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

Key Phrases: Electric Vehicles, Solid-State Batteries, lithium ion, Highly Flammable, Dendrite Growth, Smaller and More Lightweight, Safer Battery, Advanced Chemistry Cell, Consortium of Institutions, Cost of Production and Performance.

Why in News?

• The move away from liquid electrolytes, which are highly flammable organic solvents.

Context:

• The electric vehicles story is taking off rather nicely in India. Last year, electric two-wheeler sales increased to 2.3 lakh units from 41,050 in 2020-21; for electric three-wheelers the figure was about 1.78 lakh from 88,391; and for electric four-wheelers it was 19,520 units (4,588). However, the dampener to this heartening data is in the form of safety concerns, after a couple of electric bikes caught fire. A prospective EV buyer might be excused for dithering at the doorstep of the showroom.
• Nevertheless, EV batteries catching fire may soon be history. The world is moving towards ‘solid-state batteries’, which, as the name suggests, have only solid components. In contrast, today’s lithium ion (Li-ion) batteries have liquid electrolytes — the medium in which positive ions move from the anode to the cathode.

Why solid-state batteries Safer than Li-ion batteries?

• Typically, in Li-ion batteries the liquid electrolytes are organic solvents, which are highly flammable. If 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. The move to solid-state batteries, though, is primarily driven by the ‘efficiency’ factor rather than ‘safety’. A better battery is one that can pack more energy. Scientists say solid-state batteries can have an energy density of 350 watt-hour per kg, as opposed to 100-260 Whr/kg of the conventional lithium-ion batteries. 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; they will last longer.

Benefits of Solid-State Batteries

There are multiple benefits to solid-state battery technology. like

• Smaller and More Lightweight: Energy density measures the amount of energy a battery contains proportional to its weight. Solid-state batteries are said to be capable of delivering 2.5 times more energy density of current lithium-ion tech. This tremendous increase in solid-state batteries’ energy density means that they will be far smaller and lighter. Electric vehicles also have much to gain from this technology as they could get much more range with less weight and space in battery storage.
• Faster Charging Times: Solid-state batteries can work at very high rates of power. Research suggests that they may be able to recharge 4-6 times faster than current technologies safely.
• Safer Battery Experience: Liquid electrolytes found in lithium-ion batteries are extremely volatile and highly flammable. These electrolytes also mustn’t be exposed to air. Solid-state batteries contain no liquid parts and will not have this volatile component.
• Additionally, these batteries will require fewer safety systems than lithium-ion batteries do. Eliminating additional electronics can contribute to smaller, lighter-weight battery packages, which further enhances solid-state batteries’ energy density.
• Much Easier to Manufacture: Working with a volatile liquid that cannot be exposed to air is a huge challenge that could be completely eliminated with solid-state battery technology. A solid electrolyte could enable much faster production that uses less material and energy.

WHY IS IT DIFFICULT TO MASS PRODUCE SOLID STATE BATTERIES?

• Carmakers and technology companies have produced solid-state li-ion battery cells one at a time in a lab, but have been unable so far to scale that up to a mass production.
• It is hard to design a solid electrolyte that is stable, chemically inert and still a good conductor of ions between the electrodes. They are expensive to fabricate and are prone to cracking because of the brittleness of the electrolytes when they expand and contract during use.
• Currently, a solid-state cell costs about eight times more to make than a liquid li-ion battery, experts say

INDIA’S BATTERY PUSH

• The Government of India is working on a blueprint for a project of around 4,000 MWh of grid-scale battery storage system at the regional load dispatch centres that control the country’s power grid, primarily to balance the vagaries of renewable generation.
• Reliance Industries Limited has announced plans to set up an Energy Storage Giga factory; state-owned NTPC Ltd has floated a global tender for a grid-scale battery storage project.
• The Ministry of Heavy Industries issued a request for proposal for setting up manufacturing facilities for Advanced Chemistry Cell (ACC) battery storage in India.

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.
• Major OEMs such as Toyota, BMW, Honda, and Hyundai are investing in technology development by collaborating with R&D institutes, battery material manufacturing companies, and battery manufacturers. However, the fully commercialized solid-state battery-based electric vehicles are expected to be launched by 2025.

Source: The Hindu BL

Mains Question:

Q. How will solid-state batteries make electric vehicles adoption more economical and safer? Examine (250 words).