A carbon-based active material produced from apple leftovers and a material of layered oxides might help reduce the costs of future energy storage systems. Both were found to have excellent electrochemical properties and stand for the environmentally compatible and sustainable use of resources. Now, these materials are presented by researchers of the Helmholtz Institute Ulm in the journals “ChemElectroChem” and “Advanced Energy Materials.”
Sodium-ion batteries are not only far more powerful than nickel-metal hydride or lead acid accumulators, but also represent an alternative to lithium-ion technology, as the initial materials needed are highly abundant, easily accessible, and available at low cost. Hence, sodium-ion batteries are a very promising technology for stationary energy storage systems that play a central role in the transformation of the energy system and will be a highly attractive market in the future.
Now, researchers of the team of Professor Stefano Passerini of the Helmholtz Institute Ulm have made an important step towards the development of active materials for sodium-based energy storage systems. For the negative electrode, a carbon-based material was developed, which can be produced from the leftovers of apples and possesses excellent electrochemical properties. So far, more than 1000 charge and discharge cycles of high cyclic stability and high capacity have been demonstrated. This discovery represents an important step towards the sustainable use and exploitation of resources, such as organic waste.
The material developed for the positive electrode consists of several layers of sodium oxides. This active material goes without the expensive and environmentally hazardous element cobalt that is frequently used in active materials of commercial lithium-ion batteries. At the laboratory, the new active material, in which electrochemical energy storage proper takes place, reaches the same efficiency, cyclic stability, capacity, and voltage without any cobalt.
Both materials mark an important step towards the development of inexpensive and environmentallyfriendly sodium-ion batteries. The results are presented in two expert journals:
„Apple Biowaste-Derived Hard Carbon as a Powerful Anode Material for Na-Ion Batteries“ ChemElectroChem, doi: 10.1002/celc.201500437.
“Layered Na-Ion Cathodes with Outstanding Performance Resulting from the Synergetic Effect of Mixed P- and O-type Phases” Advanced Energy Materials, doi: 10.1002/aenm.201501555.
The deputy director of HIU, Stefano Passerini, is listed on the international citation ranking “Highly Cited Researchers 2015“ and thereby among the most influential researchers in his field.
Basis for this ranking by the media group Thomson Reuters are collected data on articles filed in the “Web of Science” from 2003 to 2013. Altogether, there are 120,000 articles in 21 main fields of science and the social sciences. Highly Cited Researchers presents around 3,200 researchers — ranking among the top 1% most cited for their subject field and year of publication. The frequency of citations by other researchers are an important indicator for the relevance of scientific papers. In 2015 Stefano Passerini was cited 1,800 times and other scientists referred to 352 of his papers. “The members of my research group were the key to achieve such recognition by other scientists and it shows that we are doing research in the right way”, Passerini clarified.
Since January 2014, he holds a professorship at the HIU and since July 2015 he is also deputy director of the institute. He has been working on the development of materials and systems for electrochemical energy storage for 30 years. His research efforts are focused on the fundamental understanding and the development of materials for lithium batteries, such as ionic liquids, polymer electrolytes, and electrode materials. He is co-author of almost 400 publications and has several newly-created materials patented.
For further information on the ranking, please visit: highlycited.com
Stefano Passerini, Bruno Scrosati, Rinaldo Raccichini and Alberto Varzi, members of the HIU-group Electrochemistry for Batteries, published a critical review of existing literature on graphene’s applications to batteries in the journal Nature Materials at the end of 2014. The progress article has been included as related article in the Nature Outlook edition on batteries. The authors of this edition demonstrate the possibilities of electrochemical energy storage in the future, identify the challenges for battery research and discuss new battery systems and materials.
As graphene has been lauded as a miracle material, the HIU-researchers resolved to analyse the previous findings. Initially they focused their review on experiments comparing graphene with graphite, the material currently most favored for negative electrodes in Lithium-ion batteries. But because they found only selective improvements, they chose to do a comprehensive literature review. The result was that a large percentage of publications focusing on the use of graphene for electrochemical batteries overestimated the potential capacity of graphene. In spite of enormous amounts of research data, it is not proven yet that the praising of graphene is justified. The researchers concluded that the major challenge in the future is to fill the gap between laboratory research and practical applications.
Please find the article in Nature Outlook here.
On 27th of July 2015 Helmholtz Institute hosted the international workshop “Towards next generation lithium-ion batteries” within the framework of the EU-funded project LISSEN. The main topic of the workshop concerned the latest developments in the field of the lithium-sulphur batteries. The representative of industry, the scientists from recognized research institutes and the project partners presented their recent results on the topic. The event was organised by the research group “Electrochemistry for Batteries” headed by the deputy director, Stefano Passerini, and visiting scientist Bruno Scrosati.
LISSEN is a large scale collaborative project, funded by the European Union Seventh Framework Programme (FP7), which aims to identify and develop nanostructured electrode and electrolyte materials to promote practical implementation of the very high energy lithium-sulphur battery.
The project is directed to the definition and testing of a new, lithium metal-free battery configuration based on the use of lithiated silicon as the anode and a nanostructured sulfur-carbon composite as the cathode. Such battery can offer an energy density at least three times higher than that available from the present lithium battery technology, a comparatively long cycle life, a much lower cost (replacement of cobalt-based with a sulfur-based cathode) and a high safety degree (no use of lithium metal).
Beginning the first of July 2015, Professor Maximilian Fichtner is replacing Professor Horst Hahn as the director of the Helmholtz Institute Ulm (HIU). Professor Stefano Passerini is replacing Prof. Fichtner as deputy director of the institute.
Prof. Maximilian Fichtner has conducted research on a variety of methods in energy storage which hold significant implications for the successful use of renewable energy resources and establishing the groundwork for electric mobility. During his time as director, Prof. Fichtner will implement the mission of the HIU as a national excellence center in battery research and contribute solutions to urgent problems in the energy supplies of the future. “We are on the correct path and will continue working on establishing the institute as one of the internationally recognized centers of research in batteries for the next and foreseeable generations,” he explains. With the great potential of its scientists, its cutting-edge infrastructure and the expertise of its four partners, the HIU is well-positioned to apply emerging technologies to innovative battery materials.
Prof. Fichtner’s doctoral work was in surface science and he subsequently established, among others, research groups in the areas of micro-process engineering for energy systems and nanomaterials for storage of hydrogen in solid states at the former Karlsruhe Research Center. For this work he was awarded the International Energy Agency (IEA) Project Prize in 2011. Prof. Fichtner currently leads a research group in material development at the HIU and, since April 2013, has been a professor in solid-state chemistry at the University of Ulm in the Department of Natural Sciences. He also leads a research group in energy storage systems at the Karlsruhe Institute of Technology (KIT) Institute of Nanotechnology.
Prof. Horst Hahn, starting in 2011, helped found the HIU, first as founding director and later as director. His term covered the entire initialization and construction phases of the institute, through developing the initial research strategy to moving into the new building in the fall of 2014. After his resignation, Prof Hahn will continue to lead his research group in solid electrolytes at the HIU. He also continues in his position as the director of the Institute of Nanotechnology (INT) at the KIT and is an honorary professor in India and China.
Translation by Melissa Pernice
Prof. Dr. Paul Heitjans, Institute for Physical Chemistry and Electrochemistry of the Gottfried Wilhelm Leibniz Universität Hannover, has been awarded with a senior research professorship for leading scientists by the federal state of Lower-Saxony. As holder of the Niedersachsenprofessur “Mobility of Li Ions in Solids” his research will be promoted another three more years after his retirement. The aim of the programme “Niedersachsenprofessur” is to promote scientists who exceeded the statutory age limit to continue their research. The federal state funds also seven other scientists.
Prof. Heitjans is spokesman of the research group FOR 1277 molife and of the Leibniz Research Centre ZFM – Centre for Solid State Chemistry and New Materials. He was appointed professor of physical chemistry and electrochemistry in 1987 at Hannover after his doctorate and his habilitation in physics in Heidelberg and Marburg.
As chairman of the HIU advisory board, which was founded in February of 2013, Prof. Heitjans counsels the board of directors on questions pertaining to research direction and strategies. The advisory board is made up of external professionals, researchers equipped with a wide range and depth of experience.
Bhaghavathi Parambath researches with an Alexander von Humboldt Research Fellowship from August 2015 onwards at HIU in the research group “Solid State Chemistry” leaded by Prof. Maximilian Fichtner. For Bhaghavathi Parambath one of the most attractive electrochemical systems is the combination of magnesium with sulfur as it offers a theoretical energy density of over 3200 Wh l−1, which is beyond that of a lithium sulfur battery. Compared to the substantial progress made on lithium sulfur batteries, the magnesium sulfur battery is still in a very early stage of research and development. Bhaghavathi Parambath is trying to change this with his investigation on the fabrication of high capacity and long cyclic stability electrode materials for magnesium sulfur battery systems.
Bhaghavathi Parambath has received his doctorate in physics in August 2013 at the Indian Institute of Technology Madras in Chennai with an award for the best Ph.D. thesis. In his PhD thesis he investigated new materials for energy storage and energy conversion applications.
In providing Humboldt Research fellowships for postdoctoral researchers, the Alexander von Humboldt Foundation enables highly-qualified scientists and scholars from abroad who are just embarking on their academic careers and who completed their doctorates less than four years ago to spend extended periods of research in Germany. A Research Fellowship of Alexander von Humboldt Foundation is in demand as it leads often to a remarkable career in academia. According to a survey of the Humboldt Foundation, four out of five scientists were appointed to a full professorship within 20 years after their research period in Germany.
Since its discovery ten years ago and after receiving a surge of interest when its inventor received a Nobel Prize, graphene has been lauded as a miracle material. Developers planned to use graphene for flexible displays and improved data storage, as well as for high-performance batteries and electronic components. Researchers at the Helmholtz Institute Ulm (HIU) have completed a critical review of existing literature on graphene’s applications to batteries and published their findings in the journal Nature Materials.
Initially the researchers focused their review on experiments comparing graphene with graphite, the material currently most favored for negative electrodes in Lithium-ion batteries. But because they found only selective improvements, they chose to do a comprehensive literature review.
“A large percentage of publications focusing on the use of graphene for electrochemical batteries overestimated the potential capacity of graphene,” explains Stefano Passerini, leader of the research group “Electrochemistry for Batteries” at the HIU. Despite enormous amounts of research data, it wasn’t clear until now whether graphene truly has the potential to revolutionize multiple areas of our lives. “The major work required in the future is to fill the gap between laboratory research and practical applications,” clarifies Dr. Passerini.
Published article in Nature Materials: “The role of graphene for electrochemical energy storage”
Translation by Melissa Pernice
Thanks to a research stipend for experienced scientists from the Alexander von Humboldt Foundation, Professor Dr. Aimy Bazylak is able to use her Sabbatical Year to work as a guest researcher at the HIU. This award program supports the creation of long-term, collaborative research projects in Germany. Dr. Bazylak will be working together with Dr. Roswitha Zeis’ Young Investigator Group. Both researchers know each other from different conferences and expect promising results from their work together.
Dr. Bazylak’s work for some years has been focused on simulating and visualizing polymer electrolyte membrane (PEM) fuel cells. Her work is also focused on clean and sustainable energy and the separation and storage of CO2. Dr. Zeis develops high-temperature, polymer electrolyte membrane (PEM) fuel cells with phosphoric acid-doped polymer membranes. Through combining their expertise, both researchers hope to better understand and optimize the acid management of fuel cell systems.
Dr. Bazylak is a Professor in the Department of Mechanical Engineering at the University of Toronto, where she leads a team of talented junior researchers in the Thermofluids for Energy and Advanced Materials (TEAM) Laboratory. In 2012 Dr. Bazylak received the Ontario Ministry of Research and Innovation Early Researcher Award and in 2014 she was selected to be a member of the Canadian Society for Mechanical Engineering. She also works as the Associate Director of the Institute for Sustainable Energy and the NSERC CREATE Program in DGRC at the University of Toronto.
Translation by Melissa Pernice
Since January 1st 2015 Stefano Passerini serves as Editor-in-Chief of the Journal of Power Sources.
He holds a professorship at the HIU and is Principle Investigator of the research group Electrochemistry for Batteries. Since 1986 he has been working on the development of materials and systems for electrochemical energy storage. His research efforts are focused on the fundamental understanding and the development of materials for lithium batteries, such as ionic liquids, polymer electrolytes, and electrode materials. He is co-author of over 200 publications.
The Journal of Power Sources is the journal for researchers and technologists interested in all aspects of the science, technology and applications of sources of electrochemical power. Journal of Power Sources publishes original research and reviews about the science and applications of primary and secondary batteries, fuel cells, supercapacitors and photo-electrochemical cells.
