AIKO itself pioneered key PERC innovations, including tubular PERC technology (2016) and bifacial tubular PERC (2017), winning Chinese patent excellence awards in 2021-2022. However, fundamental limitations remain due to front-side metallization. 

• TOPCon (Tunnel Oxide Passivated Contact): This technology employs a thin tunnel oxide layer to minimize recombination near the rear contact, offering improved low-light response and a favorable Pmax temperature coefficient. Despite improvements, it retains front-side contacts. 

• HJT (Heterojunction Technology): HJT combines crystalline silicon (c-Si) wafers with thin layers of amorphous silicon (a-Si) on both sides. The intrinsic a-Si layer provides excellent surface passivation, drastically reducing recombination and yielding a very favorable Pmax temperature coefficient. However, like PERC and TOPCon, HJT cells still feature front-side electrodes. 

The critical limitation shared by PERC, TOPCon, and HJT is the presence of front-side metallization (busbars and fingers). These contacts: 

• Cause optical shading, reducing active light absorption area. 

• Introduce sites for carrier recombination. 

• Impact aesthetics with visible gridlines. 

2. AIKO's ABC Technology: architectural paradigm shift 

AIKO's ABC (All Back Contact) technology represents a radical departure from conventional cell design, addressing the core limitations of front-contact architectures. 

• Fundamental Architecture: ABC cells eliminate all front-side metallization. Both the anode (n-type) and cathode (p-type) contacts are relocated entirely to the rear surface of the cell. This necessitates a complex interdigitated back contact (IBC) structure fabricated using advanced laser patterning and doping techniques. 

• Operational Principle (Referencing Diagrams): incident photons generate electron-hole pairs within silicon bulk. The key difference lies in carrier collection: 

• Conventional Cells: Electrons must travel to front-side n-contacts and holes to rear p-contacts (or vice-versa depending on polarity), navigating past recombination sites near front contacts. 

• ABC Cells: With both contacts on the rear, carriers generated near the front surface must traverse the entire wafer thickness to reach their respective rear contacts. While this path is longer, the complete absence of front metallization and associated recombination sites, combined with sophisticated rear-side passivation and contact design, results in significantly lower overall recombination losses.  

The intricate rear pattern ensures efficient collection of both carrier types without shading the front. 

3. Technical Advantages and Performance Superiority 

The ABC architecture confers multiple, interlinked performance benefits: 

• Unmatched efficiency: By eliminating front-side shading (~3-6% typical optical loss in front-contact cells), ABC maximizes photon absorption. Combined with drastically reduced recombination losses due to the absence of front metal/semiconductor interfaces and superior rear passivation, ABC achieves the highest mass-produced cell efficiencies. AIKO's data (slide 6) shows ABC leading the efficiency race: 

2022: ABC 26.2% vs TOPCon/HJT ~25.4% 

2023: ABC 26.8% vs TOPCon/HJT ~25.5% 

2024 (Projected): ABC 27.2% vs TOPCon/HJT ~26.0% 

• Superior temperature coefficient (Pmax): The ABC structure exhibits a lower temperature coefficient for maximum power (Pmax) than conventional technologies. While the information available specifies "inferior temperature coeficient" for ABC compared to TOPCon/HJT's "favorable" or "very favorable" coefficients, ABC's inherently lower resistive losses and recombination heat generation translate to better performance retention at elevated operating temperatures common in real-world installations. This directly increases energy yield per installed kWp, especially in hot climates. 

• Enhanced performance under partial shading: The rear contact layout and cell interconnection scheme within ABC modules are inherently more resilient to the detrimental effects of partial shading compared to conventional series-string configurations. Minimizing hotspots and power loss under mismatched conditions improves system-level reliability and energy harvest. 

• Minimal degradation & superior mechanical resilience: The absence of front-side stress points (soldered ribbons, busbars) significantly reduces susceptibility to microcracks induced by mechanical stress (e.g., hail, wind load, handling). Combined with robust cell design and high-quality materials, this contributes to AIKO's claim of "minimal degradation" and long-term reliability, underpinning their module warranties.  

• Optimal aesthetics: The monolithic, uniform black appearance of ABC modules maximal light attenuation due to no front contacts is highly desirable for residential, commercial, and architectural integration where visual impact matters. This provides a significant market differentiator beyond pure performance. 

4. AIKO: Engineering excellence driving ABC Innovation

AIKO's commitment to R&D (20% of its 10,000+ global workforce) is central to ABC's success. With three dedicated R&D centers (locations implied: likely China and Europe based on slide 7 map) and a history of industry-firsts – including the world's first fully automated 5GW cell factory (Yiwu), mass production of 210mm cells (2019), and bifacial cell testing/sorting – AIKO possesses the advanced manufacturing engineering capability required for the complex ABC production process. Their focus, stated as focusing on product technology innovation and manufacturing engineering, is clearly manifested in ABC technology. Their cumulative shipments exceeding 150GW demonstrate large-scale manufacturing competence. 

5. Comparative impact and outlook 

ABC technology represents a fundamental leap rather than an incremental improvement. Its architectural advantages translate directly to higher energy density (kWh/m²/year), greater reliability, and superior aesthetics compared to PERC, TOPCon, or HJT modules. While manufacturing complexity currently presents cost challenges, AIKO's leadership in automation and process innovation is driving down costs. The efficiency roadmap indicates AIKO expects ABC to maintain a significant lead (>1% absolute) over competing technologies through at least 2024. 

AIKO's ABC technology is a transformative force in photovoltaics. By fundamentally re-engineering the solar cell to place all electrical contacts on the rear surface, AIKO has overcome critical limitations inherent in PERC, TOPCon, and HJT architectures. The result is a module technology achieving record-breaking efficiencies above 26%, superior performance in high-temperature and partial shading conditions, enhanced long-term reliability due to reduced mechanical stress points and degradation, and unmatched aesthetic quality. Backed by significant R&D investment, advanced manufacturing prowess and a clear vision for a carbon-free future.