Batteries & Fuel Cells

To enable the prospects for significant market penetration, we are pursuing a step change in energy density. We conduct “enabling lithium metal” research, which is part of the U.S. Department of Energy's (DOE's) Vehicle Technology Office initiative referred to as "Beyond Li-ion." Lithium metal batteries hold twice as much electricity as today’s lithium-ion batteries. Beyond Li-ion envisions using lithium metal as the anode in place of the graphite presently used in lithium-ion cells. A direct replacement of equivalent capacity would result in a ten-fold reduction in the mass of the anode-active material and a nearly equal reduction in the volume of the anode.

This initiative focuses on understanding the fundamentals of lithium metal plating and devising ways to prevent dendrite formation, which occurs when the lithium metal interacts with the electrolyte. This reduces the coulombic efficiency, which is the efficiency of the transfer of lithium ions between the anode and cathode during the charging and discharging process.

One of the more popular approaches for achieving these goals is the formation of microstructures that allow for the accumulation of lithium without the formation of dendrites or mossy structures. Also being pursued are solid electrolytes, both organic and inorganic, that physically prevent the growth of dendrites during plating. A third, hopeful approach is the development of a liquid electrolyte that simultaneously promotes smooth deposition and is almost completely inert to lithium reduction.

The Kostecki Research Group contributes to this effort in its focus on Electrochemical Energy Storage. They are developing better anode, cathode, and solid electrolyte materials for lithium-ion batteries and characterizing the chemistry of performance-limiting processes under different conditions. In addition, they study novel battery and supercapacitor chemistries.

The Balsara Lab also contributes to this effort by designing polymer materials for lithium-ion batteries. They study self-assembly and transport properties of nanostructured polymer materials for applications such as lithium batteries. Their objective is to increase the selective transport of the desired species— lithium ions— through the membrane. Their work includes electrochemical characterization of different polymer electrolytes, studying the phase behavior of different block copolymers, along with observing the formation and growth of lithium dendrites through these electrolytes. This work involves materials design, synthesis, characterization, and performance evaluation in applications.    

The Ceder Group contributes to improving Li-ion batteries by developing robust computational approaches for the prediction of voltage profiles, thermal stabilities, ionic conductivities, and lithium percolation

LITHIUM-SULFUR BATTERIES

Sulfur has a theoretical first charge capacity of over 1675 mAh/g, ten times the capacity for lithium than today's lithium-ion cathodes. An issue concerning sulfur is that it forms soluble lithium-polysulfide components in liquid electrolytes as it is lithiated from sulfur to lithium sulfide. These soluble components can migrate to the anode in the liquid electrolyte resulting in coulombic inefficiency and loss of sulfur. Also, lithium sulfide, which makes up at least 50% of a cell's capacity during the last stage of lithiation, is non-soluble and an insulator, both ionic and electronic. Despite these challenges, efficiency would not be a problem if our enabling lithium metal activities resulted in a suitable solid electrolyte.

The Gau Liu Research Lab in the Applied Energy Materials Group has discovered a new type of polymer that can be used as a binder in a lithium-sulfur battery and allows valuable electrode materials to be recycled. (See news article: "Material Discovery Makes Lithium-Sulfur Batteries More Sustainable.") The lab combines synthetic chemistry, composite engineering, and electrochemistry to solve interdisciplinary problems in energy generation, storage, and usage. They use advanced diagnostics to understand fundamental and critical issues in energy systems, as well as synthetic techniques to develop new materials that improve overall system performance. Their work on lithium-sulfur batteries contributes to the Sulfur Electrode research task of the Advanced Battery Materials Research program.

THERMAL MANAGEMENT OF BATTERIES

Effective heat dissipation in batteries is important for a variety of reasons, including performance, reliability, safety, and fast charging. Currently, the thermal management of battery cells is provided at the system level using external cooling equipment, resulting in complex system-level designs and reduced effective energy densities.

The Prasher Lab focuses on providing battery cell materials-level thermal solutions by enhancing thermal transport material properties. Their approach is to: 1) identify thermal bottlenecks in Li-ion batteries during operation; 2) explore various techniques to minimize the identified thermal bottlenecks without compromising electrical performance; and 3) detect the onset of lithium plating.

The Prasher Lab is part of the Thermal Science Group, a science-to-systems lab conducting research in manipulating matter at nanoscale dimensions for novel applications in a multitude of thermal, solar, and electrochemical energy devices and systems. They combine theoretical, computational, and experimental techniques to understand energy conversion, storage, and transport. 

One challenge to finding better materials is understanding why the materials we have do not work as we would like on the nano and atomic levels. For this reason, DOE generously supports the development of techniques that can lead to new understanding and inspire innovative solutions for improving the materials. The national labs are home to some of the most powerful experimental resources in the world, from synchrotron light sources and spectrometers to powerful microscopes and supercomputer clusters. Finding new ways to use these instruments to understand electrochemical phenomena from an ex situ, in situ, and in operando basis is core to DOE’s mission.

The Materials Project serves as a premier model for the transition to a smart approach to discovery. Scientists can now design new materials with computers and estimate their properties, such as diffusion of ions, voltage for intercalation, and capacity for ions of any size. Researchers can calculate the stability of electrolytes and determine the reaction products. This capability supports finding new cathode materials with high voltage, high capacity, and low scarce-metal content and new electrolytes that are compatible with lithium. (See news article: "Searching for Photocathodes that Convert CO₂ into Fuels.")

The Persson Group runs the Materials Project and studies the physics and chemistry of materials using atomistic computational methods and high-performance computing technology. They focus on materials for energy applications, such as battery electrode materials, electrolytes, photocatalysts, and thermoelectric. (See interview with Materials Project founder and director, Kirsten Persson.)

MATERIALS DISCOVERY VIA HIGH-THROUGHPUT COMPUTING, DATA MINING, AND THE MATERIALS PROJECT

The development of new functional materials remains, despite the rapid pace of modern materials science, a laborious and painfully slow process. The fact that currently, it takes an average of 15 to 20 years for a successful material to move from the laboratory to the market speaks to the fundamental difficulty of traditional materials discovery and property characterization. The Ceder Group joins its high-throughput computation efforts with the data sets and tools of the Materials Project to fundamentally change how this process works, moving from isolated insight and serendipity to the systematic prediction and characterization of novel materials.

To this end, they are pursuing two tightly linked research directions: 1) the automated, quantum mechanical characterization of known and new materials and their properties, which they term ‘high-throughput computing’; and 2) the prediction of new materials and properties through data mining. They have already applied these two methods to the discovery of new materials for Li-ion batteries, photocatalysts, thermoelectrics, piezoelectrics, and other functional materials. They are actively engaged in developing data mining and high-throughput methodologies and applying these techniques to a range of physical problems and materials discovery.

ELECTRODES FOR NEXT-GENERATION BATTERIES

Since the electrodes (cathode and anode) of a battery determine its theoretical capacity, the choice of electrode materials is critical for both current-generation Li-ion batteries and next-generation battery technologies (including lithium-silicone and multivalent batteries). Even if a combination of anode and cathode has a high theoretical capacity, it is imperative to design electrodes to prevent degradation, a process that can be chemical, electrochemical, and, or mechanical in nature.

The Persson Group designs and studies electrode materials for a range of battery chemistries, tackling the challenges of both capacity and stability.

SODIUM-ION BATTERY MATERIALS DESIGN AND DISCOVERY 

Sodium-ion (Na-ion) batteries have vast potential as an inexpensive, geopolitically-neutral alternative to Li-based rechargeable batteries, mainly due to the global abundance and low cost of sodium-containing precursor materials. Due to their larger size, Na-ions can reversibly intercalate in more materials than Li-ions, giving a much broader chemical space in which to optimize electrode materials. This characteristic, together with sodium’s abundance, makes Na-ion batteries excellent candidates for large-scale energy storage.

The Ceder Group conducts computational and experimental studies to discover novel Na-ion electrodes and electrolytes, optimize materials, and understand the underlying physics governing material function. 

MULTIVALENT BATTERY MATERIALS DESIGN AND DISCOVERY

Multivalent ion batteries offer an exciting alternative in terms of the amount of energy they deliver, as well as their safety, manufacturing and disposal costs, and limited environmental impact. The Ceder Group collaborates with the Joint Center of Energy Storage Research to develop novel high-energy-density multivalent ion (magnesium, zinc, and calcium) batteries by leveraging high-throughput techniques, first-principles calculations, and sophisticated ab initio molecular dynamics.

SOLID-STATE Li CONDUCTORS AND ALL-SOLID-STATE BATTERIES

Safety issues are an immense concern in developing advanced energy storage technologies, especially Li-ion batteries, which contain a flammable organic liquid electrolyte. Replacing organic liquid electrolytes with a solid-state ionic conductor would improve battery safety and remove one of the few remaining barriers to even wider-scale use of Li-ion technology. Inorganic solid-state Li-ion conductors also benefit from many other advantages such as superior electrochemical, mechanical, and thermal stability; absence of leakage; and the possibility of battery miniaturization.

The Ceder Group has been developing and using advanced first-principles computational methodologies, combined with a materials genome approach, to search for and optimize novel Li-ion superionic conductors with superior ionic conductivity and chemical and electrochemical stability.

SOLID ELECTROLYTE POLYMER OPTIMIZATION

Electrochemical energy storage and conversion devices, including fuel cells, solar-fuel generators, and batteries, may provide clean and renewable sustainable-energy technologies for transportation applications. Common to all these devices is the optimization of multiple functionalities in the solid-electrolyte polymer, such as transport of ions, gases, and water in a mechanically stable matrix. 

The Kusoglu Research Lab is a multidisciplinary team of researchers focusing on the fundamental understanding of ion-containing polymers and functional soft matter for electrochemical devices and related chemical-mechanical phenomena for clean energy and environmental technologies. Their work informs the design of energy conversion devices such as the Redox Flow Battery, Polymer Electrolyte Fuel Cells, and Electrolyzers and Water-Splitting Devices. Their research involves structural characterization and modeling of the transport and mechanical properties of various ion-conductive polymers and composites, and their nanostructural characterization to establish a structure/function relationship. They work closely with the members of the Energy Conversion Group on transport phenomena and energy conversion technologies and have active collaborations with industry, academia, and national laboratories.

CONVERTING WASTE HEAT ENERGY

The Ramesh Lab researches thermoelectric and photovoltaic energy conversion in complex oxide heterostructures. They focus on developing the materials and know-how to enable pyroelectric energy conversion of waste heat to electrical energy, electrocaloric solid-state cooling, and thermally-driven electron emission. The lab combines state-of-the-art electron microscopy and soft X-ray spectromicroscopy with various proximal probes to probe the emergent phenomena in materials. They complement these tools with magnetotransport, ferroelectric and dielectric measurements on test structures fabricated in the Nanolab.

SOLID OXIDE FUEL CELLS

Solid oxide fuel cells (SOFCs) produce electricity by oxidizing a fuel. SOFC advantages include high heat and power efficiency, long-term stability, fuel flexibility, low emissions, and relatively low cost. However, high operating temperatures cause lengthy start-up times and mechanical and chemical compatibility issues.

Researchers in the Tucker Research Lab explore metal-supported solid oxide fuel cells (MS-SOFCs) to overcome some of these issues; these cells contain a thin electrolyte and active ceramic layers supported between porous stainless steel layers that provide mechanical strength and collect electronic current. The lab's symmetric-architecture MS-SOFC design provides cost and operational advantages, including mechanical ruggedness, tolerance to rapid thermal cycling, tolerance to oxidation of the fuel catalyst, and the ability to change the operating temperature in response to dynamic load requirements. They are developing MS-SOFCs for applications that require high efficiency and fast-start or intermittent operation, including electric vehicle range extenders. The focus of research is on cell performance, utilization of hydrocarbon fuels, and scale-up to commercially-relevant cell size. They use in situ electrochemical testing, advanced diagnostics, and post-mortem analysis to determine limitations to cell performance and lifetime and inform efforts to improve device performance metrics, cost, and manufacturability.,

Researchers in the Adam Weber Research Lab have shown the potential for using metal-supported solid oxide electrolysis cells (SOECs) to produce hydrogen. (See this news article: weberlab.lbl.gov/news/tucker-lab-publication-top-article.)

FUEL-CELL MODELING

The Adam Weber Research Lab models the operation of various fuel-cell and electrolyzer components and cells focusing on transport phenomena and reaction kinetics. They explore the physical mechanisms governing polymer-electrolyte fuel cells, ionomers, and electrolyzers to reduce costs and increase performance and durability under relevant conditions. The group broadly explores electrochemical-based energy-conversion materials and assemblies across various technology platforms and applications. As a multidisciplinary team of electrochemists, chemical engineers, mechanical engineers, theorists, and material scientists, they work extensively with industry, academia, and national laboratories. They are key partners within the Fuel Cell Consortium for Performance and Durability, HydroGen, Advanced Water Splitting Materials, and the Joint Center for Artificial Photosynthesis.

JCAP is the nation’s largest research program dedicated to the development of an artificial solar-fuels generation science and technology. Established in 2010 as a DOE Energy Innovation Hub, it aims to find new and effective ways to produce fuels using only sunlight, water, and carbon dioxide. JCAP is led by a team from the California Institute of Technology (Caltech) and brings together more than 100 world-class scientists and engineers from Caltech and its lead partner, Lawrence Berkeley National Laboratory (Berkeley Lab). JCAP also draws on the expertise and capabilities of key partners from the University of California campuses at Irvine (UCI) and San Diego (UCSD), and the SLAC National Accelerator Laboratory. 

(See news story: “A ‘Silver Bullet’ for the Chemical Conversion of Carbon Dioxide”)

Founded in 2012, JCESR is one of the DOE’s Energy Innovation Hubs. Its mission is to design and build transformative materials enabling next-generation batteries that satisfy all the performance metrics for a given application. JCESR will achieve its mission by designing and building materials from the bottom up, atom-by-atom and molecule-by-molecule, where each atom or molecule plays a prescribed role in producing targeted overall materials behavior.

Berkeley Lab is one of 18 partner organizations of the JCESR.

The Advanced BMR Program within the Office of Energy Efficiency and Renewable Energy comprises seven research tasks aimed at the development of advanced batteries for electric vehicles. Principal investigators from the national labs, universities, and industry partners contribute to these efforts. Berkeley Lab scientists undertake research in four of these tasks: Sulfur Electrodes, Modeling, Diagnostics, and Liquid/Polymer Solid-State Electrolytes.

HydroGEN accelerates research, development, and deployment of advanced water splitting technologies for clean, sustainable hydrogen production. Berkeley Lab joins five other DOE national laboratories in this consortium to address advanced water splitting materials challenges by making unique, world-class national lab capabilities in photoelectrochemical, solar thermochemical, and low- and high-temperature electrolytic water splitting more accessible to academia, industry, and other national labs. HydroGEN is part of the DOE Energy Materials Network (EMN) and is funded by DOE’s Fuel Cell Technologies Office.

FC-PAD coordinates national laboratory activities related to fuel cell performance and durability, provides technical expertise, and integrates activities with industrial developers. The cost and durability of current polymer electrolyte membrane fuel cells (PEMFCs) are major barriers to their commercial use for stationary or transportation power generation. By bringing together proven expertise in the core national laboratories and building on existing capabilities, FC-PAD plans to demonstrate world-class improvements in fuel cell performance and durability that exceed the 2020 targets set by the U.S. Department of Energy Fuel Cell Technologies Office (FCTO).

FC-PAD's core lab team consists of five national laboratories and leverages a multi-disciplinary team and capabilities to accelerate improvements in PEMFC performance and durability. Los Alamos National Laboratory is the consortium lead; Lawrence Berkeley National Laboratory is the deputy lead; and Argonne National Laboratory, National Renewable Energy Laboratory, and Oak Ridge National Laboratory are technical partners. Innovations from the broader research and development community will be brought into the FC-PAD consortium through funding opportunity announcements and national lab partnerships.

Million Mile Fuel Cell Truck is a DOE-funded consortium formed by five primary national labs to overcome durability and efficiency challenges in PEMFCs for heavy-duty applications with an initial focus on long-haul trucks. The consortium coordinates national laboratory activities related to fuel-cell efficiency and durability, provides technical expertise, and harmonizes activities with industrial developers across the Hydrogen Fuel Cell and Technology Office's heavy-duty vehicle PEMFC portfolio, which is located in DOE's Office of Energy Efficiency & Renewable Energy, thus amplifying their impact.

NERSC is a DOE Office of Science User Facility that serves as the primary high-performance computing center for scientific research sponsored by the Office of Science. Located at Berkeley Lab, NERSC serves more than 7,000 scientists at national laboratories and universities researching a wide range of problems in combustion, climate modeling, fusion energy, materials science, physics, chemistry, computational biology, and other disciplines.

NERSC is known as one of the best-run scientific computing facilities in the world. It provides some of the largest computing and storage systems available anywhere, but what distinguishes the center is its success in creating an environment that makes these resources effective for scientific research. NERSC systems are reliable and secure, and provide a state-of-the-art scientific development environment with the tools needed by the diverse community of NERSC users. NERSC offers scientists intellectual services that empower them to be more effective researchers. For example, many of our consultants are themselves domain scientists in areas such as material sciences, physics, chemistry, and astronomy, and are well-equipped to help researchers apply computational resources to specialized science problems.

Harnessing the power of supercomputing and state-of-the-art electronic structure methods, the Materials Project provides open, web-based access to computed information on known and predicted materials, as well as powerful analysis tools to inspire and design novel materials. (See: an interview with Materials Project founder and director, Kirsten Persson.)

The development of the Materials Project is supported by the DOE through its Office of Science, via the Basic Energy Sciences (BES) and Advanced Scientific Computing Research (ASCR) programs, and through its Office of Energy Efficiency and Renewable Energy (EERE), via the Battery Materials Research (BMR) program. A notable source of support within DOE-BES is the Joint Center for Energy Storage Research (JCESR). The Materials Project is also supported by a Laboratory Directed Research and Development grant from Berkeley Lab and by the U.S. National Science Foundation (NSF) via the Data Infrastructure Building Blocks (DIBBS) program. Disseminated science is supported by DOE (BES and BMR), NSF, Gillette, Volkswagen, Umicore, and Bosch.

The ALS, located inside Berkeley Lab’s signature dome, is a DOE-funded synchrotron facility that provides users from around the world access to the brightest beams of soft x-rays, together with hard x-rays and infrared, for scientific research and technology development. Research techniques used at the ALS include spectroscopy, microscopy/imaging, and scattering/diffraction. The ALS thrust areas are organized around cross-cutting themes and include scientists from the ALS and collaborating Berkeley Lab divisions. The thrust areas supporting scientists researching next-generation batteries and fuel cells are Complex Materials & Interfaces and Chemical Transformations.

Supported by the DOE Office of Basic Energy Sciences (BES) through their Nanoscale Science Research Center (NSRC) program, the Molecular Foundry is a national User Facility for nanoscale science serving over a thousand academic, industrial, and government scientists around the world each year. The Molecular Foundry features world-class scientists with expertise across a broad range of disciplines and state-of-the-art, often one-of-a-kind, instrumentation.

For batteries and fuel cells researchers, one of the most important facilities at the Foundry is the National Center for Electron Microscopy (NCEM). Established in 1983 to maintain a forefront research center for electron microscopy, it merged with the Molecular Foundry in 2014 to take advantage of growing scientific and organizational synergies. NCEM at the Foundry features 10 electron microscopes, many of which are world-leading. NCEM focuses on the cutting-edge instrumentation, techniques, and expertise required for advanced electron beam characterization of materials at high spatial resolution.