Patent ID: 9594121
Date: 2017-03-14
CPC Classifications: G01R

Claim:
1. A method of estimating a capacity of a battery pack, the method comprising: receiving, by battery control electronics associated with the battery pack from a voltage sensor configured to measure a terminal voltage of the battery pack, battery pack terminal voltage measurement information; calculating, by the battery control electronics, skewness information based on the battery pack terminal voltage measurement information, the skewness information defining a relationship between the battery pack terminal voltage measurement information and a plurality of states of charge of the battery pack; identifying, by the battery control electronics, a first inflection point in the skewness information; determining, by the battery control electronics, a first state of charge of the battery pack associated with the first inflection point; determining, by the battery control electronics, a second state of charge of the battery pack; determining, by the battery control electronics, a net charge difference of the battery pack between the first state of charge and the second state of charge; determining, by the battery control electronics, an estimated capacity of the battery pack based on the net charge difference, the first state of charge, and the second state of charge; and controlling, by the battery control electronics, an operation of the battery pack based on the estimated capacity of the battery pack, wherein the operation comprises at least one of a charging operation, a discharging operation, and a balancing operation.