ALD for the electrochemical stockage of energy

In the face of global warming and the rapid advancement of digital technologies, global demand for energy storage solutions is skyrocketing. High-capacity batteries with fast charging capabilities and long lifespans are needed to electrify the vehicle fleet, store renewable energy, and power the many electronic devices we use in our daily lives. Miniaturized energy sources, meanwhile, are needed to power miniature devices for Internet of Things (IoT) applications or for medical devices.

France and the European Union support numerous research, innovation, and industrialization projects in the field of energy storage, bringing together academic institutions, government agencies, and industry players. In particular, France can draw on the French Network for Electrochemical Energy Storage (RS2E), which was created in 2011 and brings together seventeen academic laboratories, sixteen industrial partners, and three technology transfer and integration centers, as well as on the establishment of several industrial battery production sites (gigafactories).

Currently, the dominant battery manufacturing technology is based on the use of lithium (Li) as a charge carrier. Although other technologies are under study or in the early stages of commercialization, lithium-based technologies are far more mature.

However, numerous issues are hindering the widespread use and development of batteries: the instability of lithium-based materials or other battery components when exposed to air (primarily due to water), dependence on rare elements, and limitations in charging speed or lifespan. Although battery manufacturing is based on the complex chemistry of powders, thin-film deposition technologies can provide solutions to these problems by adding thin protective layers to various battery components.

Atomic layer deposition (ALD) combines all the qualities required to synthesize these protective layers: deposition is possible in a conformal manner on any type of material (dispersed powder, compacted powder, flat or textured substrates); a wide range of materials is available; and the layers can be as thin as a few nanometers, are dense, and are free of pores. This article demonstrates the value of ALD in the field of manufacturing both large-scale and miniaturized batteries.