Method for monitoring end of life for battery
US7515962B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Oct 7, 2003 |
| Grant date | Apr 7, 2009 |
| Priority date | — |
| Expiry date | Oct 6, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02J2310/23
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A system is described which has a battery, a device which is powered by the battery in an episodic manner, and a charge storage capacitor. The system has attached to the charge storage capacitor a device or devices capable of: reading the rate of charge storage; or measuring both time and charge stored or added to the charge storage capacitor so that a rate of charge storage may be calculated. The estimated replacement time for the battery, particularly for a lithium battery in a pacing device, is easily estimated. Also described herein is a process for estimating a level of energy depletion in the system. The process comprises: finding a relatively quiescent period in powering of the device in the episodic manner; determining a rate of charging in the storage capacitor during the quiescent period; and correlating the rate of charging in the storage capacitor to a value of internal impedance in the battery through a comparison with known relationships for the battery and rate of charging to determine a value for the internal impedance of the battery.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.