The term “semi-flexible” solar panel is an oxymoron. It suggests the solar panel to be partly flexible. The oxymoron derives from what is inside the solar panel, a rigid crystalline Silicon solar cell.
So then what happens when you bend a semi-flexible solar panel built with solar cells which theoretically are not flexible?
Mechanical stress such as bending or walking will cause the crystalline cell to develop hair line or micro cracks. With continued handling and bending, micro cracks accumulate in the cell and these cracks will not “go away” or “heal” in some miraculous way. The cells increasingly loose output over time. Manufacturers indicate to bend max. 30 degrees. The example above is clearly beyond 30 degrees causing excessive stress in the cells.
Here is why: 99% of all semi-flexible solar panels are built with standard crystalline Silicon cells with fingers and bus bars:
The fingers “capture” the electrons and channelling them to the busbars from where they eventually will be leaving the solar panel through the junction box. Micro cracks in the cell break the fingers and interrupt the flow of electrons, preventing them to reach the bus bars, thus the solar panel losing output.
The following image (electroluminescence) shows the presence of micro cracks in a fresh out of the box 100W Chinese product distributed in South Africa:
This fresh out of the box solar panel has already had its fair share of “abuse” judging by the number of cracks and dead cell areas. Every cell in this example has been compromised. Officially labeled as 100W, highly doubtful it will have a meaningful performance.
The Flexopower Tacoma 145 is built with a 2 dimensional grid cell without bus bars, making the entire solar panel resilient to micro cracks. The 2D cell grid captures electrons and circumventing micro cracks. Electrons flow without loss to the junction box. The solar panel does not loose output.
The following image (electroluminescence) shows the cell with micro cracks after 2 mechanical impacts. As seen in the corresponding measurements, no loss in output is observed due to the innovative 2D grid.
In summary, semi-flexible solar panels are built with crystalline solar cells, which develop micro cracks during bending and mechanical stress. The Flexopower Tacoma-145 is the only semi-flexible solar panel in the market with a 2D cell grid managing micro-cracks.