Influence of conductivity additives and their distribution on the performance properties of lithium-ion batteries
A lithium ion battery (LIB) cathode comprises three major components: an active material, an electrical conductivity additive and a binder. The composite combination of binder and electrical conductivity additive, the carbon binder domain (CBD) is electrochemically inert. Preparation of a LIB cathode strongly influences the dispersion of the above-mentioned constituents leading to the formation of […]
Development of Representative Microstructure Model to Investigate the Electro-chemo-mechanical Response of Lithium-Ion Batteries
Due to the increasing market share of Battery Electric vehicles (BEVs), the importance of electrochemical energy storage systems is continuously increasing. Due to their high energy density, Lithium-Ion Batteries (LIBs) are currently the most important energy storage system for BEVs. The electrode microstructure in LIBs has a substantial impact on their electrochemical performance. Therefore, optimization […]
Development of Representative Microstructure Model to Investigate the Electro-chemo-mechanical Response of Lithium-Ion Batteries
Due to the increasing market share of Battery Electric vehicles (BEVs), the importance of electrochemical energy storage systems is continuously increasing. Due to their high energy density, Lithium-Ion Batteries (LIBs) are currently the most important energy storage system for BEVs. The electrode microstructure in LIBs has a substantial impact on their electrochemical performance. Therefore, optimization […]
On the contribution of the anode to the cyclic ageing behaviour of NCM622//Graphite full cells – a physicochemical post-mortem analysis combined with operando X-ray diffraction
Concerning cell ageing and lithium-plating, electrode kinetics – in particular the one of the anode – plays an important role. During cyclic ageing both electrodes are subject to microstructural and chemical changes that might have a negative influence on the electrode kinetics, such as layer formation, transition metal dissolution and subsequent deposition and pore clogging. […]
Battery calorimetry to enhance lifetime and safety of LIB
With increasing energy density the safety and the thermal management of Li-ion batteries is becoming more and more important, because the thermal runaway can cause an ignition or even explosion of the battery with simultaneous release of toxic gases. In the last nine years we have established battery calorimetry as a powerful and versatile electrochemical-thermal […]
Predicting Electrolyte Performance by PCDC Measurements
The approach presented here, addresses the general problem to determine properties of binary liquid electrolytes by a simple, reliable and fast measurement. In particular, we focus on the determination of the binary salt diffusion coefficient. Alternative methods applied so far require long measurements or complex and expensive measurement equipment. For instance, Pulsed-Field-Gradient NMR measurements lead […]
Impact of cyclic and calendar aging on the degradation and thermal behavior of cylindrical lithium ion cells
Lithium-ion batteries (LIB) are experiencing a significantly increasing demand for consumer goods, as well as for battery electric and hybrid electric vehicles. The broad usage possibilities of medium sized cylindrical cells, e.g. of size 18650 and 21700, results in multifaceted requirements and usage conditions. In consequence, the performance of these cells in everyday usage and […]
3D structured cathodes for Li-ion batteries based on Al metal foams for high energy applications
The demand for Li-ion batteries with ever increasing energy and power density is not only for automotive applications. Inter alia, high energy density and mechanical stability together with small electrode and cell dimensions are required for medical technology systems or wearable devices. Thus, increasing the areal loading of electrodes is necessary to meet the demands. […]
Microscale Simulation of Battery Aging
During cycling, volumetric changes of the active material induce stresses on the micro- and macro-scale, leading to cracks and delamination, and deformation of the inactive layers and the casing. The altered microstructure is said to “age” and suffers from capacity loss and damaging effects like lithium-plating. The quantitative simulation of this battery aging on a […]
Thickness change investigation of lithium-ion pouch cells using measurements and modeling
During cycling and aging, volume changes occur in the active materials of a lithium-ion battery cell. These volume changes lead to a formation of stresses inside the cell, which may compromise battery lifetime. Therefore, the simulation of the mechanical behavior of lithium-ion cells is an important instrument in the early stages of battery cell design. […]