Applications of silver in industry

Silver (Ag) is classified as an “irreplaceable strategic metal” in the industrial sector due to its extraordinary physical and chemical properties—specifically possessing the highest electrical conductivity, thermal conductivity, and reflectivity of all metals.

The following are the primary industrial applications of silver:

1. Photovoltaics (Solar Cells)

This is currently the largest growth sector for industrial silver demand. Silver powder is processed into conductive silver paste and applied to silicon wafers via screen printing to form the busbars and fingers that collect photo-generated current.

• Property Utilized: Extreme electrical conductivity.

• Trend: As the global transition to renewable energy accelerates, solar silver demand accounts for approximately 20% of total industrial silver use in 2026. Despite “thrifting” efforts (like copper plating), silver remains vital for high-efficiency cells such as TOPCon and HJT.

2. Electrical and Electronics Engineering

Silver is found in almost every modern electronic device.

• Contacts and Switches: In circuit breakers, relays, and switches, silver contacts can withstand arcing without fracturing or welding together, ensuring long-term conductive stability.

• Multilayer Ceramic Capacitors (MLCC): Silver is used as internal electrodes for high-performance capacitors.

• Flexible Electronics: Silver nanowires and pastes are used in wearable devices and flexible circuits for foldable screens.

3. Electric Vehicles (EVs) and Automotive Electronics

As vehicles shift from mechanical to electronic propulsion, silver consumption has increased significantly.

• Applications: Battery Management Systems (BMS), power drive units, radar and sensors, heated glass, and charging piles.

• Comparison: A traditional internal combustion engine (ICE) vehicle uses an average of 15–28g of silver, whereas a battery electric vehicle (BEV) can use between 25–50g.

4. Brazing and Alloys

Silver alloys possess excellent wettability and strength, making them ideal for joining metals.

• Silver Brazing Fillers: Fillers containing 20%–70% silver are used in air conditioning, refrigeration, aerospace engines, and power distribution systems. They produce exceptionally strong, vibration-resistant joints that are lead-free and non-toxic.

5. Industrial Catalysts (Chemical Synthesis)

In the chemical industry, silver acts as a highly efficient oxidation catalyst.

• Ethylene Oxide Production: This is silver’s most critical chemical application. Ethylene oxide is a base raw material for polyester (textiles), antifreeze, and detergents.

• Formaldehyde Production: Silver catalysts also convert methanol into formaldehyde, used in resins, adhesives, and plastics.

6. Medical and Healthcare (Antimicrobial Applications)

Silver ions have potent bactericidal properties and are less likely to induce bacterial resistance.

• Medical Devices: Silver coatings are used on catheters, surgical instruments, and burn dressings (e.g., silver nitrate dressings) to prevent infection.

• Water Treatment: Silver ions are used in hospital water systems, swimming pools, and even water purification systems on manned spacecraft.

7. Mirrors and Optical Coatings

Silver reflects over 98% of light in the visible spectrum.

• Applications: High-end architectural glass (Low-E glass) coatings to reflect infrared light for energy saving, telescope mirrors, Concentrated Solar Power (CSP), and high-quality decorative mirrors.

Summary: Structural Shifts in Silver Demand