Reducing carbon emissions has been a target for every player across every industry in recent times. In the automotive industry, this target has led to the invention of several alternate fuel options, earning the decade the title of ‘decade of alternate fuel’. One such alternative fuel option is electrification. It is said that electric vehicles are the future of mobility. But are they?
Although EVs emit no tailpipe emissions, when the well-to-wheel situation is considered, EVs do cater to environmental pollution due to the batteries used. When an electric vehicle battery pack degrades to 70% to 80% of its original capacity, it is considered end-of-life, and one of the waste management options is to reuse it. More value can be derived from the battery pack by repurposing it for stationary storage, while the per kWh lifecycle impact is reduced. However, allowing batteries to have a second life is complicated due to several obstacles impeding the growth of the battery refurbishing industry.
To solve this, under the leadership of the Volkswagen Group, TANIOBIS GmbH, J Schmalz GmbH and Viscom AG are working together with researchers from RWTH Aachen University, TU Braunschweig and the Fraunhofer Institute for Surface Engineering and Thin Films (IST), for three years to research and develop the necessary processes. The project is being funded by the Federal Ministry for Economic Affairs and Climate Action. The aim is to jointly showcase that the most valuable components of traction batteries can be recovered and reused several times in succession through recycling.
The HVBatCycle research consortium aims to permanently keep cathode metals, electrolytes and graphite in a closed material cycle (closed-loop).
Sebastian Wolf, Chief Operating Officer Battery Cell, Volkswagen AG, said, “Through the HVBatCycle project, a holistic view of the recycling processes and thereby the implementation of the closed loop of battery materials is being prepared.”
The consortium project focuses on the mechanical-hydrometallurgical recycling route, characterised by low energy requirements and the possibility of a comparatively simple decentralised distribution of specific recycling processes in Europe. This favours a local circular economy and secures strategically important raw materials, which significantly reduces Europe’s dependence on other regions of the world.
Michael Kellner, Parliamentary State Secretary, said, “European battery production can only be successful if it focuses on sustainability in as many areas as possible. Sustainable batteries are crucial for an energy and transport transition that is guided by high environmental and social standards.”
The HVBatCycle project aims to identify efficient processes and innovative solutions that ensure the establishment of an end-to-end value chain with high economic efficiency while, at the same time, maximising recycling and energy efficiency and minimising environmental impact.
Working Of The Project
In the hydrometallurgical processing of the ‘black mass,’ which consists of graphite and battery metals, using water and chemical solvents, the focus is on early and selective extraction of the lithium in soluble form as well as leaching, precipitation and refining of contained metals as a mixed hydroxide concentrate.
Here, in connection with the renewed material synthesis of cathodic active material, it will investigate whether the separation of metal compounds is essential to produce new, fully high-performance cathode material.
The research on the processing of the electrolyte and the graphite is intended to show, through the development of suitable processes, that important electrolyte components and the graphite can also be efficiently processed and used again in battery-suitable quality in cell production. All process steps are holistically accompanied by an ecological and economic life cycle analysis.
Closed Raw material Cycle, Multiple Recycling
To use fewer materials from primary sources such as mines or salt flats, essential raw materials are to be recovered not just once but several times.
To this end, battery cells made from recycled material are recycled again, thereby proving that even multiple recycling runs do not influence the material quality.
Closing the loop requires complex interdisciplinary processes. For efficient and ecologically and economically sensible recycling, all processes must be coordinated with each other to produce sorted and high-quality secondary materials under the highest safety requirements. This is about scalability and economic efficiency, in particular.
Team Behind The Project
As part of its battery strategy and sustainability strategy, Volkswagen AG has shown interest in the realisation of a closed loop of cell materials and has therefore taken on the coordination and management of the project. With the pilot plant for mechanical recycling at the Salzgitter components site, the Group’s Technology division ensures the production and supply of recyclable material from vehicle batteries. In addition, the cell manufacturing expertise of the Centre of Excellence in Salzgitter is used to produce new cells from entirely recycled material. TANIOBIS GmbH is a quality supplier of powders containing niobium and tantalum for hydrometallurgical manufacturing processes, including solvent extraction.
With its knowledge of hydrometallurgical recycling of lithium-ion batteries, the company will build and operate the required hydrometallurgical and pyrometallurgical infrastructure at the Chemiepark Oker site, where a certified analytical laboratory is also available.
While the supplier of vacuum technology, J Schmalz GmbH, will supply all the vacuum components needed to assemble grippers for industrial robots. In addition, sensor technology from Schmalz ensures process efficiency and safety. Furthermore, in joint projects with scientific institutes, handling systems for silicon wafers and cathode and anode foils were established.
With specialisation in various cell formats, such as pouch or prismatic cells, covering different sizes for consumer products through energy storage to e-mobility cells, Viscom AG will develop X-ray measurement solutions specifically for use in the battery cell industry.
The Battery LabFactory Braunschweig (BLB), an established transdisciplinary research centre of the TU Braunschweig and one of the leading institutions in the field of battery research in Germany, will act as the R & D platform for circular production, diagnostics and modelling/simulation of batteries of the current and future generations.
In its pilot plant, the BLB combines engineering process know-how, materials science expertise, battery cell system knowledge from the natural sciences and sound analytical skills. The Institute of Machine Tools and Production Technology (IWF) will focus on technological and automation issues and current and future manufacturing process chains for battery cells. The elenia Institute for High Voltage Technology and Power Systems has extensive experience in formation, cyclic ageing and the electrical and electrochemical characterisation of battery cells.
At the Institute for Particle Technology (iPAT), mechanical and particle technology processes for producing battery materials and electrodes and mechanical and thermal methods for battery recycling are investigated.
The Institute of Chemical and Thermal Process Engineering (ICTV) has broad expertise in separating fluid mixtures. The Institute of Energy and Process Systems Engineering (InES) has many years of experience in the modelling and simulation of batteries and electrochemical analysis, and operando analytics.
The Fraunhofer Institute for Surface Engineering and Thin Films (IST) conducts intensive research and development in material synthesis and functionalisation, surface treatment and modification, film production and application, film characterisation and surface analysis, as well as in the field of production technology. As a central topic at the Fraunhofer Project Center for Energy Storage and Management Systems (ZESS), battery research focuses on material and energy storage development, including associated process and manufacturing technologies, as well as the holistic and sustainable design of the life cycle.
The Institute for Metallurgical Process Engineering and Metal Recycling (IME) at RWTH Aachen University has many years of experience in application-oriented research into battery recycling processes. The research focuses on recovering the valuable metals contained in batteries using thermal and hydrometallurgical processes. The institute has a comprehensive infrastructure for testing various recycling concepts, including an innovative pyrolysis furnace from Otto Junker GmbH for processing larger quantities or entire battery modules.
Through its in-house certified laboratory, the IME has access to many critical analytical methods needed to investigate possible battery recycling processes.