Method and apparatus for determining the state-of-charge of batteries particularly lithium batteries
Patent 4725784 Issued on February 16, 1988. Estimated Expiration Date: 
February 16, 2005. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
February 16, 2005. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesDevice for controlling the charging and discharging of a storage battery System for measuring state of charge of storage battery Quiescent voltage sampling battery state of charge meter Battery state of charge evaluator Patent #: 4558281 InventorsApplicationNo. 06/648943 filed on 09/10/1984US Classes:324/427, To determine ampere-hour charge capacity320/149, With detection of current or voltage integral (e.g., total charge, etc.)320/150, With thermal condition detection320/162, With detection of current or voltage amplitude340/636.15By voltageExaminersPrimary: Eisenzopf, Reinhard J.Assistant: Mueller, Robert W. Attorney, Agent or FirmInternational ClassG01R 31/36 (20060101)Foreign Application Priority Data1983-09-16 ILAbstractMethod and apparatus for determining the state-of-charge of batteries, particularly lithium batteries, involves the steps of: (a) measuring the temperature of the battery; (b) loading the battery to produce a high discharge for a short period of time; (c) after a short rest period, measuring the open-circuit-voltage of the battery; and (d) determining from the measured temperature and open-circuit-voltage the residual state-of-charge of the battery. Preferably, the residual state-of-charge of the battery is determined by comparing the measured temperature and open-circuit-voltage with reference tables showing the state-of-charge at different temperatures and open-circuit-voltages for the respective battery. | |
