QuantumScape solid-state battery may be the future of EVs

QuantumScape solid-state battery may be the future of EVs

Subject: Science and tech

Section: Msc

Context:

• QuantumScape, a U.S.-based company, has developed a solid-state battery prototype that marks a significant advancement in electric vehicle (EV) technology.

Details:

• This battery retained 95% of its capacity after 1,000 charging cycles, potentially enabling an EV to cover a total mileage of over 500,000 kilometres with a single charge range of 500-600 kilometres.
• This performance surpasses the current industry target for solid-state battery development, which is about 700 charging cycles with a maximum capacity loss of 20%.
• The tests, conducted by Volkswagen’s battery company PowerCo, suggest this technology could address many challenges facing current EV batteries, such as cost, safety, capacity, charging time, and durability.
• Solid-state batteries differ from traditional lithium-ion batteries by using a solid electrolyte instead of a liquid one, eliminating many safety and performance issues associated with the latter.
• This new type of battery offers improved temperature tolerance, is non-flammable, and does not leak, making it potentially more suitable for varied climates.
• Solid-state batteries have been a research focus for 40 years, with recent breakthroughs overcoming long-standing challenges in cycle life, thermal stability, and current density.
• QuantumScape’s solid-state lithium-metal cell, notable for its anode-free design and ability to be produced in layers for series cell production, represents a leap forward in energy density and manufacturing scalability.
• Major automotive companies like Volkswagen, BMW, Toyota, and Hyundai are investing in solid-state technology, with launches of solid-state battery EVs anticipated around 2025.

About Solid State batteries:

• These batteries use solid electrodes and a solid electrolyte, instead of the liquid or polymer gel electrolytes found in lithium-ion or lithium polymer batteries.
• Solid-state batteries can provide solutions for many problems of liquid Li-ion batteries, such as flammability, limited voltage, unstable solid-electrolyte interphase formation, and poor cycling performance and strength.
• In the charging & discharging cycle, ions transfer to and fro between the anode (negative electrode generally made of graphite) and cathode (positive electrode made of lithium).

Advantages of the solid-state battery technology:

• Higher cell energy density (by eliminating the carbon anode)
• Lower charge time (by eliminating the need to have lithium diffuse into the carbon particles in conventional lithium-ion cells)
• Ability to undertake more charging cycles and longer life.
• Improved safety and Lower cost.
• Increase the capacity of EV batteries.

Source: DTE