*3.2. Exprimental Study*

The above model includes parameters that are related to battery SOH. In this study, we totally use thirteen 18650-type LiFePO4 lithium cells to conduct the aging tests, in which each cell is cycled to a different aging stage under room temperature. Then we test the cell characteristics under urban dynamometer driving schedule (UDDS) to provide dataset of the battery behaviors in different aging conditions. The UDDS voltage/current profile is provided in Section 5. In this section, we use the test data of four typical cells (denoted as No.1~4) to illustrate the method and propose the mathematical expression. The capacity and the corresponding SOH of these four cells are summarized in Table 1. The test battery parameters are given in Table 2.


**Table 1.** The aging conditions of the four cells.


**Table 2.** Specifications of the test cells.
