This study investigates the piezoionic effect in chemo-mechanical energy harvesting systems based on carbon nanotube (CNT) yarns. The research aims to understand the fundamental mechanisms and kinetics of cations and anions within these systems, which are crucial for generating electrical energy from mechanical motion. The study employs experimental and computational approaches, including in situ Raman scattering, piezoelectrochemical impedance spectroscopy (PEIS), and molecular dynamics (MD) simulations. Key findings include: 1. **Experimental and Computational Approaches**: The study combines in situ Raman spectroscopy to analyze ionic motion, PEIS to study ionic conductivity, and MD simulations to model ionic cluster behavior. 2. **Ionic Kinetics and Conductivity**: In situ Raman spectroscopy reveals that anion depletion occurs during mechanical stretching, leading to increased open-circuit voltage (OCV). PEIS and EIS analysis show that ionic conductivity significantly affects harvester performance, with higher conductivity resulting in better output current. 3. **Multiscale Modeling**: MD simulations and DFT calculations provide insights into the transport kinetics of hydrated ion clusters on MWCNT surfaces. The results highlight the importance of ion cluster structure and rigidity in determining energy harvesting performance. 4. **Piezoionic Energy Harvesting Mechanism**: A comprehensive model is proposed, explaining how mechanical deformation of CNT bundles affects the electrical double layer (EDL) and ion kinetics, leading to electrical energy generation. The study concludes that optimizing ion mobility, conductivity, and cluster structure is essential for enhancing the performance of piezoionic chemo-mechanical energy harvesters. This research has significant implications for the development of sustainable energy solutions in various applications.This study investigates the piezoionic effect in chemo-mechanical energy harvesting systems based on carbon nanotube (CNT) yarns. The research aims to understand the fundamental mechanisms and kinetics of cations and anions within these systems, which are crucial for generating electrical energy from mechanical motion. The study employs experimental and computational approaches, including in situ Raman scattering, piezoelectrochemical impedance spectroscopy (PEIS), and molecular dynamics (MD) simulations. Key findings include: 1. **Experimental and Computational Approaches**: The study combines in situ Raman spectroscopy to analyze ionic motion, PEIS to study ionic conductivity, and MD simulations to model ionic cluster behavior. 2. **Ionic Kinetics and Conductivity**: In situ Raman spectroscopy reveals that anion depletion occurs during mechanical stretching, leading to increased open-circuit voltage (OCV). PEIS and EIS analysis show that ionic conductivity significantly affects harvester performance, with higher conductivity resulting in better output current. 3. **Multiscale Modeling**: MD simulations and DFT calculations provide insights into the transport kinetics of hydrated ion clusters on MWCNT surfaces. The results highlight the importance of ion cluster structure and rigidity in determining energy harvesting performance. 4. **Piezoionic Energy Harvesting Mechanism**: A comprehensive model is proposed, explaining how mechanical deformation of CNT bundles affects the electrical double layer (EDL) and ion kinetics, leading to electrical energy generation. The study concludes that optimizing ion mobility, conductivity, and cluster structure is essential for enhancing the performance of piezoionic chemo-mechanical energy harvesters. This research has significant implications for the development of sustainable energy solutions in various applications.