1. Senior Design II Final Presentation December 1, 2009

2. Team Members Jonathan Chapman Duties: Recharging Major: Electrical Engineering Quoc Dang Duties: Recharging Major: Computer Engineering Quintin Grice Duties: Power Circuit Major: Electrical Engineering Richard Teeple Duties: Communication, System Monitoring Major: Computer Engineering David Smith Duties: Fault Protection, System Monitoring Major: Computer Engineering

3. Overview Problem Solution Constraints Technical Practical Design PCBs Enclosure Bill of Materials Testing

5. Problem When dealing with lithium ion battery systems, the following aspects must be taken into consideration: Safety Fire and Explosion Communication CAN-bus System Life Weakest Link (individual cell)

6. Solution A rechargeable battery system that offers the following: Total output current monitoring Ambient temperature monitoring Individual cell voltage monitoring CAN-bus communication

8. Technical Constraints Name Description Battery Technology The technology used to output voltage from the REBATEM must be lithium ion cells. AccuracyVoltage: 0 to 5 volts with an accuracy of ± 0.1 volts Current: 0 to 6 amperes with an accuracy of ± 20 milliamps Temperature: -30 to 200 °F with an accuracy of ± 2 °F Capacity / Cycle Life The REBATEM must maintain at least an 80% state of charge for the individual cells and a minimum of a 400-cycle life.

9. Technical Constraints (cont.) Name Description Fault ProtectionDisconnect the cells from the system when temperature passes 175 °F or when current passes 10 amps. OutputOutput voltage must be within 12 to 16 volts. CommunicationThe battery management system must communicate cell voltages, temperature and current to external devices.

11. Environmental Green energy Contains no toxic metals Cadmium Lead

12. Safety Unstable - needs to be monitored Sony battery recalls UL 1642 [1]

14. PCB - Main

15. PCB - Charge

16. PCBs Charge Board PCB Main Board PCB

17. Enclosure Side View Inside View

18. Enclosure Front View Back View

19. Bill of Materials Main Board (X1) PIC24HJ32(1)$7.00 INA219(1)$3.76 ISL9208IRZ(1)$7.51 MCP2551(1)$1.12 Other Discrete Components$20.00 PCB(1)$33.00 Charge Board (x1) MOSFET 2N-CH(1)$1.20 MAX745EAP(1)$11.61 MAX931CPA(1)$2.46 Other Discrete Components$20.00 PCB(1)$33.00 Enclosure (Estimated)$50.00 Total:$190.65

21. Total Output

22. Accuracy-Voltage Setup (No Load) VM-13.69 BMS-13.693.703.693.71 Tol-10.000.010.000.02 VM-24.00 BMS-24.02 4.034.04 Tol-20.02 0.030.04 Results

23. Accuracy-Current Setup (Test Load = 14.9 Ω) BMS- Voltage (V) Shunt (A) Ammeter (A) Tol 15.030.9750.960.015 15.040.9750.960.015 15.040.9750.960.015 15.020.9750.960.015 15.030.9750.960.015 15.040.9750.960.015 Results

24. Accuracy-Temperature Setup (No Load) Monitored (°C)Measured (°C)Absolute Error 21.2821.20.08 21.3221.30.02 33.2532.40.85 32.3132.40.09 31.9332.30.37 33.6333.20.43 Results

25. CAN Communication

26. Charging Cells

27. Any Questions?

28. References: [1] [Online] Available: http://www.gadgetreview.com/wp-content/uploads/2006/08/explosion_dcrop1.jpg. [2] “Lithium Batteries.” [Online]. Available: http://ulstandardsinfonet.ul.com/scopes/scopes.asp?fn=1642.html.