R & D - Alishan Green Energy

Solar module's life of 25 years depends mostly on the EVA encapsulant. It gives physical protection to the solar modules, best electrical insulation, moisture protection, high transparency etc, such critical properties are best maintained in our EVA with our team of expertise and with proven raw materials.

Our EVA's prime properties are :

Custom made UV cut off wavelength,

Excellent moisture resistant and weather resistant,

Excellent adhesion with glass and backsheet,

Excellent PID resistance/electrical insulation,

No discolouration or yellowing,

Excellent thermal stability,

Excellent transparency.

UV Visible spectrophotometer used for stringent quality control testing of UV cut off, Yellowness Index and Transmittance % of EVA film. UV cutoff is the main parameter to identify whether it should be used as Front EVA or Rear EVA. Transmittance and Yellowness index are the main parameters for reliabiltiy testing of solar EVA. The Δ YI yellowness index before and after a reliability test i.e., Damp Heat, UV exposure etc are strictly maintained at ≤ 3.

Transmittance, UV cutoff and yellow index are tested as per ASTM E 424 test method

Universal Testing Machine can be used to test the :

Tensile strength of EVA,

Elongation of EVA,

Adhesion strength of EVA with glass,

Adhesion strength of EVA with backsheet.

A polymer's reliability is measured in terms of retention % the above mentioned properties, an EVA's properties interms of reliability also evaluated with before and after datas of (of reliability tests) the above properties.

Applicable ASTM test methods are ASTM D 638 and ASTM D 903 for mechanical properties and adhesion testing respectively.

Gel content of EVA is the measure of degree of crosslinking in EVA. Lower the Gel content can indicate the lower degree of crosslinking, which is an serious issue in the reliability and mechanical integrity of solar module.

This gel content of EVA encapsulant can be measured by two methods, one is soxhlate and other is oven method. This is an important parameter as a part of stringent quality control tests. Though this is a time consuming test, but very important, reliable and a mandatry test in solar module or EVA manufacturing process.

The test method followed is ASTM D 2765

Lab scale laminator, to prepare samples for testing, usually A4 size modules were made for all testing, with solar glass, 2 layers of EVA and a backsheet. This laminator is also used to set the laminator recipe which will be helpful to set laminator recipe at customer end.

This laminator is mainly used for preparing samples for regular quality testing and to prepare modules for any alternate materials to test in reliability chambers.