SUMMARY
Vehicle electrification has been shown to reduce greenhouse gas emissions while also operating more efficiently than conventional internal combustion engine (ICE) vehicles
Even the most advanced ICE vehicles have an efficiency of less than 50%, whereas an EV has a much higher efficiency of around 90%
While it is not mandatory for EV manufacturers to adopt these standards, only stricter implementation of battery safety policies and standards will reduce rising EV fire incidents
With each passing year, global demand for electric vehicles (EVs) continues to grow. This is largely due to air quality and environmental regulations, as well as rising consumer demand and cheaper energy solutions. Furthermore, significant advancements in EV and lithium-ion battery technologies can be attributed to their growing popularity.
Vehicle electrification has been shown to reduce greenhouse gas emissions while also operating more efficiently than conventional internal combustion engine (ICE) vehicles. The main issue lies with conventional powertrains and the ICE as a power source. Even the most advanced ICE vehicles have an efficiency of less than 50%, whereas an EV has a much higher efficiency of around 85%.
However, as more EVs become operational around the world, the risk of fire incidents is likely to increase. This can harm the lithium-ion battery, posing a risk to the industry and those involved in post-crash operations.
There are various types of lithium-ion batteries, each with its own form factor, cell chemistry, and integration into EVs. There are lithium-ion batteries, for example, with a swappable mechanism, and a few that operate on a charge-and-drive basis. To use lithium-ion batteries safely, it is extremely essential to keep the cells within a defined voltage and temperature range. These limits can be exceeded as a result of an accidental crash or a fault within a vehicle or a battery pack.
A series of fires in electric two-wheelers in recent months have raised concerns about the regulation and safety standards of this rapidly growing segment of the automobile industry. Given the recent fires in electric two-wheelers, the Indian government is expected to issue EV battery standards soon. The detailed policy will address performance testing and manufacturing standards, along with the heat resistance of these batteries.
Meanwhile, the government has tasked responsible authorities, such as the Centre for Fire, Explosive and Environment Safety (CFEES), a laboratory of the Defence Research and Development Organisation (DRDO), with investigating the fire incidents associated with these EVs.
Batteries are the most expensive, largest, and most important component of an EV. The Indian climate and road conditions are harsh, so it’s critical to look after the battery and its charging needs. Manufacturing flaws, such as imperfections and/or contaminants in the assembly process, can also cause thermal runaway. Thermal runaway occurs when a battery cell short circuits and begins to overheat.
Apart from this, the selection of high-quality grade cells and designing a battery pack with the best thermal management systems and an intelligent battery management system (BMS) also play a very significant role in improving the battery safety parameters.
Battery Safety Regulations Currently in Effect
The recent EV-related fire incidents have raised concerns about several aspects of the country’s electric two-wheeler manufacturing process. Whether the battery pack is locally manufactured, assembled or imported, all units are subject to India’s Automotive Industry Standards (AIS) as set by the Automotive Research Association of India (ARAI). Below are some regulatory standards applicable for battery safety under AIS which are currently followed in India:
- AIS 038 REV 1 (2015): Vehicle Safety
This standard specifies the functional safety of electric powertrain vehicles. The tests include protection against electric shock, direct/indirect contact, and water effects, among others.
- AIS 048 (2009): Battery Safety
This standard covers battery safety requirements. It mainly addresses two types of testing, as mentioned below:
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- Electrical Abuse Test (performed at the cell level): Short circuit and overcharge tests
- Mechanical Abuse Test (conducted at the module or pack level): Vibration, mechanical shock, and roll-over tests
A nail penetration test is also performed at the cell level under AIS 048.
According to recent Ministry of Road Transport and Highways (MoRTH) guidelines, this standard (AIS 048) will be phased out beginning in December 2022. As announced by the Ministry of Road Transport and Highways (MoRTH) on December 27, 2021, AIS 156 and AIS 038 Rev 2 standards will become mandatory from December 27, 2022.
- AIS 038 Rev 2 (2020): Battery & Vehicle Safety (For Electric Cars, Buses & Trucks)
This standard addresses a system-level safety approach, in which the battery and vehicle are treated as a single unit. AIS 038 Rev 2 is developed in accordance with GTR 20 Phase 1 (UNR100 Rev3).
- AIS 156 (2020): Battery & Vehicle Safety (For Electric 2-Wheeler, 3-Wheeler & Ecycles)
This standard addresses a system-level safety approach, in which the battery and vehicle are treated as a single unit. AIS 156 is prepared in line with UN R136.
Are These Tests Sufficient?
Much like the UN-certified R136 standard adopted internationally, the AIS-156 standard also places a strong emphasis on testing, shock protection measures, and how a typical battery performs when it is overcharged and over-discharged.
They appear to be very comprehensive in terms of standards. However, they only test one battery pack. Furthermore, the tests do not take into account how well a battery and its management systems perform over time. To accomplish this, OEMs (Original Equipment Manufacturers) must establish a system that exceeds the stringency and rigour of these tests in every way and for all battery packs manufactured.
The Bureau of Indian Standards (BIS) has established standardised parameters for the performance of lithium-ion batteries used in EVs. Two additional battery safety standards are also under development.
This new BIS standard is known as IS 17855:2022, and it has been developed in accordance with International Organization for Standardization (ISO) 12404-4:2018. They were developed with real-life EV scenarios in mind, such as a vehicle in parking, a battery system being shipped, battery operation at low and high temperatures, and so on.
While it is not mandatory for EV manufacturers to adopt these standards, we believe that only stricter implementation of newer battery safety policies and standards will reduce rising EV fire incidents and eventually help the EV market grow.
