In this lecture, scalable concepts for positive and negative high energy electrodes are presented. A dry process is shown that replaces slurry-based binders by a fibrous PTFE binder and reduces the binder amount to an absolute minimum. Furthermore, we combined the solid-state technology with PVD-based, scalable silicon anode concepts developed at Fraunhofer IWS.

For solid-state batteries to become a competitive alternative to lithium-ion batteries, the internal resistance needs to approach or surpass that of lithium-ion batteries while employing lithium metal as anode material. Analysis and design of the interfaces through which lithium ions migrate is crucial in reducing interface resistance of the cells. This is particularly important at both cathode and anode interfaces, where electrochemical and mechanical degradation need to be mitigated.

Solid-state battery system poses new challenges to the battery design due to the unique solid-solid interfaces at battery cathode and anode. However, these interfaces, upon critical understanding and design, also form the new opportunity to achieve battery performances beyond the current commercial liquid electrolyte batteries. We design the lithium metal anode for solid state batteries by our unique mechanical constriction principle, making a more stable cycling at high current densities.

Next generation of energy storage devices may largely benefit from fast and solid Li+ ceramic electrolyte conductors to allow for safe and efficient batteries and fast data calculation. For those applications, the ability of Li-oxides to be processed as thin film structures and with high control over lithiation and phases at low temperature is of essence to control conductivity. 

Herein, in situ tomography is carried out to track morphological transformations in Li metal electrodes and buried solid|solid interfaces  during stripping and plating processes. Optimized experimental parameters enable high resolution, high contrast reconstructions that enable lithium metal visualization. Quantitative analysis tools (machine  learning, image processing) are developed that enable quantification of  physical descriptors of lithium metal (spatial current density, porosity, spatial distribution of pores) during cycling.

ULVAC is a comprehensive manufacturer of vacuum equipment and components. We have been developing batteries using vacuum technology for more than 15 years, and have now refined our development to two primary topics; Thin Film Batteries, and Li metal anode films. In this talk we will discuss our recent development work on these topics, and introduce ULVAC’s manufacturing technology, battery performance, and a new method of measuring the material interface.

Laser-patterning of vertical channels into post-calendared graphite anodes improves fast-charge capability by creating pathways for rapid ionic transport through the electrode thickness. This allows for a more homogeneous flux of Li and deceased concentration gradients during fast charging, which is supported by continuum-scale modeling. We demonstrate significant improvements in accessible capacity and minimal capacity fade at 4C-6C rates, in >2Ah pouch cells with >3 mAh/cm² loadings using standard roll-to-roll processing.

High-energy density cells suitable for EVs have traditionally had poor maximum charge acceptance rates. Modeling and experimental results from DOE's XCEL program show insufficient transport within the electrolyte phase is a major limitation in being able to fast charge EV suitable cells at >4C.  Various strategies to improve ion transport within the electrolyte phase will also be detailed such as modifying electrolyte formulation, elevated temperature, and reduced electrode tortuosity.

Higher energy density and voltage Li-Ion batteries are a key to future EV performance. With this, the number of components requiring dielectric protection is increasing. This presentation will review critical components, requirements, and the options for dielectric protection solutions including support for scale manufacturing and cost. 

The merge of Laser 3D Battery Concept and thick film concept enables high-energy and high-power operations at the same time while suppressing cell degradation processes at pouch cell level. For this purpose the ultrafast laser structuring was applied to energy storage materials such as ultra-thick film nickel-enriched NMC cathodes and silicon/graphite-based anodes. Upscaling of laser technology and the transfer into pilot lines is currently under development.

Born out of the laboratory, Group14 Technologies has cracked the code with a patented silicon-carbon composite to enable longer-lasting, lithium-silicon batteries that deliver a 50% increase in energy density. Group14's technology is created through a patented two-step process, which creates silicon within a flexible carbon scaffold to form a silicon-carbon composite with void space to make charging more efficient while allowing for silicon's expansion and contraction during its cycle life.

LiFePO4 (LFP) is an attractive alternative that is non-toxic, thermally stable, and durable. We demonstrate the scale-up for LiFePO4/C production via melt-casting, wet media mill and spray drying. The optimum is capacity (/C: 161 mAh g-1 at 0.1C), discharge rate (flat plateau, 145 mAh g-1 at 5C), and cyclability (91% capacity retention after 750 cycles at 1C). Particle size, carbon precursor and ultrasonication affect cathode performance.