This charge curve of a Lithium-ion cell plots various parameters such as voltage, charging time, charging current and charged capacity. When the cells are assembled as a battery pack for an application, they must be charged using a constant current and constant voltage (CC-CV) method.
Firstly, the similarity of the charging voltage curves of the single cells within the battery pack is discussed with the help of the battery equivalent model and the aging test data. Ideally, the decline in battery capacity is reflected in the horizontal linear shrinkage of the charging voltage curve.
The lithium battery charging curve illustrates how the battery’s voltage and current change during the charging process. Typically, it consists of several distinct phases: Constant Current (CC) Phase: In this initial phase, the charger applies a constant current to the battery until it reaches a predetermined voltage threshold.
The working voltage of the battery is used as the ordinate, discharge time, or capacity, or state of charge (SOC), or discharge depth (DOD) as the abscissa, and the curve drawn is called the discharge curve. To understand the discharge characteristic curve of a battery, we first need to understand the voltage of the battery in principle.
The charge curve of a battery depends on the chemistry of battery electrodes, the charging current, and the health status of the battery. As the first two parameters are known and measurable in real applications, quantifying the aging mechanisms, i.e., health status, of the battery is crucial for accurately predicting the charge curve.
Therefore, the charge curve is important for understanding the status of a battery. The charge curve of a battery depends on the chemistry of battery electrodes, the charging current, and the health status of the battery.