This document describes a simplified Simulink model of a lead-acid battery that can be used to simulate charge and discharge characteristics. The model accounts for battery voltage (Vbat) versus state of charge (SOC) and can simulate charge/discharge times at various current rates. It includes example simulations for a 50Ah battery showing charge time, discharge time waves at different discharge rates, and Vbat vs SOC curves. Instructions are provided on adjusting the model for different battery specifications by editing parameters like capacity and number of cells.