Historical analysis of battery cells for determining state of health

摘要

Battery cells may be monitored and a historical profile of the battery generated. The historical profile may be used to analyze a state-of-health of the battery cell. For example, the historical profile may be used to determine when a battery cell has developed an internal short that creates a safety hazard. The historical profile may include a count of the number of times the battery cell was out of balance and a count of the number of Coulombs the battery cell was out of balance. The number of Coulombs may be counted for a window of time. When the number of Coulombs exceeds a Coulomb threshold, a state-of-health flag may be set for the battery cell. The Coulomb threshold may be adjusted based, in part, on the counted number of times the battery cell is out of balance.

主权项

1. A method, comprising:
counting the number of times a battery cell of an array of battery cells is out of balance with other battery cells; determining a Coulomb threshold level based, in part, on the counted number of times; counting a number of Coulombs the battery cell is out of balance with the other battery cells; and setting a state-of-health flag when the counted number of Coulombs exceeds the Coulomb threshold level.