What is Thermal Grease? Detailed Features of Thermal Grease for Electronic Power Industry

In the manufacturing of energy storage power supplies, charging piles, industrial power supplies and photovoltaic inverters, continuous heat generation of power devices has always been a key concern for engineers and purchasers. Long-term operation of components under high temperature will accelerate aging, shorten the service life of the whole machine, and in severe cases, directly lead to equipment failure.
As a core thermal interface material, thermal grease is one of the most widely adopted solutions to dissipate heat from power devices. Many novice purchasers in small and micro enterprises often select inappropriate materials due to lack of understanding of product characteristics, resulting in mass defective products.
1. What is Thermal Grease
Thermal grease, also known as heat sink compound, is a paste thermal medium compounded by silicone base oil and thermal conductive powder. Different from thermal silicone pads and thermal structural adhesives, thermal grease will not cure and remains pasty permanently. Its main function is to fill tiny uneven gaps between heat sinks and chips, MOSFETs and IGBTs to expel trapped air. Air has poor thermal conductivity. After filling the gaps, the interfacial thermal resistance can be effectively reduced, and heat generated by components can be conducted out rapidly.
Kimidun TG-P300 thermal grease is a standard model developed for the electronic power supply industry. Key parameters: thermal conductivity 3.0W/m·K, operating temperature range -40℃～200℃, low oil separation, low volatility, high volume resistivity and excellent insulation performance, meeting heat dissipation requirements for most power supply equipment.
2. Main Application Scenarios in Electronic Power Industry
Heat dissipation for energy storage BMS circuit boards and power modules of household storage inverters;
Interfacial filling for IGBTs, rectifier tubes and drive modules of new energy charging piles;
Heat dissipation for MOSFETs and transformers of industrial switching power supplies and server power supplies;
Thermal filling for power devices of photovoltaic micro-inverters and vehicle-mounted power supplies.
It applies to scenarios where heat sinks and components are compressed by screws or clamps. It only provides thermal conduction without adhesion, facilitating later equipment maintenance, disassembly and rework of components.
3. Common Selection Misunderstandings for Purchasers of Small & Micro Enterprises
Misunderstanding 1: The higher thermal conductivity, the better
Many purchasers blindly pursue products with ultra-high thermal conductivity. Thermal grease with higher thermal conductivity comes with much higher cost. If the heating power of equipment is low, models within 3.0W/m·K are fully sufficient. Excessively high parameters only raise production costs and cause budget waste.
Misunderstanding 2: Confuse thermal grease and thermal silicone adhesive
Thermal silicone adhesive (generally room-temperature curable thermal silicone rubber) cures into elastic colloid with adhesion capacity. Thermal grease never cures and only conducts heat. If purchasers mistakenly use thermal silicone adhesive instead of thermal grease, the heat sink will be stuck and cannot be disassembled during maintenance, greatly increasing after-sales costs.
Misunderstanding 3: Ignore oil separation and volatility indicators
Low-cost inferior thermal grease tends to bleed oil under long-term high temperature. The precipitated silicone oil contaminates PCB circuit boards, which may cause electric leakage and component corrosion. Many small power supply manufacturers have encountered such mass quality failures.
4. Practical Selection Suggestions
Ordinary industrial power supplies and low-power adapters: Prioritize thermal grease of 2.0～3.0W/m·K for optimal cost performance.
High-power modules for charging piles and energy storage: Recommend Kimidun TG-P300 (3.0W/m·K), balancing temperature resistance and long-term stability.
Equipment working outdoors under persistent high temperature: Focus on verifying oil separation rate and high-temperature aging data.
Products exported to Europe and the United States: Confirm the materials have RoHS and REACH compliance test reports.
5. Practical Application Case
A small industrial power supply manufacturer in Jiangxi previously purchased low-cost, uncertified thermal compound. After 6 months of operation, PCB contamination caused by oil bleeding occurred continuously. After sample testing, the manufacturer switched to Kimidun TG-P300 thermal grease. No obvious oil bleeding was observed after 500 consecutive hours of 85℃ & 85%RH damp heat test, and the overall product failure rate decreased significantly. Meanwhile, the material meets export standards, helping the enterprise obtain overseas orders for small power supplies.
Summary
Thermal grease cannot be simply regarded as general consumables. Only matched parameters and suitable working conditions can guarantee stable heat dissipation while controlling costs. For power supply manufacturers, selecting proper thermal interface materials can effectively reduce equipment return rates. If you are seeking electronic thermal materials with stable supply, contact Kimidun for sample testing. We provide professional technical support for model selection according to your product working conditions.