Week 5 Challenge

Q.1..?

1. False

Because,

Solution: Battery is not a better choice in the given driving scenario.

Condition: The driver is driving aggressively. Very rapid accelerating and braking (deceleration) take place in the driving.

Battery:

• A battery converts chemical energy to electrical energy and it is reversible in chemical reactions.
• They have low power density
• The battery charge/ Discharge process is relatively slower.

Ultra-Capacitor:

• Ultracapacitors are also known as supercapacitors.
• The source of energy is electrical energy.
• They are a very high energy density.
• As the Ultracapacitors are bigger capacitors, they store a large amount of electrical charge than the chemical batteries.
• They are having high power density.
• Ultracapacitors undergo a quick charge and discharge rate.

Result:

As per the above comparison between battery and ultracapacitor, it is understood that Ultracapacitors are more suitable for vehicles that accelerate and decelerate very frequently.

Q.2...?

Energy Density: It is the measure of how much energy a battery contains in proportion to its weight. This measurement is typically presented in watt-hours/kilogram. The higher the energy density, the longer the runtime.

Lead Acid batteries:

Lead-acid batteries have relatively low energy density.

Nickel-Cadmium Battery:

Nickel Cadmium has a much higher energy density compared to lead-acid batteries.

Nickel-Metal Hydride Battery:

Ni-MH batteries can have two to three times the capacity of NiCd batteries of the same size, with high significance and also much less than lithium-ion batteries.

Lithium-ion battery:

Lithium-ion batteries have a high energy density.

Ultracapacitor:

Energy density is more in ultracapacitors compared to capacitors.

Q.3...?

The power density of the above set of batteries is as shown below.

Battery name	Power density (W/Kg)	Cell voltage (V)
Lead-acid battery	180	2.1
Nickel Cadmium	150	1.2
Nickel Metal Hydride	1000	1.2
Lithium-ion	340	3.6
Ultracapacitor	496	3.5

Q.4...?

True. The number indicated as 1 is a -ve electrode.

Lithium-ion batteries generate DC power by utilizing chemical reactions.

• During discharge, lithium ions from the -ve anode move through the electrolyte to gets intercalate the +ve cathode.
• During charging, electrons move from anode to cathode in the external circuit.
• Electrons flow to balance the cell voltage.
• During the electrochemical process, the anode is -ve and the cathode is +ve.
• At the first time charging, the lithium-ion from the cathode gets attached to anode and it forms the inseparable layer on the anode.
• A solid Electrolyte Interface (SEI) is formed at the anode. Anode gets decomposed if it comes in contact with the electrolyte. SEI protects the anode.

Summary:

A battery has just been manufactured in the industry and has been connected to a charger for the first time. The electrode marked as (1) in the picture below is the negative electrode. this is true