IBC (Interdigitated Back Contact) transfers all the electrode grid lines on the front side of the solar cell to the back side of the solar cell. The PN junction and metal contacts are all on the back side of the solar cell, arranged in an interdigitated manner to reduce the blocking of sunlight by the front grid lines. The light trapping structure composed of pyramid suede structure and anti-reflection layer can maximize the use of incident light. IBC solar cell mainly improves conversion efficiency through structural changes and is a relatively pure single-sided solar cell. This not only brings more effective power generation area to users, but also helps improve power generation efficiency and makes the appearance more beautiful.


 
Advantages and Disadvantages of IBC Solar Cells
 
The unique structural design of IBC solar cells gives it the following advantages:
1) There is no grid line shielding on the front of the solar cell, which can eliminate the light-shielding current loss of the metal electrode and maximize the utilization of incident photons. Compared with conventional solar cells, the short-circuit current can be increased by about 7%;
2) Both the positive and negative electrodes are on the back of the solar cell. There is no need to consider the grid line occlusion problem. The grid line ratio can be appropriately widened to reduce the series resistance and increase the fill factor FF;
3) Since the front side does not need to consider factors such as gate line shading and metal contact, the surface passivation and surface light trapping structure can be optimally designed to obtain a lower front surface recombination rate and surface reflection, thereby increasing the open circuit voltage Voc and Short circuit current Isc;
4) Beautiful appearance, especially suitable for building-integrated photovoltaic BIPV, with good commercial prospects;
 
At the same time, the production and manufacturing of IBC solar cells also faces many challenges:
1) It has higher requirements on the matrix material and requires a higher minority carrier lifetime. Because IBC solar cells are back junction cells, in order to prevent photogenerated carriers from being recombined as little as possible or not at all before reaching the back p-n junction, a higher minority carrier diffusion length is required.
2) IBC solar cells have higher requirements for passivation of the front surface. If the front surface recombination is high, the photogenerated carriers will be recombinated before reaching the back p-n junction area, which will significantly reduce the solar cell conversion efficiency.
3) The process is complex. The cross-shaped p-region and n-region on the back require multiple masking techniques during the production process. In order to prevent leakage, the gap area between the p-region and n-region also needs to be very precise, which undoubtedly increases the difficulty and cost of the process.

IBC Solar Panel