Since photovoltaic power generation has entered the large-scale power station level application, in order to further reduce production costs and improve scale production, the size of battery chips launched on the market has become larger and larger, from the early 125mm*125mm to more than 210mm*210mm. The battery cells used are getting larger and larger. The power of the basic power generation unit components of the photovoltaic system has also increased from 100W+, and the photovoltaic components have reached more than 700W+. At the same time, the weight of the component is nearly 35Kg, and the unit weight has also increased to 12.4kg/square meter. Considering the installation bracket and other 3-6Kg/square meter, the unit weight is about 16Kg/square meter. This is difficult for some large-span industrial buildings, including industrial plants, to bear. In this way, some large roofs with actual load-bearing restrictions make it impossible to install and apply such photovoltaic components. How to reduce the weight of photovoltaic components and enable photovoltaics to adapt to more application scenarios has become a bottleneck for the further development of the industry.
How to reduce the weight of component packaging while providing flexibility to install more flexibly with the shape of the building, the first consideration is to thin the glass and optimize the aluminum alloy frame, but the effect is not great. For example, from 3.2mm glass to 2.0mm glass, the weight per square meter is reduced by about 3kg/square meter. Although thinning the glass reduces the weight of the component, at the same time, it reduces the strength of the component. From a design perspective, the same use conditions may require a reduction in component size. This is because it is necessary to ensure that the component passes the reliability standard test and certification. Therefore, this measure does not fundamentally solve the pain point. At present, if the large-size battery cells produced on a large scale are encapsulated with glass, the excessive weight of the components will be extremely inconvenient when installed on the roof. Moreover, glass components are fragile during transportation and construction, which poses a safety hazard. Therefore, glass-encapsulated components are mainly suitable for large-scale applications such as ground power stations.
So how to effectively reduce the excessive weight of components caused by encapsulation, so that they can better adapt to the application of rooftop photovoltaics, and find alternative glass as the encapsulation material for components has always been the direction of photovoltaic people's efforts. With the emergence of lightweight encapsulation materials with continuously improved performance, non-glass encapsulation has become possible.
The lightweight component route in the early years was to use fluorine-containing film + glass fiber baseboard as support to replace glass-encapsulated components. It can solve some soft waterproof roofs, such as roofs constructed with TPU, by using adhesive installation. However, the supporting base is still too thick and weighs about 8kg/square meter.
In recent years, with the development of advanced composite materials and modified polymer materials, the packaging performance has been basically the same as that of glass, which can allow the packaged lightweight components to provide photovoltaic efficiency output that meets industry standards in a 25-year working life. It allows non-glass packaging to have the same life as glass-encapsulated components, so it has developed rapidly.