MULTI-CELL LITHIUM-ION BATTERY MANAGEMENT SYSTEM

For Electric Vehicle

Team Members• Pramit Tamrakar- Electrical Engineering• Jimmy Skadal- Electrical Engineering• Hao Wang- Electrical Engineering• Matthew Schulte- Electrical Engineering

Advisor• Ayman Fayed

Client• Adan Cervantes- Element One Systems

Team-id- SdMay11-04

Project Goals and System Diagram Design a Lithium Ion Battery Charger that is capable of safely

charging 16 parallel packs of 90 cells in series.

Successfully build a small scale 18 cell charger that is capable of monitoring and balancing the scaled down system.

MSP430 Launch Pad Buck Circuit

Bq76pl536EVM-3Evaluation moduleFor battery management

Functional Decomposition (Hardware)

Functional Decomposition (Software)

UCC28019AEVM Boost Circuit Will supply the needed maximum 324

volts to the buck circuit for the large scale charger

350 W Power Factor Correction (PFC) boost converter

390 VDC regulated output

0.9 A of load current

Advanced fault protection

Buck circuit and Feedback Loop The buck circuit will take the

voltage generated by the boost buck down to cells

The negative feedback loop

Negative feedback tends to compare actual voltage with desired voltage and seeks to reduce the difference

Scaled down buck circuit

Inductor 100uHCapacitor 330uF

Value of components

Battery Management System Texas Instruments bq76PL536EVM-3 and

MSP430 microcontroller to monitor and regulate the Li-Ion batteries and send information packet to the processor.

Battery Management System Programming using C and WinGUI Use SPI with an MSP430 to gather the

data and make decisions based on battery status

Implementation of the bq76pl536 with 6 series cells in each

Test Plan Subsystem test:

• Boost Converter • System DC supply

• Buck Converter • All necessary voltages and currents

• Battery Management System communication• USB-SPI Processing GUI

Integration Test (scaled down):• 18 cell charge/discharge• 32.4V-72V CC, 72V CV until 0.3A to batteries

Schedule Progress

Cost BreakdownItem W/O Labor With LaborParts and Materials:  

a. Previous school sessions $402.51 $402.51

b. Printed Circuit Boards $50.00 $50.00

c. Discrete components $100.00 $100.00

d. Texas Instruments ICs $0 $0

e. TI PFC boost converter $50.00 $50.00

f. MSP430 programming board $150.00 $150.00

Subtotal: $752.51 $752.51

Test and Build equipment  

a. oscilloscope, function generator, digital multimeter, PSU $0 $0

b. soldering equipment $0 $0

Subtotal: $0 $0

Labor at $20.00/hour:  

a. Previous school sessions $28,000

b. Hao Wang $4,000

c. Pramit Tamrakar $4,000

d. Matt Schulte $4,000

e. Jimmy Skadal $4,000

Subtotal: $0 $44,000

Texas Instruments endowment: ($200) ($200)

Total: $552.51 $88,752.51

Questions ?