A trickle charge or float charge is the charging method used to keep a battery at its full voltage. This method applies a voltage to the battery that is slightly higher than its self-discharge rate, which is typically between 13.4-13.8 volts for a 12-volt battery. Float charging is typically done when a battery is not in use and aims to maintain its charge, prevent internal corrosion, and maximize the battery's lifespan.
2. Bulk (Constant Current) Charge
Bulk charging is the first stage of charging a battery after it has been discharged. In this phase, a high current (typically 0.5C) is applied to quickly bring the battery voltage to its target voltage. During bulk charging, the current does not drop significantly, indicating the initial battery recovery from a discharged state.
3. Absorption Charge
The absorption charge follows the bulk charging phase and is characterized by a constant voltage applied to the battery. The voltage supplied during absorption charging is slightly lower than the bulk charge voltage, typically around 14.4-14.8 volts for a 12-volt battery. The absorption charge continues until the battery reaches a state of constant voltage, meaning that the battery voltage and charging current cease to rise despite sufficient time.
4. Equalization (Conditioning) Charge
Equalization charging aims to balance the charge levels of individual cells in a battery. It is designed to correct imbalances that may have arisen due to factors such as varying cell capacities, cell internal resistance, and temperature differences. During equalization, a higher voltage is applied to the battery, which enables even the weaker cells to reach a fully charged state. However, equalization charging requires regular monitoring and should not be performed frequently.
5. Pulse (Maintenance) Charge
Pulse charging is a battery maintenance technique used to extend battery life. It consists of alternating periods of applying small charging pulses to the battery and allowing it to rest. The pulses aim to prevent the battery from self-discharging and can also mitigate the issues related to sulfation within the battery.
