BMRA service member BHS-Sonthofen, together with its subsidiary AVA, has developed a process that allows for the safe and efficient recycling of lithium-ion accumulators and batteries. In addition to a reliable process, the focus is on ensuring the usability of the end products. 

At the heart of the process is a shredder from BHS and a vacuum dryer from AVA, which joined the BHS Group in 2018.

As fossil fuels are increasingly replaced by other energy sources, it’s important to have an efficient and safe process to allow the raw materials from depleted batteries and accumulators to be returned to the material cycle.

Safe process for battery recycling

Before the batteries can be shredded safely, they first need to be discharged. Following this, a BHS shredder selected according to the feed material (cells or battery modules) is used in the first shredding stage. If the batteries have not been treated with a thermal process at high temperatures, sparks in the machine can cause the electrolyte to catch fire. In order to eliminate this risk, a customised shredder that has been made gas tight and that operates in a nitrogen atmosphere is used.

Once the shredding tools have reduced the feed material to the desired target size, the parts fall through appropriately designed grid segments. The shredded batteries are heated in batches in a vacuum dryer from AVA located directly downstream to evaporate the electrolyte components for subsequent recovery in a condensation unit. The electrolyte-free residues are then subjected to dry mechanical processing consisting of various screening, separating and ball-shaping steps.

The system size, which can be adjusted depending on customer requirements, ranges from 100 kg to several tons. “The process delivers the following three end products: high-grade aluminum concentrates, copper concentrates and black mass, which contains lithium and various other metals such as manganese, cobalt and nickel. All three fractions are ready for remarketing,” explains Christian Kühn, Sales Director for Recycling & Environmental Technology at BHS. “Another advantage for many of our customers is that the products of the small plant do not fall under ADR regulations during transport.”

Fine processing of incinerator bottom ash

In a presentation that will be take place at IFAT, as well as, in addition to the new process for battery recycling, BHS-Sonthofen focuses on the processing of incinerator bottom ash. The slags resulting from waste incineration contain about 15–20 percent metallic components. When recycling the slags, the aim is to obtain metal concentrates that are as pure as possible. The BHS-Sonthofen process is based on the combined use of an impact mill (type PM) and rotor impact mill (type RPMX). The latter will be showcased to IFAT visitors live at the BHS stand in September.