What is a BC battery?

The base type of BC battery is IBC battery (Interdigitated Back Contact) which is a pure single-sided battery.

Unlike TOPCON and HJT, which adopt a new passivation contact structure to improve the passivation effect and thus improve the conversion efficiency, the PN junction and metal contact of IBC are located on the back of the solar cell, and there is no metal grid wire shielding on the front, eliminating the front metal electrode structure. Therefore, BC batteries can maximize the use of incident light and bring more effective power generation area, so as to improve the energy conversion efficiency of the battery and have a beautiful appearance.

  As a platform technology, IBC can be combined with P-type, HJT, TOPCON and other technologies to form HPBC, HBC (compatible with partial HJT process), TBC and other technical routes (compatible with partial TOPCON process). For example, the superposition with TOPCON technology is called TBC battery, and the superposition with HJT technology is called HBC battery. These batteries are collectively referred to as BC batteries.

  At present, the BC structure is divided into three routes: a) the classic IBC battery process represented by SunPower; b) the HBC process represented by KANEKA (Zhonghua Co., Ltd.); c) the POLO-IBC process represented by ISFH (Mulin Solar Energy Research Institute) .

SunPower, an American solar company, is the pioneer of IBC batteries and has a rich patent reserve. In 2019, SunPower in the United States was divided into two parts. SunPower still focuses on residential and commercial solar and battery energy storage systems in the United States. It separated the original solar cell manufacturing business and established another company, Maxeon Solar (MAXN.O), focusing on IB. C battery structure.