BATTERY LIFE ESTIMATION BASED ON VOLTAGE DEPLETION RATE

• US 20120277832A1
• Filed: 04/29/2011
• Published: 11/01/2012
• Est. Priority Date: 04/29/2011
• Status: Active Grant

• Current Assignee: LivaNova USA, Inc. (LivaNova Plc)
• Original Assignee: Cyberonics, Inc
• Inventors: Hussain, Saadat
• Granted Patent: US 8,761,885 B2
• Time in Patent Office: Days
• US Class Current: 607/62
• CPC Class Codes: A61N 1/37235 Aspects of the external programmer
• CPC Class Codes: A61N 1/378 Electrical supply
• CPC Class Codes: G01R 31/367 Software therefor, e.g. for battery testing using modelling or look-up tables
• CPC Class Codes: G01R 31/371 with remote indication, e.g. on external chargers
• CPC Class Codes: G01R 31/3835 involving only voltage measurements
• CPC Class Codes: G01R 31/392 Determining battery ageing or deterioration, e.g. state of health

Abstract

Apparatus and methods for estimating the remaining life of a battery in an implantable medical device (“IMD”) are disclosed herein. The terminal voltage of the battery is measured and the measurements create a baseline curve of the battery voltage depletion. The points along the baseline curve can be linearly extrapolated to calculate the voltage depletion rate, which can estimate the remaining life of the battery.

Claims

1. A method for managing a battery powering an implantable medical device (IMD), comprising:

taking a plurality of regular, periodic terminal voltage readings of the battery in the IMD; and

estimating future battery performance characteristics based upon a linear extrapolation from the plurality of voltage readings.

2. A method in accordance with claim 1, wherein the performance characteristics include at least one of time to depletion of the battery and time to end of service of the battery.

3. A method in accordance with claim 1, further comprising the steps of:

obtaining a baseline curve of voltage depletion over time for the battery in the IMD under selected operating parameters; and

making a first estimate of future battery performance characteristics based upon a linear extrapolation from the plurality of voltage readings and an initial point of the baseline curve.

4. A method in accordance with claim 3, further comprising the step of modifying the baseline curve based upon a change of the operating parameters of the IMD.

5. A method in accordance with claim 1, further comprising the step of wirelessly transmitting data representing the detected terminal voltage of the battery from the IMD to a remote computing device.

6. A method in accordance with claim 5, wherein the IMD is an implantable pulse generator for vagus nerve stimulation.

7. A method in accordance with claim 5, wherein the step of taking the plurality of regular, periodic terminal voltage readings is performed by the IMD;

and the step of estimating future battery performance characteristics is performed by the remote computing device.

8. A method in accordance with claim 5, wherein the remote computing device is selected from the group consisting of a PDA, a smartphone, a laptop computer, and a special purpose portable computing device.

9. A method in accordance with claim 1, further comprising the step of providing to a user of the IMD an indication of the future battery performance characteristics.

10. A method in accordance with claim 9, wherein the indication is selected from the group consisting of an indicator light, an alphanumeric display, an iconic indicator, and an audible indicator.

11. A method for estimating a life of a battery in an implantable medical device (IMD), comprising:

obtaining a baseline curve of voltage depletion over time for the battery in the IMD under selected operating parameters;

taking a first reading and subsequent readings of battery terminal voltage at regular intervals;

making a first battery life estimate based upon a linear extrapolation from the first voltage reading and the baseline curve; and

making subsequent battery life estimates based upon a linear extrapolation of the subsequent voltage readings.

12. A method in accordance with claim 11, wherein the battery life estimate includes at least one of time to depletion of the battery and time to end of service of the battery.

13. A method in accordance with claim 11, wherein the regular interval is about once per day.

14. A method in accordance with claim 11, further comprising the step of providing to a user an indication of the first or subsequent battery life estimates using an indicator selected from the group consisting of an indicator light, an alphanumeric display, an iconic indicator, and an audible indicator.

15. A method in accordance with claim 11, further comprising the step of wirelessly transmitting data representing the voltage readings from the IMD to a remote computing device, and the steps of taking first and subsequent readings of battery terminal voltage are performed by the IMD;

and the steps of making the first and subsequent battery life estimates are performed by the remote computing device.

16. A method in accordance with claim 15, wherein the remote computing device is selected from the group consisting of a PDA, a smartphone, a laptop computer, and a special purpose portable computing device.

17. An implantable system, comprising:

an implantable device, having a microprocessor and system memory, a battery, and a battery circuit capable of measuring battery terminal voltage;

an external computing device, having a microprocessor and system memory; and

a computer program product, stored in the system memory of at least one of the implantable device and the external device, comprising machine-readable instructions for;

periodically measuring terminal voltage of the battery; and

estimating a life of the battery based upon a linear extrapolation from the plurality of the periodic voltage measurements.

18. A system in accordance with claim 17, wherein the system memory includes data representing a baseline curve of voltage depletion over time for the battery in the implantable device under selected operating parameters, and the computer program product includes instructions for making a first estimate of the life of the battery based upon the baseline curve and a first of the periodic voltage measurements.

19. A system in accordance with claim 17, wherein the implantable device further comprises a wireless transmitter, and programming instructions only for periodically measuring terminal voltage of the battery and transmitting data representative thereof to the external device.

20. A system in accordance with claim 17, wherein the external device is selected from the group consisting of a PDA, a smartphone, a laptop computer, and a special purpose portable computing device.

21. A system in accordance with claim 17, wherein the external device includes an indicator mechanism selected from the group consisting of an indicator light, an alphanumeric display, an iconic indicator, and an audible indicator, the indicator mechanism being configured to providing to a an indication of the battery life estimate.