Automotive interview question on battery pack? Most commonly asked one

All QuestionsCategory: Electric VehicleAutomotive interview question on battery pack? Most commonly asked one
Chetan Shidling Staff asked 2 months ago
2 Answers
Chetan Shidling Staff answered 2 months ago

This is the most common entry-level interview question in the Automotive Industry. What will be the C rate of the 12-volt lithium battery pack? Let’s consider that it’s a 4-volt cell with a rated capacity of 2Ah. Well, first connect 3 cells in series to achieve 12 volts. The formula to calculate the C rate will be load current/battery capacity. Let’s consider the load current as 2 Amps, then the C rate will be 2/2 = 1 C. If the load current is 4 Amps, then the C rate will be 4/2 = 2 C and the discharging time will be (1/Crate)*60 i.e., (1/2)*60 = 30 minutes. Now comment below, if the rated capacity of a cell is 4Ah and load current is 2 Amps. what will be the C rate and time?

Chetan Shidling Staff answered 2 months ago

This is the most common entry-level interview question in the Automotive Industry. What will be the C rate of the 12-volt lithium battery pack? Considering that it’s a 4-volt cell with a rated capacity of 2Ah. Well, your answer should be, first connect 3 cells in series to achieve 12 volts. The formula to calculate the C rate will be load current/battery capacity. Let’s consider the load current as 2 Amps, then the C rate will be 2/2 = 1 C. If the load current is 4 Amps, then the C rate will be 4/2 = 2 C and the discharging time will be (1/Crate)*60 i.e., if the C rate is 2, then it’s (1/2)*60 = 30 minutes (It takes 30 minutes time to discharge). Now comment below, if the rated capacity of a cell is 4Ah and load current is 2 Amps. What will the C rate and time be?