Week 5 Challenge

1. Consider a scenario where an aggressive driver is accelerating very rapidly and braking harshly in a city driving. Is battery better a choice to supply power than UC in this scenario?

a)True

b)False

Why?

b) False.

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.
• 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 rapid acceleration and deceleration very frequently. Because it have more power density to abosrb that kind of pressure or it provides that amount of pressure which requires the driver at the time of rapid acceleration.

2. Consider the following components.

1) Lead acid battery 2) Nickel cadmium battery 3) Nickel Metal hydride battery 4) Lithium ion (specify chemistry) battery 5) Ultra Capacitor

Note: In case of a range of energy density, take the average value for the plot.

Create a plot with energy density on the X Axis and cell voltage on the Y axis.

Comment on the capabilities of these batteries based on the plot created.

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.

The values of energy densities of different batteries and cell voltage are shown in the below table and also the same is represented in the X-Y plot shown below.

Battery	Cell Voltage	Energy Dnesity
Lead acid battery	2.1	25
Nickel cadmium	1.2	50
Nickel Metal hydride	1.2	140
Li-ion	3.6	260
Ultracapacitor	2.6	206

In that plot the the different types of battery cell voltages and their energy density has been plotted. In that plot the highest cell voltage is the lithium ion cell and the minimum cell voltage is the nickel cadmium and the nickel metal hydride. The high energy density also the lithium ion and the lowest energy density is lead acid battery.

3. For the above-mentioned components on the same plot (retain the previous plot) created in the previous

Create a plot with power density on the X axis and cell voltage on the Y axis.

Battery	Cell Voltage	Power Density
Lead acid battery	2.1	150
Nickel cadmium	1.2	75
Nickel Metal hydride	1.2	1000
Li-ion	3.6	340
Ultracapacitor	2.6	496

In that plot the the different types of battery cell voltages and their energy density has been plotted. In that plot the highest cell voltage is the lithium ion cell and the minimum cell voltage is the nickel cadmium and the nickel metal hydride. The high energy density also the nickel metal hydride and the lowest energy density is nickel cadmium battery.

I have attached the xl file for that pls see.

4. Consider the following scenario:

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.

1. True
2. False

Answer:

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 statement is ture.