Patent Number: 8,796,993

Title: Historical analysis of battery cells for determining state of health

Abstract: 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.

Inventors: White; David Allen (Houston, TX), Benckenstein, Jr.; Claude Leonard (Stafford, TX)

Assignee: Southwest Electronic Energy Corporation

International Classification: H01M 10/44 (20060101)

Expiration Date: 8/05/12018