DMT GROUP 12 BATTERY THERMAL MANAGEMENT Timothy Engstrom Willem Hilbers Ryan Prosser Sofie Shackcloth Kulwinder Basuta TEAM MEMBERS OBJECTIVES Create a TMS system that maintains cell tab temperature below 40 o C Design cases to protect and mount the battery modules onto the bike Design module interconnection system, considering electrical safety 74 cells integrated onto bike giving predicted range > 80 miles. Batteries fit within BMW R65 envelope Welded aluminium cases built to withstand impact at 70mph. Cases lined with foam to absorb vibrations and impact energy. Simple cable and pipe routing allowing easy assembly. RESEARCH SUMMARY Degradation of battery is increased as temperatures rise above 50°C. Active thermal management enables fast charging while maintaining battery longevity. Tab cooling design: Reduces cell degradation compared to conventional surface cooling increasing life cycle by a factor of 3 [1] Space efficient allowing a higher energy density and extended range THE THERMAL MANAGEMENT SYSTEM Reduced the temperature increase from a 40 minute (1.5C) discharge by 25%. Increased the cooling rate by a factor of 2.1. Reduced intra-cell temperature variation by 10%, which improves cell resistance balancing. PARALLEL AND SERIES FLOW Parallel gives constant fluid temperature Series is easier to obtain consistent flow Series was chosen as temperature change is minimal. MODULE COMPONENTS The module includes the following features: Compression plate Electrical connection and fuse mount Skirt Clamps Slit plate with hidden Cooling Block Assembly - connects cell tabs to each other Cooling Mount—Supports TMS Slit plate support bars Battery Management System Cooling Block Assembly 1 2 3 4 [1]I. A. Hunt, Y. Zhao, Y. Patel and G. J. Offer, “Surface cooling causes accelerated degredaon compared to tab cooling for lithium-ion pouch cells,” (under review), 2016. COOLING BLOCK ASSEMBLY MODULE CASING AND BIKE INTEGRATION Acetal Waterblock O-ring Aluminium Cold plate Polypropylene Insulator/ Locator Thermally conductive, electrically insulating Alumina 1 2 3 4 5 5 6 7 8