Battery management system

1. A battery management system comprising:

a computing device comprising:

an output data request port; and

an input data port;

a first battery unit monitoring coupled with a first battery unit and comprising:

an input data request port connected to the output data request port or the computing device; and

an output data request port;

an output data port connected to the input data port of the computing device; and

a second battery unit monitoring module coupled with a second battery unit and comprising:

a single input data request port connected only to the output data request port of the first battery unit monitoring module, therein defining a module connection between said first battery unit monitoring module and said second battery unit monitoring module;

an output data port connected to the input data port of the computing device;

wherein the first battery unit monitoring is a master to said second battery unit monitoring module and the second battery unit monitoring module is a slave to the first battery unit monitoring module,

wherein the first battery unit monitoring module responds to a data request signal from the output data request port of the computing device by transmitting data of the first battery unit to the input data port of the computing device and subsequently transmits a data request to the second battery unit monitoring module through said module connection; and

wherein the second battery unit monitoring module responds to the data request from the output data request port the first battery unit monitoring module by transmitting data of the second battery unit to the input data port of the computing device;

wherein the computing device receives data from the first and second battery unit monitoring modules sequentially after sending a single data request signal to only the first battery unit monitoring module; and

wherein the computing device receives data from the second battery unit monitoring module automatically after receiving data from the first battery unit monitoring module.

2. The battery management system of claim 1 , wherein the first battery unit monitoring module connects to a first battery unit for an electric vehicle.

3. The battery management system of claim 1 , wherein the first battery unit monitoring module comprises an analog-to-digital converter that measures a voltage of the first battery unit.

4. The battery management system or claim 1 , wherein the first battery unit monitoring module comprises a temperature monitoring device that measures a temperature of the first battery unit.

5. The battery management system of claim 1 , wherein the data of the first batter unit is a voltage and a temperature of the first battery unit.

6. The battery management system of claim 5 , wherein the data of the second battery unit is a voltage and a temperature of the second battery unit.

7. The battery management system or claim 1 , wherein the computing device is configured to scan the first and second battery unit monitoring modules to determine a number of battery unit monitoring modules in the battery management system.

8. The battery management system of claim 1 , wherein the computing device transmits a second data request to the first battery unit monitoring module after the computing device has not received data on the input data port for a predetermined period of time.

9. The battery management system of claim 8 , wherein the predetermined period of time is 20 ms.

10. The battery management system of claim 1 , wherein the computing device further comprises an analog-to-digital convertor that measures a voltage across the first and second battery units.

11. The battery management system of claim 1 , wherein the computing device further comprises an analog-to-digital convertor that measures a current flowing in the first and second battery units.

12. The battery management system of claim 1 , wherein the computing device is configured to output an alarm when an error condition is detected.

13. The battery management system of claim 12 , wherein the error condition is as high voltage condition, a low voltage condition, a high current condition, a high temperature condition or a connection fault condition.

14. The battery management system of claim 1 , wherein the computing device is configured to shut off a battery charge when the computing device detects a high voltage condition across the first and second battery units.

15. The battery management system of claim 1 , wherein the computing device is configured to shut off a load when the computing device detects a low voltage condition across the first and second battery units.

16. The battery management system of claim 1 , further comprising a monitor that is configured to display the data of the first and second battery units.

17. The battery management system of claim 1 , further comprising a connection fault detector that to detects a connection between a chassis and the first and second battery units.

18. The battery management system of claim 1 , further comprising a battery unit balancing system that is configured to balance the first battery unit.

19. A battery management system comprising:

a computing device with an output data request port, an input data port and an analog-to-digital convertor that measures a voltage across a first and a second battery unit;

a first battery unit monitoring module coupled with a first battery unit and comprising:

a first input data request port connected to said output data request port of said computing device,

a first output data port connected to the input data port of said computing device, and

a second output data request port; and

as second battery unit monitoring module coupled with as second battery unit and comprising:

a single input data request port consisting of a second input data request port connected to the second output data request port of the first battery unit monitoring module therein defining a module connection between said first battery unit monitoring module and said second battery unit monitoring module; and

a second data port connect to the input data port of said computing device;

wherein the first battery unit monitoring is a master to said second battery unit monitoring module and the second battery unit monitoring module is a slave to the first battery unit monitoring module,

wherein the first battery unit monitoring module responds to a data request signal from the output data request port of the computing device by transmitting data of the first battery unit to the input data port of the computing device and subsequently transmit a data request signal to the second battery unit monitoring module through said second output data request port;

wherein the second battery unit monitoring module responds to the data request from the second output data request port of the first battery unit monitoring module by transmitting data of the second battery unit to the input data port of the computing device;

wherein the computing device receives data from the first and second battery unit monitoring modules sequentially after sending a single data request signal to only the first battery unit monitoring module; and

wherein the computing device receives data from the second battery unit monitoring module automatically after receiving data from the first battery unit monitoring module; and

whereby the computing device is configured to shut off a battery charger when the computing device detects a high voltage condition from the first battery unit or the second battery unit.

20. A method of managing a battery comprising the steps of:

providing a battery management system comprising:

a computing device comprising:

an output data request port; and

an input data port;

a first battery unit monitoring module coupled with a first battery unit and comprising:

an input data request port connected to the output data request port of the computing device; and

an output data request port;

an output data port connected to the input data port of the computing device; and

a second battery unit monitoring module coupled with a second battery unit and comprising:

a single input data request port connected only to the output data request port of the first battery unit monitoring module, therein defining a module connection between said first battery unit monitoring module and said second battery unit monitoring module;

an output data port connected to the input data port of the computing device;

wherein the first battery unit monitoring is a master to said second battery unit monitoring module and the second battery unit monitoring module is a slave to the first battery unit monitoring module,

wherein the first battery unit monitoring module responds to a data request signal from the output data request port of the computing device by transmitting data of the first battery unit to the input data port of the computing device and subsequently transmits a data request to the second battery unit monitoring module through said module connection; and

wherein the second battery unit monitoring module responds to the data request from the output data request port the first battery unit monitoring module by transmitting data of the second battery unit to the input data port of the computing device;

transmitting, by the computing device, a first data request signal to the first battery unit monitoring module;

transmitting, by the first battery unit monitoring module, data of the first battery unit to the input data poet of the computing device in response to the first data request signal;

transmitting, by the first battery unit monitoring module, a second data request signal to the second battery unit monitoring module through the module connection between said first battery unit monitoring module and said second battery unit monitoring module, and

transmitting, by the second battery unit monitoring module, data of the second battery unit to the input data port of the computing device in response to the second data request signal;

wherein the computing device receives data from the first and second battery unit monitoring modules sequentially after sending a single data request signal to only the first battery unit monitoring module.