Battery Safety in New Energy Vehicles: Key Design of Busbars for Preventing Thermal Runaway – A Comprehensive Analysis

Battery Safety in New Energy Vehicles: Key Design of Busbars for Preventing Thermal Runaway – A Comprehensive Analysis

Our company has been specializd in busbars for many years, designing and implementing various solutions to prevent thermal runaway issues.

In recent years, the sales of new energy vehicles have consistently reached new highs, with market share peaking at 30.4%.

As the adoption of new energy vehicles continues, safety concerns, particularly regarding batteries, have become increasingly prominent. According to authoritative reports, the fire rate of electric vehicles is around 0.03%, slightly higher than the 0.01% to 0.02% of traditional fuel vehicles.

Battery thermal runaway is a direct cause of fires in new energy vehicles, and it is closely related to the design of busbars. Busbars are conductive components used in battery systems, responsible for connecting battery cells and transmitting current. In the electric vehicle battery system, busbars play a crucial role, often made of materials with excellent conductivity, such as copper or aluminum.

Effective prevention of thermal runaway can be achieved through appropriate busbar design and management. Here are some ways:

Material Selection: Choosing the right material is crucial. Copper and aluminum are common choices, with copper having better conductivity and thermal conductivity, though being relatively heavier, while aluminum is lighter but slightly less conductive. We should select the appropriate material based on application requirements.

Cross-sectional Area Design: Ensure that the cross-sectional area of the busbar is large enough to reduce resistance and thermal resistance, thereby minimizing heat generation. Larger cross-sectional areas may be needed in high-current applications to ensure even current distribution.

Heat Dissipation Design: Provide an effective heat dissipation system to ensure rapid heat dissipation from the busbar. This may include fans, heat sinks, cooling liquids, and other cooling devices to maintain the proper temperature.

Even Current Distribution: Ensure that the current is evenly distributed across the entire busbar, avoiding localized high currents that could cause overheating. Optimize current distribution through design and layout.

Temperature Monitoring: Add temperature sensors to the busbar to monitor temperature changes in real-time. Once the temperature exceeds a set threshold, trigger alarms or take automatic control measures, such as reducing current or increasing heat dissipation.

Appropriate Packaging Materials: Use suitable insulation and packaging materials to ensure that the busbar is not affected by external conditions, preventing short circuits and other safety issues.

Flexible Connections: In situations where mechanical vibration or deformation needs to be accommodated, consider using flexible connections, such as flexible busbars. This helps alleviate mechanical stress and improve system durability.

Battery Management System (BMS): Integrate advanced battery management systems to monitor and control the battery's status. BMS can adjust current, temperature, and other parameters as needed to minimize the risk of thermal runaway.

When considering these factors, manufacturers must balance conductivity, thermal conductivity, cost, weight, and other factors to choose busbar materials that suit their design requirements. In high-current applications, such as high-power battery systems in electric vehicles, copper busbars may be more common due to their superior conductivity and thermal conductivity, reducing the risk of overheating. However, some applications may choose aluminum busbars due to cost and weight considerations. In any case, effective heat dissipation systems must be considered to prevent thermal runaway issues.

Our company has been specializd in busbars for many years, designing and implementing various solutions to prevent thermal runaway issues.

After a 10-minute fire test, our products strictly meet the following requirements:

1. Voltage withstand: 3500V DC

2. 60s leakage current < 1mA

3. Insulation performance: 1000V DC, 60s

4. Insulation resistance ≥ 500MΩ


The safety of batteries in new energy vehicles has become the most critical factor for consumers when purchasing cars. To achieve the sustainable development of electric vehicles, technological innovation and standardization are crucial. The industry needs to strengthen cooperation to collectively drive the development of battery technology and busbar design. At the same time, reinforcing regulation and standards will ensure that new energy vehicles are eco-friendly while protecting user safety. Through technological innovation and safety management, we can enhance the reliability of new energy vehicles, making a greater contribution to a clean and green future transportation system. We look forward to seeing more research results on the safety of electric vehicles in the future, promoting the continuous development of the industry.