<p>Ceramic matrix composite phase change materials suffer from inherently low thermal conductivity due to solid particle contact limitations in ceramic skeleton, restricting concentrated solar energy storage applications. This study presents a bioinspired heterostructured composite that emulates the hierarchical sieve tube structures in Bombax ceiba vascular bundles to create anisotropic phonon transport channels. Integrating directionally aligned silicon carbide fibers within a porous SiC matrix via centrifugal flow-assisted alignment achieves three-dimensional anisotropic thermal conductivity. This design bypasses the high thermal resistance of sintered particle junctions using biomimetic "sieve plate-like" fiber networks. Elongated SiC fibers act as unidirectional heat conduits, minimizing phonon scattering at grain boundaries. At the expense of 9.4% total energy storage capacity, this anisotropic CPCM significantly optimized equipment performance in the required heat transfer direction. Compared to pure sodium acetate trihydrate and ordinary CPCM, the thermal conductivity in the expected direction improved by 281.19 % and 29.63 %, respectively. The energy storage rate increased by 60.54 % and 36.6 %. The maximum temperature difference in the heat transfer direction decreased by 50.39 % and 31.75 %, and the junction temperature difference reaching the working limit was reduced by 66.83 % and 52.18 %. Therefore, this CPCM efficiently and stably realized thermal energy storage, providing a research basis for building and distributed energy storage.</p>