In a conventional lithium-ion cell, the negative electrode or anode is usually made of:

The correct answer is B, Battery Electric Vehicle. A BEV carries no engine at all; it runs entirely on a traction battery that is charged from an external electricity supply, and it has no tailpipe emissions. The other three abbreviations in the same family are HEV for a hybrid electric vehicle, which has an engine and a small battery but no plug, PHEV for a plug-in hybrid, and FCEV for a fuel cell electric vehicle running on hydrogen.

Option A is an invented expansion, as is option D; a bi-fuel vehicle is one that can run on two fuels such as petrol and compressed natural gas, which is a different idea altogether and not an electric vehicle. Option C is wrong, though the word Bharat does appear in Indian charging standards such as Bharat AC-001 and Bharat DC-001. Learn the four categories as a set, because questions frequently describe one of them and ask you to name it.

The correct answer is A, John Goodenough, Stanley Whittingham and Akira Yoshino. Whittingham built the first working lithium cell in the 1970s, Goodenough found that a lithium cobalt oxide cathode could give a far higher voltage, and Yoshino replaced the dangerous metallic lithium anode with a carbon material, producing the safe, rechargeable cell that was commercialised in 1991. Goodenough, then aged ninety-seven, became the oldest person to receive a Nobel Prize.

Option B names the laureates of the 2000 Chemistry prize for conductive polymers. Option C names the 2013 Chemistry laureates, honoured for computer models of chemical processes. Option D names the 2020 Chemistry laureates, awarded for the CRISPR method of genome editing. The pairing to remember is the year 2019, the subject Chemistry and the three names, since the question is almost always asked in exactly this form.

The correct answer is B, lithium iron phosphate. LFP cells are prized for safety, long cycle life and the absence of cobalt, which makes them cheaper and less exposed to supply disruption; their weakness is a lower energy density, so a pack of the same range weighs more. They are widely used in buses, two and three wheelers and standard-range cars.

Option A is a plausible-sounding invention. Option C has nothing to do with batteries and belongs to rocketry. Option D is also invented. The chemistry to contrast with LFP is NMC, nickel manganese cobalt oxide, which packs more energy into the same weight and so gives longer range, at the cost of more expensive metals, more heat and greater dependence on cobalt from a small number of countries. Examiners like a direct comparison question between the two, usually on safety against energy density.

The correct answer is B, it runs the motor as a generator and returns energy to the battery. When the driver lifts off or brakes, the electric motor is made to work backwards: the turning wheels drive it, it generates electricity, and that current is fed back into the pack. Part of the vehicle's kinetic energy is therefore recovered instead of being lost as heat in the brake pads, which also means the friction brakes wear more slowly.

Option A describes an ordinary friction braking system, which an electric vehicle still carries for hard stops. Option C is not a feature of any electric vehicle; compressed air braking belongs to heavy trucks and railway stock, and works on an entirely different principle. Option D is wrong because during acceleration the battery is supplying energy, not receiving it; energy can be recovered only while the vehicle slows down or runs downhill. The gain is largest in city driving, with its constant stopping and starting.

The correct answer is B, the Ministry of Heavy Industries. The scheme for Faster Adoption and Manufacturing of Hybrid and Electric Vehicles is a demand and manufacturing support scheme, offering incentives that reduce the purchase price of eligible vehicles and funding charging infrastructure, and it sits with the ministry responsible for the automobile and capital goods industries.

Option A, the Ministry of Road Transport and Highways, frames motor vehicle rules, registration and safety standards and has exempted battery vehicles from registration fees, but it does not run FAME. Option C, the Ministry of New and Renewable Energy, handles solar, wind and the green hydrogen mission. Option D, the Ministry of Power, deals with the grid and issued the guidelines for charging infrastructure as a service. A related fact worth holding is that the production linked incentive scheme for Advanced Chemistry Cell battery storage is also with the Ministry of Heavy Industries.