Battery montoring apparatus and daisy chain interface suitable for use in a battery monitoring apparatus

• US 20080180106A1
• Filed: 01/28/2008
• Published: 07/31/2008
• Est. Priority Date: 01/31/2007
• Status: Active Grant

• Current Assignee: Analog Devices, Inc.
• Original Assignee: Analog Devices, Inc.
• Inventors: Gorbold, Jeremy Richard
• Granted Patent: US 7,859,223 B2
• Time in Patent Office: Days
• US Class Current: 324/434
• CPC Class Codes: G01R 31/3648 comprising digital calculation means, e.g. for performing an algorithm
• CPC Class Codes: G01R 31/396 Acquisition or processing of data for testing or for monitoring individual cells or groups of cells within a battery

Abstract

A battery monitor for monitoring the performance of at least one battery within an array of batteries, comprising: a data acquisition device for measuring at least one parameter of the at least one battery associated with the battery monitor, a first data interface operable to exchange data with a first device, and a second data interface operable to exchange data with a second device.

Claims

1. A battery monitor for monitoring the performance of at least one battery within an array of batteries, comprising:

a data acquisition device for measuring at least one parameter of the at least one battery associated with the battery monitor,

a first data interface operable to exchange data with a first device, and

a second data interface operable to exchange data with a second device.

2. A battery monitor as claimed in claim 1, in which the battery monitor has first and second power connections to at least one battery that it is monitoring, such that the supply voltages of the battery monitor float with respect to a ground voltage.

3. A battery monitor as claimed in claim 2, in which the supply voltages of a battery monitor may differ from those of neighbouring devices.

4. A battery monitor as claimed in claim 1, in which first data interface has a transmit output for sending data to the first device.

5. A battery monitor as claimed in claim 4, in which the first data interface modulates a current exchanged between the battery monitor and the first device so as to transmit data to the further device.

6. A battery monitor as claimed in claim 1, in which the first data interface has a received input for receiving data from the first device.

7. A battery monitor as claimed in claim 6, in which the first data interface is responsive to changes in current exchanged between the battery monitor and the first device so as to receive data from the first device.

8. A battery monitor as claimed in claim 1, in which the first data interface transmits data by modulating a voltage at an output thereof and is responsive to a voltage charges at an input thereof.

9. A battery monitor as claimed in claim 1, in which the first interface further has a clock input for receiving a clock signal.

10. A battery monitor as claimed in claim 1, in which the second data interface has transmit output for sending data to the second device and an input for receiving data from the second device.

11. A battery monitor as claimed in claim 10, in which the second interface modulates a current exchange with the second device to transmit data to the second device and is responsive to changes in current exchanged with the second device to receive data.

12. A battery monitor as claimed in claim 1, in which the second data interface has a clock output for outputting a clock signal.

13. A battery monitor as claimed in claim 1, further including a memory for buffering data such that data received at the second data interface can be stored prior to retransmission via the first interface.

14. A battery monitor as claimed in claim 1, further including a memory for buffering data such that data received at the first data interface can be stored prior to retransmission via the second interface.

15. A battery monitor as claimed in claim 1, in which the battery monitor measures at least one of a voltage occurring across a plurality of battery cells, a voltage occurring across each battery cell within a plurality of battery cells and temperature of at least one battery cell.

16. A battery monitoring system comprising a plurality of battery monitors as claimed in claim 1, the monitors arranged in series such that the second data interface of an (j−

i)th battery monitor is in communication with the first interface of a jth battery monitor, where j is an integer greater than one.

17. A battery monitoring system as claimed in claim 16, where the second data interface of the jth battery monitor is connected to the first data interface of a (j+1)th battery monitor.

18. A battery monitoring system as claimed in claim 16, wherein each battery monitor is individually addressable.

19. An interface for devices arranged, in use, to be connected in a daisy chain, the interface comprising an output path wherein a signal to be transmitted is used to modulate a current source, and an input path where a modulated current flowing in the input path is detected so as to recover data.

20. An interface as claimed in claim 19, further including a clock path, wherein the clock signal is passed as a modulated current.