The application advantages of Rogers foam in battery thermal management of new energy vehicles are introduced in detail.
The application advantages of Rogers foam in thermal management of new energy vehicle batteries are mainly reflected in the deep matching between its material characteristics and battery system requirements. The following is a detailed analysis from the five dimensions of heat conduction, heat insulation, buffering, sealing and reliability, combined with specific product models and practical application cases:
First, accurate heat conduction control and heat dissipation optimization
1. Efficient heat conduction path construction
Thermal conductive silicone foam (such as BISCO® series) can quickly conduct the heat generated by the battery cell to the liquid-cooled plate or metal shell through high thermal conductivity (some models ≥ 1.0 W/MK). For example, a new energy automobile company uses BISCO® SF-069 silicone foam to support the liquid-cooled plate, and its compression deformation resistance ensures that the cold plate is closely attached to the bottom of the battery, which improves the heat dissipation efficiency by more than 20%.
Flexibility of structural design: foam can be die-cut into special-shaped gaskets to fill the gap between the battery core and the heat dissipation structure and eliminate the blind area of thermal resistance. For example, for the curved surface design of flexible battery, PORON® polyurethane foam provides uniform heat conduction support through microcellular structure.
2. Stability guarantee of liquid cooling system
Stress relaxation resistance: BISCO® SF-069 silicone foam can still maintain more than 90% of the initial supporting force under long-term compression, so as to avoid the heat dissipation failure of liquid cooling plate caused by material collapse.
Lightweight advantage: compared with the traditional spring plate support scheme, the weight of silicone foam is reduced by 40%, and the space at the bottom of the battery pack is saved, creating conditions for improving vehicle endurance.
Second, all-round thermal insulation protection and thermal runaway suppression
1. High temperature barrier and heat spread delay
Flame-retardant silicone foam (such as HT-870) has passed UL94 V-0 certification, which can self-extinguish and form a carbonized layer in an open flame, effectively delaying the spread of thermal runaway between cells. The experimental data show that silica foam with halogen-free flame retardant can prolong the time of thermal runaway diffusion to more than 5 minutes.
Stability in wide temperature range: HT-870 silicone foam can withstand the temperature range of-55°C to 204°C, and can withstand the instantaneous high temperature (such as 180°C) when the battery is charged quickly, while maintaining elasticity in extremely cold environment to avoid heat insulation failure due to embrittlement.
2. Thermal isolation design between batteries
The PCL series of Procell EV Firewall adopts multi-layer composite structure, integrates the functions of pressure management and thermal runaway protection, and delays the spread of open flame through special formula design, thus reducing the use of redundant thermal insulation materials between cells. After 1000 hours at the high temperature of 150°C, the thermal insulation performance of this series is less than 10%.
Third, dynamic buffering and mechanical reliability enhancement
1. Battery expansion compensation mechanism
High-resilience polyurethane foam (such as PORON® 4701 series) provides dynamic buffering when the battery cell is charged, discharged and expanded, and the compression deformation rate is ≤ 10% (tested at 25% compression rate for 72 hours). For example, a square battery module uses PORON® 4701-50 foam as the battery cell spacer, which can absorb 15% of the volume expansion of the battery cell and avoid the risk of tab breakage.
Anti-fatigue performance: the initial resilience of the material remains above 85% after 100,000 compression cycles, which meets the service life requirements of the battery for 8-10 years.
2. Vibration energy absorption
Closed-cell structure design: the closed-cell rate of PORON® foam is ≥99%, which can effectively block vibration transmission. Experiments show that the vibration transmission rate is less than 30% at the vibration frequency of 5-200Hz, which significantly reduces the mechanical stress of battery module caused by road bumps.
Fourth, seal protection and environmental adaptability improvement
1. IP67/IP68 seal
Low compression permanent deformation of silicone foam (e.g. BISCO® SF-069 with 50% compression rate, deformation ≤5% after 72 hours) ensures the sealing performance of battery pack shell in temperature cycle from-40°C to 125 C.. After a battery pack is sealed with silicone foam rubber strip, it has no corrosion after 1000 hours of salt spray test.
Chemical corrosion resistance: the material can resist the long-term corrosion of electrolyte (such as lithium hexafluorophosphate) and cooling liquid (such as ethylene glycol), and the mass change rate is ≤2% after soaking for 1000 hours.
2. Dust and water intrusion
Optimization of micropore structure: PORON® foam achieves the dustproof grade IP5X by adjusting the pore size (20-50μm), and at the same time, the water absorption rate is ≤5% in the humid and hot environment of 85 C/85% RH, so as to avoid the degradation of insulation performance caused by water absorption.
V. Long-term Reliability and Certification Guarantee
1. Aging performance verification
High temperature and high humidity test: after exposure to 85 C/85% RH for 1000 hours, the retention rate of tensile strength is ≥80%, and the flame retardant grade is still UL94 V-0.
Dry-heat aging: PORON® foam lasts for 500 hours at a high temperature of 150°C, and the compression set is ≤15%, which meets the requirements of long-term use of battery packs.
2. Industry standard certification
Compliance: The materials have passed the certification of IATF 16949 quality management system, and meet the environmental protection instructions such as RoHS and REACH.
Customization test of automobile enterprises: For example, a head automobile enterprise conducted a battery pack thermal runaway test on Rogers foam, and the results showed that it could extend the thermal runaway propagation time to more than 10 minutes, far exceeding the industry safety standard of 5 minutes.
VI. Typical application scenarios and schemes
Liquid cooling plate support and heat conduction
Scheme: BISCO® SF-069 silicone foam+thermal conductive silicone grease composite design realizes the dual functions of structural support and efficient heat conduction.
Results: The contact thermal resistance between the cold plate and the battery cell was reduced to below 0.5 kcm/w, and the temperature difference of the battery module was controlled within 2 C..
Thermal isolation and buffering between batteries
Scheme: The laminated structure of Procell™ EV Firewall PCL foam and ceramic fiber can realize pressure compensation and thermal runaway protection at the same time.
Results: The thermal conductivity between cells decreased to below 0.1 W/m・K, and the thermal runaway diffusion rate decreased by 70%.
Sealing and heat insulation of battery pack shell
Scheme: HT-870 silicone foam+aluminized polyester film composite seal, giving consideration to high temperature resistance and reflective heat insulation.
Results: The outer surface temperature of the battery pack was reduced by more than 15°C, and the sealing grade of IP68 was maintained for more than 10 years.
summary
Rogers foam provides a systematic solution for thermal management of new energy vehicle batteries through material performance integration (heat conduction+heat insulation+cushioning+sealing) and design customization (die cutting+composite structure). Its core advantages are as follows:
Safety: through flame retardant design and thermal runaway suppression, the risk of battery fire is significantly reduced;
Reliability: wide temperature range stability and anti-aging performance, ensuring battery life cycle performance;
Efficiency: accurate heat conduction path and lightweight design improve heat dissipation efficiency and cruising range.
With the continuous improvement of battery energy density, the application of Rogers foam in the field of thermal management will be further deepened and become one of the key materials to promote the development of new energy vehicle technology.
