Dipl.-Ing. Hannes Weinmann

Areas of Research and Work:

  • Trend research of cell formats and production techniques in the field of electric mobility
  • Analysis of technologies and core competencies for battery cell production
  • Further and new development of concepts for machines and handling for battery cell production
  • Automation of stack forming
  • Creation of process-oriented cost models for industrial battery cell manufacturing


General Tasks:

  • Coordination of student project lecture: Production science for electriy mobility




Test Benches:

Curriculum Vitae:

Since 2016 Research Associate at the Institute of Production Science (wbk) at Karlsruhe Institute of Technology (KIT)
2014 - 2017 Study of Industrial Engineering and Management (M.Sc.) at Karlsruhe Institute of Technology (KIT)
2014 - 2015 Study of Information Systems (M.Sc.), Linnaeus University, Växjö, Sweden
2010 - 2014 Study of Industrial Engineering and Management (B.Sc.) at Karlsruhe Institute of Technology (KIT)



Leitold, L.; Spohrer, A.; Weinmann, H. W. & Fleischer, J. (2016), „Development of ball screw analysis software using MATLAB Simulink“. GAMAX Proceedings, Hrsg. Gamax Laboratory Solutions Ltd., S. 1.
In this report monitoring systems for the feed axes in machine tools, developed in MATLAB Simulink at the wbk Institute of Production Science (KIT, Germany), are presented. Implemented use cases at the wbk are the condition monitoring of ball screw drives, which can be used for the analysis of the feed axes‘ wear-status, and innovative approaches for adaptive lubrication, which can be used for the active prevention of wear as well as for preventive maintenance.

Weinmann, H.; Lang, F.; Hofmann, J. & Fleischer, J. (2018), „Bahnzugkraftregelung in der Batteriezellfertigung“, wt Werkstattstechnik online, S. 519-524.
Viele Maschinen- und Materialparameter sind für die Qualität eines Elektroden-Einzelblattes verantwortlich. Relevant für Vereinzelung und Stapelbildung ist etwa die Bahnzugkraft, mit der die Elektrodenbahn während des Stanzvorgangs beaufschlagt wird. Diese wurde in der Versuchsanlage des wbk Institut für Produktionstechnik regelbar ausgeführt, um Zusammenhänge bei der Einzelblattstapelbildung zu untersuchen. Dieser Artikel stellt Auswahl und Funktion sowie die Integration der Lösung in die Versuchsanlage und die Auswirkung verschiedener Bahnzugkräfte auf die Maßhaltigkeit der gestanzten Einzelblätter vor.

Preu, R.; Rein, S.; Zimmer, M.; Weinmann, H. W.; Hofmann, J. & Fleischer, J. (2018), „Digitalisierung bei der Produktion von Solar- und Batteriezellen“. Die Energiewende – smart und digital, Hrsg. FVEE ForschungsVerbund Erneuerbare Energien, S. 0-0.

Bold, B.; Weinmann, H. W. & Fleischer, J. (2018), „Challenges in conveying electrodes and new approaches to quality assurance“. Tagungsband zur International Battery Production Conference 2018, Hrsg. Prof. Arno Kwade, B. L. B., S. 56-57.
Electric mobility is gaining importance in Germany but high battery costs are still an obstacle. The production of battery cells amounts to a considerable share to the total costs and therefore efficiency must be further increased. Within the battery cell production the electrode is processed continuously as an electrode web until stack formation. In the individual process steps the material is guided via deflection rollers, including various compensation systems, which are designed to eliminate unevenness in the web tension and to align the position of the web edge. Such systems are mostly adapted from the paper or film processing industry. However, compared to paper or foil the electrode consists of a composite material consisting of active material and current collector. As a result, the electrode forms a system of complex properties since it consists of two materials with different mechanical properties. The presentation thus gives an overview over available market solutions and sets out why an adaptation is not possible without further ado. It also presents the challenges that occur within the material transport of electrodes. These include the wrap angle, roller diameter and web tension applied. With regard to the material parameters, the distortion of the electrode and the formation of folds are described. Up to now, the electrode behavior has been evaluated qualitatively as there are no measurement methods available. New approaches for optical methods are presented that enable a quantification of the electrode distortion within the electrode web. Three variants are described which show first promising results. By means of image processing and applied colored points their displacement is detected and thus how the electrode deforms in the process. Furthermore, another similar method is presented which works with a sprayed-on pattern and a software from the GOM GmbH for evaluation. Since these methods do not allow for an in-line quality evaluation a further variant is being considered in which the deformation of a laser pattern projected onto an electrode is assessed. Finally, a description of the material flexibility with respect to the measurement methods is given, as this will play an important role in the future.

Weinmann, H. W. & Fleischer, J. (2018), „Highly integrated machine module for single sheet stacking“. Tagungsband zur International Battery Production Conference (IBPC) 2018, Hrsg. Prof. Arno Kwade, B. L. B., S. 58.
The number of electrified vehicles and portable electronic devices announced by manufacturers is rising continuously. This inevitably leads to an increase in demand for battery cells, whereby the pouch cell is particularly well suited for some applications since it offers for example the advantage of higher format flexibility, due to the cell assembly from individual sheets, and the possibility to process thick-film electrodes. The breakthrough of the pouch cell format is currently counteracted by the comparatively high production costs which are largely attributable to the time consuming process steps of separation and assembly. The general challenges in the production for pouch cells lie in the fast and damage-free separation and positioning of the individual sheets (anode, cathode, separator) relative to each other. Thick-film electrodes and increasingly thin separators place additional demands on the production process. Thick-film and heavily calendered electrodes for example exhibit higher rigidity, resulting in new challenges for material guidance, handling and separation. According to the state of the art, electrodes and separators are often cut using lasers. This procedure favors the formation of particles which are difficult to remove from clean and dry rooms. After assembly, the individual sheets are oftentimes temporarily stored in magazines, whereby tolerances in the magazines lead to degrees of freedom and finally to a loss of the previously defined orientation and position. The contact between the magazine guide and the single sheet can also cause damage to the material, especially on the edges, just like those additional process steps for realignment and positioning of the single sheets on the cell stack. The aim of the presentation is to present a systematic derivation of a new and efficient process for forming single sheet stacks considering process related requirements. In particular, feeding and alignment of the material web as well as the separation and positioning of the individual sheets on the cell stack will be addressed. The new process is to be implemented in a highly integrated machine module that incorporates the functions of separating, conveying and depositing for electrodes or separators and thus enables a significantly reduced number of process steps. Furthermore, magazines and subsequent alignment of the electrode or separator sheets prior to cell stacking can be dispensed with. The new module should also be explicitly suitable for processing thick-film electrodes and allow a variation of the individual sheet size in one dimension. The higher format flexibility and efficiency achieved by the new process should help to further strengthen the application fields of pouch cells and at the same time reduce production costs.

Singer, R.; Weinmann, H. W.; Fleischer, J.; Smith, A. & Wiegand, O. (2018), „Function validation of an alternative and format flexible pouch cell packaging“. Tagungsband zur International Battery Production Conference (IBPC) 2018, Hrsg. Prof. Arno Kwade, S. 21.
Due to their outstanding technical properties, lithium-ion pouch cells are used as energy storage devices in electric vehicles. According to the current state of the art, these are manufactured primarily in rectangular footprints and electrically connected in cuboid battery modules to form a battery system. This has the disadvantage that the limited installation space in electric vehicles and portable devices cannot be used ideally, especially for vehicles manufactured according to the conversion design. A forward-looking research approach is therefore to produce the pouch cells in different geometries so that the installation space can be used in the tightest possible packaging. A challenge at this point is the housing of the pouch cells, which consists of a thin aluminum composite foil. Deep-drawing, the state of the art process used to produce this packaging for pouch cells, is only partially suitable for the production of format-flexible packaging that fits close to the contour of the electrode stack. For this reason, the wbk Institute of Production Science has already developed an alternative packaging design (folded pouch packaging) that meets the requirements for format-flexible pouch cells. However, the functionality of the folded pouch packaging pouch packaging could not yet be finally confirmed on a real pouch cell. This will be presented within this poster. In the first step, a geometric cell format is defined to validate the folded pouch packaging. A geometry is chosen that does not make the realization of the pouch packaging too complex. Due to the demand for gas tightness, complex folding templates for the folded pouch packaging may be necessary. The electrode stacks are stacked in a dry room atmosphere from common electrode and separator materials from individual sheets. The arresters are mounted on these sheets and, after integration of the electrode stack, nearly all sides of the packaging are closed. At least, one side of the packaging remains open so that electrolyte can be filled into the cell. Then the final sealing takes place, followed by the formation of the cell. During this process, gases are formed which must be removed from the gas pocket of the folded pouch packaging after formation. This is followed by the aging process. The data generated in this way can be used to validate the functionality of the alternative pouch cell packaging.

Bold, B.; Weinmann, H.; Bernecker, J. & Fleischer, J. (2019), „Identifying the Impact of Calendering on Subsequent Processes Using a New Approach to Quality Assurance“. Advanced Battery Power 2019, Hrsg. Haus der Technik e.v., S. 1.
Electric mobility is of core importance for the German automotive industry. The development of the German economy strongly depends on activities in battery production and on their integration into the process chain - from material to final battery system. On the one hand, further development of the material systems is necessary and on the other hand, progress is needed in production. Both aspects influence the energy density of the battery cell and thus determine the range of electrically driven vehicles or the available capacity for stationary applications. The aim of a high energy density can be achieved by finding the ideal material composition or by using the right manufacturing process. The decisive process step is calendering, in which the volumetric energy density is increased by compressing the active material. Residual stresses are induced into the material, which become visible at high densities through wrinkling at the boundary between the coated and uncoated areas. The characteristics of the wrinkles allow a conclusion to be drawn about the strength of the residual stresses. These effects in the electrode constitute a hindrance for further process steps and thus prevents the maximum possible density. In the single sheet stacking process, this is expressed through the tolerance of dimensional accuracy. Due to excessive residual stresses, the shape can no longer be guaranteed after cutting. First, the poster presents results that show which deviation is to be expected at what calendering degrees. Investigations into the cause of wrinkle formation are to be carried out by detecting the residual stresses induced. The residual stresses are determined by recording the distortions of the material. For this purpose, a pattern is printed on the electrode before calendering. A picture is taken before and after calendering, allowing the strain of the electrode to be known through the displacement of the color points. Therefore, results are presented which show the material behavior for different parameter settings at the calender for high volumetric densities. The described undertaking reveals which calender parameter is responsible for the wrinkle development. This in-line quality assurance forms the basis for modelling the relationships between the calender parameters and the properties of the material in particular residual stresses. In addition, it is the starting point for an additional module on the calender, which enables wrinkle-minimized processing of current and future material systems allowing for better qualities also in further process steps, as exemplified by the stacking process.

Diehm, R.; Weinmann, H. W.; Kumberg, J.; Schmitt, M.; Fleischer, J.; Scharfer, P. & Schabel, W. (2019), „Edge Formation in High-Speed Intermittent Slot-Die Coating of Disruptively Stacked Thick Battery Electrodes“, Energy Technology, S. 1-8. 10.1002/ente.201900137
In industrial lithium‐ion battery manufacturing, patterned structured electrodes are required due to subsequent processes. In particular, novel and advanced cell stack formation processes cause challenging design requirements for electrode geometry. This work examines the influence of coating speeds up to 50 m min–1 and wet‐film thicknesses up to 400 µm on the coating edge quality. To determine the coating edge quality, the start‐up length in every pattern in the coating direction is compared for different coating parameters. Parameters such as speed and film thickness show no limiting effect, which makes high process speeds possible.

Hofmann, J.; Halwas, M.; Weinmann, H.; Wößner, W.; Schäfer, J.; Hausmann, L.; Wirth, F.; Storz, T. & Schild, L. (2019), „Transformationshub Elektromobilität in Baden-Württemberg“ in Auf dem Weg zur Elektromobilität – Wettbewerbsfaktor Produktionstechnik , Hrsg. Fleischer, J.; Lanza, G.; Schulze, V. & , ., Shaker, Berlin, S. 1-29. ISBN/ISSN: 978-3-8440-6953-2
Die Automobilindustrie steckt in einem Transformationsprozess un-geahnten Ausmaßes und Ausgangs. Ob durch striktere europäische Abgasgrenzwerte, den Zwang lokaler Emissionsfreiheit oder den Druck des chinesischen Marktes beim Kampf um eine neue Vorherrschaftsrolle - die Gründe deutscher Automobilisten zur Elektrifizierung sind vielschichtig und die Folgen kaum abschätzbar. Die Frage, ob neue Antriebstechnologien in den Markt eingeführt wer-den, stellt sich mittlerweile kein Automobilhersteller mehr, stattdessen verbleibt die Frage nach dem „wie“. Mit der diesjährigen wbk Herbsttagung „Auf dem Weg zur Elektromobilität – Wettbewerbsfaktor Produktionstechnik“ wollen wir die vorhandenen Chancen im Bereich der Produktionstechnik für die Elektromobilität aufzeigen und einen Beitrag dazu leisten, dass diese auch genutzt werden. Hochkarätige Impulsvorträge aus Industrie und Forschung schaffen die Diskussionsbasis für einen Informationsaustausch zur Elektromobilität. Die wbk-Herbsttagung bietet dabei eine Plattform für den Dialog zwischen Politik, Anwendern, Produzenten, Anlagenbauern sowie dem wbk als Forschungspartner vor Ort.

Weinmann, H. W. & Fleischer, J. (2019), „Influences of Increasind Coating Thicknesses and Calendering Degrees on Single-Sheet-Stack Formation“. International Battery Production Conference IBPC, Hrsg. Technische Universität Braunschweig, S. 49.
Due to increasing energy and power densities, new fields of application for lithium-ion battery cell technology are constantly emerging. However, the energy and power densities that can be achieved on a laboratory scale are often limited by the industrially available production equipment. The growing demand, especially for high-energy cells, also reveals a deficit in production technology. The systems currently available on the market are often unable to process corresponding materials, which increasingly poses challenges for cell manufacturers. Unfortunately, many products that can be manufactured on a laboratory scale currently fail due to their manufacturability on an industrial scale. Within the HighEnergy project, the wbk - Institute of Production Science has dealt with the processability of thick-film electrodes and is also conducting research with respect to the influence of increasing degrees of calendering on the subsequent process steps, especially with regard to the formation of single sheet stacks. The aim of this presentation is therefore to give an overview on influences of increasing coating thicknesses and calendering degrees on the stacking process and to demonstrate various process interactions. In particular, the material guidance and alignment, the separation and the positioning of the individual sheets on a cell stack will be examined more closely. Different requirements which the materials place on the production process will also be examined, e.g. how different web tensions depending on the calendaring degree lead to different levels of dimensional accuracy in single sheet cutting. Finally, it will be shown how these versatile findings can be integrated and how they lead to a process model. This model forms the basis for a statement about the processability of novel or changing materials.

Weinmann, H. W.; Töpper, H. & Fleischer, J. (2020), „Coil2Stack: Ein innovatives Verfahren zur formatflexiblen Batteriezellherstellung“, ZWF Zeitschrift für wirtschaftlichen Fabrikbetrieb, Band 115, Nr. 4, S. 241-243. 10.3139/104.112192
Die wirtschaftliche Herstellung von Lithium-Ionen-Batteriezellen in verschiedenen Formaten und aus unterschiedlichen Materialien fordert flexible Anlagen für die Stapelbildung. Im Rahmen dieses Beitrags werden deren Prozesse, aktuell verfügbare Lösungen sowie Trends in der Materialentwicklung analysiert, um ein neuartiges Anlagenkonzept abzuleiten, welches den Forderungen nach Flexibilität bezüglich Zellformat und Material gerecht wird und bisher bestehende Defizite ausgleicht.

Weinmann, H. W.; Eichelkraut, M.; Woke da Silva, L. & Fleischer, J. (2020), „Batteriezellenfertigung vom Coil zum Stack: Integriert, automatisiert und dadurch hoch flexibel“, Coating & Concerting, Band 4, S. 21-24. [30.11.-1].
Mit bekannten Stapelverfahren ist wirtschaftliche Produktion verschiedener Batteriezellformate aus unterschiedlichen Materialien in kleinen bis mittleren Losgrößen selten möglich. Ein neuer Ansatz integriert bislang diskrete Fertigungsschritte zu einem kontinuierlichen, vollautomatisierten, dadurch sehr material- und formatflexiblen Stapelprozess. Performante Steuerungs- und Antriebstechnik von Siemens macht das Coil2Stack-Verfahren präzise regelbar, einfach portierbar und zukunftssicher.

Schäfer, J.; Weinmann, H. W.; Mayer, D.; Storz, T. & Hofmann, J. (2020), „Synergien zwischen Batterie- und Brennstoffzelle“, S. 735-741. [30.11.-1].
Nach Ankündigung diverser batterieelektrischer Modelle wird auch die PEM (Proton Exchange Membrane)-Brennstoffzelle als mögliche Zukunftstechnologie im Last- und Linienverkehr diskutiert. Ob und wann sich eine Technologie durchsetzt, hängt von der verwendeten Produktionstechnik ab, denn diese bestimmt Stückzahlen und resultierende Kosten. Die Vergangenheit zeigt, dass sich produzierende Industrien oft entlang vorhandener Kompetenzen in etablierten Bereichen entwickelt haben. In diesem Beitrag sollen daher Synergiepotenziale zwischen der Batterie- und Brennstoffzellenfertigung diskutiert werden.