Specific advantages and successful implementation of modular mini-environments for the production of lithium-ion cells

The production of Li-ion cells involves moisture-sensitive processes that are carried out in large multifunctional drying rooms. Dehumidified air is crucial to avoid possible negative quality losses due to humidity influences. Dehumidifying the air to the required dew points is one of the most energy-intensive processes.

Drying rooms therefore play a significant role as energy guzzlers in battery cell production. A typical drying room in a battery cell gigafactory requires 25%[1]) of the total energy demand, assuming average dew points and internal humidity loads. New cell chemistries could require even more stringent dew point requirements, resulting in even higher energy demand.

Energy saving measures and emission reduction are top priorities for cell manufacturers, and OEMs are committing to carbon neutrality by 2035 at the latest to ensure sustainability. Mini-environments are one of the technical solutions to these challenges. By reducing the sources of humidity (no operators, less leakage due to lower overall volume), mini-environments require much less air for dehumidification, resulting in lower capital expenditure (CAPEX) and reduced energy requirements (OPEX).

This presentation addresses the challenges outlined above and answers the question of how a modular mini-environment system must be designed in order to overcome them in the best possible way. As a result, the implementation of a highly modular, flexible and individually climate-controlled environment for battery cells was developed and will be presented.

1) Benjamin Dorn, PEM Aachen, KLIB discussion round pilot lines, 10.2022