EV Batteries and Charging Systems

A battery cell consists of

• Two primary elements

• Three primary elements

• Four primary elements

• None of the anwers

Answer explanation

A battery cell consists of three primary elements: two electrodes (positive and negative) immersed into an electrolyte

A battery labeled 100 Ah at C5 rate. What is the discharge current?

• 20 A

• 0.05 A

• 500 A

• 5 A

Answer explanation

100 amp-hour capacity at 5 hours discharge rate (discharging current 100/5=20 A)

Unit of specific energy is

• Kg/Wh

• Wh/Kg

• Wh

• Kg

Answer explanation

Nominal Battery Voltage (V) x Rated Battery Capacity (Ah) / Battery Weight (kg) = Specific Energy or Energy Density (Wh / kg)

The net cycle efficiency has a maximum in the

• High range of SoC

• Lower range of SoC

• Middle range of SoC

• Zero

The specific power of a chemical battery depends mostly o

• Battery current

• Battery capacity

• Efficiency

• Battery’s internal resistance

The typical estimated life of a Lithium-Ion battery is

• 300 to 500 charge cycles

• 200 to 500 charge cycles

• 100 to 500 charge cycles

• 400 to 500 charge cycles

Answer explanation

One charge cycle is a period of use from fully charged, to fully discharged, and fully recharged again

Who is the biggest EV battery manufacturers in India?

• Amara Raja Batteries

• TATA AutoComp Systems Limited

• Exide Industries

• LG Energy Solution

One Ah equals to

• 100 C

• 4000 C

• 1000 C

• 3600 C

Answer explanation

One ampere of current represents one coulomb of electrical charge, i.e. 6.24×10¹⁸ charge carriers, moving in one second

The Practical capacity of battery is always

• Much lower with theoretical capacity

• Much higher with theoretical capacity

• Both are equal

• Slightly higher

The stored electrical potential energy in a 12 V, 100 Ah battery is

• 1.23 MJ

• 4.32 MJ

• 5.32 MJ

• 6.85 MJ

Answer explanation

•1 Ah is equivalent to 3,600 C, while 1 V refers to 1 J (joule) of work required to move 1 C charge from the negative to positive electrode. Therefore, the stored electrical potential energy in a 12 V, 100 Ah battery is (12)(3.6 ×10 5 ) J = 5.32 MJ