Q. In the context of electric vehicle batteries, consider the following elements:

1. Cobalt
2. Graphite
3. Lithium
4. Nickel

How many of the above usually make up battery cathodes? (UPSC Prelims 2025)
Answer: Only three
Notes: The correct answer is [C] Only three. In the context of Lithium-ion batteries (LIBs), which power most modern electric vehicles, the cathode composition typically involves specific metals, while graphite serves a different role.

• Cobalt, Lithium, and Nickel (Correct): These three elements are primary components of the cathode (the positive electrode). Most EV batteries use formulations like Lithium Nickel Manganese Cobalt Oxide (NMC) or Lithium Nickel Cobalt Aluminum Oxide (NCA). Lithium is the essential charge carrier, while Nickel provides high energy density and Cobalt ensures structural stability and longevity.
• Graphite (Incorrect for Cathode): While graphite is a critical element in EV batteries, it is used almost exclusively as the anode (the negative electrode) material. It stores lithium ions when the battery is being charged.
• Evolution of Cathodes: To reduce costs and ethical concerns related to mining, manufacturers are increasingly using Lithium Iron Phosphate (LFP) cathodes, which do not require Nickel or Cobalt but still rely on Lithium as the base element.

Most commercial high-performance EV batteries today rely on the triad of Lithium, Nickel, and Cobalt for the cathode structure, whereas Graphite remains the industry standard for the anode.