Improving the production of batteries for electric vehicles

A research lead by the company BASF has characterized a new methodology to produce nickel-rich cathode materials used in lithium-ion batteries that optimizes the conventional production process. The proposed model leads to an increase in throughput by a factor of three, representing a considerable increase in the efficiency of future cathode active materials production for battery electric vehicles. The contributions of the MSPD beamline at ALBA have been key in these findings.

Batteries of electric vehicles still have not reached full cost competitiveness with respect to cars powered by combustion engines. This is mainly due to the increase in the cost of the raw materials used to produce the cathode of the batteries. In the search for low-cost materials for cathodes, the research on efficient manufacturing is of utmost importance.

A research led by the company BASF, in collaboration with different German universities and research centers, has studied how to optimize the conventional production process of nickel-rich cathode materials for lithium-ion batteries. This process is a thermal treatment called calcination. More specifically, researchers wanted to obtain a deeper understanding of the lithiation mechanism itself. And also, whether a two-stage calcination process, including a partial-lithiation step, can be used to synthesize cathode active materials with similar properties to those of a conventional one-stage calcination protocol.

The proposed calcination concept leads to an increase in throughput by a factor of three, increasing the efficiency of future cathode active materials production without modifying their physico-chemical properties and electrochemical behavior. Moreover, further advantages of the partial-lithiation process regarding homogeneity of the composition and crystallite size of the cathode active materials are believed to come into view as soon as large-scale sample amounts are investigated, which will be part of future work.

To further characterize the samples after the partial-lithiation step, synchrotron X-ray powder diffraction (XRD) measurements were performed at the MSPD beamline of the ALBA Synchrotron. This is the first report on the composition of the lithium-containing residual needles, which are indicative of an incomplete reaction. By combination of XRD, and other characterization techniques, the presence of Lithium hydroxide was confirmed in the samples prepared with the conventional method but not on the samples obtained with the novel two-stage methodology.

Read more on the ALBA website

NSLS-II Researchers Win 2022 Microscopy Today Innovation Award

The team developed a set of bonded x-ray lenses to overcome a long-standing alignment issue, making nanometer resolution more accessible than ever before.

Scientists at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory received the 2022 Microscopy Today Innovation Award for their development of a system with bonded x-ray lenses that make nanoscale resolution more accessible than ever before. When the team at the National Synchrotron Light Source II (NSLS-II), a DOE Office of Science user facility, tested the new lens system, they achieved a resolution down to approx. 10 nanometers.

“We need technologies of the future to tackle some of society’s biggest challenges — from microelectronics to tiny qubits for quantum computers to longer-lasting batteries,” said John Hill, NSLS-II Director. “However, to develop these new devices, researchers need to study materials at the nanoscale. And this where these new lenses really come into their own. They make focusing hard x-ray beams down to a few nanometers much easier than ever before. By using the very focused x-ray beams that these lenses produce, we can reveal the function, structure, and chemistry of next-generation materials on the nanoscale. This crucial breakthrough was only made possible through years of intense work by experts—who are world-leaders in their respective fields—working together. I am delighted that their work has been recognized by this award and very proud to have this new lens system at NSLS-II.”

Read more on the Brookhaven National Laboratory website

Image: The members of the development team in front of NSLS-II. From left to right: Yong Chu, Hanfei Yan, Weihe Xu, Wei Xu, Xiaojing Huang, Ming Lu, Natalie Bouet, Evgeny Nazaretski. Not pictured: Juan Zhou and Maxim Zalalutdinov.

Copper doping improves sodium-ion battery performance

Although lithium-ion batteries currently drive the electronic world, sodium-ion batteries are gaining ground. A big plus is that sodium is more earth-abundant than lithium, which lowers costs and eases environmental and supply-chain concerns. As a result, enormous research efforts are underway to improve the energy density and cycling longevity of sodium-ion batteries.

One promising strategy to enhance energy density is to exploit additional sources of a key chemical reaction—oxidation reduction (redox)—in the battery’s cathode. In cathodes made of layered transition-metal oxides (the sodium ions move in and out from between the layers), it turns out that the oxygen component in the layers unexpectedly contributes to redox activity. Unfortunately, oxygen redox is frequently accompanied by irreversible oxygen behavior, resulting in both voltage and capacity decays.

To enhance oxygen redox reversibility, researchers doped a sodium-ion cathode material (Na0.6Mg0.3Mn0.7O2, or NMMO) with copper ions (Na0.6Mg0.15Mn0.7Cu0.15O2, or NMMCO). To understand how this affects the oxygen redox activity, they used a technique developed at Beamline 8.0.1 of the Advanced Light Source (ALS), called mapping of resonant inelastic x-ray scattering (mRIXS), to measure the effect of the copper doping at different states of charge.

“The mRIXS technique is one of the most powerful characterization tools available for detecting oxygen redox activities in battery electrodes,” said Liang Zhang, a professor at Soochow University and co-corresponding author of the published work. “With mRIXS, it’s also possible to quantify the reversibility of the oxygen redox reaction, which could greatly help us understand the oxygen evolution process during electrochemical cycling.”

Read more on the ALS website

Image: The partial substitution of Mg ions in the cathode with Cu ions, which possess similar ionic radii but distinct electronic states, led to strong Cu–O bonds (i.e., modulated transition metal (TM)–O covalency), which helped stabilize the lattice during repeated cycles. Light blue = Cu, dark green = Na, red = O, dark yellow = Mn, blue = Mg

X-rays capture ageing process in EV batteries

CLS researcher Toby Bond uses x-rays to help engineer powerful electric vehicle batteries with longer lifetimes. His research, published in The Journal of the Electrochemical Society, shows how the charge/discharge cycles of batteries cause physical damage eventually leading to reduced energy storage. This new work points to a link between cracks that form in the battery material and depletion of vital liquids that carry charge.

Bond uses the BMIT facility at the Canadian Light Source at the University of Saskatchewan to produce detailed CT scans of the inside of batteries. Working with Dr. Jeff Dahn at Dalhousie University, he specializes in batteries for electric vehicles, where the research imperative is to pack in as much energy as possible into a lightweight device.

“A big drawback to packing in more energy is that generally, the more energy you pack in, the faster the battery will degrade,” says Bond.

In lithium-ion batteries, this is because charging physically forces lithium ions between other atoms in the electrode material, pushing them apart. Adding more charge causes more growth in the materials, which shrink back down when the lithium ions leave. Over many cycles of this growing and shrinking, micro-cracks begin to form in the material, slowly reducing its ability to hold a charge.

Read more on the CLS website

Image: Toby Bond adjusts a battery sample on the BMIT beamline

Science’s great strength is the universal language

SSRL’s #LightSourceSelfie

Forrest Hyler is a PhD student at the University of California Davis and regular user of the Stanford Synchrotron Lightsource (SSRL). Forrest’s research involves exploring the structural and electronic properties of materials that are used as catalysts for carbon dioxide reduction in the lab. In his #LightSourceSelfie, Forrest describes his work as all encompassing as it involves studying materials related to a broad range of applications such as batteries, catalysis and the storage of radioactive materials. Forrest’s journey has involved a large range of scientists and he says, “The greatest part about science is that it’s kind of that universal language. You get to interact with people around the globe working together for a common goal to push science beyond the boundaries that we’ve ever been at before.”

Probing the Structure of a Promising NASICON Material

As physicists, materials scientists, and engineers continue striving to enhance and improve batteries and other energy storage technologies, a key focus is on finding or designing new ways to make electrodes and electrolytes.  One promising avenue of research involves solid-state materials, making possible batteries free of liquid electrolytes, which can pose fire and corrosion hazards.  An international group of researchers joined with scientists at Argonne National Laboratory to investigate the structure of crystalline and amorphous compounds based on the NASICON system, or sodium super-ion conductors. The work (using research carried out at the U.S. Department of Energy’s Advanced Photon Source [APS] and published in the Journal of Chemical Physics) reveals some substantial differences between the crystalline and glass phases of the NAGP system, which affect the ionic conductivity of the various materials.  The investigators note that the fraction of non-bridging oxygen (NBO) atoms appears to play a significant role, possibly altering the Na+ ion mobility, and suggest this as an area of further study.  The work provides fresh insights into the process of homogeneous nucleation and identifying superstructural units in glass ― a necessary step in engineering effective solid-state electrolytes with enhanced ionic conductivity. 

Because of their high ionic conductivity, materials with a NASICON structure are prime candidates for a solid electrolyte in sodium-ion batteries.  They can be prepared by a glass-ceramic route, which involves the crystallization of a precursor glass, giving them the usefulness of moldable bulk materials.  In this work, the research team specifically studied the NAGP system [Na1+xAlxGe2-x(PO4)3] with x = 0, 0.4 and 0.8 in both crystalline and glassy forms. Working at several different facilities, they used a combination of techniques, including neutron and x-ray diffraction, along with 27Al and 31P magic angle spinning and 31P/23Na double-resonance nuclear magnetic resonance spectroscopy.  The glassy form of NAGP materials was examined both in its as-prepared state and after thermal annealing, so that the changes on crystal nucleation could be studied.

Neutron powder diffraction measurements were performed at the BER II reactor source, Helmholtz-Zentrum Berlin, using the fine resolution powder diffractometer E9 (FIREPOD), followed by Rietveld analysis.  Further neutron diffraction observations were conducted at the Institut Laue-Langevin using the D4c diffractometer and at the ISIS pulsed neutron source using the GEM diffractometer.  X-ray diffraction studies were performed at X-ray Science Division Magnetic Materials Group’s beamline 6-ID-D of the APS, an Office of Science user facility at Argonne National Laboratory. 

Read more on the APS website

Image: Fig. 1. NASICON crystal structure showing the tetrahedral P(4) phosphate motifs (purple), octahedral GeO6 motifs (cyan) and Na+ ions (green). Oxygen atoms are depicted in red.

Tiny Chip-Based Device Performs Ultrafast Manipulation of X-Rays

Researchers from the U.S. Department of Energy’s Advanced Photon Source (APS) and Center for Nanoscale Materials at Argonne National Laboratory have developed and demonstrated new x-ray optics that can be used to harness extremely fast pulses in a package that is significantly smaller and lighter than conventional devices used to manipulate x-rays. The new optics are based on microscopic chip-based devices known as microelectromechanical systems (MEMS).

“Our new ultrafast optics-on-a-chip is poised to enable x-ray research and applications that could have a broad impact on understanding fast-evolving chemical, material and biological processes,” said research team leader Jin Wang from the X-ray Science Division Time Resolved Research (TRR) Group at the APS. “This could aid in the development of more efficient solar cells and batteries, advanced computer storage materials and devices, and more effective drugs for fighting diseases.”

In new results published in The Optical Society OSA) journal Optics Express, the researchers demonstrated their new x-ray optics-on-a-chip device (Fig. 1), which measures about 250 micrometers and weighs just 3 micrograms, using the TRR Group’s 7-ID-C x-ray beamline at the APS. The tiny device performed 100 to 1,000 times faster than conventional x-ray optics, which that tend to be bulky.

Read more on the APS website

Image: Fig. 1. The photograph shows two MEMS elements on a single chip (A), with the active elements of 250 µm × 250 µm, and the micrograph (B) highlighting the size of the diffractive element, as compared to a section of human hair (C).

Researchers identify lithium hydride and a new form of lithium fluoride in the interphase of lithium metal anodes

A team of researchers led by chemists at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory has identified new details of the reaction mechanism that takes place in batteries with lithium metal anodes. The findings, published today in Nature Nanotechnology, are a major step towards developing smaller, lighter, and less expensive batteries for electric vehicles.

Recreating lithium metal anodes

Conventional lithium-ion batteries can be found in a variety of electronics, from smartphones to electric vehicles. While lithium-ion batteries have enabled the widespread use of many technologies, they still face challenges in powering electric vehicles over long distances.

To build a battery better suited for electric vehicles, researchers across several national laboratories and DOE-sponsored universities have formed a consortium called Battery500, led by DOE’s Pacific Northwest National Laboratory (PNNL). Their goal is to make battery cells with an energy density of 500 watt-hours per kilogram, which is more than double the energy density of today’s state-of-the-art batteries. To do so, the consortium is focusing on batteries made with lithium metal anodes.

Read more on the BNL website

Image: Brookhaven chemists Enyuan Hu (left, lead author) and Zulipiya Shadike (right, first author) are shown holding a model of 1,2-dimethoxyethane, a solvent for lithium metal battery electrolytes.

Graphite electrodes for rechargeable batteries investigated

Rechargeable graphite dual ion batteries are inexpensive and powerful.

A team of the Technical University of Berlin has investigated at the EDDI Beamline of BESSY II how the morphology of the graphite electrodes changes reversibly during cycling (operando).

The 3D X-ray tomography images combined with simultaneous diffraction now allow a precise evaluation of the processes, especially of changes in the volume of the electrodes. This can help to further optimise graphite electrodes.

Read more on the HZB website

Image: The tomogram during the charging process shows the spatially resolved changes in the graphite electrode thickness of a rechargeable aluminium ion battery in a discharged and charged state.

Credit: © HZB