Patent ID: 6731096
Filing Date: 2004-05-04
Classification: H02J

Abstract:
A method or charging a battery, the method comprising the steps of:a. providing a rechargeable battery cell; b. providing a charger; c. recognizing at least one battery characteristic; d. testing the battery; e. reading a first temperature; f. comparing the first temperature to a threshold; g. entering a charge mode for a predetermined time; h. reading a voltage, comparing the read voltage to a predetermined threshold voltage, and entering a second charge mode where the read voltage exceeds the predetermined threshold voltage; i. reading a second temperature at the end of the predetermined time; j. calculating a difference between the second temperature and the first temperature divided by the predetermined time; k. comparing the difference between the second temperature and the first temperature divided by the predetermined time to a predetermined (dT/dt value; and l. reducing charging current when the difference between the second temperature and the first temperature divided by the predetermined time exceeds the predetermined dT/dt value.