Why should a series diode be connected between a solar panel and a storage battery that is being charged by the panel?
To prevent overload by regulating the charging voltage
To prevent discharge of the battery through the panel during times of low or no illumination✓Correct answer
To limit the current flowing from the panel to a safe value
To prevent damage to the battery due to excessive voltage at high illumination levels
Explanation
In darkness the battery voltage exceeds the panel voltage, so without a blocking element current would flow backwards from the battery through the panel and discharge it. A series diode conducts only in the charging direction, so reverse current is blocked.