Determining and forecasting end of life for an implantable medical device having a rechargeable battery
First Claim
1. Circuitry for a medical device, comprising:
- a rechargeable battery;
control circuitry configured to configured to implement an algorithm, wherein the algorithm is configured to;
estimate a capacity of the battery at different points in time during operation of the medical device,store the estimated capacities and their associated times in the medical device, andforecast and/or determine an end of life of the medical device by deriving a function of battery capacity versus time using the stored estimated capacities and their associated times.
1 Assignment
0 Petitions
Accused Products
Abstract
An algorithm programmed into the control circuitry of a rechargeable-battery Implantable Medical Device (IMD) is disclosed that can quantitatively forecast and determine the timing of an early replacement indicator (tEOLi) and an IMD End of Life (tEOL). These forecasts and determinations of tEOLi and tEOL occur in accordance with one or more parameters having an effect on rechargeable battery capacity, such as number of charging cycles, charging current, discharge depth, load current, and battery calendar age. The algorithm consults such parameters as stored over the history of the operation of the IMD in a parameter log, and in conjunction with a battery capacity database reflective of the effect of these parameters on battery capacity, determines and forecasts tEOLi and tEOL Such forecasted or determined values may also be used by a shutdown algorithm to suspend therapeutic operation of the IMD.
20 Citations
27 Claims
-
1. Circuitry for a medical device, comprising:
-
a rechargeable battery; control circuitry configured to configured to implement an algorithm, wherein the algorithm is configured to; estimate a capacity of the battery at different points in time during operation of the medical device, store the estimated capacities and their associated times in the medical device, and forecast and/or determine an end of life of the medical device by deriving a function of battery capacity versus time using the stored estimated capacities and their associated times. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16)
-
-
17. A method for operating a medical device having a rechargeable battery, comprising:
-
estimating and storing in the medical device a capacity of the rechargeable battery of the medical device as a function of time during operation of the medical device, and forecasting and/or determining an end of life of the medical device by extrapolating from the capacity as a function of time a time at which the capacity equals a capacity threshold.
-
-
18. Circuitry for a medical device, comprising:
-
a rechargeable battery; a first register configured to store a shutdown time at which therapeutic operation of the medical device will be suspended; control circuitry configured to configured to implement an algorithm, wherein the algorithm is configured to; determine an end of life of the medical device using at least a first estimated capacity of the battery; and suspend therapeutic operation of the medical device even if the shutdown time has not been reached. - View Dependent Claims (19, 20, 21, 22, 23)
-
-
24. Circuitry for a medical device, comprising:
-
a rechargeable battery; a first register configured to store a shutdown time at which therapeutic operation of the medical device will be suspended; control circuitry configured to configured to implement an algorithm, wherein the algorithm is configured to; forecast an end of life of the medical device using at least a first estimated capacity of the battery; determine that the shutdown time has been reached; continue therapeutic operation of the medical device if the forecasted end of life is greater than the shutdown time; and suspend therapeutic operation of the medical device if the determined end of life is not greater than the shutdown time. - View Dependent Claims (25, 26, 27)
-
Specification