Case Study and Optimization of Low-Temperature Heating for Power Battery Packs

In industrial energy storage sectors, extreme cold is a "performance killer." Low temperatures lead to reduced electrochemical activity and increased electrolyte viscosity, causing a sharp decline in charging and discharging capabilities. As a leading provider of Low-Temperature Battery solutions, CM Batteries has conducted in-depth research into heating technologies to overcome bottlenecks such as slow temperature rise, high energy consumption, and poor temperature uniformity.

1. Testing Methods for Power Battery Low-Temperature Heating The performance of the Battery Thermal Management System (BTMS) is critical for reliable operation in frigid conditions. CMB strictly follows international standards to evaluate heating performance across multiple dimensions.

1.1 Classification of Heating Performance Tests

Testing is primarily divided into low-temperature charging heating and low-temperature discharging heating. These tests are conducted in climate chambers at a standard temperature of -20°C or the minimum operating temperature specified by the manufacturer.

1.2 Key Physical Quantities Monitored

During testing, the following data points are recorded:

Temperature Rise Rate (°C/min): The core metric for heating speed.
Temperature Uniformity: The difference between the highest and lowest temperatures within the battery pack.
Energy Consumption (kWh): Assessing the impact on total vehicle range.

1. Comparative Analysis of Different Heating Methods CMB’s laboratory data compares the effectiveness of external, internal, and liquid heating methods.

2.1 External Heating (Heating Films/Plates)
Mechanism: Attaching heating films or plates to the sides of cells or modules.
Data: A temperature rise rate of 0.8–1°C/min. Heating from -20°C to 10°C takes approximately 30–40 minutes.
Pros/Cons: Low system complexity, but internal temperature differences can reach 5–10°C.

2.2 Internal Heating (Pulse Heating)
Mechanism: Using high-frequency pulse currents to stimulate heat generation within the battery.
Data: A rapid rate of 3–5°C/min. Heating from -20°C to 10°C takes only 6–10 minutes.
Pros: Highest energy efficiency and excellent uniformity (temperature delta within 3°C).

2.3 Liquid Heating
Mechanism: Heating a liquid coolant that circulates through the battery pack.
Data:A rate of 1.5–2.5°C/min. Heating takes 12–20 minutes.
Pros:Best stability and uniformity for large-scale power systems.

1. Performance Degradation and Safety Risks

Without an effective heating system, power batteries at -30°C suffer severe degradation:

Capacity & Power: Charging capacity drops to ~10% and discharge power to ~30% of room-temperature levels.
Lithium Plating: Low-temperature charging risks the formation of lithium dendrites, which can pierce the separator and cause internal short circuits or thermal runaway.

1. Optimization Solutions by CM Batteries To address technical bottlenecks, CM Batteries has implemented the following optimization strategies:

4.1 Integrated Pulse and Film Heating
CMB utilizes high-performance [Low-Temperature Battery](https://cmbatteries.com/project/low-temperature-battery/) cells that support discharge at temperatures as low as -50°C. Our systems can integrate heating films with intelligent BMS pulse logic to ensure rapid recovery from extreme cold.

4.2 Advanced Internal Self-Heating Structure
By integrating customized heating elements (such as Silicone or Kapton heaters) directly within the pack, CMB reduces the heat transfer path and maximizes thermal efficiency.

4.3 Smart BMS Thermal Management
Our proprietary BMS (supporting CANBUS, RS485, and Bluetooth) provides multi-level temperature monitoring. This ensures that the heating function is activated only when necessary, preventing local overheating and consistency deterioration.

1. Future Outlook The future of battery thermal management lies in material innovation and intelligent control. CM Batteries continues to develop next-generation electrolytes and "Vehicle-to-Charger" interconnected heating systems to provide reliable power for medical, industrial, and subsea applications in the world's harshest climates.