A NUMERICAL APPROACH FOR THE DESIGN OF A NOVEL THERMAL MANAGEMENT SYSTEM FOR THE BATTERY PACKS OF ELECTRIC VEHICLES BASED ON LTO CHEMISTRY

THE RAPID ELECTRIFICATION OF THE TRANSPORT SECTOR HAS HIGHLIGHTED THERMAL MANAGEMENT SYSTEMS (TMSS) AS A CRITICAL FACTOR FOR THE SAFETY AND PERFORMANCE OF LITHIUM-ION (LI-ION) BATTERY PACKS. SIMPLE AND RELIABLE METHODS TO INVESTIGATE THE THERMAL BEHAVIOURS OF LI-ION CELLS ARE ESSENTIAL FOR THE ELECTRIC VEHICLES (EVS) INDUSTRY TO PREDICT KEY ISSUES WHEN DESIGNING DEDICATED COOLING SYSTEMS. MEANWHILE, INNOVATIVE COOLING SOLUTIONS MUST ALIGN WITH THE FUTURE DIRECTIONS OF MAJOR INDUSTRY PLAYERS TO IMPROVE CURRENT MATURE AND RELIABLE TECHNOLOGIES, BRIDGING THE GAP BETWEEN ACADEMIC RESEARCH AND INDUSTRIAL DEVELOPMENT. THIS REPORT AIMS TO DEVELOP A SIMPLIFIED THERMAL MODEL TO ANALYSE THE THERMAL BEHAVIOUR OF CYLINDRICAL LI-ION BATTERY CELLS, INCORPORATING A DEDICATED EQUIVALENT CIRCUIT MODEL (ECM), THE BERNARDI ET AL. EQUATION, AND EMPIRICAL CORRELATIONS FOR THE NUSSELT NUMBER IN NATURAL CONVECTION. THE MODEL WAS VALIDATED AGAINST EXPERIMENTAL DATA, ACHIEVING ERRORS WITHIN ±5% AND RMSE OVER 95%. THE WORKFLOW AND APPROACH WERE APPLIED TO DESIGN AN INNOVATIVE COLD PLATE SYSTEM COMPOSED OF HORIZONTAL AND VERTICAL THE RAPID ELECTRIFICATION OF THE TRANSPORT SECTOR HAS HIGHLIGHTED THERMAL MANAGEMENT SYSTEMS (TMSS) AS A CRITICAL FACTOR FOR THE SAFETY AND PERFORMANCE OF LITHIUM-ION (LI-ION) BATTERY PACKS. SIMPLE AND RELIABLE METHODS TO INVESTIGATE THE THERMAL BEHAVIOURS OF LI-ION CELLS ARE ESSENTIAL FOR THE ELECTRIC VEHICLES (EVS) INDUSTRY TO PREDICT KEY ISSUES WHEN DESIGNING DEDICATED COOLING SYSTEMS. MEANWHILE, INNOVATIVE COOLING SOLUTIONS MUST ALIGN WITH THE FUTURE DIRECTIONS OF MAJOR INDUSTRY PLAYERS TO IMPROVE CURRENT MATURE AND RELIABLE TECHNOLOGIES, BRIDGING THE GAP BETWEEN ACADEMIC RESEARCH AND INDUSTRIAL DEVELOPMENT. THIS THESIS AIMS TO DEVELOP A SIMPLIFIED THERMAL MODEL TO ANALYSE THE THERMAL BEHAVIOUR OF CYLINDRICAL LI-ION BATTERY CELLS, INCORPORATING A DEDICATED EQUIVALENT CIRCUIT MODEL (ECM), THE BERNARDI ET AL. EQUATION, AND EMPIRICAL CORRELATIONS FOR THE NUSSELT NUMBER IN NATURAL CONVECTION. THE MODEL WAS VALIDATED AGAINST EXPERIMENTAL DATA, ACHIEVING ERRORS WITHIN ±5% AND RMSE OVER 95%. THE WORKFLOW AND APPROACH WERE APPLIED TO DESIGN AN INNOVATIVE COLD PLATE SYSTEM COMPOSED OF HORIZONTAL AND VERTICAL MINICHANNELS FOR A 40 AH LTO BATTERY PACK USED IN EVS. RESULTS SHOWED THAT THE PROPOSED TECHNOLOGY MET THE THERMAL TARGETS FOR EACH BATTERY CELL, MAINTAINING TEMPERATURES BETWEEN 20 AND 30 °C AND TEMPERATURE SPANS BELOW 5 °C. ADDITIONALLY, THE DESIGN KEPT BULK AND VOLUME INCREASES MINIMAL THROUGH A COMPACT AND LIGHTWEIGHT STRUCTURE, ENSURING COMPATIBILITY WITH EV APPLICATIONS.