Customcells® Contact persons

At CUSTOMCELLS®, we are happy to be personally available to our clients and partners. Our employees are always at the heart of CUSTOMCELLS®. We practice a management concept with flat hierarchies that encourage exceptional commitment and give all our employees a high degree of personal responsibility.


  Yann-Erik Ritz       Kim-Sascia Milinowski       Stefan Roschinski      Jan Majchel        Dr. Anne Baasner       Jörg Scheele

Yann-Erik Ritz

Yann-Erik already worked in the automotive industry in the area of product strategy and project management parallel to his studies (mechanical engineering, B.Sc. and product development, M.Sc.) at the TU Hamburg. After his master's thesis in the field of recycling high-voltage batteries, he started at CUSTOMCELLS®. Since mid-2021, Yann-Erik has been working at CUSTOMCELLS® as a Project Planner with a focus on automotive projects.

Kim-Sascia Milinowski

Kim-Sascia Milinowski started her professional career as a retail saleswoman. After several years of permanent employment, she sought new challenges and acquired new knowledge and skills in various companies. At times, Kim worked as an office administrator, purchasing clerk and controller in the content area. Since the beginning of 2022, Kim has been working for CUSTOMCELLS® as a sales assistant.

Stefan Roschinski

After his studies in international business administration, Stefan specialised in the areas of marketing and sales. He gained his first professional experience at the Anschutz Entertainment Group, where he was involved in the restructuring of the sales department. Subsequently, Stefan worked for Johnson & Johnson Medical for seven years in various areas and functions. Since the beginning of 2022, Stefan has been responsible for sales and project planning at CUSTOMCELLS®.

Jan Majchel

At an early stage, Jan dedicated himself to future-oriented and sustainable energy use at the University of Kassel in Environmental Engineering (B.Sc.). With his subsequent studies in energy technology (M.Sc.) at the University of Stuttgart and his final thesis on optimised catalysts for water electrolysis, he turned to electrochemistry. This was followed by almost five years of research into new battery technologies at the German Aerospace Center (DLR) in Stuttgart. Since summer 2021, Jan has been strengthening the CUSTOMCELLS® sales team as a project planner.

Dr. Anne Baasner

Anne studied chemistry at the Technical University of Dresden. After synthesizing dyes for organic solar cells in her bachelor thesis at the Dresden Institute of Applied Photophysics (IAPP), she specialized in inorganic materials for energy storage in her master studies. During her master thesis and PhD at Fraunhofer IWS Dresden in the group of Dr. Holger Althues she developed silicon-carbon anode materials and investigated different silicon-based anodes in lithium-ion batteries. Since November 2019 she is working as a project planner at CUSTOMCELLS©.

Jörg Scheele

Jörg began his professional career as an aircraft electronics engineer at Deutsche Lufthansa AG. After graduating in business informatics and business administration, Jörg held various positions such as controlling, investor relations, sales and asset manager for international listed companies. Most recently, he worked for many years as Senior Analyst for Goldman Sachs before moving to CUSTOMCELLS® as Senior Sales Manager in May 2017.


Leopold König    Mike Eisermann    Thomas Walter   Dr. Daniela Werlich   Dr. Martin Ruge    Katharina Anders    Torge Thönnessen

Leopold König

Managing director, founder and one of the visionaries of CUSTOMCELLS®. As early as 2011, Leopold positioned himself for electromobility by moving to the development department for lithium polymer cells at Fraunhofer ISIT and founding CUSTOMCELLS® Itzehoe GmbH the following year. Leopold is a specialist for application analyses and production technologies related to battery cells. Before that, he gained several years of international professional experience in the context of corporate controlling, the digitalization of factories, the construction and new construction of a pharmaceutical production facility in China and the technical support of large-scale real estate projects. The diversity of the individual projects has led to an extensive cross-industry network. He studied industrial engineering at Stralsund University, specializing in mechanical engineering and business management. Previously, Leopold König worked for several years as a paramedic in emergency situations and learned at an early age how to act proactively and lead teams under difficult conditions.

Mike Eisermann

After studying business administration, Mike immersed himself in self-employment as a business graduate. As managing director of an online agency and subsequently as head of an advertising agency, he was responsible for numerous customer projects and concepts for more than 15 years. Today he is responsible for the marketing and PR department at CUSTOMCELLS® and is your contact for advertising, public relations, social media, trade fairs and design & communication.

Thomas Walter

In the course of his professional career, Thomas has completed further training as a hr specialist and as a certified hr manager (DAM). In the last 12 years, Thomas has mainly worked in the operative and strategic personnel management of medium-sized companies. Since mid-July 2020 Thomas is working as HR Manager for CUSTOMCELLS®.

Dr. Daniela Werlich

After receiving her doctorate in chemistry in 2012, Daniela took over a position as project manager at a German cell manufacturer. Here she not only gained comprehensive insights into the process management of lithium-ion cell technology, but was also actively involved in the process during the ramp-up phase. Since 2016 Daniela has been responsible for the continuous development of our technology at CUSTOMCELLS® as CTO of the company in addition to her role as project manager. As a member of the management boards of the PROZELL and FESTBATT clusters and as a member of the board of KLIB, Daniela knows the latest developments in research and industry and can incorporate them into the CUSTOMCELLS® technology. 2021 Daniela additional joined the Cellforce Group GmbH. At the Cellforce Group Daniela is responsible for the management of the IPCEI project as well as the scouting of new technologies for future cell generations.

Dr. Martin Ruge

Martin has been with CUSTOMCELLS® since February 2018. As a business developer and project manager for major projects in the automotive sector, Martin is now responsible for Industrial Engineering. Feasibility studies, process optimization and quality improvements are Martin's focus. He coordinates all customer projects and sets new standards with his team.

Katharina Anders

Katharina studied B.A. Economics and Law and M.A. Human Resource Management. During and after her studies, she also gained practical experience in human resources work in various companies. Her tasks ranged from operative human resources work to Europe-wide strategic human resources projects. Thus, she is ideally equipped for her area of responsibility at CUSTOMCELLS® - the comprehensive management of all HR topics.

Torge Thönnessen

Torge studied chemistry at Philipps-Universität Marburg and Lund University in Sweden. He began his professional career as a scientist at Fraunhofer ISIT in various projects to industrialize the production of lithium battery cells from laboratory scale to industrial scale. During this time he also worked for various start-ups to commercialize special types of lithium battery cell technology at battery system and electrode level. In 2012, Torge founded CUSTOMCELLS® as a spin-off of the Fraunhofer Gesellschaft. Since then he has worked as Managing Director for CUSTOMCELLS®, which has evolved from a start-up to a leading technology provider and prototype manufacturer for OEM, Tier-1, medical, aerospace and marine applications in a growing industrial market segment. Torge and his family live in Hamburg.

contact us now

We are at your disposal by phone at +49 4821 – 133 92 00. Alternatively you write us your request gladly by Mail to contact(at) and we contact you promptly. By indicating the CUSTOMCELLS® contact person of your choice, we will forward your enquiry directly to the person responsible.