This roadmap presents the transformational research ideas proposed by “BATTERY 2030+,” the European large‐scale research initiative for future battery chemistries. A “chemistry‐neutral” roadmap to advance battery research, particularly at low technology readiness levels, is outlined, with a time horizon of more than ten years. The roadmap is centered around six themes: 1) accelerated materials discovery platform, 2) battery interface genome, with the integration of smart functionalities such as 3) sensing and 4) self‐healing processes. Beyond chemistry related aspects also include crosscutting research regarding 5) manufacturability and 6) recyclability. This roadmap should be seen as an enabling complement to the global battery roadmaps which focus on expected ultrahigh battery performance, especially for the future of transport. Batteries are used in many applications and are considered to be one technology necessary to reach the climate goals. Currently the market is dominated by lithium‐ion batteries, which perform well, but despite new generations coming in the near future, they will soon approach their performance limits. Without major breakthroughs, battery performance and production requirements will not be sufficient to enable the building of a climate‐neutral society. Through this “chemistry neutral” approach a generic toolbox transforming the way batteries are developed, designed and manufactured, will be created.

The development of new batteries has historically been achieved through discovery and development cycles based on the intuition of the researcher, followed by experimental trial and error—often helped along by serendipitous breakthroughs. Meanwhile, it is evident that new strategies are needed to master the ever‐growing complexity in the development of battery systems, and to fast‐track the transfer of findings from the laboratory into commercially viable products. This review gives an overview over the future needs and the current state‐of‐the art of five research pillars of the European Large‐Scale Research Initiative BATTERY 2030+, namely 1) Battery Interface Genome in combination with a Materials Acceleration Platform (BIG‐MAP), progress toward the development of 2) self‐healing battery materials, and methods for operando, 3) sensing to monitor battery health. These subjects are complemented by an overview over current and up‐coming strategies to optimize 4) manufacturability of batteries and efforts toward development of a circular battery economy through implementation of 5) recyclability aspects in the design of the battery.

Avoiding harmful passivation of the lithium metal surface during its implementation as an anode material is a challenge to its use in rechargeable lithium metal batteries. It is critical to control the chemical composition and the morphology of the native passivation layer and to avoid contamination by lubricants or other substances involved in the processing. Herein, abrasive blasting is used as a physical method to achieve clean and 3D‐structured lithium metal electrodes. The careful choice of the abrasive agent and the blasting parameters results in well‐controlled surface properties. The blasted lithium electrodes exhibit significantly lower overvoltages with values as low as 10 mV at 0.1 mA cm−2. Electrochemical impedance spectroscopy shows that blasted lithium has interface resistances that are up to five times smaller than those of untreated lithium. The effectiveness of blasting as a cleaning method is clear even in the case of thicker and highly resistive passivation layers occurring after exposure to ambient air.

Open access to research data is increasingly important for accelerating research. Grant authorities therefore request detailed plans for how data is managed in the projects they finance. We have recently developed such a plan for the EU-H2020 BIG-MAP project - a cross-disciplinary project targeting disruptive battery-material discoveries. Essential for reaching the goal is extensive sharing of research data across scales, disciplines and stakeholders, not limited to BIG-MAP and the European BATTERY 2030+ initiative but within the entire battery community. The key challenges faced in developing the data management plan for such a large and complex project were to generate an overview of the enormous amount of data that will be produced, to build an understanding of the data flow within the project and to agree on a roadmap for making all data FAIR. This paper describes the process we followed and how we structured the plan.

This work shows, for the first time, the critical influence of pressure during the hot sintering stage on the ionic conductivity of the lithium super ionic conductor Li 1.5 Al 0.5 Ge 1.5 (PO 4 ) 3 . A hot press method is developed to obtain high ionic conductivities at the significantly decreased densification temperature of only 650 °C by applying pressure (56 MPa). Considering the possible initiation of undesirable decomposition reactions when cathode materials are annealed at high temperature (typically ≥700 °C), the use of high pressure at 650 °C can significantly limit the formation of degradation by‐products. This study determines the criteria required to optimize the pressure and temperature parameters for enhancing the total ionic conductivity. Finally, this study reports an all solid‐state battery based on a LiFePO 4 olivine cathode prepared at 650 °C showing very good Li‐intercalation/deintercalation performance. Good ionic interfacial contact is achieved without using polymer and liquid electrolyte.

In article number 2000164, Andrea Paolella, Karim Zaghib, and co-workers describe a new hot press method to densify NASICON Li1.5Al0.5Ge1.5(PO4)3 (LAGP) with high ionic conductivities at only 650 °C by applying pressure (56 MPa). The cover shows the possible applications of an all solid-state battery based on a LiFePO4 olivine cathode, LAGP electrolyte and lithium metal.

Dendrite formation, which could cause a battery short circuit, occurs in batteries that contain lithium metal anodes. In order to suppress dendrite growth, the use of electrolytes with a high shear modulus is suggested as an ionic conductive separator in batteries. One promising candidate for this application is Li 7 La 3 Zr 2 O 12 (LLZO) because it has excellent mechanical properties and chemical stability. In this work, in situ scanning electron microscopy (SEM) technique was employed to monitor the interface behavior between lithium metal and LLZO electrolyte during cycling with pressure. Using the obtained SEM images, videos were created that show the inhomogeneous dissolution and deposition of lithium, which induce dendrite growth. The energy dispersive spectroscopy analyses of dendrites indicate the presence of Li, C, and O elements. Moreover, the cross-section mapping comparison of the LLZO shows the inhomogeneous distribution of La, Zr, and C after cycling that was caused by lithium loss near the Li electrode and possible side reactions. This work demonstrates the morphological and chemical evolution that occurs during cycling in a symmetrical Li–Li cell that contains LLZO. Although the superior mechanical properties of LLZO make it an excellent electrolyte candidate for batteries, the further improvement of the electrochemical stabilization of the garnet–lithium metal interface is suggested.

Garnet-type lithium lanthanum zirconate (Li7La3Zr2O12, LLZO)-based ceramic electrolyte has potential for further development of all-solid-state energy storage technologies including Li metal batteries as well as Li-S and Li-O-2 chemistries. The essential prerequisites such as LLZO's compactness, stability, and ionic conductivity for this development are nearly achievable via the solid-state reaction route (SSR) at high temperatures, but it involves a trade-off between LLZO's caveats because of Li loss via volatilization. For example, SSR between lithium carbonate, lanthanum oxide, and zirconium oxide is typically supplemented by dopants (e.g., gallium or aluminum) to yield the stabilized cubic phase (c-LLZO) that is characterized by ionic conductivity an order of magnitude higher than the other polymorphs of LLZO. While the addition of dopants as phase stabilizing agent and supplying extra Li precursor for compensating Li loss at high temperatures become common practice in the solid-state process of LLZO, the exact role of dopants and stabilization pathway is still poorly understood, which leads to several manufacturing issues. By following LLZO's chemical phase evolution in relation to Li loss at high temperatures, we here show that stabilized c-LLZO can directly be achieved by an in situ control of lithium loss during SSR and without needing dopants. In light of this, we demonstrate that dopants in the conventional SSR route also play a similar role, i.e., making more accessible Li to the formation and phase stabilization of c-LLZO, as revealed by our in situ X-ray diffraction analysis. Further microscopic (STEM, EDXS, and EELS) analysis of the samples obtained under various SSR conditions provides insights into LLZO phase behavior. Our study can contribute to the development of more reliable solid-state manufacturing routes to Garnet-type ceramic electrolytes in preferred polymorphs exhibiting high ionic conductivity and stability for all-solid-state energy storage.

Abstract A nanolayer of reactive propyl acrylate silane groups was deposited on a lithium surface by using a simple dipping method. The polymerization of cross‐linkable silane groups with a layer of ally‐ether‐ramified polyethylene oxide was induced by UV light. SEM analysis revealed a good dispersion of silane groups grafted on the lithium surface and a layer of polymer of about 4 μm was obtained after casting and reticulation. The electrochemical performance for the unmodified and modified lithium electrodes were compared in symmetrical Li/LLZO/Li cells. Stable plating/stripping and low interfacial resistance were obtained when the modified lithium was utilized, indicating that the combination of silane and polymer deposition is promising to increase Li‐metal/garnet contact.

Fast charging of Li-ion cells is one of the main challenges in automotive battery applications. As a particular problem at low temperatures and high charging rates, lithium deposits as metal on the anode surface instead of intercalation. Capacity loss resulting from lithium plating is the main aging effect at low temperatures [1][2]. Moreover, the deposited Li can form dendritic deposits which are known to trigger internal short circuits when piercing through the battery separator [3]. In this work a micro-scale model [4] [5] was used to investigate the onset of lithium plating during charging at low temperatures in commercial lithium-ion batteries. The model was parameterized and validated with materials from NMC-Graphite commercial cells. The cells were opened in a glovebox with controlled argon atmosphere and the transport properties of the electrode materials at different temperatures were measured by Potentiostatic Intermittent Titration (PITT) and Galvanostatic Intermittent Titration Technique (GITT). The mean particle size, thickness and porosities were determined by SEM microscopy (Figure 1a). The model predictions of the onset temperature for lithium deposition on graphite electrodes were validated through experimental measurements on laboratory full cells. The reversible plating can be identified by the Li stripping plateau during discharge. Figure 2 shows the onset temperature (-10 °C) of lithium plating during CCCV charge at 1C. Irreversible plating on the graphite electrode was measured by inductively coupled plasma optical emission spectroscopy (ICP-OES). The developed model is used to establish suitable operating conditions that avoid lithium plating in Li-ion batteries while maximizing charge rates and minimizing heating requirements. [1] V. Zinth, C. von Lüders, M. Hofmann, J. Hattendorff, I. Buchberger, S. Erhard, J. Rebelo-Kornmeier, A. Jossen, R. Gilles, J. Power Sources 271 (2014) 152–159. [2] C. Uhlmann, J. Illig, M. Ender, R. Schuster, E. Ivers-Tiffee, J. Power Sources 279 (2015) 428-438. [3] Z. Li, J. Huang, B. Yann Liaw, V. Metzler, J. Zhang, J. Power Sources 254 (2013) 168-182. [4] A. Latz, J. Zausch, J. Power Sources 196 (2011) 3296–3302. [5] G. B. Less, J. H. Seo, S. Han, A. M. Sastry, J. Zausch, A. Latz, S. Schmidt, C. Wieser, D. Kehrwald, S. Fell, J. Electrochem. Soc 159 (2012) A697-A704 Figure 1

Second-life applications of automotive lithium-ion batteries are currently investigated for grid stabilization. Reutilization depends on reliable projections of the remaining useful life. However, reports on sudden degradation of lithium-ion-cells near 80% state of health challenge these extrapolations. Sudden degradation was demonstrated for different positive active materials. This work elucidates the cause of sudden degradation in detail. As part of a larger study on nonlinear degradation, in-depth analyses of cells with different residual capacities are performed. Sudden degradation of capacity is found to be triggered by the appearance of lithium plating confined to small characteristic areas, generated by heterogeneous compression. The resulting lithium loss rapidly alters the balancing of the electrodes, thus generating a self-amplifying circle of active material and lithium loss. Changes in impedance and open-circuit voltage are explained by the expansion of degraded patches. Destructive analysis reveals that sudden degradation is caused by the graphite electrode while the positive electrode is found unchanged except for delithiation caused by side reactions on the negative electrode. Our findings illustrate the importance of homogeneous compression of the electrode assembly and carbon electrode formulation. Finally, a quick test to evaluate the vulnerability of cell designs toward sudden degradation is proposed. (C) 2016 The Authors. Published by Elsevier Ltd.

The thermomechanical and transport properties of a series of hybrid polymer electrolytes are examined by means of differential scanning calorimetry, rheological analysis and broadband electric spectroscopy. The electrolytes are composed of 3D-oligosiloxane defect clusters grafted with polyether chains and doped with LiClO4, with concentration ranging from 0 to 1.4 mol.kg(-1). The thermomechanical properties are mainly modulated by the balance of interactions taking place within the polyether domains. The materials show low T-g and no crystallization in a wide salt concentration range, while the mechanical modulus, between 10(4) and 10(5) Pa, is stable up to at least 100 degrees C. A detailed electric characterization, combined with the results from vibrational spectroscopy analysis, elucidates the factors influencing the transport properties. The conductivity reaches 8 x 10(-5) S.cm(-1) at 30 degrees C for intermediate salt concentrations. The sluggishness of the host matrix appears to be the limiting factor depressing the conductivity at higher salt concentrations. Conversely, the appearance of ion aggregates plays a negligible role, at least in the concentration range examined.

All-solid-state batteries have been shown as an innovative candidate for next-gen lithium-ion batteries. Thin-film technologies offer an approach to solve several inherent challenges. To achieve a complete thin-film all-solid-state battery all components, especially electrodes and solid electrolytes have to be prepared in a suitable combination. In contrast to conventional liquid-solid electrolyte-electrode systems, additional requirements arise from the fact that electrochemically active interfaces have to be formed while preparing. Using cost efficient and upscalable sol-gel processes solid NASICON-type electrolytes (e. g. Li1+xAlxTi2-x(PO4)3, LATP) offer a high ionic conductivity at room temperature and a high anodic stability [1]. In previous work we presented a LATP solid electrolyte prepared by sol-gel methods on a current collector as substrate [2]. In a layer-by-layer setup (shown in Fig. 1) the substrate-anode system forms the underlying substrate for the electrolyte coating. Oxide-based electrodes indicate interfacial reactions in the presence of NASICON-type electrolytes at temperatures higher than 300 °C [3]. Therefore they turned out to be unstable in the coating-associated temperature treatment. Phosphate-based electrode materials provide a suitable approach. This poster presents single- and multi-layer films a of phosphate-based anode material on conducting transparent oxides prepared by dip- and spin- coating method. The single- and multi-layer systems exhibited good electrochemical properties and appear suitable for the electrolyte coating process including the associated temperature treatment. Grazing incidence X-ray diffraction reveals no interface reaction and SEM investigation shows a good physical connection on the electrolyte-electrode interface. Furthermore, half-cell CV and cycling tests confirm a low charge transfer resistance at the interface. Future work will focus on the cathode/electrolyte interface and finally a working solid-state cell. [1] P. Knauth, Solid State Ionics 2009, 180, 911–916. [2] F. Frech et. al., Development of thin glass-ceramic electrolytes via a sol-gel route, Poster on IMLB 2014 [3] A. Aboulaich et. al., Adv. Energy Mater. 2011, 1, 179–183 Figure 1

One of the major challenges of metal-air batteries is the impeded oxygen reduction reaction (ORR) during discharge occurring at the gas diffusion electrode (GDE) of the battery. Due to the impeded ORR, high overpotentials emerge and result in a loss of energy efficiency. In order to improve the latter, suitable catalysts have to be employed. Transition metal oxides like manganese oxides (e.g., MnO2, Mn2O3, Mn3O4, Mn5O8, MnOOH) [1,2] are known as good and inexpensive materials for the ORR in alkaline media. A drawback of manganese oxide catalysts is the poor electrical conductivity. Hence, the approach presented in this work aims to enhance the catalytic activity of Mn3O4 and γ–MnO2 by the incorporation of conductive carbon material into the pure manganese oxide. The resulting hybrid catalysts are prepared either by impregnation of Super C 65, Vulcan XC 72, and Kuraray YP 50F via a sol-gel technique employing a MnO2 precursor sol or by direct precipitation of Mn3O4 or γ–MnO2 particles in the presence of the carbon materials mentioned above. Investigations by rotating disc electrode (RDE) show a noticeably higher catalytic activity of the hybrid catalysts than for the pure materials. For verification of the results measured by RDE, screen printed GDEs are prepared and tested in Zn-air full cells.

Establishing thin-film technologies for lithium ion batteries is an important step towards all-solid-state batteries. Solid thin-film electrodes expose significantly higher charge and discharge rates than standard composite electrodes, thus have the potential to increase the power density of thin-film batteries. Sol-gel procedures are established in battery research for synthesizing active material powders with controlled particle sizes. Here, we prepared single- and multi-layer films of active materials viadip-coating method. Both electrode single-layer systems exhibit excellent electrochemical properties such as high reversibility and low polarization in long-term CV measurements and show almost full capacity retention at charge and discharge currents up to 100 C. Furthermore, applied on transparent conducting oxides, the electrodes were of high optical quality and showed intense color changes upon charging and discharging which positions them as interesting electrochromic compounds. Both materials are well known for their high reversibility and low cost compared to commonly known electrochromic metal oxides such as tungsten oxide. The combination of their highly stable and very fast cycling capabilities with their color switching properties, make the presented transparent thin film electrodes promising candidates for high-power all-solid-state and electrochromic applications. This paper shows transparent Li4Ti5O12 and LiMn2O4 thin film electrodes characterized by the above mentioned electrochemical measurements and their optical properties with the help of UV-vis spectroscopy. Additionally, material characterization is demonstrated via X-ray diffraction, XPS and SEM imaging. Figure 1