Single Wall Carbon Nanotubes for Lithium-Ion Cells

Any material breaks under stress, including battery materials, which now face substantial pressure from the emerging electric vehicle industry’s demands for longer lifetimes, lower weight, and cost efficiency. In physics terms, batteries now need to store more energy in a shorter period, leading to rapid material degradation and breakage.

Single wall carbon nanotubes—one of nature’s strongest materials—offer a solution to this problem. They create a 3D network that reinforces battery electrodes, providing enhanced conductivity and flexibility, which suppresses degradation and extends battery life.

To put it simply, if we think of an electrode as a bookshelf and lithium ions as books, our goal is to maximize the bookshelf’s capacity while ensuring it remains stable as books are added and removed during charge/discharge cycles. Graphene nanotubes act like reinforcement bars for the bookshelf’s framework. Not only do they enhance the structure’s stability but they also allow us to make the bookshelf thinner while maintaining its strength, thereby creating more space for books.

Whether using silicon and graphite at the anode or LFP and NCM at the cathode, or even in next-generation lithium-sulfur or solid-state batteries, the principle remains the same: excessive energy causes material breakage. Graphene nanotubes prevent this, making them a crucial component in advanced battery technology.

Nature’s longest and most flexible material

FOR CONDUCTIVITY AND REINFORCEMENT OF ELECTRODE 

Single wall carbon nanotubes, also known as graphene nanotubes, due to their highly distinctive intrinsic properties, demonstrate the unique ability to form robust long-distance electrical networks connecting particles of active battery material. 

A single wall carbon nanotube can be imagined as a one-atom-thick sheet of graphene rolled into a tube with a diameter of about 1.6 (± 0.4) nanometers and a length of around 5 microns. An extremely high aspect length-to-diameter ratio of more than 3,000, and a low amount of structural defects due to the graphene-like nature, result in the high length, flexibility, unmatched conductivity, and strength of graphene nanotubes and the bundles they form.

These intrinsic characteristics fundamentally differentiate single wall carbon nanotubes from other carbon-based materials for batteries, such as multi-wall carbon nanotubes or carbon black. Bundles of graphene nanotubes are able to create conductive, lоng, flexible bridges between electrode particles in a manner that's totally unique compared to other materials.

The ability to connect electrode particles at long distances allows graphene nanotubes to outperform alternative materials in many essential applications.