What is a Liquid Cold Plate?
A Liquid Cold Plate (also referred to as a liquid cooling plate) is a high-efficiency heat dissipation device, typically made of aluminum or copper. It features precisely machined internal flow channels where cooling fluid circulates to absorb and carry away heat generated by electronic components, thereby maintaining the stable operating temperature of equipment.
Compared with air cooling, liquid cooling offers higher heat dissipation efficiency and is particularly suitable for high-power, high heat density application scenarios such as electronic control systems of new energy vehicles, 5G base stations, energy storage equipment and servers.
Types of Liquid Cold Plates
Based on different manufacturing processes, liquid cold plates can be categorized into tube-embedded liquid cold plates, vacuum brazed liquid cold plates, friction stir welded liquid cold plates, etc.
1. Tube-Embedded Liquid Cold Plates
Grooves matching the shape of flow channels are machined on an aluminum substrate by CNC processing, after which copper or stainless steel tubes are inserted into the grooves. Meanwhile, high thermal conductivity epoxy resin or solder paste is applied inside the grooves to enhance and assist heat transfer.
Features:
- Simple manufacturing process and relatively low cost
- Suitable for medium heat dissipation requirements
- Limited flexibility in flow channel design due to the constraints of copper tube bending and layout
- constraints of copper tube bending and layout
2. Vacuum Brazed Liquid Cold Plates
Components including aluminum substrates, water chamber structural parts and cover plates are assembled and then placed in a vacuum furnace for brazing at a temperature where the solder melts but the base metal remains solid.
Features:
- High strength and compact structure
- Flexibly machinable flow channels as per design requirements
- Applicable to high-power and high-reliability scenarios
- Relatively high manufacturing cost and equipment requirements
3. Friction Stir Welded (FSW) Liquid Cold Plates
Friction Stir Welded liquid cold plates (abbreviated as FSW liquid cold plates) utilize a high-speed rotating stirring pin to generate heat through friction with metal, bringing the metal at the joint into a plastic state and forming a firm bond through stirring.
Features:
- No filler solder required, a solid-state welding process that is environmentally friendly and reliable
- High joint strength and excellent sealing performance
- Flexibly machinable flow channels, suitable for the design of complex liquid cold plates
- High requirements for manufacturing precision
Advantages of Liquid Cold Plates
As a high-efficiency heat dissipation device, liquid cold plates are widely used in the thermal management of IGBTs, GTOs and other high-power components. They can precisely control the temperature of power modules to keep it within the range permitted by standard specifications, thus:
- Ensuring the safe, stable and reliable operation of power modules
- Extending the service life of equipment
- Improving the working efficiency of the overall system
What Advantages Do Liquid Cold Plates Offer?
With the continuous increase in power density, traditional air cooling can no longer meet modern heat dissipation demands. Relying on superior heat transfer performance, liquid cold plates have gradually become the mainstream solution.
Advantage Comparison
- Higher heat dissipation capacity: The heat capacity of water is about 4 times that of air. Under the same temperature rise and flow rate conditions, water absorbs 4 times the heat of air.
- Lower noise: Liquid cooling systems do not rely on high-speed fans, resulting in almost negligible operating noise.
- Ideal for high heat flux scenarios: Capable of meeting the urgent high-efficiency heat dissipation needs of industries such as new energy vehicles, data centers and industrial power supplies.
What Liquid is Used in Liquid Cold Plates?
Commonly used liquid: Pure water
Optional liquids: Ethylene glycol solution, refrigerant, insulating cooling fluid, etc.
We can select the appropriate cooling fluid according to customer requirements to match different application environments.
Application Scenarios of Liquid Cold Plates
Liquid cold plates have a wide range of applications, including: battery systems of renewable energy vehicles, telecommunication systems, medical equipment, railway and public transportation, IGBT and power semiconductor systems, laser equipment, TEC, data centers, industrial power supply applications, defense systems, avionics, fuel cells, power electronics, battery cooling, as well as many other high-power and high heat flux applications and devices.
Why is Copper More Commonly Used for the Inlet and Outlet Ports of Liquid Cold Plates?
First and foremost, the inlet and outlet ports of liquid cold plates are attached to chips to absorb and transfer heat, so the material must have high thermal conductivity. Electronic chips require rapid heat dissipation, making metal materials the preferred choice. The thermal conductivity of copper is 377 W/(m·K), aluminum 237 W/(m·K), and silver 412 W/(m·K). Silver is not used for inlet and outlet connectors due to its excessively high cost. In addition, copper is more easy to machine and form.
In comparison, copper is the optimal choice for the inlet and outlet connectors of liquid cold plates.
-
Written by
CoolingThermal Engineering TeamCoolingThermal is an automation equipment manufacturer based in Kunshan, China, specializing in heat pipe and vapor chamber production equipment since 2017. Our engineering team designs, builds, and commissions complete production lines covering forming, degassing, welding, testing, and assembly processes. The technical content on this blog is written by the same team that develops the equipment — based on real production experience, not secondary research.
