TOPCON

Photovoltaic cells can be divided into N-type cells and P-type cells. P-type PERC cells (emitter and back passivation cells) are most used in the current market, and their cell efficiency is generally above 23%. Although the cost of PERC cells has been decreasing in recent years, in terms of efficiency, it has reached its ceiling. Then what other battery slices can take over the baton of PERC batteries?
Looking at the footprints left by photovoltaic players on this track, technological iterations have never stopped. Both TOPCON (tunneling oxide passivated contacts) in N-type cells and HJT cells (heterojunction cells) are accelerating their sprint.

Let’s talk about TOPCON first. While improving the efficiency (more than 1% higher than PERC cells on average), the biggest advantage of this type of battery is that it can be upgraded based on the existing PERC production line without completely abandoning the original production line. According to the author's statistics, LONGi (601012), JinkoSolar, Trina Solar (688599), and Jolywood (300393) are all actively deploying this technology line, and it is recommended that players continue to pay attention to the rhythm of mass production. Last year, JinkoSolar announced that the efficiency of N-type TOPCON cells reached 25.4%, and the N-type large-scale world efficiency record was set four times a year.

After all, in the market alternation brought about by technological iteration, it is the most critical for players to get the cake in their hands first.

Jinko has become more and more brave on the road of TOPCON, and Nalongji is not to be outdone in HJT, and the feat of breaking two world records within a week is still vivid in his mind.

The cost of HJT battery is still slightly higher than that of TOPCON, but the battery parameters (such as attenuation rate, temperature coefficient, bifacial ratio) are better. According to data released by CITIC Construction Investment Research, HJT bifacial cells have a 5-11.8% higher power generation per watt compared to PERC's full life cycle. But the problem is that HJT batteries can't be repaired like TOPCON. Its production process is longer and the production process is more complicated, and it needs the support of the whole industry chain of upstream and downstream and suppliers.
To make a brief summary, if we take a longer-term perspective, the author is more optimistic about the subversion of existing technologies by HJT, and is expected to overtake in corners. But in the short term, TOPCON is expected to run faster.
Author: Bocai（菠菜）
Link: //zhuanlan.zhihu.com/p/455312558
Source: Zhihu