Battery monitoring system with integrated battery holder

• US 20010005123A1
• Filed: 01/31/2001
• Published: 06/28/2001
• Est. Priority Date: 07/22/1999
• Status: Active Grant

• Current Assignee: Maxim Integrated Products, Inc. (Analog Devices, Inc.)
• Original Assignee: Brian W. Jones, Scott L. Jones
• Inventors: Jones, Brian W., Jones, Scott E.
• Granted Patent: US 6,351,099 B2
• Time in Patent Office: Days
• US Class Current: 320/107
• CPC Class Codes: G01R 19/16542 for batteries charge condition monitoring in G01R31/36
• CPC Class Codes: G01R 31/3647 for determining the ability of a battery to perform a critical function, e.g. cranking
• CPC Class Codes: G01R 31/3648 comprising digital calculation means, e.g. for performing an algorithm
• CPC Class Codes: G01R 31/367 Software therefor, e.g. for battery testing using modelling or look-up tables
• CPC Class Codes: H01M 10/4257 Smart batteries, e.g. electronic circuits inside the housing of the cells or batteries
• CPC Class Codes: H01M 10/48 Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals, H01M50/569
• CPC Class Codes: H01M 50/216 adapted for button or coin cells
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y10S 320/12 Precharging analysis, e.g. determining presence of battery

Abstract

An apparatus for monitoring the condition of a battery. The apparatus includes a battery clip that is used to secure a battery to a battery connection and a battery monitoring IC. The battery monitoring IC takes a “load vs. no-load measurement” and the results are recorded in a register. When the battery reaches a certain low voltage state, register bits are set and an output is generated. Furthermore, the exemplary embodiment includes a removal detection circuit for detecting removal and replacement of the battery and for preventing voltage floating on the battery output line.

Claims

1. A battery monitoring system for monitoring the state of a battery, the system comprising:

a printed circuit board (PCB);

an electrical contact connected to the PCB, the electrical contact for electrically coupling with the battery;

a battery monitoring integrated circuit (IC) attached to the PCB, the battery monitoring IC for determining the state of the battery; and

a battery clip attachable to the PCB, the battery clip, when attached to the PCB, for securing the battery to the electrical contact.

2. The battery monitoring system of

claim 1

, wherein the battery monitoring IC comprises:

measurement circuitry for performing a DELTA-V measurement.

3. The battery monitoring system of

claim 2

, wherein the battery monitoring IC further comprises:

a storage location for storing the DELTA-V measurement.

4. The battery monitoring system of

claim 3

, wherein the battery monitoring IC further comprises:

an interface connected to the storage location, the DELTA-V measurement stored in the storage location being accessible through the interface.

5. The battery monitoring system of

claim 2

, further comprising:

circuitry for signaling a low battery condition.

6. The battery monitoring system of

claim 5

, further comprising:

a storage device connected to the circuitry;

wherein an indicator of the low battery condition is stored in the storage device.

7. The battery monitoring system of

claim 1

, wherein the battery monitoring IC comprises:

a battery removal detector for detecting the removal of the battery from the electrical contact.

8. The battery monitoring system of

claim 7

, wherein the battery removal detector limits voltage floating on a battery output line responsive to the battery being removed from the electrical contact.

9. The battery monitoring system of

claim 1

, wherein the battery clip is configured to secure a coin-shaped primary cell.

10. A battery monitoring circuit comprising:

a measurement circuit element for performing a DELTA-V measurement;

a storage device for storing the DELTA-V measurement; and

an interface connected to the storage location, the DELTA-V measurement stored in the storage device being accessible through the interface; and

a signal circuit element for signaling a low battery condition responsive to the DELTA-V measurement.

11. The battery monitoring circuit of

claim 10

wherein an indicator of a low battery is stored in the storage device.

12. The battery monitoring circuit of

claim 10

, wherein the battery monitoring IC comprises:

a battery removal detector for detecting removal of the battery.

13. The battery monitoring circuit of

claim 12

, wherein the battery removal detector limits voltage float on a battery output line.

14. The battery monitoring circuit of

claim 10

further comprising:

a primary cell coupled with the measurement circuit element.

15. A system comprising:

a memory device for storing data, the memory device configured to draw power from a primary power source and a battery;

a battery holder connected to the memory device, the battery holder for holding the battery; and

a controller attached to the battery holder, the controller for monitoring the condition of the battery and for generating a low battery indication.

16. The system of

claim 15

wherein the controller performs a DELTA-V measurement.

17. The system of

claim 16

further comprising:

a storage device connected to the controller, the storage device for storing the low battery indication.

18. The system of

claim 17

further comprising:

a processor connected to the storage device, the processor for receiving the low battery indication.

19. The system of

claim 18

wherein the low battery indication is generated prior to battery failure.

20. The system of

claim 15

wherein the battery holder is attachable to a system board.