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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 special electrodes and cell concepts are typically used at laboratory scale. In the present work, a straightforward computational tool (Ragone calculator) is provided to estimate performance data at the full cell level based on electrochemical measurements on electrodes. Application of the Ragone calculator simplifies the comparability of the different studies and allows an appropriate classification of the reported performance data. In addition, extrapolation of the results to the battery level can make a valuable contribution to assessing at early stages whether a development is target‐oriented or in which direction it needs to be advanced. [ABSTRACT FROM AUTHOR]

An intrinsic challenge of Li‐ion batteries is the instability of electrolytes against anode materials. For anodes with a favorably low operating potential, a solid‐electrolyte interphase (SEI) formed during initial cycles provides stability, traded off for capacity consumption. The SEI is mainly determined by the anode material, electrolyte composition, and formation conditions. Its properties are typically adjusted by changing the liquid electrolyte's composition. Artificial SEIs (Art‐SEIs) offer much more freedom to address and tune specific properties, such as chemical composition, impedance, thickness, and elasticity. Art‐SEIs for intercalation, alloying, conversion and Li metal anodes have to fulfil varying requirements. In all cases, sufficient transport properties for Li‐ions and (electro‐)chemical stability must be guaranteed. Several approaches for Art‐SEIs preparation have been reported: from simple casting and coating techniques to elaborated Phys‐Chem modifications and deposition processes. This review critically reports on the promising approaches for Art‐SEIs formation on different type of anode materials, focusing on methodological aspects. The specific requirements for each approach and material class, as well as the most effective strategies for Art‐SEI coating, are discussed and a roadmap for further developments towards next‐generation stable anodes are provided. [ABSTRACT FROM AUTHOR]

The critical challenge for the user acceptance of electric vehicles is the simultaneous improvement of the driving range and fast charging capabilities, which are related to the energy and power density of the storage device. Lithium‐ion batteries (LIBs) are currently the most promising candidate to push electric vehicles toward the mass market. However, they suffer from a tradeoff between energy and power density, forbidding arbitrary combinations of high storage capacity and fast charging capability. Herein, a simple electrochemical principle describing the intrinsic limits of LIBs is reported. It is deduced that the tradeoff between energy and power density originates from diffusion limitations in the electrolyte. The electrochemical approach of diffusion‐limited current density is adapted to porous Li‐ion insertion electrodes, resulting in the "diffusion‐limited C‐rate" (DLC). The theoretical considerations are in excellent agreement with experimentally observed rate limitations of a large number of electrodes with different active materials and varying design parameters. While the C‐rate drawn from an LIB cannot be higher than the DLC without significant capacity decline, parameter variations that improve the DLC reduce the nominal specific capacity. This relationship makes the DLC a fundamental quantity revealing the most expedient optimization approaches and promising directions for future battery research and development. [ABSTRACT FROM AUTHOR]