Tobias Placke

Bio: Tobias Placke is an academic researcher from University of Münster. The author has contributed to research in topics: Electrolyte & Lithium. The author has an hindex of 40, co-authored 130 publications receiving 6550 citations.

Performance and cost of materials for lithium-based rechargeable automotive batteries

Abstract: It is widely accepted that for electric vehicles to be accepted by consumers and to achieve wide market penetration, ranges of at least 500 km at an affordable cost are required. Therefore, significant improvements to lithium-ion batteries (LIBs) in terms of energy density and cost along the battery value chain are required, while other key performance indicators, such as lifetime, safety, fast-charging ability and low-temperature performance, need to be enhanced or at least sustained. Here, we review advances and challenges in LIB materials for automotive applications, in particular with respect to cost and performance parameters. The production processes of anode and cathode materials are discussed, focusing on material abundance and cost. Advantages and challenges of different types of electrolyte for automotive batteries are examined. Finally, energy densities and costs of promising battery chemistries are critically evaluated along with an assessment of the potential to fulfil the ambitious targets of electric vehicle propulsion. Electrification is seen as the future of automotive industry, and deployment of electric vehicles largely depends on the development of rechargeable batteries. Here, the authors survey the state-of-the-art advances in active materials, electrolytes and cell chemistries for automotive batteries.

Lithium ion, lithium metal, and alternative rechargeable battery technologies: the odyssey for high energy density

Abstract: Since their market introduction in 1991, lithium ion batteries (LIBs) have developed evolutionary in terms of their specific energies (Wh/kg) and energy densities (Wh/L). Currently, they do not only dominate the small format battery market for portable electronic devices, but have also been successfully implemented as the technology of choice for electromobility as well as for stationary energy storage. Besides LIBs, a variety of different technologically promising battery concepts exists that, depending on the respective technology, might also be suitable for various application purposes. These systems of the “next generation,” the so-called post-lithium ion batteries (PLIBs), such as metal/sulfur, metal/air or metal/oxygen, or “post-lithium technologies” (systems without Li), which are based on alternative single (Na+, K+) or multivalent ions (Mg2+, Ca2+), are currently being studied intensively. From today’s point of view, it seems quite clear that there will not only be a single technology for all applications (technology monopoly), but different battery systems, which can be especially suitable or combined for a particular application (technology diversity). In this review, we place the lithium ion technology in a historical context and give insights into the battery technology diversity that evolved during the past decades and which will, in turn, influence future research and development.

Dual-graphite cells based on the reversible intercalation of bis(trifluoromethanesulfonyl)imide anions from an ionic liquid electrolyte

Abstract: Recently, dual-ion cells based on the anion intercalation into a graphite positive electrode have been proposed as electrochemical energy storage devices. For this technology, in particular electrolytes which display a high stability vs. oxidation are required due to the very high operation potentials of the cathode, which may exceed 5 V vs. Li/Li+. In this work, we present highly promising results for the use of graphite as both the anode and cathode material in a so-called “dual-graphite” or “dual-carbon” cell. A major goal for this system is to find suitable electrolyte mixtures which exhibit not only a high oxidative stability at the cathode but also form a stable solid electrolyte interphase (SEI) at the graphite anode. As an electrolyte system, the ionic liquid-based electrolyte mixture Pyr14TFSI-LiTFSI is used in combination with the SEI-forming additive ethylene sulfite (ES) which allows stable and highly reversible Li+ ion and TFSI− anion intercalation/de-intercalation into/from the graphite anode and cathode, respectively. By addition of ES, also the discharge capacity for the anion intercalation can be remarkably increased from 50 mA h g−1 to 97 mA h g−1. X-ray diffraction studies of the anion intercalation into graphite are conducted in order to understand the influence of the electrolyte additive on the graphite structure and on the cell performance.

Best Practice: Performance and Cost Evaluation of Lithium Ion Battery Active Materials with Special Emphasis on Energy Efficiency

Abstract: In order to increase the energy content of lithium ion batteries (LIBs), researchers worldwide focus on high specific energy (Wh/kg) and energy density (Wh/L) anode and cathode materials. However, most of the attention is primarily paid to the specific gravimetric and/or volumetric capacities of these materials, while other key parameters are often neglected. For practical applications, in particular for large size battery cells, the Coulombic efficiency (CE), voltage efficiency (VE), and energy efficiency (EE) have to be considered, which we point out in this work by comparing numerous LIB active materials. For all presented active materials, energy inefficiency is mainly caused by a voltage inefficiency, which in turn is affected by the voltage hysteresis between the charge and discharge curves. Hence, this study could show that materials with larger voltage hysteresis such as the ZnFe2O4 (ZFO) anode or the Li-rich cathode material exhibit also a lower VE and EE than for instance graphite and LiNi0.5Mn1...

I and i

Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

"Water-in-salt" electrolyte enables high-voltage aqueous lithium-ion chemistries.

Abstract: Lithium-ion batteries raise safety, environmental, and cost concerns, which mostly arise from their nonaqueous electrolytes. The use of aqueous alternatives is limited by their narrow electrochemical stability window (1.23 volts), which sets an intrinsic limit on the practical voltage and energy output. We report a highly concentrated aqueous electrolyte whose window was expanded to ~3.0 volts with the formation of an electrode-electrolyte interphase. A full lithium-ion battery of 2.3 volts using such an aqueous electrolyte was demonstrated to cycle up to 1000 times, with nearly 100% coulombic efficiency at both low (0.15 C) and high (4.5 C) discharge and charge rates.

Performance and cost of materials for lithium-based rechargeable automotive batteries

Abstract: It is widely accepted that for electric vehicles to be accepted by consumers and to achieve wide market penetration, ranges of at least 500 km at an affordable cost are required. Therefore, significant improvements to lithium-ion batteries (LIBs) in terms of energy density and cost along the battery value chain are required, while other key performance indicators, such as lifetime, safety, fast-charging ability and low-temperature performance, need to be enhanced or at least sustained. Here, we review advances and challenges in LIB materials for automotive applications, in particular with respect to cost and performance parameters. The production processes of anode and cathode materials are discussed, focusing on material abundance and cost. Advantages and challenges of different types of electrolyte for automotive batteries are examined. Finally, energy densities and costs of promising battery chemistries are critically evaluated along with an assessment of the potential to fulfil the ambitious targets of electric vehicle propulsion. Electrification is seen as the future of automotive industry, and deployment of electric vehicles largely depends on the development of rechargeable batteries. Here, the authors survey the state-of-the-art advances in active materials, electrolytes and cell chemistries for automotive batteries.

Batteries and fuel cells for emerging electric vehicle markets

Abstract: Today’s electric vehicles are almost exclusively powered by lithium-ion batteries, but there is a long way to go before electric vehicles become dominant in the global automotive market. In addition to policy support, widespread deployment of electric vehicles requires high-performance and low-cost energy storage technologies, including not only batteries but also alternative electrochemical devices. Here, we provide a comprehensive evaluation of various batteries and hydrogen fuel cells that have the greatest potential to succeed in commercial applications. Three sectors that are not well served by current lithium-ion-powered electric vehicles, namely the long-range, low-cost and high-utilization transportation markets, are discussed. The technological properties that must be improved to fully enable these electric vehicle markets include specific energy, cost, safety and power grid compatibility. Six energy storage and conversion technologies that possess varying combinations of these improved characteristics are compared and separately evaluated for each market. The remainder of the Review briefly discusses the technological status of these clean energy technologies, emphasizing barriers that must be overcome. Recent years have seen significant growth of electric vehicles and extensive development of energy storage technologies. This Review evaluates the potential of a series of promising batteries and hydrogen fuel cells in their deployment in automotive electrification.