Workersbee 700A Liquid-Cooled EV Chargers: Fast, Safe, and Sustainable
Oct 15, 2024
In the previous article, we discussed the importance of liquid cooling technology for DC Fast Charging, which enables electric vehicles to achieve excellent charging experiences. This includes enhancing the charging power limit of High-power charger (HPC), achieving more efficient, energy-saving, and reliable charging.
This article will delve further into the key components of liquid cooling charging, providing insights to help you choose suitable products for the Plug-in EV Charging business.
The main components of the liquid-cooled charging plug include the Coupling Part, Enclosure, Liquid-cooling Assembly Part, Terminal Pin, Sealing Part, and Cable Clip.
Among them, the Liquid Cooling Assembly is the key component of the liquid-cooled charging plug. Due to the existence of contact resistance and connection resistance, the charging plug pin terminal heats up more than other parts like the cable conductor during Rapid Charging, necessitating additional forced cooling. This is where the liquid cooling assembly comes in, establishing a cooling connection through its structure and utilizing the coolant circulation to achieve heat dissipation. The design principle of the liquid cooling assembly is to have a simple structure, easy production, and most importantly, to ensure good temperature rise performance.
The basic structure includes joints, screws, fixing nuts, thermal conductive materials, and seals.
The double-sided joints are responsible for the inflow and outflow of coolant, creating a sealing environment by over-connecting with the liquid cooling tube and meeting the sealing requirements of the coolant. Generally, a simple and easy-to-operate pagoda joint structure is adopted, with a smooth surface to avoid sharp structures causing damage to the liquid cooling tube.
For water cooling solutions, the coolant does not directly contact the metal conductor. The thermal conductive material is located between the terminal pin and the coolant to conduct heat, needing to balance thermal conductivity and insulation.
Compared to ordinary DC cables, Liquid-cooled Cables not only have conductors but also integrate a coolant channel, i.e., the liquid cooling tube. The liquid cooling tube carries the coolant, the conductor wraps around the liquid cooling tube, and the outer layer is insulated. The structure of the liquid-cooled cable determines the internal structure design of the charging plug.
Public Charging Infrastructure has the following standards when choosing liquid-cooled cables:
1. Good flexibility, avoiding stiffness for convenient handling.
2. Good appearance, avoiding excessively thin outer jacket due to the pursuit of a small cable diameter.
3. Low temperature rise of the outer sheath to ensure a good charging experience and safety.
4. Excellent cable and pin welding quality to ensure the reliability of the Liquid cooling HPC.
The Liquid Cooling tube, as the key component of the liquid-cooled cable, plays a crucial role in transferring the coolant and heat. The inner diameter of the liquid cooling tube affects the overall flow resistance. The smaller the inner diameter, the greater the flow resistance, and the lower the efficiency of liquid cooling.
Electric Vehicle Supply Equipment (EVSE) liquid-cooled cables require limiting charging when beyond a certain length - one reason is that longer cables generate more heat, and another reason is that the longer cables have greater flow resistance. However, it also has to consider the lightweight of the cable. The outer diameter of the liquid cooling tube cannot be too large, which requires a balanced solution. In addition, The liquid cooling tube also needs to have a certain strength, sufficient deformation, and toughness.
In EV Ultra-Fast Charging, another important component is the Liquid Cooling System, which consists of a pump, radiator, oil tank, and connecting pipes. The heated coolant is cooled through the heat exchanger and then returned to the oil tank, and the cooled coolant is pumped back to the liquid cooled charging plug through the coolant pump.
Liquid cooling systems can be categorized into automatic control and non-automatic control systems based on whether a charger is needed to control the operation of the pump and heat exchanger. Typically, liquid cooling systems include temperature sensors, liquid level sensors, pressure sensors, and other functional components. For automatic control systems, the charger only needs to provide power and start signals.
Advantages of Workersbee’s liquid-cooled charging cable to business
Workersbee’s CCS2 liquid-cooled charging cable can provide up to 700A of current. The product has passed CE certification and uses user-friendly TPU cable. Its excellent charging performance and high reliability have been highly recognized by our customers. The advantages are mainly reflected in the following aspects:
1. Reliable performance: Carefully designed the structure and material scheme of the liquid cooling tube and liquid cooling cable, using liquid cooling tubes with better chemical resistance, and excellent overall performance.
2. Enhanced user experience: The cable is more flexible and easier to handle.
3. Reliable safety: Effectively control the temperature rise of the outer sheath to avoid safety risks caused by overheating.
4. Solid production craftsmanship: Excellent pin welding quality, strict control of production
5. Cost savings: Applying terminal quick-change technology eliminates the need to replace the entire piece, reducing maintenance costs.
6. Customization options: Workersbee offers customizable liquid-cooled charging cables to meet your specific needs, including logos, different lengths, connector types, and current ratings.
7. Industry compliance: Workersbee's cables comply with industry standards and certifications, ensuring compatibility and interoperability with a wide range of EVs and charging infrastructure.
Conclusion
As a key component of the liquid-cooled charging plug, the liquid-cooling assembly has connectors on both sides responsible for coolant inflow and outflow, connecting to the liquid-cooled tubes carrying the coolant. Heat is transferred via the flow of coolant to the liquid cooling system heat exchanger for dissipation and then circulated back to the liquid-cooled charging plug, maintaining the charging system, including the plug and liquid-cooled cable, at an appropriate temperature to ensure stable transmission of high currents. Only by comprehensively balancing the roles advantages and disadvantages of each component and designing a more reliable liquid cooling technology solution can the performance of liquid cooling be better utilized.
As a pioneer in the EV charging industry, Workersbee has accumulated rich experience in the research, development, production, sales, and service of liquid-cooled charging cables. Our products and technologies have been certified by authoritative testing and have been highly recognized in the market. We look forward to contributing to the development of global sustainable green energy transportation. Contact us to order the latest liquid-cooled charging plugs for CHARGING AHEAD!
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