Solar Jackets’ Racer Battery Management

System(BMS)Ali Bibonge

Daniel ChristopherPaul MartinMark Slade

Taverishima Tsegha

Solar Jackets’ Racer Battery Management

System(BMS)Ali Bibonge

Daniel ChristopherPaul MartinMark Slade

Taverishima Tsegha

December 7th, 2011

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BMS Project OverviewBMS Project Overview

Battery monitoring system for a solar powered race car

Maintain batteries in a “safe to operate” and efficient state

For Solar Jackets’ entry into the American/World Solar Challenge

Overall BMS cost of $1200

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Proposed Design ObjectivesProposed Design Objectives

It monitors: Li-ion cell over/under voltages Li-ion cell over current Battery pack over temperature

Electrically isolate the Li-ion cellsTransmits or receives acquired data via

RS-485 to racer systems

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Current Design FunctionalityCurrent Design Functionality

It monitors: Li-ion cell over current Battery pack over temperature

Electrically isolate the Li-ion cellsThe RS-485 communication component

has been incorporated into the BMS PCB and is ready for programming

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BMS System Flow ChartBMS System Flow Chart

PrototypingPrototyping

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PrototypingPrototyping

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TestingTesting

Something here...

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Demonstration of Temperature Sensor Demonstration of Temperature Sensor

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Demonstration of Current Sensor Demonstration of Current Sensor

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System Development ProblemsSystem Development Problems

Programming of the LTC chip for measuring voltages

The LTC chip has been included on the PCB for further programming

Georgia Tech milling machine is broken

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Final BudgetFinal Budget

Total amount spent is approximately $400

This covers the electromechanical relay, LM 35 temperature sensors, ACS758 current sensors, DC fuse/fuse holder, and copper bus/connectors

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Battery Module and Cell ThresholdsBattery Module and Cell Thresholds

Green Zone

Yellow Zone

Red Zone

Temperature

< 40 C 40 C - 45 C > 45 C

Discharge Current

< 40 A 40 A - 60 A > 60 A

Charge Current

< 16 A 16 A - 18 A > 18 A

Voltage (module)

85 V - 103 V

103 V - 105 V

> 105 V

Voltage(Li-ion cell)

2.6 V - 3.3 V

3.3 V - 3.6 V

2.3 V - 2.6 V

> 3.6 V< 2.3 V

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Recommended Future WorkRecommended Future Work

LTC programming Incorporating the electromechanical

relay into the battery box RS-485 programming Mounting PCB components

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Questions?