The existing performance capacity of mobile end devices, drones, electric vehicles or within the framework of stationary storage of renewable energies would not exist today without correspondingly powerful lithium-ion batteries. The range of lithium-ion batteries is divided into different cell types depending on the application. Depending on the application area of the cell, various components and material combinations are used.
The numerous combination possibilities result in many possibilities for the optimization and adaptation of lithium-ion cells - also with regard to their specific application. The development of post-lithium systems also offers enormous optimization potential. The investigation of new bonding systems for electrode production, the generation of higher SI components of the anode to increase capacity or the investigation of magnesium-sulfur cell chemistry are just a few examples of the potential development opportunities in the lithium-ion battery segment.
In order to remain at the forefront of technological development, CUSTOMCELLS®, together with numerous interdisciplinary partners from research and industry, is continuously involved in public cooperation projects to research new materials and concepts and to develop new innovations for special applications.
The SOLIFLY project has three vertical objectives. First, to explore and further develop a non-conventional formulation of a semi-solid Li-ion battery material suitable for structural batteries: NMC622 (cathode), Si/C (anode), and bicontinuous polymer ionic liquid electrolyte (BCE), i.e., NMC622|BCE|Si/C. Second: Enabling the functional integration of this material within CCF and RMS concepts, targeting the level of a representative aeronautical stiffened panel structure. Third, the SOLIFLY demonstrator aims to achieve a cell-level gravimetric energy density between 100 and 180 Wh/kg at a nominal discharge rate of 1C. The cell shall be capable of 300+ cycles at 0.1C with 90% capacity retention. Overall, the concept shall be at a TRL level of 4. CUSTOMCELLS® is creating an industrialization concept for this innovative technology in cooperation with the partners.
This project has received funding from the Clean Sky 2 Joint Undertaking (JU) under the European Union’s Horizon 2020 research and innovation programme under grant agreement No 101007577. The JU receives support from the European Union’s Horizon 2020 research and innovation programme and the Clean Sky 2 JU members other than the Union.
Sustainable, high-quality carbon additives are essential to further enhance the performance of Li-ion batteries. In the HiQ Carb project, high-purity conductive additives and high-quality carbon nanotubes are being developed and manufactured by the leading European material manufacturers. The developed high quality carbon additives and carbon nanotubes will be used to manufacture the high energy and high performance cathodes. CUSTOMCELLS® will use the developed carbon additives and optimized recipes to scale up electrode manufacturing and produce pilot cells with high power density and high energy density, respectively.
The aim of the project is to increase the silicon content of the anode up to 25 % - and thus significantly compared to the state of the art - by means of novel nanoporous silicon powders, which can be manufactured via a cost-effective, environmentally compatible (free of hydrofluoric acid) and easily scalable process. The project also aims to combine the newly developed anode with a commercially available next-generation cathode (high nickel content) to produce a large-format pouch cell. Computationally, this development is expected to increase the energy density above 350 Wh/kg and 1,000 Wh/l in pouch cells. CUSTOMCELLS® will participate in the anode paste development and battery cell production as part of the RoSiLiB project.
The NeuroBatt project aims to generate a database by systematically testing lithium-ion batteries with integrated optical sensors. By means of cyclic and calendrical aging tests as well as dynamic impedance spectroscopy, an AI-supported prognosis tool for the condition determination and lifetime prediction of electrical energy storage devices will be developed and evaluated. In the project, CUSTOMCELLS® is developing intelligent pouch cells that provide the data for the prognosis tool by integrating sensors. A particular challenge here is the direct integration of an optical fiber into the electrode coating of the cells, which will later provide data on local pressure and temperature differences in the cells via optical measurements, among other things. The AI-supported evaluation of this data makes it possible to optimize the operating strategies of electrochemical energy storage systems in order to limit aging effects or to detect them at an early stage.
In the InterBatt project, CUSTOMCELLS® is developing a new type of cell technology which, based on an "all solid state" concept, is to be projected onto the processes currently in use. To achieve this goal, systematic adjustments are being made to the manufacturing technologies. Anode materials and coated anode foils will be developed and further processed in cooperation with the partners. A cathode specially designed for the construction of test cells is to enable rapid market access for this technology after the end of the project. The electrochemical characteristics of the cells will be integrated into the evaluation of the market situation.
The 3beLiEVe project aims to strengthen the position of the European battery and automotive industry by delivering the next generation of battery cells, developed and manufactured in Europe, for the electric vehicle market. CUSTOMCELLS® focuses on the development of automotive battery cells with high performance (high energy density, fast charging capability, long lifetime) that are free of critical raw materials such as cobalt and natural graphite. In addition, the integration of sensors in and on the cells is being investigated. This should enable intelligent, adaptive operating strategies and advanced diagnostics to extend the useful life of the battery in applications.
This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 875033.
The aim of CUSTOMCELLS® is to develop a battery technology installed in vehicles that enables rapid charging within a period comparable to a "classic refueling stop" of less than ten minutes. The disadvantages associated with fast charging processes in terms of battery life and safety are drastically reduced by this novel technology. In the Power400 project, CUSTOMCELLS® is working closely with research institutions and universities. This joint project is an important step towards decarbonizing the public transport system and thus towards climate protection.
The goal of this collaborative project is to develop and implement high capacity anodes for Li-ion cells. This will be achieved by using composites of a novel active material, Si nanowires (Si-NW) and graphite, as anode active material. The work will be carried out in collaboration with materials specialist ENWIRES. CUSTOMCELLS® will use its own flexible electrode fabrication line to contribute to the research of suitable electrode recipes. The resulting electrode will be applied in pilot cells, and the appropriate test protocols will also be investigated and applied.
The KomVar funding project involves the development and establishment of series production of high-quality lithium-ion battery cells in small to medium volumes at the CUSTOMCELLS® site in Tübingen. The BMWi-funded project was officially approved on 01.09.2019 and, with a total volume of 8.2 million euros (4.7 million in funding) over 24 months, is pushing the development of competitive variant production for lithium batteries with a service character for lithium-ion cell development and for the production of small and medium series for niche markets. CUSTOMCELLS® will be involved in all work packages. Tasks in the project include support in planning and construction of the facilities as well as development and supply of electrode foils for the test production runs. Furthermore, CUSTOMCELLS® will also be involved in the quality tests on the cells.
The collaborative project aims to demonstrate the performance of a new reversible energy storage technology based on magnesium and sulfur in an industry-compatible battery cell. The project follows on from the developments of the MagS project (2016-2018). The focus of MagSiMal is on the further development of all individual components of the magnesium-sulfur cell, but especially the anode and cathode active materials and the electrolyte. As a result, the capacity and cycle stability of the magnesium-sulfur cells are to be increased to 400 mAh/g(sulfur) and 40 cycles. In the project, CUSTOMCELLS® is developing concepts for processing and handling the novel cell components. Due to the improved moisture and oxygen resistant active materials, cell assembly can be performed in a manufacturing environment similar to lithium-ion cells. CUSTOMCELLS® manufactures and characterizes magnesium-sulfur cells in various cell formats up to VDA format (BEV1) to further advance the commercialization of this technology.
New Li-ion batteries meet the highest safety standards at temperatures up to 150 °C. Even under extreme application conditions, such as in deep geological drilling, they reliably supply energy for sensors and can be charged on site. The batteries are available for a variety of other applications. Conventional lithium-ion battery cells only guarantee safe use and an acceptable life expectancy within a limited temperature range (typically 0 °C to 40 °C, maximum 60 °C). Other energy storage systems such as lithium metal batteries allow higher application temperatures, such as those found in deep drilling, but at the same time have a high risk potential and are not rechargeable. When operating so-called MWD (Measurement While Drilling) devices, in which the measuring equipment is integrated into the drill string behind the drill rig, the sensors used must be supplied with energy. This is done by a generator in the drill head, which is driven by the drilling fluid, but does not provide the same power throughout. Therefore, batteries that can withstand the extreme conditions are needed as an energy buffer.
The product and its innovation
Stimulated by the need for MWD equipment to measure boreholes, Custom Cells Itzehoe GmbH, the Fraunhofer Institute for Silicon Technology (ISIT) and the Canadian company Evolution Engineering Inc. have set themselves the goal of developing lithium-ion batteries that are particularly safe and can be discharged and charged at high temperatures. This would eliminate the need to change the batteries that were previously necessary for drilling. In the ZIM cooperation project, ISIT has developed a concept for magnetic field-reduced cells in Li-Ion technology, while Custom Cells Itzehoe concentrated on the development of high-temperature resistant battery cells based on a novel Li-Ion cell chemistry with new material combinations. The Canadian partner Evolution Engineering Inc. was responsible for assembling the cells into battery packs, adapting the battery management system and conducting field tests.
The market and customers
As a result of the development and production of the first sample series, CUSTOMCELLS® offers customer-specific configurable Li-ion battery cells that can be reliably charged and discharged in the temperature range from 0 °C to 150 °C, offer a high degree of safety against thermal penetration and metal fire and can be used with a long service life even under harsh environmental conditions. The market potential for high-temperature lithium-ion batteries is large. In addition to the already existing use in borehole measurements, there are many other possible applications. They are suitable as energy suppliers, for example, for the wireless energy supply of medical technology devices that are hot sterilised, for monitoring safety-relevant or particularly hazardous areas where high ambient temperatures can occur, or as energy back-up systems for actuators in safety-critical areas where high temperatures occur in the event of a disaster.
The cooperation partners
Custom Cells Itzehoe GmbH, founded in 2012 as a spin-off from the Institute for Silicon Technology of the Fraunhofer Gesellschaft (ISIT), is one of the world's leading companies in the development of application-specific lithium-ion battery cells. The Fraunhofer ISIT in Itzehoe is one of the most modern research institutes for microelectronics and microsystems technology in Europe. In close cooperation with partners from industry, miniaturised components for power electronics and microsystems for sensor and actuator technology are developed here. For more than 20 years, research has also been conducted at ISIT on new Li accumulators. The Canadian company Evolution Engineering Inc. of Calgary (province of Alberta) participated in the cooperation project without ZIM funding. Founded in 2011, the company focuses its research and development on sensor-based solutions to various technical problems and is a specialist for MWD devices.
The Fab4Lib project was funded by the German Federal Ministry of Education and Research under grant number 03XP0142. The project aimed to research innovative solutions along the value chain of lithium-ion technology and to validate them in demonstrators, thus laying the foundation for the establishment of large-scale production of lithium-ion cells in Europe. In eleven work packages, the collaborative partners with CUSTOMCELLS® focused on topics such as energy-autonomous infrastructure, cell design, innovative production processes and materials, Industry 4.0 or recycling strategies. At the end of the project, a competitive production unit with a production capacity of approximately 6 GWh p.a. was developed. In the future, the unit can be built up modularly and many times where the corresponding capacity is needed.
New Li-ion batteries meet the highest safety standards at temperatures up to 150 °C. Even under extreme application conditions, such as in deep geological drilling, they reliably supply energy for sensors and can be recharged on site. In the CHITS project, rechargeable lithium-ion cells suitable for an extended temperature range were developed. In the ZIM cooperation project, ISIT had developed a concept for magnetic field reduced cells in Li-ion technology, while CUSTOMCELLS® focuses on the development of the high temperature resistant battery cells based on a novel Li-ion cell chemistry with new material combinations.
The goal of the ECO COM'BAT project was to combine and scale up the combination of the most ecological and high performance materials possible for the next generation of high volt Li-Ion batteries. The production of an ORMOCER® coated NMC 622 and the lithium salt LiFSI were scaled up to batch sizes of about 10 - 20 kg. In addition, improvements in energy and power density were investigated using the structured carbon additives Porocarb® and Graphistrength®. CUSTOMCELLS® developed pilot cells from these novel and sustainable materials that showed improved performance compared to cells with industrial reference samples.
In the joint project MagS, the high potential for magnesium-sulfur batteries with high capacities at greatly reduced costs was demonstrated. In practice, however, there are still many challenges with the sulfur cathode, the high overpotential of the magnesium anode and the development of a suitable electrolyte system. Together with the project partners, CUSTOMCELLS® has successfully implemented the goal of developing magnesium-sulfur battery cells within a pouch-bag in a larger VDA format and manufacturing them within a pilot production. Within the MagS project, experimental investigations and theoretical studies were also carried out in order to achieve a better understanding of the mechanism of the magnesium-sulfur battery and thus an improved performance.
In the joint project SiGgI, CUSTOMCELLS® successfully demonstrated the transition of silicon (Si) carbon (C) composite technology from laboratory to industrial scale. The project included material development of silicon-carbon composites, comminution of Si/C milling beads to nanometer scale, and electrochemical surface treatment of silicon anodes. A process for pilot-scale fabrication of silicon-carbon electrodes was also developed. CUSTOMCELLS® was responsible for the fabrication of the demonstrator and the necessary scale-up of the Si-C electrode fabrication.
How can lithium-ion batteries be manufactured more sustainably? In answering this question, the binders used in the electrodes also play an important role. They should be harmless to health and, in the spirit of the bioeconomy, contain as high a bio-based content as possible. In a research project funded by the German Federal Ministry of Food and Agriculture (BMEL) through the Agency for Renewable Resources (FNR), the Technical University of Braunschweig, the Thünen Institute and CUSTOMCELLS®, as well as Schill + Seilacher "Struktol" as an associated partner, tested the suitability of bio-based epoxy hardener systems as a substitute for the common petrochemical and halogenated binders.