Method for determining state of charge in lithium batteries through use of a novel electrode

Abstract

The accurate determination of the state-of-charge (SOC) of batteries is an important element of battery management. One method to determine SOC is to measure the voltage of the cell and exploiting the correlation between voltage and SOC. For electrodes with sloped charge/discharge profiles, this is a good method. However, for batteries with lithium iron phosphate (LFP) cathodes the charge/discharge profile is flat. Now, by using the materials and methods disclosed herein, an amount of cathode active material that has a sloped charge/discharge profile is mixed with LFP in a cathode, which results in a charge/discharge profile with enough slope that the SOC of the battery can be determined by measuring the voltage alone.

Dependencies are inferred from the claim text.