Electric Vehicles Are Catching Fire : Daily Current Affairs

Relevance: GS-3: Science and Technology- developments and their applications and effects in everyday life.

Key Phrases: Electric Vehicle, Fire Incidents, Ola Electric, Battery Design, Lithium-Ion Cells, Thermal Runaway, Poor Battery Management System, Import Norms, Organic Solvents, Centre for Fire Explosive and Environment Safety, Solid-state batteries.

Context:

  • The preliminary findings from the government-constituted probe committee on electric vehicle (EV) fires have found issues with battery cells/design in nearly all of the electric two-wheeler (2W) fire incidents in the country, which could put EV two-wheeler manufacturers in a tough spot.
  • The committee was constituted last month in the wake of EV fires and battery blasts in e-scooters belonging to Okinawa Autotech, Boom Motor, Pure EV, Jitendra EV, and Ola Electric.
  • According to sources close to the development, the experts have found defects in battery cells as well as battery design in nearly all EV fires, including the deadly battery explosion in Telangana.

About Li-ion batteries:

  • The energy density of lithium-ion cells used in today’s mobile phones and electric vehicles is nearly four times higher than that of older-generation nickel-cadmium batteries.
  • Lithium-ion batteries use aqueous electrolyte solutions, where ions transfer to and fro between the anode (negative electrode generally made of graphite) and cathode (positive electrode made of lithium), triggering the recharge and discharge of electrons.
  • Despite improvements in technology over the last decade, issues such as long charging times and weak energy density persist.
  • While lithium-ion batteries are seen as sufficiently efficient for phones and laptops, they still lack the range that would make EVs a viable alternative to the internal combustion engine.

Why Electric Vehicles are Catching Fire?

  • According to Exponent Energy, common misconceptions such as the Indian summers and poor thermal management being the reason for (outbreaks of) fire, are not true. The recent fires you see are a result of thermal runaway. Exponent Energy maintained that li-ion cells need to reach a few hundred degrees before having a thermal runaway incident.
  • Most modern batteries automatically switch off around 45-55°C. And even if these thermal-based safety precautions don’t kick in, you won’t see a thermal runaway (fire) because batteries cannot heat themselves up by a few hundred degrees celsius under normal operations. 99% of battery fires are due to short circuits leading to uncontrolled current. This is the only scenario in which cells heat themselves up beyond 100°C.
  • The reason why short circuits happen has also been attributed to poor cell quality, bad battery design, and poor battery management system, where cells aren’t properly managed with the right software intelligence.
  • Manufacturers are not spending enough time designing products, and testing standards prescribed by government bodies may be inadequate to test all real-life situations accurately.

Ways to Minimize the Risk of EV fires:

  • Import norms should be made stricter to ensure that only high-quality parts are brought into the country. The cost will go higher, but that is a part of the process.
  • Battery assemblers in the country should follow high standards – like those set for the automotive industry. A lot of relevant audits and certifications are needed.
  • Integration of battery back with the scooter – this process needs to follow better standards.
  • Avoid charging the EV battery immediately after the EV stops running since the li-ion cells contained in the battery remain hot for some time. Let the battery cool down and then put it on charge.
  • Only use the designated battery and charging cable, designed for the vehicle. Using a local battery that is cheaper can result in damage to the electric vehicle.
  • If it is a detachable battery, avoid placing it in direct sunlight or in hot vehicles and keep it in areas with adequate ventilation. Take care to buy replacement batteries and chargers which match and come from the original manufacturer or an authorized seller.
  • Inspect the battery periodically for damage before use and in case of any defect, stop using it and report it to the manufacturer. If the battery is extremely hot or shows any damage, avoid using it.

Can Solid-State Batteries be an Alternative?

  • Typically, in Li-ion batteries the liquid electrolytes are organic solvents, which are highly flammable. If the current distribution is uneven, filament-like structures called dendrites can form, connecting the two electrodes and causing a short-circuit.
  • The dendrites connect the anode and cathode through the separator, providing a low-resistance path for electron transport, resulting in high self-discharge currents to ignite the flammable electrolyte and leading to explosions. Therefore, dendrite growth is one of the most highlighted issues since it affects the safety of a battery.
  • In contrast, batteries with solid electrolytes do not have the danger of dendrite growth. So, solid-state batteries are less prone to catching fire. Solid-state batteries are primarily driven by efficiency as well as a safety factor. A better battery is one that can pack more energy. Scientists say solid-state batteries can have an energy density. The absence of a liquid electrolyte in all-solid-state lithium batteries simplifies the packaging and reduces dead weight in the battery, resulting in improved energy density.
  • Solid-state electrolytes are typically less reactive than today’s liquid or gel-type electrolytes so they will last longer.

Government Steps:

  • With increasing incidents of electric two-wheelers catching fire, the government has swung into action. Union Minister said that the companies found negligent will be penalised.
  • The Centre for Fire Explosive and Environment Safety (CFEES) had been asked to probe the circumstances that led to the incident and also suggest remedial measures.
  • Government think tank Niti Aayog came out with a draft battery swapping policy for electric vehicles and suggested incentives as well as a rigorous testing protocol for swappable batteries.
  • The Aayog in its draft policy further said all major cities such as state capitals, UT headquarters, and cities with populations above 5 lakh will be covered under the second phase, given the importance of the two-wheeler and three-wheeler vehicle segments in growing cities.
  • The policy seeks a level playing field across business models involving the sale of EVs with fixed or swappable batteries.

Way forward:

  • Conventional lithium-ion batteries are inching towards saturation level in terms of technology advancements.
  • There is a need to develop an alternative solution addressing all restraining factors for the uptake of electric vehicles.
  • Solid-state batteries offer multiple advantages, such as high energy density and safety over conventional liquid lithium-ion batteries.
  • Technological advancements in solid-state batteries are expected to provide improved products in terms of the overall cost of production and performance.

Source: Live Mint

Mains Question:

Q. What are the reasons behind electric vehicles catching fire? Are solid-state batteries be an alternative? Examine (250words).