Apple Inc.
ASYMMETRIC BATTERY PACK WITH VARIED ELECTRODE AND CURRENT COLLECTOR PROPERTIES TO ACHIEVE C-RATE BALANCING

Abstract:

The disclosed technology relates to battery packs having battery cells of different designs or capacities with an imbalance in the charging and/or discharging current supplied to and provided by each jelly roll due to differences in capacity specific impedance between the battery cells of a battery pack. The battery pack includes at least a first and second battery cell connected in parallel, with a thickness of an active layer and/or current collector of a battery cell having an altered thickness to reduce an impedance of the battery cell.