TOPCon技术自2015年起逐步取代PERC成为主流太阳能电池技术，其中激光增强接触优化(LECO)工艺是关键。LECO工艺不仅提高了电池效率，还实现了无铝浆料、零栅线(0BB)方法和更低的烧结温度。德国初创公司Cell Engineering开发的LECO技术已被Q Cells收购并授权给其他制造商。目前，Fraunhofer ISE正致力于用铜电镀替代银浆，以降低生产成本。其M10 TOPCon太阳能电池的铜电镀效率与丝网印刷相当，但银用量减少了93%。此外，钝化边缘技术(PET)和TOPCon后发射极(TOPCoRE)技术也在不断进步，TOPCoRE技术更是有望将效率提升至26%。未来，TOPCon电池有望在多结结构中作为底层电池发挥更大作用。

💡TOPCon技术发展迅速，已超越PERC成为太阳能电池的主流技术，其发展历程中，激光增强接触优化（LECO）工艺起到了至关重要的作用。

⚡️LECO工艺的创新之处在于它解耦了接触，实现了无铝浆料的使用，采用了零栅线（0BB）方法，降低了烧结温度，并使用了不同的硼扩散参数，从而显著提高了电池效率。

💰Fraunhofer ISE正在探索用铜电镀替代银浆，以降低生产成本。初步实验结果表明，铜电镀的效率与丝网印刷相当，但银用量减少了93%。未来有望完全摆脱银的使用。

🛡️钝化边缘技术（PET）可以有效减少电池边缘的能量损失，尤其对于具有高周长电池面积比例的叠瓦或半切电池来说，这项技术非常重要。

🚀TOPCon后发射极（TOPCoRE）技术通过用p型晶圆替代n型晶圆，并取消前导电层，有望将电池效率提高到26%，突破了当前TOPCon技术的限制。它还消除了前表面的固有复合。

He shared that the term TOPCon was coined by Fraunhofer ISE in 2013, following which its industrial implementation started around 2015 by Jolywood and LG.  Since then, TOPCon technology has come a long way to overtake PERC as the leading solar cell technology in industrial use. One of the major contributing factors among several others in its journey is the Laser-Enhanced Contact Optimization (LECO) process.  A game-changing innovation, LECO has been instrumental in increasing TOPCon cell efficiency as it decoupled the contact, and also enabled the use of aluminum-free pastes, zero busbar (0BB) approach, much lower firing temperatures, and very different boron diffusion parameters, said Wolf. Developed by a Germany based start-up, Cell Engineering, the company was fully acquired by Q Cells in 2023, and LECO is now being licensed to other TOPCon cell/module manufacturers. At Fraunhofer ISE, the effort now is on copper plating contacts to replace silver paste consumption that accounts for a large part of the production costs. Fraunhofer ISE has started with a pilot fabrication of M10 TOPCon solar cells with electroplating using copper. The initial batch demonstrated similar efficiencies as screen printing at 24% each, but with 93% lower silver usage, he shared. Wolf is confident that plating cells will be able to be processed without silver consumption in the future - by using Sn as the capping layer for copper instead of silver.Passivated Edge Technology (PET), developed at Fraunhofer ISE, helps recover losses by passivating the edges of shingled or half-cut cells. He said it is especially valuable for high perimeter cell area fractions. However, several manufacturers have developed their own methods to achieve these results.Wolf also talked about TOPCon Rear Emitter (TOPCoRE) technology which replaces n-type by p-type wafers, with no front conductive layer and the efficiency can go up to 26%, as against 25.8% in TOPCon. Its major benefit is that it omits inherent recombination of the front surface which is a limitation for the current TOPCon technology. However, the challenge is related to the alignment of the structures which can be met by industrial production conditions.In the future, Wolf sees TOPCon cells as forming a good choice for the bottom cell in a tandem structure in a multi-junction configuration.For more presentation videos and conference summaries for all 4 days of the TaiyangNews High Efficiency Solar Technologies 2024 Conference, click here for days 1 and 2, and here for days 3 and 4.