What does BC battery mean in photovoltaic modules?
The BC battery stands for Back Contact Battery, and its base type is the IBC battery (Interdigitated Back Contact Battery).
The most significant difference compared to other crystalline silicon battery technologies is that the emitter layer, surface field, and metal electrodes are all located on the back of the battery, distributed in a cross-finger pattern. This design allows the front surface of the battery to be free of any gridlines, maximizing the utilization of incident light, reducing optical losses, and providing a larger effective power generation area. It results in higher conversion efficiency and a more aesthetically pleasing appearance.
The IBC battery is a relatively pure single-sided battery, primarily enhancing conversion efficiency through structural changes. The IBC battery does not have metal contacts on the front surface, which allows for a higher photon impact conversion area.
Strictly speaking, the BC battery refers to a battery manufacturing technology that optimizes the structure, rather than a separate type of battery cell. Both P-type and N-type batteries can incorporate BC battery technology to create new types of cells. A P-type battery with BC technology is called PBC. A TOPCon battery with BC technology is called TBC. A HJT battery with BC technology is called HBC. Currently, major technological routes include IBC, HBC, PBC, ABC, HPBC, and others.
With the rapid development of the photovoltaic industry, technological iterations and upgrades in the field have accelerated. As of now, photovoltaic cells have evolved through the first generation of crystalline silicon cells, the second generation of thin-film cells, and the third generation of new-type cells. Among these, silicon-based cells are divided into P-type and N-type cells. N-type cells can further be subdivided into TOPCon, HJT, IBC, and HBC (HJT + IBC) types.