Patent ID: 8159188

Claim:
A method for managing power limits for a battery having a power capability that is a function of at least a state of charge (S.O.C.) of the battery, the battery further having a minimum operating S.O.C. and a discharge power limit that is a function of at least the S.O.C., an initial discharge power limit being set below an initial power capability such that a predefined full discharge power is available at states of charge above an initial minimum operating S.O.C., the method comprising: determining whether the full discharge power is available at the initial minimum operating S.O.C. after the power capability has decreased from the initial power capability; reducing the discharge power limit at a first predetermined S.O.C. to a first point below a present power capability curve; defining a first portion of a discharge power limit curve as containing the first point and being generally parallel to the present power capability curve over an S.O.C. range; and defining a second portion of the discharge power limit curve as having a generally constant power level above a second predetermined S.O.C.