Blocking diodes play a pivotal role in protecting your solar panels and batteries. They ensure that the power flows in one direction – from the solar panel to the battery – and prevent the reverse flow, which could drain the battery at night or during cloudy days. Prevents batteries from discharging through solar cells at night.
In short, as diode only passes current in one direction, so the current from solar panels flows (forward biased) to the battery and blocks from the battery to the solar panel (reverse biased). What is a Diode?
To overcome this issue, blocking diodes are used to block the current flow back to the solar panels which prevents the draining of battery as well as protect the solar cells from hot-spots due to dissipating power inside it which lead to damage the solar cell.
The advantage of this is that diodes can be used to block the flow of electric current from other parts of an electrical solar circuit. When used with a photovoltaic solar panel, these types of silicon diodes are generally referred to as Blocking Diodes.
Third, bypass diodes provide alternative routes around solar cells that aren’t generating current. If a cell is shaded or damaged, its diode will send current around it, preventing losses. Fourth, blocking diodes stop reverse current flow from the battery to the solar panel at night, preventing power drainage.
Choose a diode with twice the current and voltage rating of your system’s maximum measurement. For example, for 10 Amps, use a 20 Amp diode. 3. Why does my solar panel drain the battery at night? If the battery drains at night, it could be due to a malfunctioning Solar Charge Controller, which fails to prevent reverse power flow back to the panel.