Constructing efficient conductive networks is essential to overcome the intrinsically low electronic conductivity of LiFePO4 cathodes. Previous studies have demonstrated that different conductive agents possess distinct electrical conduction mechanisms. The synergistic integration of multiple types of conductive agents can achieve more favorable conductive performance. Nevertheless, most relevant studies are still limited to binary conductive systems, and the synergistic mechanism among various conductive agents has not been systematically investigated and deeply analyzed. In this work, a multidimensional ternary conductive system composed of Super P carbon black (SP), graphene (GN), and carbon nanotubes (CNTs) was systematically optimized to regulate electron and ion transport pathways. By adjusting the relative proportions of SP, GN, and CNTs, the evolution of conductive network structure and its impact on electrochemical performance were investigated, and the optimized composition (SP/GN/CNTs = 50/15/35, denoted as S5GC37) was identified. The results reveal that the multidimensional conductive framework formed by S5GC37 effectively integrates short-range ion diffusion with long-range electron transport, leading to reduced polarization, suppressed surface oxidation, and enhanced charge transport kinetics. As a result, the LiFePO4 electrode with S5GC37 delivers an initial discharge capacity of 164.8 mAh·g−1 and maintains 151.9 mAh·g−1 after 200 cycles at 1C. Even at 3C, a capacity retention of 83.2% is achieved after 200 cycles, demonstrating excellent rate capability and cycling stability. These findings highlight the importance of multidimensional conductive network design for high-performance LiFePO4 batteries.
Zeng et al. (Sat,) studied this question.