Helping lithium-ion battery recyclers move forward  

Battery recycling is here to stay, insists Germany’s URT Umwelt- und Recyclingtechnik (URT Recycling Technology). Over the past ten years, the company has developed an expertise and solid business in building lithium-ion battery processing plants serving customers around the globe.

Lithium-ion battery recycling has been an essential part of e-mobility from the very beginning. The activity is justified by the high-quality scrap delivering important valuable materials required for the production of new batteries.

Germany’s URT Umwelt- und Recyclingtechnik has tackled lithium-ion battery recycling head on. The plant manufacturer has been operating in the wider recycling market for 30 years and became established by constructing plants to treat WEEE scrap, in particular end-of-life refrigerators. For more than 10 years now, it has developed another business expertise, the construction of plants for recycling lithium-ion batteries.

At the heart of URT are Florian and Peter Hessler and Bernhard Biener. Peter Hessler is the md, son Florian is an authorised signatory and responsible for sales while Biener is the company’s technical director.

HOW IT ALL BEGAN: LITHOREC-2

In 2011, the work started with an exciting project called LithoRec-2. The main goal was to develop mechanical, thermal and chemical processes for recycling lithium-ion batteries. Alongside partners Volkswagen and TU Braunschweig, URT was involved and built a prototype plant. Within the plant, it was possible to shred cells and cells packs and convert them into a homogeneous state under a nitrogen atmosphere.
This procedure was the starting point for all subsequent processing: thermomechanical drying, hydrometallurgical treatment or pyrometallurgical treatment.

PILOT PLANT

The knowledge gained from these development steps is the basis for today’s concept from the plant manufacturer. During those early days, recalls URT’s md Hessler, he did not expect LithoRec-2 to develop into an entire business segment. ‘After all, in 2011 all original equipment manufacturers in Germany were opposing electromobility,’ he says. ‘Nevertheless, URT has greatly developed the concept and built a pilot plant at Volkswagen in Salzgitter in 2020. This important step served to gather more know-how. As examples, this included the resistance of the sealing materials, bulk material behaviour and controlling the purities.’

98% RECOVERY

With this knowledge, URT has been building turnkey recycling plants at an industrial level using thermomechanical treatment since 2021. The advantage of this treatment is the preservation of lithium in the black mass. As a result, more than 98% of the dry black mass can be recovered by URT plants. Much of the solvent released in the process is also condensed and recovered. The construction of industrial plants has resulted in new requirements for throughput, operational safety and plant automation. Depending on the input requirements and emission guidelines of the individual countries, plants are always built specifically for the customer. For example, it is possible to double the throughput of the plant later on.

Essential here is the prior knowledge gained from constructing refrigerator recycling plants regarding inert shredding, airlock technology and how to prevent diffuse emissions, particularly the release of solvents from the electrolytes. ‘These are hydrogen-based, which is congruent with refrigerators,’ adds Hessler. ‘In this way, knowledge about explosivity and flammability can also be reused. This is a decisive factor for plant and operational safety.’

AT INDUSTRIAL SCALE

The current technology and process steps incorporate this knowledge. Beginning with the inert one step shredding, previously discharged batteries or battery parts are transported via sluice technology into a nitrogen-flooded shredder, where they are shredded to a specific size. The input material is then fed via bunker systems into one or more vacuum distillation dryers, where the solvents evaporate from the electrolytes and are subsequently collected.

Here it is essential to find the right temperature, residence time and vacuum to match the input and cell chemistry. In the next step, the entire output material is cooled and then enters the first screening machine, allowing a large part of the black mass to be screened. This early generation results in 70-80% of the dry black mass. The challenge here is to recover the black mass as pure as possible, with low impurities such as aluminium from the housings or organic materials and films. ‘The shredding process is crucial here,’ Hessler stresses.

MORE SEPARATION

Further on in the process, light-heavy separation then takes place. Light refers to anode and cathode foils, which subsequently enter delamination. There, previously vapour-deposited metal layers, aluminium and copper, are detached. These thin metal foils tend to ball up resulting in a certain homogenization of the metals.

Due to the enormous acceleration of the delamination, black mass detaches from the foil. Under heavy stream, housing parts are found that consist of ferrous materials, aluminium, hard plastics, and copper. These four fractions are separated from each other. Magnetic technology is used for separating plastics and non-ferrous metals are separated by eddy current separators due to the residual magnetism.

OPTIMISING THE PROCESS

URT cites two reasons for this method of process engineering: pollutant removal and the recovery of valuable substances. Pollutant removal defines the separation of volatile substances in electrolytes so this procedure makes it possible to separate black mass and recover recyclables. The goal is to recover the recyclables with the highest possible purity. These two reasons are the main strategy to optimise the process by reducing impurities to a minimum. The process technology is also supported by legal regulations which relate to the recovery rates of the manufacturers. The European Commission has published a regulatory framework that specifies the recovery of batteries for recycling (European Commission, 2023).

MAINTENANCE, FIRE PROTECTION

Asked what makes URT’s plant technology special, Florian Hessler says: ‘It’s not just about the process technology itself but also about the implementation. This includes, for example, proper maintenance access as well as fire protection’. In addition, stresses technical director Biener, there is the selection, design and combination of the components. ‘One example is the nitrogen supply. You’d think that the more nitrogen is supplied to the plant the safer the plant will be. However, too much nitrogen creates overpressure, which results in diffuse losses. Accordingly, a slight negative pressure is always required in the parts of the plant containing the solvents so that they do not escape into the environment but are extracted and captured with the raw gas. This is the only way they can be fed into an exhaust air treatment system. For the plant engineer, it is therefore essential that all parameters are in perfect alignment with each other so that the overall plant functions properly. This is what we at URT call our “know-how”’.

CURRENT PROJECTS

Currently, eight projects on four different continents are in progress. These are in various stages, from engineering and production to installation and commissioning. One plant has already been commissioned in Georgia, USA. Customers include recycling and waste management companies that offer their recycling services independently, as well as OEMs and cathode manufacturers.

Among these customers is Re.Lion.Bat Circular which gave URT an engineering contract to drive forward the site planning. This was followed by a supply and service contract. The company from Meppen, Germany plans to treat end-of-life batteries from the appliance sector as well as end-of-life automotive batteries. The throughput of this plant is therefore four tonnes of input per hour. The company’s goal is to initially recycle 20 000 tonnes per year, growing to 60 000 tonnes in the long term.

ADVANCED MONITORING

Being a German plant, it is regulated by the TA-Luft (Technical Instructions on Air Quality Control). The plant accepts discharged EV-modules or appliance batteries and goes fully downstream through the black mass to aluminium, copper, iron and plastic. Operating under a high level of automation, it offers advanced monitoring of input and output.

The project is achieved by URT by handing over the turnkey plant, including commissioning, training and after-sales service. URT supports the customer with documentation during the approval process.

RAMPING UP CAPACITY

By establishing its new business field, URT has significantly built up capacity over the past two years, especially in the areas of engineering and design. The company is convinced that battery recycling is here to stay and demand for recyclables recovery is very high globally. Capacities must therefore be expanded in line with the expected return volumes.

Specifically, there are two reasons within electromobility for this forecast. One is the return flow of batteries from electric vehicles that are already on the market. Florian Hessler says end-of-life volumes are slowly increasing but are not yet available in all countries. ‘This will change significantly over the next few years. Not to be neglected are the production scraps that are currently generated by giga-factories or new cell factories.’

This waste, including cell packs, can also be treated in a single stage with within URT’s plant concepts. The second reason is the phasing out of combustion engines when a very large coverage of electromobility will be available.

Biener also refers to the range of possible applications for lithium-ion batteries: ‘LIBS batteries are used not only in e-mobility but also in power tools, laptops and cell phones. In addition, there is a large amount of appliance batteries. Any kind of lithium-ion battery can be recycled with the battery recycling plants.’