Zero Bushbar 0BB Technology Emerges in SNEC EXPO Shanghai 2025

0BB Shows A Critical Window for Solar Innovation

The solar industry is at a crossroads. Major breakthroughs in core photovoltaic (PV) technologies have stalLed. Competing approaches likeBC (Back Contact), HJT (Heterojunction), and topcon (Tunnel Oxide Passivated Contact) are locked in a stalemate, while emerging technologies like tandem cells and perovskites are still ramping up toward commercial readiness.

In the absence of a game-changing “super innovation,” micro-innovations are now the main force pushing the industry forward—especially those that reduce costs and improve efficiency.

Key micro-innovation focus areas:

• Reducing or eliminating silver (Ag) usage
• Upgrading solar cell technologies
• Improving module design and functionality
• Innovating at the system and application level

0BB Technology Shines at SNEC 2025 in Shanghai

At the SNEC 2025 Solar Expo in Shanghai, 0BB (Zero Busbar) technology emerged as one of the most talked-about innovations. Major players like LONGi, Tongwei, Aiko Solar, Jinko, JA Solar, and Huasun unveiled their latest 0BB-based modules, marking a pivotal moment in the commercialization of this advanced interconnection technology.

With its ability to reduce silver usage and enhance performance across multiple solar cell platforms, 0BB is quickly becoming the industry's go-to strategy for achieving cost-effective, high-efficiency modules. The expo highlighted not only its technical maturity but also its growing adoption across HJT, BC, and TOPCon product lines.

0BB – The Front-Runner in Cutting Silver Paste Costs

Silver paste is the second most expensive material in PV cell production. As silicon prices fall, silver’s cost-share rises—currently around 27% of cell cost (excluding depreciation).

Two main strategies have emerged to cut silver paste costs:

• Gridline optimization: 0BB, MBB, SmartWire, screen printing, etc.
• Material substitution: silver-coated copper, copper plating, copper paste, aluminum paste

Of these, 0BB is the most mature and widely used today. It works by removing the main busbars from the cell. Instead, ribbons or wires directly connect the cell’s fine fingers to the module.

This simple change can cut silver use by 20–40%, especially for silver-heavy technologies like HJT and BC. It’s a minimalistic yet highly efficient evolution in cell design.

Zero Bushbar – A Strategic Lever in the Cell Technology Race

As cell technologies compete, 0BB proves to be a versatile enabler that supports each in different ways.

Challenges facing each technology:

• HJT: High silver usage, needs cost reduction
• BC: Complex back-grid, high silver use, lower bifacial rate
• TOPCon: Needs higher efficiency and module power

0BB helps by reducing silver cost, minimizing light shading, lowering resistance, improving packaging efficiency, increasing power output, and boosting aesthetics and yield rates.

Real-world adoption examples:

• HJT: Huasun, Risen use 0BB to reduce silver costs
• BC: LONGi, Aiko Solar use 0BB for bifacial efficiency and simplified packaging
• TOPCon: Jinko, JA Solar, Tongwei, and others use 0BB to stay competitive

At the 2024 SNEC Expo, 0BB featured prominently across technologies, reflecting its growing importance.

0BB Technology Approaches – Which is Best?

0BB was first introduced as SmartWire by Day4 Energy in 2003. The tech was later acquired by Meyer Burger, and patents expired in 2023—opening the door for broader use.

1. Dispensing (Glue Attachment): Glues ribbons to cells before lamination.
   ✅ Simple equipment
   ❌ Weak adhesion, potential light loss


2. Welding + Glue: Welds ribbons first, then glues for reinforcement.
   ✅ Stronger adhesion
   ❌ High-temp process, higher complexity


3. Direct Film Coating (IFC): Uses skin-film to press ribbons onto cells precisely at low temps.
   ✅ Strong bonding, fine wires, supports tight spacing
   ❌ Slightly higher film material cost

IFC has emerged as the most balanced and scalable solution. It's already widely adopted in HJT, BC, and TOPCon modules. It enables:

• Low-temp processing with no warping
• Higher yields and better support for thin cells
• Direct use of round ribbons for improved bifaciality
• Elimination of solder paste steps

Thanks to domestic equipment makers, 0BB technology is evolving rapidly in stability and performance across cell types.

Conclusion: Micro Innovation, Major Impact

In a crowded and highly competitive PV market, the smallest innovations often drive the biggest differentiation.

0BB stands out as a key solution that touches both cell and module production. It lowers costs, boosts performance, and provides visual and structural benefits.

With continued adoption by leading firms and maturing manufacturing processes, 0BB’s market share is set to grow— making it a standout success in the world of solar micro-innovations.

Bottom line: 0BB is no longer just a clever trick—it's becoming the standard.