How to Extend the Service Life of LED Lamp Beads?

LED (Light Emitting Diode) technology is widely used in lighting, displays, automotive lighting, plant growth lighting, and more due to its high brightness, low energy consumption, and long lifespan. However, over time, LED brightness gradually decreases, a phenomenon known as luminous decay. This not only affects the lifespan of LED products but also leads to issues such as uneven brightness and color temperature drift.

So, what causes LED luminous decay? What factors affect LED lifespan? And how can we extend the life of LEDs? This article will explore these topics in detail.

1. Major Causes of LED Luminous Decay

Luminous decay in LEDs refers to the gradual reduction in luminous efficiency, usually manifested as a decrease in brightness or a shift in color. The main factors contributing to LED luminous decay include:

(1) Chip Aging

The core of LED lighting is the semiconductor chip, which generates photons when current flows through it. However, the chip is also affected by current impact and high temperatures. Over time, the lattice structure of the chip may degrade, reducing photon recombination efficiency and causing luminous decay.

(2) Insufficient Heat Dissipation

Only 30-40% of the electrical energy input into an LED is converted into light; the remaining 60-70% is converted into heat. If heat dissipation is inadequate, excessive heat buildup accelerates material degradation, leading to faster luminous decay.

Factors affecting LED heat dissipation include:
✅ Heat Dissipation Materials: High thermal conductivity materials such as aluminum substrates and copper heat sinks improve heat dissipation.
✅ Packaging Technology: High-quality thermal silicone and low thermal resistance packaging structures help reduce heat accumulation.
✅ Operating Environment Temperature: LEDs used in high-temperature environments tend to experience faster luminous decay.

(3) Overloaded Current

LEDs require stable current drive, but excessive current can cause:
⚠ Increased junction temperature → Accelerated luminous decay
⚠ PN junction damage → Reduced luminous efficiency
⚠ Blue chip aging → Color temperature drift

Therefore, ensuring a well-designed current regulation system is crucial to prevent current surges that could accelerate luminous decay.

2. How to Reduce Luminous Decay and Extend LED Lifespan?

To slow down luminous decay and extend LED lifespan, improvements can be made in chip quality, driving circuits, and heat dissipation design.

(1) Choose High-Quality LED Chips

High-quality LED chips are manufactured using advanced epitaxial technology and stable lattice structures, allowing them to withstand higher temperatures and currents. This helps minimize luminous decay.

✅ Renowned brands such as Cree, Osram, and Nichia provide highly stable LED chips.
✅ Low thermal resistance packaging technology reduces heat buildup and improves light efficiency stability.

(2) Optimize Driving Circuit to Ensure Stable Current

LEDs require a constant current drive to prevent excessive current fluctuations that cause luminous decay. Methods to optimize the driving circuit include:
✅ Using constant current power supplies to prevent current overload.
✅ Incorporating over-temperature protection and current limiting circuits to prevent LED chip overheating.
✅ Adopting PWM (Pulse Width Modulation) dimming to minimize current impact and extend LED lifespan.

(3) Improve Heat Dissipation to Lower Operating Temperature

Since high temperature is a primary cause of LED luminous decay, optimizing the heat dissipation system is essential for extending LED lifespan. Effective heat dissipation measures include:

✅ Using high thermal conductivity materials such as copper substrates and graphite heat sinks to enhance heat transfer.
✅ Optimizing luminaire structure design by adding heat dissipation fins to improve convection cooling.
✅ Adopting active cooling solutions such as fans and liquid cooling, especially for high-power LED applications.

3. LED Lifespan Calculation and Testing Methods

The lifespan of an LED is typically measured by its lumen maintenance rate. The most commonly used international testing standards include LM-80 certification and L70 lifespan standard.

(1) LM-80 Certification

LM-80 (Lumen Maintenance Test) is a standard set by Energy Star to evaluate long-term LED luminous maintenance performance.

Testing Method:

• LEDs are tested under 55°C, 85°C, or even 105°C environments for 1,000 to 6,000 hours.
• The luminous flux is recorded at different time intervals to plot a luminous decay curve.
• A mathematical model is used to predict the long-term lifespan of the LED.

(2) L70 Lifespan Standard

LED lifetime is typically defined by the time it takes for luminous flux to drop to 70% of its original value (L70). For example:

• If an LED operates for 50,000 hours before its brightness drops to 70%, its L70 lifespan is 50,000 hours.
• Some high-quality LED chips have L70 lifespans of over 100,000 hours, making them ideal for road lighting, industrial lighting, and other long-term applications.

Additionally, long-term LED reliability tests include:
✅ High Temperature & Humidity Test (85°C/85%RH) → Evaluates LED resistance to harsh environments.
✅ Thermal Shock Test → Checks if packaging materials crack or degrade due to temperature fluctuations.
✅ Vibration & Impact Test → Ensures that LEDs do not experience excessive luminous decay under mechanical stress.

4. Conclusion: How to Ensure Long-Term Stable LED Performance?

Luminous decay is a key factor affecting LED lifespan, mainly influenced by chip aging, insufficient heat dissipation, and excessive current load. To minimize luminous decay and extend LED lifespan, consider the following strategies:

✅ Choose high-quality LED chips for long-term stable lighting performance.
✅ Optimize the driving circuit by implementing constant current regulation.
✅ Enhance heat dissipation using high thermal conductivity materials and structural design.
✅ Comply with LM-80 and L70 lifespan testing standards to ensure LED reliability.

In practical applications, selecting high-quality LED products and adopting scientific heat dissipation and driving circuit designs can effectively reduce luminous decay, extend LED lifespan, and enhance lighting efficiency. If you are looking for high-performance LED products, feel free to contact us! We provide top-quality LED lighting solutions tailored to your needs.