Introduction

Amid global warming and environmental pollution challenges, nations worldwide are committed to reducing carbon emissions and achieving carbon neutrality. Promoting and applying commercial electric vehicles (EVs) is a vital step towards this goal. Large lithium batteries, as the power source for commercial EVs, play a crucial role in the vehicle's performance, driving range, and lifespan. Due to their high energy/power density, long cycle life, and high stability, lithium batteries are the best choice for driving the development of electric vehicles.

However, lithium batteries are highly sensitive to temperature. At low temperatures (<15°C), the increased internal resistance and reduced reaction kinetics significantly lower the discharge capacity, shortening the driving range. More critically, subzero temperatures can trigger lithium dendrite growth during charging, causing internal short circuits. Uneven temperature distribution within the battery can also lead to inconsistent electrochemical processes, further reducing the battery pack's capacity and cycle life. Therefore, a battery thermal management system (BTMS) with liquid cooling and heating solutions is crucial for ensuring the safety and performance of lithium-ion batteries in electric vehicles.

EVLINK's PTC High-Voltage Liquid Heater

EVLINK has developed various PTC liquid heaters for commercial EVs, actively heating large lithium batteries through coolant. EVLINK's 20kW, 24kW, and 30kW PTC electric heaters are specifically designed for different types of commercial vehicle BTMS. BTMS integrators can transfer preheating strategy information to EVLINK's PTC high-voltage liquid heaters, such as requiring the heater to provide 24kW of heating power and adjust adaptively once a set temperature is reached. EVLINK's PTC high-voltage liquid heaters can adapt based on customer requirements, ensuring efficient and safe battery preheating.

Advantages of PTC Liquid Heaters

• High Power and Voltage: EVLINK heaters can operate at voltages up to 1100V, providing up to 35kW of heating power, making them suitable for large-scale commercial EVs.
• Efficient Preheating: Utilizing efficient PTC elements, EVLINK heaters can quickly heat the coolant to the desired temperature, rapidly raising battery temperature in low-temperature environments to ensure normal EV operation.
• Intelligent Adjustment: The heaters feature adaptive adjustment capabilities, adjusting heating power in real-time based on BTMS feedback, optimizing energy consumption, and improving overall system efficiency.
• Safety and Reliability: PTC materials have self-regulating properties; when the temperature reaches the set value, the resistance significantly increases, automatically limiting the current to ensure the safety of the heater and the battery.

Design Considerations for BTMS

BTMS design must consider various factors depending on the battery integration level. Specific designs should include battery preheating strategies, heat transfer paths and media selection, and battery pack geometry and layout. For external heating systems, optimizing heat transfer fluid and flow channel geometry is key to improving heating efficiency. Internal heating systems require efficient heat generation within the battery to achieve effective preheating.

Comparison of Different Heating Methods

• Resistance Heating:
  • Energy Efficiency: There is some energy loss when converting electrical energy to heat.
  • Temperature Control: Additional control systems are needed for precise temperature control.
  • Thermal Inertia: Resistance heaters continue to release heat after being turned off, making it hard to quickly lower the temperature.
• Induction Heating:
  • Equipment Cost: Induction heating equipment is generally expensive.
  • Electromagnetic Interference: High-frequency operation may cause electromagnetic interference affecting surrounding equipment.
  • Complexity: Requires precise control and design, making maintenance difficult.
• Gas Heating:
  • Safety: There is a risk of gas leakage and explosions.
  • Emissions: The combustion process produces carbon dioxide and other pollutants.
  • Installation and Maintenance: Requires complex piping and ventilation systems, resulting in high maintenance costs.
• Microwave Heating:
  • Penetration Depth: Microwave heating can only heat the surface, making it ineffective for deep heating.
  • Equipment Cost: Microwave heating equipment is expensive.
  • Safety: Preventing microwave leakage is necessary to ensure operational safety.
• Infrared Heating:
  • Uniformity: Ineffective for heating non-uniform materials, potentially causing surface overheating.
  • Distance Limitation: Heating effectiveness significantly decreases with distance.
  • Equipment Cost: High-efficiency infrared heating equipment is costly.

Future Trends and Challenges

As EV adoption and technology advance, EVLINK remains committed to developing more efficient and reliable PTC liquid heaters, providing optimal battery thermal management solutions for commercial EVs. Future research will focus on further enhancing heating efficiency, optimizing BTMS design, and developing new materials and technologies to meet more stringent environmental conditions and power demands.

Conclusion

The promotion of EVs not only reduces pollution and emissions but also lessens dependence on oil. Lithium batteries' sensitivity to operating temperatures makes a thermal management system essential for ensuring high performance, long cycle life, and safe operation. EVLINK's PTC high-voltage liquid heaters, with their high power, high voltage, and intelligent adjustment features, are the ideal choice for commercial EV battery thermal management. In the future, EVLINK will continue to drive the development and application of EV technology.

EVLINK is dedicated to providing the highest quality PTC liquid heater solutions for commercial EVs, helping achieve green travel and sustainable development goals. If you have any questions or needs regarding our products, please feel free to contact us.

EVLINK was established in 2017 with a registered capital of 20 million CNY. It is located at
the junction of Kunshan, Suzhou, and Jiading, Shanghai, covering a factory area of about 5000 square meters.

We have advanced production equipment and a highly qualified management team. EVLINK has passed the
IATF 16949 - automotive industry quality management system certification, and our products have also obtained
various domestic and international certifications, including Emark, EMC, CE, and KC. Our company has over 100
employees, including 20 people in our R&D and engineering department, as well as our hardware and software
teams. Leveraging our extensive technical and manufacturing experience, EVLINK strives to meet market demands.
We are committed to providing our customers with the best AC and DC heaters and offering customized controller services.

      EVLINK Electronics Co.,Ltd is a manufacturer focusing on the design and development of PTC electric heater and its controller.

We has accumulated 10 years of technology and production experience in the field of new energy electric vehicles. In the past 10 years,

we have expanded our main business to the heating solution in new energy electric vehicles, fuel cells, battery thermal management,

energy storage, railway electrification and others.

        Since its establishment, EVLINK has always adhered to the business principle of developing the market with integrity, consolidating the

market with quality, and winning the market with service.It has continuously been innovating and advancing. EVLINK strives to become a globally

renownedPTC heater supplier, maintaining a highly meticulous work attitude.