Battery technologies (Li-ion, NiMH, Lead-acid) – MCQs – EE

1. Which of the following is the most commonly used battery type in modern electric vehicles (EVs)?
(A) Lead-acid
(B) Nickel-Metal Hydride (NiMH)
(C) Lithium-ion (Li-ion)
(D) Zinc-carbon

2. The electrolyte used in a lead-acid battery is:
(A) Potassium hydroxide
(B) Sulfuric acid
(C) Sodium chloride
(D) Ammonium sulfate

3. The nominal cell voltage of a Li-ion battery is approximately:
(A) 1.2 V
(B) 2.0 V
(C) 3.6 V
(D) 4.5 V

4. Which battery type has the highest energy density among common rechargeable batteries?
(A) NiMH
(B) Lead-acid
(C) Li-ion
(D) Nickel-cadmium

5. The negative electrode in a lead-acid battery is made of:
(A) Lead dioxide (PbO₂)
(B) Sponge lead (Pb)
(C) Graphite
(D) Nickel oxide

6. The positive electrode in a NiMH battery is composed of:
(A) Nickel oxyhydroxide (NiOOH)
(B) Cadmium
(C) Lead dioxide
(D) Graphite

7. The negative electrode in a NiMH battery consists of:
(A) Hydrogen-absorbing metal alloy
(B) Lead
(C) Lithium
(D) Nickel oxide

8. Which of the following batteries is environmentally least friendly due to lead content?
(A) NiMH
(B) Li-ion
(C) Lead-acid
(D) Nickel-cadmium

9. The typical nominal cell voltage of a NiMH battery is:
(A) 1.2 V
(B) 3.6 V
(C) 2.0 V
(D) 4.0 V

10. Which battery type suffers from a memory effect?
(A) Li-ion
(B) NiMH
(C) Nickel-cadmium
(D) Lead-acid

11. The main advantage of Li-ion batteries is:
(A) High energy density and low self-discharge
(B) Low cost and long cycle life
(C) High weight and large size
(D) Can be overcharged safely

12. The main disadvantage of Li-ion batteries is:
(A) High self-discharge rate
(B) Low voltage
(C) Thermal runaway risk
(D) Low energy density

13. The electrolyte in NiMH batteries is typically:
(A) Sulfuric acid
(B) Potassium hydroxide (KOH)
(C) Lithium salt
(D) Sodium chloride

14. The energy density of lead-acid batteries is typically around:
(A) 30–50 Wh/kg
(B) 100–150 Wh/kg
(C) 200–250 Wh/kg
(D) 300–400 Wh/kg

15. The energy density of Li-ion batteries ranges between:
(A) 30–50 Wh/kg
(B) 60–100 Wh/kg
(C) 150–250 Wh/kg
(D) 400–500 Wh/kg

16. Which battery type is most suitable for renewable energy storage (e.g., solar backup)?
(A) Lead-acid
(B) NiMH
(C) Li-ion
(D) Zinc-air

17. The cycle life of a typical Li-ion battery is about:
(A) 100–200 cycles
(B) 300–500 cycles
(C) 1000–5000 cycles
(D) 10,000 cycles

18. A lead-acid battery is most commonly used in:
(A) Mobile phones
(B) Electric vehicles
(C) UPS and automotive starter systems
(D) Laptop computers

19. The self-discharge rate of a Li-ion battery per month is approximately:
(A) 10–20%
(B) 5–10%
(C) 1–2%
(D) 20–30%

20. The internal resistance of a battery affects:
(A) Voltage drop and heat generation
(B) Battery size
(C) Energy density
(D) Electrode material

21. Which of the following is a rechargeable battery?
(A) Alkaline battery
(B) Zinc-carbon
(C) Li-ion
(D) Silver-oxide

22. The state of charge (SOC) represents:
(A) Percentage of charge remaining in a battery
(B) Voltage level
(C) Temperature of electrolyte
(D) Type of electrolyte used

23. Which factor significantly affects battery lifetime?
(A) Depth of discharge (DoD)
(B) Ambient temperature
(C) Charge/discharge rate
(D) All of the above

24. The nominal voltage of a 12V lead-acid battery consists of how many cells?
(A) 3 cells
(B) 4 cells
(C) 6 cells
(D) 8 cells

25. Overcharging a Li-ion battery can lead to:
(A) Capacity increase
(B) Thermal runaway and fire
(C) Electrolyte freezing
(D) Reduced voltage output

26. Which battery chemistry has the lowest cost per kWh?
(A) Lead-acid
(B) NiMH
(C) Li-ion
(D) Solid-state

27. The main cause of capacity fade in Li-ion batteries is:
(A) Electrolyte evaporation
(B) Growth of solid electrolyte interface (SEI) layer
(C) Over-discharge
(D) Low temperature

28. NiMH batteries are commonly used in:
(A) Hybrid electric vehicles (HEVs)
(B) Smartphones
(C) Laptops
(D) Drones

29. The specific energy of Li-ion batteries is approximately:
(A) 30–50 Wh/kg
(B) 100–265 Wh/kg
(C) 10–20 Wh/kg
(D) 400–500 Wh/kg

30. Which battery type requires regular maintenance due to electrolyte loss?
(A) Li-ion
(B) NiMH
(C) Lead-acid (flooded type)
(D) Solid-state