By: Ritesh Patterson, General Manager, Performance Plastics, Saint-Gobain India
India is a growing market for the automotive industry – as of 2021 it was the 5th largest in the world and is expected to be the 3rd largest by 2030. It is estimated that India will have a stronger and faster adoption of Electric Vehicles (EVs) by 2030 with an annual growth rate of 26%.
Industry Challenges and Effective Battery Pack Solutions
An EV’s efficiency truly depends on its battery and lithium-ion batteries are the most common choice of battery. However, they have the drawback of limited energy storage capacity. This reduces the amount of distance that EV cars can go before needing to be recharged. Since each recharge cycle slightly diminishes the battery’s overall capacity, these batteries have relatively short operational lives and degrade quickly as they age.
To address these existing battery challenges and support the dramatic growth of the industry, significant improvements in EV battery technology are required. Saint-Gobain’s battery pack solutions are driven to deliver EV battery pack protection by providing materials that reduce manufacturing complexity while improving overall battery life.
- Compression pads for Pouch/Prismatic cell
Lithium-ion (Li-ion) battery is a type of rechargeable battery used in electric vehicles (EVs), it is different from the battery used in consumer electronics batteries in terms of chemical chemistry and their high energy density per mass. Three types of Lithium-ion battery cells can be used in EVs: cylindrical, prismatic, and pouch; among these the soft-bodied pouch style is the most popular one because of its highly efficient packaging. In operation, pouch cells are more likely to exhibit swelling due to heat as compared to prismatic cells. In both cases (pouch and prismatic cells), this swelling should be managed to optimize the performance. Products like compression pads help keep the integrity of the pack by limiting the relative motion between the cells in the event of shock or vibration and providing compliance to swelling cells when subjected to force. The foam’s spring-like characteristics present in compression pads provide consistent deflection force over a wide range of compression and temperature — a property called compression force deflection (CFD) and that is where Norseal® foams can contribute to achieving these properties consistently throughout the battery’s life.
- Thermal Runaway Protection Pads (TRP) and Fire-blocking foams (FS1000)
Given the current market occurrences, the marketplace is constantly working to include fire safety aspects in the battery pack. Thermal runaway protection materials can perform a dual purpose of fire mitigation and compression. TRP and FS1000 help minimize fire propagation between cells/modules in a battery pack with their unique property called intumescent – to block flames, hot gases, and smoke in case of fire. They are also airtight for optimal acoustical and thermal insulation. TRPs are soft compressible materials offering fire suppression, thermal insulation, and cushioning whereas FS1000 are soft fire-blocking gasketing foam that is expandable and fire resistant, blocking smoke, air, and water.
- Thermal management with thermal Interface materials
Considering both efficiency and safety criteria, thermal resistance and thermal management are becoming more and more important in the design of electric vehicles (EVs) and their components. It is important to maintain the temperature of the pack as it will be gradually scrutinized as manufacturers and drivers try to get the most from a battery pack. The best way to transmit energy between cooling devices and battery components is by employing thermal interface materials (TIMs). The thermal interface material is a soft, silicone elastomer that is filled with ceramic that is inexpensive, sticky by nature, and performs exceptionally well under compression. Key problems including overheating, electrical shorts, and vibration can be resolved by the multifunctional silicon-based technology i,e from the range of Thermacool.
- Unique gasket materials for IP67 pack sealing
It is significant to keep the battery pack sealed from outside to ensure efficient performance and longevity of an electric vehicle. Battery pack housing options with materials like foam-in-place gasketing, silicone foam rubbers, butyl-coated PVC, and micro-cellular PUR foams seal batteries from the external environment with low compression set and fire-blocking solutions that safeguard the protection of the battery pack.
Impetus from the Government to enhance EV battery performance
The Electric Vehicle sector is at the forefront of sustainable mobility. Albeit in its nascent stage in India, the sector is showing massive growth and attracting great demand among consumers. The government, too, is providing stimulus to accelerate its progress, performance, and infrastructure. One of the key areas of focus is to help combat the existing challenges of EV batteries when it comes to safety and efficiency. The Bureau of Indian Standards (BIS) has, thus, formulated performance standards for EV batteries related to battery cells, battery management systems, onboard chargers, designs of the battery pack, and thermal propagation. These new regulations are said to come into effect from October 1, 2022.
Additionally, following a string of fire incidents in the recent past, efforts are being made to create batteries that are safe and sustainable. For instance, the IPx7 rating test verifies that EVs meet specific requirements to ensure that there are no fires or explosions, and the thermal propagation test verifies the safety of users and bystanders from a vehicle in the event of a thermal runway in the battery system.
Building battery packs that adhere to such rigid testing and performance standards is crucial.
The Road Ahead- Collaborative approach
The need of the hour is for companies with material expertise to work along with EV OEMs and battery pack manufacturers to develop products to meet these applications. Organizations such as Saint-Gobain tape solutions business have been collaborating with EV battery pack manufacturers locally and globally to offer product solutions that ensure enhanced safety and efficiency.
Author: Ritesh Patterson, General Manager, Performance Plastics, Saint-Gobain India
Disclaimer: The views and opinions expressed in this article are solely those of the original author. These views and opinions do not represent those of The Indian Express Group or its employees.