Specification of Battery Management

System for Electrical Vehicle

Catalogue

Catalogue ..............................................................................................1

1. BMS Introduction ...........................................................................2

2. The Monitoring Cables ...................................................................2

2.1 Voltage monitoring cables ........................................................2

2.2 Temperature detecting cables....................................................4

3. Data Collection Module (DCM) .....................................................5

3.1 The Construction of the DCM ..................................................5

3.2 The Connection of the DCM ....................................................5

4. Central Control Module (CCM) .....................................................6

4.1 The function and the Construction of the CCM .......................6

4.2 The connection of the CCM with the other parts .....................7

5. Display Screen ..............................................................................10

5.1 Connection with CCM ............................................................10

5.2 Display Explanation................................................................10

6. Detailed List....................................................................................15

7. Technical Specification ...................................................................17

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1. BMS Introduction

The function of Battery Management System (BMS) is to monitor the battery and

protect it to be over-charged or over-discharged. It has the characteristics as follow:

Monitoring the voltage of each single cell;

Monitoring the temperature of the battery module;

Monitoring the current of the battery charging or discharging;

Calculating the state-of-charge (SOC) of the battery pack;

Calculating the maximum and minimum cell voltage of the battery pack;

Changing the protect parameters of the battery pack;

Communicating with charger and motor controller via CAN Bus;

Displaying all the information of the battery pack with a color touch screen;

The Battery Management System includes four parts:

The monitoring cables;

The Data Collection Module (DCM);

The Central Control Module (CCM);

The Display Screen;

This specification will explain the structure, function and the connection methods

of the BMS in details.

2. The Monitoring Cables

The monitoring cables of the BMS include the voltage

monitoring cables to detecting the voltage of each single cell, and the temperature

sensor cables to get the temperature of the battery module. There are also

communication cables and the BMS power lines, those will be introduced in the other

parts.

2.1 Voltage monitoring cables

The voltage monitoring cables are used to monitoring the voltage of each cell. At

first, cells should be serial connected using the wires (or sheet coppers etc.), the anode

of cell 1 connecting the cathode of cell 2, and so on. Then connect

the voltage monitoring cables with the battery cells:

The B1P connecting with the anode of cell 1;

The B1N connecting with the cathode of cell 1 (or the anode of cell 2);

… ;

The B10N connecting with the cathode of cell 10.

And if there are 16 cells in serial in a module, the B16N should be connected

2

with the cathode of cell 16.

There are schematic diagram and picture of the real product of the cable connection

with 10 cells in serial as below.

Fig.1 Schematic Diagram

Fig.2 Serial Connection of 10 Cells

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Fig.3 Connection of Cables and Cells

2.2 Temperature detecting cables

The temperature sensors are used to detect the temperature of the battery module. It

should be put on the battery cell and fixed.

Fig.4 Placing of Temperature Sensor

4

3. Data Collection Module (DCM)

The Data Collection Module is used to collect the data of the battery pack, such as

the voltage of the single cell and the temperature of the battery module,

one DCM could collect up to 16 cells’ voltage value and two temperature value.

3.1 The Construction of the DCM

The DCM has five ports connecting to the battery module and the Central Control

Module, and three LED to indicate the status of communication or

power. It is illustrated in Fig.5.

Fig.5 Ports of the DCM

3.2 The Connection of the DCM

The +12V power port supplies power source to the DCM by the +12VDC power

line (see Fig. 25).

The communication ports connect with another DCM or the

Central Control Module using the serial communication

cable. The screws of serial communication cables

should be fastened with screwdriver after installing. The two communication

ports of DCM are the same for using, and one port of the last DCM in serial

should be connected with the CCM.

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Fig.6 Connection of DCM

4. Central Control Module (CCM)

The Central Control Module (CCM) is the master controller of

the Battery

Management System, and it has the function of central process.

4.1 The function and the Construction of the CCM

The Central Control Module (CCM) is the master controller of

the Battery

Management System; the functions of CCM are mainly included as follow:

To communicate with DCMs to get the cell voltage and temperature value.

To measure the current value of the battery pack with a Hall sensor.

To estimate the state-of-charge (soc) of the battery pack.

To communicate with the charger through CAN BUS to avoid overcharge.

To supply +24VDC to the touch screen as power source.

To transit data to touch screen through LCD BUS.

The CCM has two power ports: one port is for the +12VDC power input, and the

other is the +24V power source output for the screen. And the CCM has three BUS

ports; there are the DCM communication port to get the data of DCMs,

the screen communication port to communicate with the screen, and the

CAN BUS port to communicate with charger or motor controller.

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Fig.7 Ports of CCM

4.2 The connection of CCM with other parts

The DCMs and the CCM of our BMS should use a +12VDC as power source. The

+12VDC may be supplied by a DC-DC or other DC power source in

vehicle. The touch screen uses a +24VDC as power source supplied by the CCM.

Fig.8 Connection Methods of the BMS

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Fig.9 Actual Connection of the BMS

Our BMS use a Hall sensor to measure the current of the battery pack. Wire which

connected to the battery pack’s positive pole or negative pole passes

through the sensor, and then the sensor can turn the current signal into

voltage signal. So the current value can be measured. There are two connection

modes for the current sensor. Either of the two modes can be chosen. (Pay attention to

the arrow flag on the sensor)

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Fig.10 Connection of Current Sensor

The cable connection port of the current sensor is in the one side of the CCM box.

Fig.11 Port of Current Sensor

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5. Display Screen

Our BMS use a 5.6’ colour liquid crystal touch screen to display

information of battery pack and charger. The dimensions of the

touch screen are

172mm×140mm×60mm.

5.1 Connection with CCM

The touch screen is powered by a +24VDC supplied by CCM. Also

the touch screen communicates with CCM to get the information to display.

Fig.12 Wires Connection of Touch Screen

5.2 Display Explanation

5.2.1 Running indicator

The running indicator includes three LED: the power (“PWR”),

the running

(“RUN”), the communication (“COM”).

Fig.13 LED of the Running Indicator

The states indicator explanations are as follows:

“PWR”: Light power input is normal;

“RUN”: Light CPU of the screen works normally;

Turned off faults on CPU;

“COM”: Spark communication with the CCM is normal;

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5.2.2 Information Display

Once we turn on the touch screen, the main interface is displayed.

Fig.14 Main Interface

Key information includes maximal cell voltage and minimal cell voltage

of the serial-connected battery pack, also the location of the cells in the pack. Once

there is

an alarm in the BMS, the alarm message will roll in the main interface, and the touch

screen beeps out a warning. Press “BEEP_OFF” can turn off the beep.

“PWR OFF” button is used to turn off the touch screen. If the

touch screen is turned off, touch anywhere of the screen can wake it up.

Press the “DETAILS” Button on the main interface can see

detailed battery information. And in other interfaces, press the “PREV”, “NEXT”,

“RETURN” button respectively can we get the previous interface, and the next

interface, and the main interface.

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Fig.15 Cell Voltage and Temperature

In the detailed cell module information interface, we use background color of the

cell voltage to represent the cell state. Red background

means the cell is over-discharged, White background means the

cell is normal, while yellow background means the cell is overcharged.

The screen also displays the information of charger.

Fig.16 Charger Information

On_Line State: OFF_Line No charger detected on CAN bus

ON_Line Charger detected on CAN bus

Start-Up State: ERR No battery pack connected to charger

Hardware State: ERR Charger’s hardware error

Input Voltage State: ERR AC input error

Temperature State: ERR Charger’s temperature is too high

Output Current: Real current output of charger

Output Voltage: Real voltage output of charger

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5.2.3 BMS Setting

We could also change the key parameters of BMS, press “LOGIN”

Button, a password input window is popped up.

Fig.17 Toolbar of Main Interface

Fig.18 Password Input window

There are two types of user: General User and Super Administrator. The password

of General User is 1111, and the password of Super Administrator is 8888. Once we

choose Super Administrator, we could use the “SET BMS” and “SET HMI” button. If

we want to cancel Super Administrator, we need only press “LOGOUT” button on the

toolbar.

Press “SET BMS” button, the BMS configuration window will appear.

Press

“READ” button, we can get all the current parameters.

Fig.19 BMS Configuration Window

We could press the value that we need to change, and there will be

a window popped up. Press the “Enter” button after inputting the new value, and then

press the

“APPLY” button. Waiting for about ten seconds, the new value

will be set

successfully. We could press the “ESC” button to quit the operation.

Fig.20 Value Inputting Window

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6. Detailed List

No.

Name

Specs

Quantity

Remark

1 CCM 54S 1

2 DCM 15S 1

3 DCM 14S 2

3 DCM 11S 1

4 Touch Screen 5.6 Inches 1

5 Charger 192V/12A 1

6 Serial Communication

Cable

1m

3

7 Serial Communication

Cable

4m

1

8 CAN Bus Cable 3m 1

9 Touch Screen Power

Cable

3m

1

10 Touch Screen Bus Cable 3m 1

11 +12VDC Power Line 3m 5

12 Voltage Monitoring Cable 15S/1m 1

13 Voltage Monitoring Cable 14S/1m 2

13 Voltage Monitoring Cable 11S/1m 1

14 Temperature Sensor 1m 4

15 Current Sensor 500A 1

16 Current Sensor Cable 3m 1

17 Specification 1 See PDF

There are the pictures of the cables below.

Fig.21 Serial Communication Cable Fig.22 CAN Bus Cable

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Fig.23 Touch Screen Power Cable Fig.24 Touch Screen Bus Cable

Fig.25 +12VDC Power Line Fig.26 Voltage Monitoring Cable

Fig.27 Temperature Sensor Fig.28 Current Sensor Cable

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7. Technical Specification

Alarming Condition(Recommended):

The alarming voltage of overcharge: 3800mV

The release of overcharge voltage: 3400mV

The alarming voltage of over-discharge: 2500mV

The release of over-discharge voltage: 2800mV

Power:

Power source of DCM and CCM: +12VDC (±10%);

Power source of touch screen: +24VDC (±5%);

Measure range and accuracy:

Cell Voltage measuring range: 0~5V

Cell Voltage measuring accuracy: ±5mV

Current measuring range: 0~500A

Current measuring accuracy: ±0.5A

Temperature measuring range: -25℃~99℃

Temperature measuring accuracy: ±1℃

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