Crystal G
8 minutes
ISOS Stability Testing Protocols for Perovskite Solar Cells
ISOS stability testing protocols are an agreed set of stress tests for perovskite and other new solar cells. They exist so that labs can compare results fairly. Each test has a letter for the stress. D is dark storage, which tests heat and humidity without light. L is light soaking under a lamp. O is outdoor testing in real weather. T is thermal cycling between hot and cold. LC is light cycling, on and off like day and night. V applies an electrical bias in the dark. Each test also has a level from 1 to 3. Level 1 is a simple lab setup, and level 3 adds tight control of temperature and humidity. A result reads like a label, so ISOS-L-2 means light soaking at level 2. The protocols also say what a report must state: temperature, humidity, light source, and whether the cell was encapsulated. Load matters too. A cell held at its maximum power point ages differently from one left at open circuit. Light cycling can be harsher than steady light, because ions move in the light and drift back in the dark. Pick the test that matches the failure you care about. Light soaking alone will not show water ingress. After this Concept you can decode an ISOS label and say which stress a stability result did and did not test.