensity, which is the major degradation mechanism that impairs the safety and fast charge capabilities of automotive lithium-ion batteries. In this study, we present comprehensive investigation employing operando high-resolution optical microscopy combined wi...

Phase separation during the lithiation of redox-active materials is a critical factor affecting battery performance, including energy density, charging rates, and cycle life. Accurate physical descriptions of these materials are necessary for understanding underlying lithiation mechanisms, performance limitations, and optimizing energy storage devi...

Lithium plating on porous graphite electrodes during the fast charging of lithium-ion batteries ac- celerates degradation and raises safety concerns. The onset of lithium plating is obscured by the reaction and transport resistance within the porous graphite electrodes. We extend the classic porous electrode theory by incorporating a Cahn-Hilliard...

Understanding the charge transfer processes at solid oxide fuel cell (SOFC) electrodes is critical to designing more efficient and robust materials. Activation losses at SOFC electrodes have been widely attributed to the ambipolar migration of charges at the mixed ionic–electronic conductor–gas interface. Empirical Butler–Volmer kinetics based on t...

Water and other polar liquids exhibit nanoscale structuring near charged interfaces. When a polar liquid is confined between two charged surfaces, the interfacial solvent layers begin to overlap, resulting in solvation forces. Here, we perform molecular dynamics simulations of polar liquids with different dielectric constants and molecular shapes a...

Machine learning (ML) is gaining popularity as a tool for materials scientists to accelerate computation, automate data analysis, and predict materials properties. The representation of input material features is critical to the accuracy, interpretability, and generalizability of data-driven models for scientific research. In this Perspective, we d...

As the design of single-component battery electrodes has matured, the battery industry has turned to hybrid electrodes with blends of two or more active materials to enhance battery performance. Leveraging the best properties of each material while mitigating their drawbacks, multi-component hybrid electrodes open a vast new design space that could...

In battery modeling, the electrode is discretized at the macroscopic scale with a single representative particle in each volume. This lacks the accurate physics to describe interparticle interactions in electrodes. To remedy this, we formulate a model that describes the evolution of degradation of a population of battery active material particles u...

Ion concentration polarization (CP, current‐induced concentration gradient adjacent to a charge‐selective interface) has been well studied for single‐phase mixed conductors (e.g., liquid electrolyte), but multiphase CP has been rarely addressed in literature. In our recent publication, we proposed that CP above certain threshold currents can flip t...

Conventional lithium-ion batteries, and many next-generation technologies, rely on organic electrolytes with multiple solvents to achieve the desired physicochemical and interfacial properties. The complex interplay between these properties can often be elucidated via the coordination environment of the cation. We develop a theory for the coordinat...

The global devastation of the COVID-19 pandemic has led to calls for a revolution in heating, ventilation, and air conditioning (HVAC) systems to improve indoor air quality (IAQ), due to the dominant role of airborne transmission in disease spread. While simple guidelines have recently been suggested to improve IAQ mainly by increasing ventilation...

Phase separation during the lithiation of redox-active materials is a critical factor affecting battery performance, including energy density, charging rates, and cycle life. Accurate physical descriptions of these materials are necessary for understanding underlying lithiation mechanisms, performance limitations, and optimizing energy storage devi...

Confined fluids and electrolyte solutions in nanopores exhibit rich and surprising physics and chemistry that impact the mass transport and energy efficiency in many important natural systems and industrial applications. Existing theories often fail to predict the exotic effects observed in the narrowest of such pores, called single-digit nanopores...

Electrochemical impedance spectroscopy (EIS) is a powerful tool in characterisation of processes in electrochemical systems, allowing us to elucidate the resistance and characteristic frequency of physical properties such as reaction and transport rates. The essence of EIS is the relationship between current and potential at a given frequency. Howe...

Recent advances in scientific machine learning have shed light on the modeling of pattern-forming systems. However, simulations of real patterns still incur significant computational costs, which could be alleviated by leveraging large image datasets. Physics-informed machine learning and operator learning are two new emerging and promising concept...

Single particle modeling, used in most battery simulations to describe intercalation and degradation, lacks the accurate physics to describe interactions between particles. To remedy this, we formulate a model that describes the evolution of degradation of a population of battery active material particles using ideas in population genetics of fitne...

Conventional lithium-ion batteries, and many next-generation technologies, rely on organic electrolytes with multiple solvents to achieve the desired physicochemical and interfacial properties. The complex interplay between these physicochemical and interfacial properties can often be elucidated via the coordination environment of the cation. We de...

Stabilised Li-rich and Li-poor surface domains formed during fast lithiation and delithiation, respectively, cause a large overpotential difference between discharging and charging.

Ion concentration polarization (CP, current-induced concentration gradient adjacent to a charge-selective interface) has been well studied for single-phase mixed conductors (e.g., liquid electrolyte), but multiphase CP has been rarely addressed in literature. In our recent publication, we proposed that CP above certain threshold currents can flip t...

Reaction rates at spatially heterogeneous, unstable interfaces are notoriously difficult to quantify, yet are essential in engineering many chemical systems, such as batteries [1] and electro-catalysts [2]. Experimental characterizations of such materials by operando microscopy produce rich image datasets [3, 4, 5, 6], but data driven methods to le...