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Increasing the fast charging capabilities and the driving range of electric vehicles are major goals in Li‐ion battery research to accelerate mass market adoption and reduce greenhouse gas emissions. This requires a fundamental understanding of the performance limiting factors to enable a knowledge‐based optimization of materials, electrode design and cell architectures. Herein, electrochemical fundamentals and recent insights concerning rate performance limitations of Li‐ion batteries at the electrode level are reviewed and discussed from charge and mass transport perspectives. The application of straightforward analytical and semi‐empirical models is highlighted in view of understanding specific performance limiting factors of electrodes for Li‐ion batteries based on experimental investigations. The summarized insights are discussed regarding promising improvement strategies to approach the practical limits of liquid electrolyte‐based Li‐ion batteries.

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Reuber, S., Jende-Strid, B., Wray, V. and Weissenbock, G. 1997. Accumulation of the chalcone isosalipurposide in primary leaves of barley flavonoid mutants indicates a defective chalcone isomerase. -Physiol. Plant. 101: 827-832.Mutants defective in flavonoid biosynthesis have become increasingly useful in elucidating the potential functions of these compounds in plants. To define the role of flavonoids as UV-B protectants in barley, we have screened part of the collection of proanthocyanidin-free barley mutants at the Carlsberg Research Laboratory, Copenhagen, Denmark. The four mutants ant 30-245, ant 30-272, ant 30-287 and ant 30-310 showed drastically reduced flavonoid levels in the primary leaf as compared to their corresponding parent varieties, and in addition accumulated a new mutant-specific phenolic compound which was identified as the chalcone glucoside isosalipurposide. Results from diallelic crosses indicate that all four mutants belong to the same new complementation group, which is designated as the Ant 30 locus. This gene has not earlier been described in barley. The data presented suggest a defective chalcone isomerase gene for the observed flavonoid pattern in leaves of ant 30 mutants.

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batteries are currently the most powerful energy storage technology, particularly for powering mobile electronic devices and electric vehicles. [1][2][3] Improved Li-ion batteries and alternatives, such as Li-metal batteries, [4] Li-S batteries, [5] and solid-state batteries, [6] have the potential to effectively address current civilization challenges such as global warming, environmental pollution, and depletion of fossil fuel resources, paving the way to a sustainable future. To this end, academia and industry around the world are conducting intensive research into various ways to improve existing batteries or bring novel concepts into application. The development of advanced materials and electrodes is one of the most important steps in this process. [7][8][9][10] On a daily basis, reports of improved active materials or electrode architectures that significantly outperform established batteries are published in the scientific literature. However, the transfer of these innovations into practical application is rather rare. This may be due to difficulties in scaling the corresponding production routes to an industrially relevant level. Another possible reason is that promising performance metrics at the material level are not achieved in practical batteries, due to the different definition of performance parameters at the different technological levels, i.e., material, electrode, cell, system, etc.Various renowned scientists have already addressed these shortcomings in the presentation of performance data of new battery materials and electrodes in scientific literature [6,[11][12][13][14][15] and explicitly alert that extraordinary power claims for components used in batteries often do not hold up at the device level. These authors emphasize that reporting energy and power densities per weight of active material or electrode alone does not provide a realistic picture of the performance that an assembled device could achieve because it does not consider the weight of other necessary components. For example, it is well known that the rate capability scales with the electrode thickness. [16][17][18] Very thin electrodes (<20 µm) can be charged in a few minutes whereas thick electrodes (>100 µm) need several hours to achieve full capacity. When considering the specific capacity obtained at high rates in terms of mAh g -1 with respect to the mass of active material, the thin electrodes clearly outperform the thick ones. However, considering the power density Large-scale electrochemical energy storage is considered one of the crucial steps toward a sustainable energy economy. Science and industry worldwide are conducting intensive research into various ways to improve existing battery concepts or transferring novel concepts to application. The development of materials and electrodes is an essential step in this process. However, the evaluation of the achieved performance parameters and the comparison of the different studies at this technological level with regard to practical applications is challenging, since spec...

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The continuing rise of electric mobility is driving demand for lithium‐ion batteries to unprecedented levels. To ensure efficient production of high quality, yet affordable battery cells, while making the best use of available raw materials and processes, reasonable quality assurance criteria are needed. A step of particular importance, affecting all downstream processes, lies in electrode manufacturing including mixing, coating, drying, and calendering. Several classes of defects which originate in these processes are well‐known and detectable using various methods. The crucial point, however, lies in the quantification of their electrochemical significance, i. e., in an evaluation, which defect types, sizes and concentrations can be tolerated without impacting cell performance. Herein, we review the still scarce literature on that topic. It is found that, although the impact of some defects is quite well understood, others almost completely lack an evaluation of their criticality. We finally make suggestions for further studies paving the way to deduce knowledge‐based quality assurance criteria for the large variety of coating defects occurring in lithium‐ion battery electrodes.