Cellulose nanocrystal (CNCs) assisted carbon nanotubes (CNTs) and graphene nanoplatelets (GnP) were used to modify the interfacial region of carbon fiber (CF) and polymer matrix to strengthen the properties of carbon fiber-reinforced polymer (CFRP). Before transferring CNC-CNTs and CNC-GnPs on the CF surface by an immersion coating method, the nanomaterials were dispersed in DI water homogeneously by using probe sonication technique without additives. The results showed that the addition of CNC-CNT and CNC-GnP adjusted the interfacial chemistry of CFRP with the formation of polar groups. Furthermore, according to the single fiber fragmentation test (SFFT), the interfacial shear strength (IFSS) of CNC-GnP 6:1 and CNC-CNT 10:1 added CFRP increased to 55 MPa and 64 MPa due to modified interfacial chemistry by the incorporation of the nanomaterials. This processing technique also resulted in improvement in interlaminar shear strength (ILSS) in CFRPs from 35 MPa (neat composite) to 45 (CNC-GnP 6:1) MPa and 52 MPa (CNC-CNT 10:1).
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Development of Novel Carbon Fiber based Electrodes for Lithium-ion Batteries
Carbon fiber-based structural lithium-ion batteries are attracting significant attention in the automotive and aerospace industries due to their dual capability of energy storage and mechanical load-bearing, leading to weight reduction. These batteries utilize lightweight carbon fiber (CF) composites, which offer excellent stiffness, strength-to-weight ratios, and electrical conductivity. Polyacrylonitrile-based CFs, comprising graphitic and amorphous carbon, are particularly suitable for Li-ion battery applications as they allow the storage of lithium ions. However, integrating lithium iron phosphate (LFP) into CFs poses challenges due to complex lab-scale processes and the use of toxic dispersants, hindering large-scale industrial compatibility. To address this, we investigate the development of water-based LFP-integrated CF structural Li-ion batteries. Homogeneous suspensions are created using cellulose nanocrystals (CNCs) to form hybrid structures. The battery system employs LFP-modified CF as the cathode, unsized CF as the anode, and a water-based electrolyte. The LFP-CNC-graphene nanoplatelet (GNP) hybrids are coated onto CFs through immersion coating. Scanning electron microscopy (SEM) images confirm the well-dispersed and well-adhered LFP-CNC-GNP structures on the CF surface, contributing to their mechanical interlocking and electrochemical performance. The batteries demonstrate a specific energy density of 62.67 Wh/kg and a specific capacity of 72.7 mAh/g. Furthermore, the cyclic voltammetry experiments reveal the stability of the LFP-CNC-GNP-coated CF batteries over 200 cycles without degradation. This research enables the engineering of hybrid nanostructured battery laminates using novel LFP-CNC-GNP-coated CFs, opening avenues for the development of innovative Li-ion structural batteries.
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- Award ID(s):
- 1930277
- PAR ID:
- 10470695
- Publisher / Repository:
- American Society for Composites-DESTech publications
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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