With the rapid development of new energy vehicles, electric tools, and energy storage systems, the thermal management system of power batteries has become a key link in ensuring performance, safety, and lifespan. Among them, the water-cooled plate, as the core heat exchange component, widely adopts a structural design of interference fit between copper pipes and aluminum bottom plates to achieve efficient heat dissipation. However, traditional brazing processes face a series of challenges in actual mass production, which has driven the demand for high thermal conductivity structural adhesive solutions from enterprises.
This article will focus on the application scenarios of bonding and sealing copper tubes in battery pack water-cooled plates, analyze the challenges faced, and recommend a high-performance and process friendly structural adhesive – EP 1710 high thermal conductivity epoxy sealant – to assist in the upgrading and iteration of thermal management systems.
1、 Application background: Structural characteristics of copper tube aluminum bottom water-cooled plate
The water-cooled plate is usually composed of a high thermal conductivity aluminum alloy bottom plate and a high thermal conductivity copper tube. The copper tube is responsible for conducting the coolant, while the aluminum bottom plate is in close contact with the battery module to complete heat exchange.
In order to improve heat dissipation efficiency and structural stability, a combination of copper tube and aluminum groove interference fit+brazing reinforcement is often used in design. Although this design exhibits excellent thermal conductivity efficiency, it faces a series of technical difficulties in actual manufacturing.
2、 Application Challenge Analysis
- High difficulty of brazing process
Copper and aluminum belong to different metal systems, and traditional brazing has problems such as poor wetting, poor welding consistency, and easy deformation or virtual welding; Especially in large-sized or multi-channel water-cooled plates, the welding process window is narrow and the yield is difficult to control. - Inconsistent thermal expansion and long-term stress hazards
The difference in thermal expansion coefficients between copper and aluminum is large (copper is about 17 × 10 ⁻⁶/K, aluminum is about 23 × 10 ⁻⁶/K). During thermal cycling, welding or filling materials are prone to stress concentration, which can lead to delamination or structural fatigue in the long run. - Dual requirements for joint filling and thermal conductivity
The gap between the cooling pipe and the aluminum groove needs to be filled, which not only serves as structural reinforcement but also cannot hinder heat conduction. Therefore, multiple performance requirements such as “high thermal conductivity+high strength+low shrinkage” are proposed for the adhesive.
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3、 Solution recommendation: EP 1710 high thermal conductivity epoxy sealant
We recommend using EP 1710 high-performance epoxy structural adhesive to address the problem of bonding and sealing between water-cooled copper tubes and aluminum substrates. It is designed specifically for metal thermal conductivity bonding conditions, balancing thermal management performance and structural reliability.
⭐ Product Highlights:
High thermal conductivity: thermal conductivity coefficient ≥ 1.5 W/m · K, effectively conducting the heat flow between the cooling liquid inside the copper tube and the battery heat, improving heat dissipation efficiency;
Low shrinkage curing: There is almost no shrinkage during the curing process, avoiding stress accumulation at the copper aluminum interface and ensuring uniform and dense filling of joints;
High glass transition temperature (Tg): After curing, the Tg can reach over 120 ° C, ensuring stable operation in high temperature environments;
Excellent heat resistance and aging resistance: meeting the high-temperature working environment of electric vehicles for long-term charging and discharging;
Good adhesion: It has excellent bonding strength to both copper and aluminum, suitable for adhesive reinforcement of interference fit structures.
4、 The application advantages of EP 1710 in battery water-cooled plates
Performance Dimension Performance Description
thermal conductivity ⭐⭐⭐⭐ Quickly conduct heat and reduce cell temperature
adhesion ⭐⭐⭐⭐ Form a stable bonding interface with copper/aluminum
molding shrinkage ⭐⭐⭐⭐⭐ Extremely low shrinkage to avoid stress cracking
Temperature resistance ⭐⭐⭐⭐⭐ High Tg, good heat resistance, suitable for thermal cycling environment
Construction adaptability ⭐⭐⭐⭐ Can automatically dispense and seal, supports batch operations
In the current rapid development of new energy thermal management systems, traditional brazing processes are no longer able to meet the production needs of both reliability and automation. By introducing EP 1710 high thermal conductivity epoxy sealant, not only can the thermal conductivity efficiency and bonding strength between copper pipes and aluminum substrates be improved, but the process can also be effectively simplified and production efficiency can be improved.
If you are looking for high-performance structural adhesive for bonding and filling copper tubes in battery pack water-cooled plates, EP 1710 is undoubtedly a reliable choice. Welcome to contact us for samples and technical support.
Tags: Thermal conductive epoxy adhesive · Thermal conductive adhesive for battery water-cooled board · Structural adhesive with high temperature resistance and high Tg · Copper tube sealant · Copper aluminum bonding structural adhesive
