Detection of inhomogeneities in serially connected lithium-ion battery packs
Serially connected battery packs present a cell-to-cell variation in their electrochemical behavior due to deviations during production, different temperature distributions or mechanical stress that tends to increase over the lifetime. This can lead to individual cells having significantly different electrical properties than the cell group, described in this work as inhomogeneity. This single outlier can […]
Challenges of next-generation battery energy storage systems with silicon anodes
Silicon is a promising next-generation active material to largely replace graphite as the anode in lithium-ion batteries. The very high specific capacity of up to 3600 mAh/g [1, 2] in combination with low potentials vs. Li/Li+ leads to cells with extraordinarily high energy density. The challenge of the commercialization of silicon as an anode material […]
Interplay of Pressure and Electrolyte on the (Ir)Reversible Expansion of State-of-the-Art and Next-Generation Battery Materials using Operando Dilatometry
In this work, the correlation between mechanical pressure on the cell and volume expansion is studied for state-of-the-art (SoA) and next generation materials for lithium-ion batteries. The effect of volume changes, primarily of the anode, on the electrochemical processes occurring within the cell is investigated using a custom-built operando dilatometry test setup. With this test […]
Inductive drying of lithium ion NMC622 cathodes
To match the steadily increasing demand of lithium-ion batteries all battery production steps have to be enhanced in terms of quality and performance. In this regard, the drying process of electrodes holds great potential for improvement. The main challenge of state-of-the-art convective drying methods is the high energy consumption within the drying step. This study […]
In-Situ Visualization of Electrode Layers in Lithium-Ion Cells with Scanning Acoustic Tomography
Imaging the interior of battery cells provides vital information for battery manufacturing, as well as lifetime and performance prediction. We demonstrate a scalable and in-situ method to image the structural state of battery cells with layer resolution. Ultrasound waves are applied on pouch cells and the reflected wave is processed to provide depth information gathered […]
Impact of the Compression Ratio due to Calendering on the Effective Thermal Conductivity of Lithium-Ion Cell Electrodes
During the design process of lithium-ion batteries the simultaneous optimization of the mechanical, electrical and thermal properties of the components and their interfaces is crucial. As these are strongly influenced by the production steps, a thorough understanding of their impact on said properties is key to reaching optimized material properties of the cells. While many […]
Impact of In Coin Cell Atmosphere on Lithium Metal Electrode Performance
Research on lithium metal as a high-capacity anode for future lithium metal batteries (LMBs) is currently at an all-time high. To date, the different influences of a highly pure argon glovebox (GB) and an industry-relevant ambient dry room (DR) atmosphere have received little attention in the scientific community. In this study, we report on the […]
Regeneration of NCM811 after separation from the decanter centrifuge
Currently, several processes exist for the recycling of lithium-ion batteries (LIBs). The pyrometallurgical approach, for example, is robust and safe, but the achievable recycling rate is limited, especially with respect to certain elements and starting compounds (or precursors). In contrast, the mechanical approach promises potentially higher recycling rates, but comes along with higher safety risks, […]