To address the existing problems of commercial inorganic cathodes, including relatively low capacity, poor rate performance, structural instability, and low conductivity, it is critical to introduce a conductive matrix accompanied with electrochemical activity. Conductive polymers have great potential as electrodes with good conductivity, high redox activity, and potential. In this study, carbon-coated lithium iron phosphate (C-LiFePO4) nanoparticles were effectively dispersed in a polypyrrole (PPy) matrix by in situ pulverization. PPy, as an active nanostructure, significantly improves conductivity and accelerates Li+ diffusion. To further explore the synergy and symbiosis mechanism of PPy and C-LiFePO4 (hereinafter called C-LFP in the composite), the nanoparticle dispersion, carburization dependence, and heat treatment preference were investigated. Therefore, a reasonable amount of PPy (25 wt %) hybridization, a moderately wrapped carbon buffer layer (5.3 wt %), and a suitable heat treatment (100 °C) were employed to prepare the (C-LFP)0.75(PPy)0.25 nanocomposite. With a smaller particle size, uniformly dispersed morphology, and good synergy effect between PPy and C-LiFePO4, (C-LFP)0.75(PPy)0.25 delivers a high discharge capacity (209.1 mAh g–1 at 0.1C), a superior rate capability (86.1 mAh g–1 at 10C), and an outstanding capacity retention (83.5% of the initial values after 500 cycles at 0.5C).

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Limited by leakage from inherent liquid to solid phase transition and inferior heat transfer, pristine organic phase change materials (PCMs) possess extremely low thermal storage performance. Thus, establishing shape-stable PCM composites with enhanced thermal conductivity and latent heat is a key task for practical application. Herein, we constructed N-doped mesoporous carbon monoliths with a highly aligned structure by directional freeze-drying to encapsulate polyethylene glycol. Benefiting from the mesoporous carbon matrix and pyridinic N from N-doping, the PCM composite possessed large latent heat (140 J·g–1) and leakage proof at 80 °C. Meanwhile, the highly aligned structure created a fast heat transfer pathway that improved thermal conductivity of the PCM composite by 1500%. Being different from most research studies, highly aligned carbon was utilized as the support directly without skeletons, which could increase PCM loading capacity and thermal conductivity as well. The PCM composite can be employed as promising candidates for thermal management working efficiently to decrease battery pack temperature by 13 °C and improve discharge capacity by 28%.