What Causes the Acidification and Ageing of EVA Photovoltaic Films and What Effects Does It Have?

The encapsulation and protection of solar cells is provided by photovoltaic films made of ethylene-vinyl acetate (EVA), which are essential components of solar panels. However, over the course of time, these films may undergo ageing and acidification, which can result in a decline in their performance and ability to function efficiently. In this article, we investigate the phenomenon of ageing and acidification in EVA photovoltaic films, looking at the factors that contribute to this process as well as the consequences that it has.

The Factors That Cause UV Exposure: Ageing and Acidification One of the key factors that contributes to the ageing process of EVA photovoltaic films is their continuous exposure to ultraviolet (UV) radiation from the sun. The polymer chains in EVA are broken down by ultraviolet radiation, which results in a decrease in the material’s mechanical strength and an increase in its susceptibility to acidity.

Infiltration of Moisture: The process of ageing can be sped up by the introduction of moisture into the structure of the solar panel. It is possible for impurities and pollutants to react with moisture that has penetrated the EVA coating, resulting in the formation of acids that contribute to the acidification process.

Temperature changes: Extreme temperature changes, particularly in places that experience hot summers and freezing winters, can hasten the ageing process of EVA films. Thermal stress induces expansion and contraction, which ultimately results in the formation of microcracks and an increase in the material’s permeability to acids and moisture.

acidity can be caused by chemical impurities, such as pollutants in the air or off-gassing from other materials in the solar panel assembly. These chemical contaminants can react with EVA and contribute to the acidity of the environment.

Incomplete Cross-Linking: If the cross-linking of EVA is not completed during the production process, it may lead to the formation of residual unreacted components that are prone to deterioration over the course of time.

Effects of Acidification and the Ageing Process

Transparency Loss: As EVA photovoltaic films age, they may become hazy or yellowed, which reduces their transparency. This might happen because of the ageing process. As a result, the amount of light that is transmitted to the solar cells may decrease, which will have an effect on the efficiency of the panel.

Reduced Mechanical Strength: As EVA films age, they endure a loss in their mechanical strength, which causes them to become more brittle and more susceptible to cracking. The structural integrity of the solar panel is compromised as a result of this decision.

Potential-Induced Degradation (PID): Acidification of EVA films can be a contributor to PID, which is a phenomenon in which a voltage potential between the solar cells and the grounded frame of a PV module causes power degradation over time. Significant amounts of energy can be lost as a result of PID.

Delamination: The link between the EVA film and the solar cells or glass might get weaker over time due to acidification and ageing, which can result in delamination. In the process of delamination, moisture and pollutants are able to infiltrate the panel, which makes the degradation process even more dramatic.

Acidification can degrade the electrical insulation qualities of EVA, which can increase the chance of electrical faults or short circuits occurring within the solar panel. This can lead to a loss of electrical insulation.

Preventative measures and mitigation

Proper Encapsulation: It is crucial for the longevity and performance of solar cells to ensure that they are encapsulated with high-quality EVA films in the correct manner during the production process.

UV Stabilisers: The incorporation of UV stabilisers into EVA formulations facilitates the protection of the material against degradation caused by ultraviolet light.

Barrier against Moisture: The installation of efficient moisture barriers inside the framework of the solar panel can prevent the infiltration of moisture and the consequent acidification of the panel.

In order to reduce thermal stress and slow down the ageing process, it is important to maintain appropriate temperatures within the solar panel. This can be accomplished by maintaining consistent and optimal temperatures.

Performing Routine Inspections and Maintenance: Solar panels should be inspected on a regular basis to identify any signs of ageing, such as yellowing or delamination, so that they may be replaced or repaired in a timely manner.

The use of anti-aging chemicals into EVA formulations is a practice that is utilised by certain manufacturers in order to improve the material’s resilience to the effects of ageing and acidity.

Over the course of their operating lifetimes, EVA photovoltaic films are subjected to a number of important difficulties, including acidity and ageing. Key elements that contribute to these difficulties include exposure to ultraviolet light, the introduction of moisture, variations in temperature, the presence of chemical pollutants, and insufficient cross-linking. Reduced transparency, loss of mechanical strength, PID, delamination, and poor electrical insulation are some of the impacts that might occur as a result of ageing and acidity. For the purpose of preserving the performance and longevity of EVA photovoltaic films in solar panel applications, it is essential to implement mitigation methods such as correct encapsulation, UV stabilisers, moisture barriers, temperature control, frequent maintenance, and anti-aging additives. By gaining an understanding of these processes, it is possible to take preventative actions to lessen the influence they have and to guarantee the effectiveness and dependability of solar energy systems.

COACE’s RM211A is an anti-acidification additive for EVA amination. It is mainly used for EVA photovoltaic films. It can well improve the aging resistance and anti-acidification properties of EVA films under high and gradually high humidity conditions. Extend the service life of photovoltaic film!