Novel Materials for Anodes and for Battery Thermal Management Systems of Secondary Ion Batteries

Abstract

The electrification of transportation plays a pivotal role in achieving the UK's net-zero targets, emphasizing the critical need for advancements in battery technology. This thesis addresses the critical challenge of advancing the battery technologies by demonstrating two innovative approaches; 1) to design and develop novel anode materials for lithium-ion (LIBs) and sodium-ion batteries (SIBs), 2) exploring novel materials for battery thermal management systems (BTMS) using additive manufacturing techniques.
Anode materials for both LIBs and SIBs face several challenges. Materials such as Molybdenum Trioxide (MoO3) and Sn are potential candidates for anode materials for both LIBs and SIBs however these materials encounter issues like low electronic conductivity and significant volume expansion during charge-discharge cycles, leading to decreased electrochemical performance and reduced battery cycle life. Similarly, in SIBs, the larger ionic size of sodium poses challenges for conventional graphite anodes, limiting their capacity and stability. Overcoming these challenges requires innovative approaches to enhance conductivity, mitigate volume fluctuations, and ensure robust cyclic stability in both types of batteries.
In the 1st section of the thesis, this study begins with exploration of an in-depth analysis ofMoO3 as an anode material for LIBs, focusing on its inherent challenges such as low electronic conductivity and significant volume expansion during cycling. A hard carbon (HC) layer is deposited onto MoO3 electrodes via Physical Vapour Deposition (PVD). The resulting MoO3/HC composite exhibits an exceptional capacity of 953 mAhg-1 at 0.1C, alongside excellent rate capability and cyclic stability exceeding 3,000 cycles. Similarly, Sn based anodes are developed for LIBs utilizing PVD processes, leading to Sn/HC composites with enhanced capacity (763 mAhg-1 at 0.1C) and remarkable stability under rapid charging conditions. Similarly, a nanostructured SnHT/HC anode was employed as an anode material for SIBs which exhibited a high initial capacity and exceptional cycling stability over 3,000 cycles.
To summarise the 1st section of thesis, the results conclude that when MoO3 and Sn utilized as pristine materials, both materials exhibited limited charge/discharge capacities and are prone to instability, leading to reduced battery cyclic performance in both LIBs and SIBs. However, the integration of HC layer proves to be transformative in mitigating these challenges. By effectively addressing issues such as volume fluctuations and poor conductivity, the HC layer enhances cycle stability and overall battery efficiency. Through a combination of microstructural optimization
and HC layer integration, both MoO3 and Sn anodes demonstrate significantly improved electrochemical performance, even under high charge-discharge rates, thereby highlighting the critical role of HC in enhancing their functionality.
In the 2nd section of the thesis, this study focusses on designing and developing novel materials for BTMS of LIBs using additive manufacturing (3D printing) technique. BTMS play a pivotal role in ensuring the safe and efficient operation of LIBs. The thermal behaviour of LIBs is inherently complex, with factors such as internal resistance, heat generation during charge and discharge, and environmental conditions influencing their performance and longevity. Without adequate thermal management, LIBs are susceptible to overheating, which can lead to thermal runaway, degradation of battery materials, and even safety hazards such as fires or explosions. However, BTMS encounter several challenges efficient heat dissipation, uniform temperature distribution, energy efficiency, integration with battery packs, real-time monitoring and control, safety considerations, and minimizing environmental impact.
This study demonstrated a novel approach of developing new materials using 3D printing technique to achieve these goals. Various 3D printed materials are evaluated for BTMS applications, encompassing PLA, ABS, PETG, PVA, PLA/1% Cu, PLA/CF, and PLA/steel composites. Through systematic experimentation and simulation using COMSOL, the results show that materials such as PLA/CF and PVA emerge as promising candidates compared to other tested materials. Both PLA/CF and PVA, offer favourable thermal properties, cost-effectiveness, and recyclability.

Date of Award	28 Nov 2024
Original language	English
Awarding Institution	Northumbria University
Supervisor	Shahid Rasul (Supervisor) & Carolina Costa Pereira (Supervisor)