<p>The growing demand for high-capacity lithium-ion batteries, driven by the development of compact portable devices and long-range electric vehicles, necessitates significant advancements in electrode design. Increasing electrode thickness is among the most effective strategies for enhancing performance and reducing manufacturing costs in lithium-ion batteries. However, thick electrodes are often prone to delamination, crack formation, and elevated internal resistance resulting from extended lithium-ion diffusion pathways. In this work, a simple and efficient method for fabricating thick electrodes is demonstrated by using lithium iron phosphate slurry–coated carbon nanotube (CNT) films, yielding bifunctional CNT-based thick electrodes (BCTE) that enable simultaneous electron transport through the interconnected CNT network and Li⁺ percolation through electrolyte-filled porous pathways formed by the CNT-film architecture. Electrochemical measurements reveal that the CNT film–based electrodes exhibit a lithium-ion diffusion coefficient nearly twice that of conventional thick electrodes even when normalized to total carbon content, confirming that the performance enhancement originates from the CNT architecture rather than from carbon loading differences. The specific capacity of 148.3 mAh g⁻¹ is maintained under a substantial active material mass loading (135&#xa0;mg cm⁻²), with superior rate capability and stable Coulombic efficiency at a current density of 1&#xa0;mA cm⁻². These findings underscore the potential of this facile fabrication approach for enabling advanced thick electrode architectures, supporting the broader adoption of high performance lithium-ion batteries.</p>