Method and device for detecting early battery depletion condition

Patent metadata

Field	Value
Publication number	US-11221373-B2
Application number	US-201715631184-A
Country	US
Kind code	B2
Filing date	Jun 23, 2017
Priority date	Jun 23, 2017
Publication date	Jan 11, 2022
Grant date	Jan 11, 2022

Abstract

Methods, devices and program products are provided for determining an early battery depletion condition for a battery powered device. The method determines a charge consumption drawn externally from a battery cell by the device for a select period of time, obtains a measured cell voltage for the battery cell of the medical device, calculates a projected cell voltage based on the charge consumption and usage conditions, and declares an early depletion condition based on a relation between the measured and projected cell voltages.

First claim

What is claimed is:

1. A computer implemented method to determine an early battery depletion condition for a battery powered device, the method comprising:
under control of one or more processors of the battery powered device, where the one or more processors are configured with specific executable instructions,
determining a charge consumption drawn externally from a battery cell by the battery powered device for a select period of time;
obtaining a measured cell voltage for the battery cell of the battery powered device;
calculating a projected cell voltage based on the charge consumption; and
declaring an early depletion condition based on a relation between the measured and projected cell voltages.

2. The method of claim 1 , wherein the declaring operation comprises identifying a divergence characteristic, between the measured and projected cell voltages, that is indicative of internal battery cell self-discharge.

3. The method of claim 1 , further comprising declaring a no early depletion condition when the measured and projected cell voltages fall with a tolerance range of one another.

4. The method claim 1 , further comprising obtaining a steady state charge consumption and a task related charge consumption from the battery cell for the select period of time, the steady state and task related charge consumptions included within the charge consumption.

5. The method of claim 1 , further comprising recalibrating at least one of the projected cell voltage or charge consumption based on the measured cell voltage when a select criteria is maintained for a predetermined period of time.

6. The method of claim 5 , wherein the recalibration operation occurs when the predetermined period of time passes without a capacitor discharge task occurring.

7. The method of claim 1 , wherein the calculation operation includes utilizing at least one of a i) a voltage versus capacity curve associated with the battery cell; ii) a predetermined functional relation between voltage and charge capacity, or iii) an initial cell voltage, a cell voltage rate of change and the charge consumption for the period of time.

8. The method of claim 1 , wherein the estimating operation comprises obtaining an average charge consumption drained from the battery cell, and estimating the charge consumption based on the average charge consumption over a period of time.

9. The method of claim 1 , further comprising, during a transient recovery interval following a capacitor discharge task, calculating a projected transient voltage and utilizing the projected transient voltage to calculate the projected cell voltage.

10. The method of claim 1 , wherein the obtaining operation includes obtaining a plurality of the measured cell voltages and based thereon, determining current and past measured rates of change for cell voltages, wherein the past measured rate of change corresponds to a past period of time, the current measured rate of change corresponding to a current period of time, the declaring operation including comparing the current and past measured rates of change to determine whether a difference there between exceeds a predetermined factor.

11. The method of claim 1 , wherein the charge consumption corresponds to a steady state charge consumption over the period of time, the total steady state charge consumption obtained by integrating current from steady state power usage.

12. The method of claim 1 , wherein the charge consumption corresponds to task related charge consumption for one or more tasks that are tracked by the device, the task related charge consumption obtained by multiplying the corresponding average current draw during a task times the time spent performing the task, and summing the task related charge consumption for the one or more tasks.

13. The method of claim 1 , wherein the determining the charge consumption is performed while the device is operating for the select period of time.

14. A system to determine an early battery depletion condition for a battery powered medical device, the system comprising:
a processor;
memory storing program instructions accessible by the processor;
wherein, responsive to execution of the program instructions, the processor:
determine a charge consumption drawn externally from a battery cell by a medical device for a select period of time;
obtains a measured cell voltage for the battery cell of the medical device;
calculates a projected cell voltage based on the charge consumption; and
declares an early depletion condition based on a relation between the measured and projected cell voltages.

15. The system of claim 14 , further comprising a housing for the medical device that includes the processor and memory such that the processor of the medical device declares the early depletion condition.

16. The system of claim 14 , further comprising an external device to communicate with the medical device, the medical device including a measuring circuit to measure the cell voltage, the medical device including a transmitter to transmit the measured cell voltage to the external device, the external device including the memory and processor to perform the estimating, obtaining, calculating and declaring operations.

17. The system of claim 14 , further comprising an external device to communicate with the medical device, the medical device and the external device including first and second processors, respectively, to share the estimating, obtaining, calculating and declaring operations.

18. The system of claim 14 , wherein the processor is configured to declare a no early depletion condition when the measured and projected cell voltages fall with a tolerance range of one another.

19. The system of claim 14 , wherein the processor is configured to declare recalibrate at least one of the projected cell voltage or charge consumption based on the measured cell voltage when a select criteria is maintained for a predetermined period of time.

20. The system of claim 14 , wherein the calculation operation includes utilizing at least one of a i) a voltage versus capacity curve associated with the battery cell; ii) a predetermined functional relation between voltage and charge capacity, or iii) an initial cell voltage, a cell voltage rate of change and the charge consumption for the period of time.

21. The system of claim 14 , wherein the estimating operation comprises obtaining an average charge consumption drained from the battery cell, and estimating the charge consumption based on the average charge consumption over a period of time.

22. The system of claim 14 , wherein the processor is configured to, during a transient recovery interval following a capacitor discharge task, calculate a projected transient voltage and utilizing the projected transient voltage to calculate the projected cell voltage.

23. The system of claim 14 , wherein the charge consumption corresponds to a steady state charge consumption over the period of time, the total steady state charge consumption obtained by integrating current from steady state power usage.

24. The system of claim 14 , wherein the charge consumption corresponds to task related charge consumption for one or more tasks that are tracked by the device, the task related charge consumption obtained by multiplying the corresponding average current draw during a task times the time spent performing the task, and summing the task related charge consumption for the one or more tasks.

Assignees

• Pacesetter Inc

Inventors

• Fischer Avi
• Bornzin Gene A
• Strange Thomas F
• Pei Xing
• Goil Aditya
• Dawoud Fady
• Ryu Kyungmoo
• Beauvais Joseph
• Mouchawar Gabriel
• Williamson Richard

Classifications

• H02J7/82

  Control of state of charge [SOC] · CPC title

• H01M10/48

  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 title

• A61N1/3708 Primary

  for power depletion · CPC title

• G01R31/392 Primary

  Determining battery ageing or deterioration, e.g. state of health · CPC title

• H01M10/4285

  Testing apparatus · CPC title