Week 5 Challenge

1)

The statement is False.

If an aggressive driver is accelerating very rapidly and braking harshly in a city driving, it need high power to meet this scenario. Battery system has low power capacity than ultracapacitor. To obtain this condition, battery pack has to design accordingly. so the battery pack size and cost increases. Ultracapacitor has high power density than battery. So, it take care of peak power under this condition. Suddenn braking results to high regenerative current. So, ultracapacitor can get charge simultaneously.

So, Ultracapacitor is best chioce for an aggressive driver is accelerating very rapidly and braking harshly in a city driving.

2)

Plot for cell voltage Vs energy density:

3)

Plot for cell voltage Vs power density:

The difference for power density and energy density for various battery and UC is given below,

Li-ion types	Specific energy	Specific power
LCO	excellent	worst
LMO	good	good
LFP	low	excellent
NMC	excellent	good
NCA	excellent	good
LTO	low	good
UC	good	excellant

4)

The statement is true.

While charging, Lithium ions move from cathode and get attached to anode. Anode accepts electrons and get reduced. When li-ion pass through electrolyte from cathode to anode, at thae time it react with electrolyte and form a solid electrolyte interface (SEI) layer. This help in avoiding the electron to get contact with electrolyte.