The Key Role of Sealing Aluminum Pins in Batteries

New energy power and energy storage batteries contain a small but essential component: the sealing aluminum pins. Hidden in the electrolyte injection hole of the battery cover, this sealing pins is the main barrier for battery sealing, safety, and performance stability. It directly affects the battery’s lifespan and operational safety.

What are Sealing Aluminum Pins?

Sealing aluminum pins are precision-stamped components for battery covers. They work with the electrolyte injection holes of power and energy storage batteries. Each pins has a head and a body and is highly precise. Used with sealing adhesive pins, they are fixed by laser welding. They are a core part of battery encapsulation.

Three Key Functions of Sealing Aluminum Pins

♦ Tight Sealing to Prevent Electrolyte Leakage

After electrolyte filling, laser-welded sealing aluminum pins close the holes, creating a sealed space. This stops electrolyte leaks, oxidation, and air contact. It also blocks moisture and impurities, keeping the cell’s chemical environment stable. This is the aluminum pin’s most important function.

♦ Collaborative Explosion-Proofing for Enhanced Battery Safety

The aluminum pins work alongside the battery’s safety vents—a safety device that releases excess gas to prevent bursting—and terminals (connection points that transfer electrical current). They do not interfere with the normal operation of these safety features. When battery pressure increases abnormally, the battery safety vents releases the pressure, and the sealing pins maintain their integrity, preventing leaks or failures and maintaining safety in the battery packaging.

♦Stable Structure, Extended Battery Service Life

The aluminum pins are highly corrosion-resistant and mechanically strong. They resist erosion by internal chemicals. They also withstand impacts from driving vibrations and minor collisions. This prevents loosening and cracking of the sealing points. The structure remains stable under repeated charging, discharging, and temperature changes, effectively extending battery lifespan.

Difference Between Good and Bad Sealing of Aluminum Pins

A good sealing aluminum parts has the following features. These directly affect battery reliability and life:

• High sealing: Welds have no pinholes, cracks, or bursts. The seal stays stable, even with residual electrolyte.
• Reliable material: Made from high-purity aluminum alloy, flexible, weldable, corrosion-resistant, and anti-aging.
• High accuracy: Tolerances for diameter, height, and roundness are within ±0.01mm. This ensures a precise fit and prevents damage from incorrect pressure.
• Clean surface: Smooth, free of oil or oxide. This reduces welding spatter, stabilizes the weld, and improves yield in battery packaging.