Major changes necessary for thermal management of LEDs

Global electrochemicals manufacturer Electrolube has addressed growing concerns affecting LED manufacturers regarding the thermal management of LEDs. The changes that will impact on the LED market are being driven by two major factors surrounding the issue of silicone.

Firstly, silicone-based thermal management materials have been found to contribute to problems with long-term reliability and contamination. According to a report from The Lighting Industry Association, a European trade association dedicated to serving the UK lighting industry and its supply chain, some VOCs and chemicals may react with the silicone dome of LEDs to produce discolouration and surface damage, which may affect the total light output. However, some VOCs may not chemically react with the silicone material directly but may diffuse into the silicone and oxidise during the presence of heat or light. The long-term reliability issues of silicone-based products are now causing global LED manufacturers to shift their demand towards non-silicone products.

The second factor contributing to the increasing demand for non-silicone products is the global shortage of silicone, which is forcing suppliers to pass on price increases to customers. Some manufacturers of silicone-based thermal management products are warning of hefty price increases up to 25%. However, the ever escalating growth of the global LED market will further fuel the trend towards non-silicone solutions and is expected to last until 2022. Accommodating the forthcoming market changes, Electrolube’s range of non-silicone thermal management solutions delivers a high-performance alternative to silicone materials and provides LED manufacturers with an immediate drop-in solution.

Thermal management substantially impacts on the lifetime, cost and performance of an LED luminaire. Without suitable thermal management, a luminaire will be thermally inefficient, have a reduced operating life and encompass high maintenance costs. Electrolube’s expansive range of thermal management products includes encapsulation resins, thermal pastes, bonding products, thermal gap pads and phase-change materials that incorporate a variety of different blend materials, such as epoxies, polyurethanes, silicone and non-silicone products.

Electrolube’s non-silicone thermal pastes include HTC (Heat Transfer Compound) and HTCP (Heat Transfer Compound Plus), which avoid silicone migration onto electrical contacts. Potential issues with silicone migration include high contact resistance, arcing, soldering problems and mechanical wear. The company’s ‘X’ range of non-silicone thermal products features the low-viscosity HTCX, for ease of use, and HTCPX, for gap filling applications. These ‘Xtra’ versions of HTC and HTCP provide increased thermal conductivity, lower oil-bleed and lower evaporation weight loss, making them comparable or better than some silicone-based materials. Both products provide a wide operating temperature range from -50 to +180°C and demonstrate good dielectric strength of 42 kV/mm.

With thermal conductivity of 1.35 W/mK, HTCX provides good stability, making it suitable for applications exposed to varying temperature and humidity conditions. The non-silicone HTCPX has high thermal conductivity of 3.4 W/mK, which assists rapid heat dissipation over uneven surfaces. Due to its high viscosity, the material offers stability under vibration, making it suitable for use as a gap-filling material.

Electrolube is represented in over 55 countries with an established network of subsidiaries and distributors. With three manufacturing base options, located in the UK, China and India, the company provides security of scale, delivering a tailored service with good technical support.