High‐Performance Thermally Conductive Phase Change Composites by Large‐Size Oriented Graphite Sheets for Scalable Thermal Energy Harvesting

Abstract

Efficient thermal energy harvesting using phase‐change materials (PCMs) has great potential for cost‐effective thermal management and energy storage applications. However, the low thermal conductivity of PCMs (KPCM) is a long‐standing bottleneck for high‐power‐density energy harvesting. Although PCM‐based nanocomposites with an enhanced thermal conductivity can address this issue, achieving a higher K (>10 W m−1 K−1) at filler loadings below 50 wt% remains challenging. A strategy for synthesizing highly thermally conductive phase‐change composites (PCCs) by compression‐induced construction of large aligned graphite sheets inside PCCs is demonstrated. The millimeter‐sized graphite sheet consists of lateral van‐der‐Waals‐bonded and oriented graphite nanoplatelets at the micro/nanoscale, which together with a thin PCM layer between the sheets synergistically enhance KPCM in the range of 4.4–35.0 W m−1 K−1 at graphite loadings below 40.0 wt%. The resulting PCCs also demonstrate homogeneity, no leakage, and superior phase change behavior, which can be easily engineered into devices for efficient thermal energy harvesting by coordinating the sheet orientation with the thermal transport direction. This method offers a promising route to high‐power‐density and low‐cost applications of PCMs in large‐scale thermal energy storage, thermal management of electronics, etc.

Interfacial jamming reinforced Pickering emulgel for arbitrary architected nanocomposite with connected nanomaterial matrix

“…1a ), which shows the benefits in thermal management 16 , 17 , thermal energy storage and harvesting 15 , 18 , 19 , supercapacitors 14 , and Li–S batteries 20 . However, their manufacturing technologies are limited to post-infiltration and layer-by-layer casting, which hardly engineer them into 3D structures and have hampered their rapid innovations and broad applications 18 , 19 , 21 . Therefore, a 3D printing strategy is required to reveal defined geometry and functionality distribution; however, it faces stringent challenges in preparing printable multiphase inks with nanomaterial continuous phase or solidifying printed structures.…”

Near-Zero-Energy Smart Battery Thermal Management Enabled by Sorption Energy Harvesting from Air

“…To overcome the major disadvantage of poor thermal transfer performance, recent studies have been devoted to enhancing the thermal conductivity of PCMs by synthesizing phase-change composites with highly conductive additives. 15 − 17 …”

Toward Tailoring Chemistry of Silica-Based Phase Change Materials for Thermal Energy Storage

“…The best solution is to prepare composite PCMs by packaging PCMs into supporting materials ( Chen et al., 2020a ; Lin et al., 2018b ; Qureshi et al., 2018 ). To date, the most popular is carbon supporting materials, especially graphene and carbon nanotubes (CNTs) materials ( Aftab et al., 2019 ; Cao et al., 2019 ; Hu et al., 2020 ; Qian et al., 2018 ; Shin et al., 2016 ; Song et al, 2019 ; Tang et al, 2019 ; Wang et al., 2019b ; Wu et al, 2019 ; Xue et al., 2019 ; Zhang et al., 2019a , 2019b , 2019d ; Zhang and Liu, 2019 ). Undoubtedly, highly thermally conductive carbon materials can accelerate thermal transfer and boost the charging/discharging rates of composite PCMs.…”