Carbon Nanotube Dispersion for Low-Viscosity Battery Electrode Slurries

The patent introduces a dispersant as an intermediary substance between carbon nanotubes and the electrode matrix. This dispersant contains specific functional groups that interact with carbon nanotubes through van der Waals forces and π-π interactions, preventing direct nanotube-nanotube aggregation while maintaining their conductive properties. The dispersant acts as a mediator that separates nanotubes individually or in small bundles, enabling uniform distribution throughout the electrode without compromising electroconductivity.

The patent modifies the surface properties of carbon nanotubes by changing parameters such as surface functionalization, dispersion medium composition, and processing conditions. By adjusting these parameters, the patent optimizes the balance between maintaining nanotube integrity for conductivity and achieving sufficient dispersibility. Specific parameters include the type and concentration of dispersant, ultrasonic treatment intensity, and drying conditions, all of which are tuned to prevent agglomeration while preserving conductive pathways.

The patent applies preliminary action by incorporating a dispersant into the system before or during the mechanical dispersing process. This dispersant pre-establishes repulsive interactions between carbon nanotubes, creating a stable dispersed state that persists after ultrasonic treatment ceases. The dispersant adsorbs onto nanotube surfaces, forming a protective layer that prevents re-agglomeration over time, thereby extending the duration of stable dispersion without requiring continuous mechanical energy input.

The patent ensures continuity of useful action by using a dispersant that maintains repulsive forces between carbon nanotubes continuously, even after the initial ultrasonic dispersing stops. The dispersant creates ongoing steric and electrostatic barriers that prevent nanotube aggregation, sustaining the dispersed state indefinitely under appropriate storage conditions. This continuous protective action eliminates the need for repeated mechanical treatment and maintains dispersion stability over the electrode's service life.

The patent applies segmentation by using carbon nanotubes as discrete, fiber-like conductive elements distributed throughout the electrode matrix. Unlike bulk conductive additives that require high compression to achieve density, nanotubes maintain their structural integrity and create conductive networks at lower densities. The segmented, one-dimensional structure of nanotubes allows them to bridge particle spaces without requiring complete particle deformation, thus maintaining electrolyte permeability while achieving high energy density through improved active material utilization.

The patent creates a composite electrode structure combining active material particles with carbon nanotube conductive additive. This composite approach allows the electrode to achieve high density through optimized particle packing while the nanotube network provides conductive pathways that are less sensitive to compression-induced pore closure. The composite structure maintains hierarchical porosity, preserving electrolyte access to active material surfaces even at high densities, thereby simultaneously improving energy density and maintaining reliability of ion transport.