avoinpiirijännitys

Avoinpilvijännitys, often translated as open-circuit voltage, refers to the maximum electrical potential difference a device, such as a solar cell or battery, can produce when no current is flowing. This occurs when the terminals of the device are not connected to any external circuit, hence the term "open circuit." In this state, the device's internal electromotive force (EMF) is directly measurable as the voltage across its terminals.

For solar cells, the open-circuit voltage (Voc) is a crucial parameter indicating the cell's performance potential. It is influenced by factors like the material's bandgap, temperature, and the intensity of incident light. Higher Voc generally suggests a more efficient conversion of light energy into electrical energy. However, Voc itself does not represent the power output of the cell, as power is the product of voltage and current.

Similarly, for batteries, open-circuit voltage is the voltage measured when the battery is disconnected from any load. This voltage reflects the battery's state of charge. As a battery discharges, its open-circuit voltage typically decreases. Monitoring Voc can provide an estimate of how much charge remains in the battery. It's important to note that Voc is a no-load condition, and the voltage under load will always be lower due to internal resistance.