BMS Risk Assessment & Mitigation 2

Question 1

Which failure mode analysis technique is most commonly used to systematically evaluate battery cell-level risks in a BMS?

Accepted Answer

Failure Mode and Effects Analysis (FMEA)

Answer

FMEA is the standard methodology for identifying potential failure modes at the cell and module level and assessing their effects and criticality.

Question 2

A lithium-ion cell exhibits internal short circuit symptoms. Which immediate BMS mitigation action is most appropriate?

Accepted Answer

Isolate the affected cell or module via contactor disconnect

Answer

Contactor disconnect isolates the faulted cell or module, preventing propagation of heat and current that could lead to thermal runaway.

Question 3

What does the term 'Risk Priority Number (RPN)' represent in battery FMEA?

Accepted Answer

The product of severity, occurrence, and detectability ratings

Answer

RPN = Severity × Occurrence × Detectability, and it prioritizes which failure modes require the most urgent corrective actions.

Question 4

During a Fault Tree Analysis of a battery pack, which logic gate is used to represent a scenario where ALL input events must occur for the top-level fault to happen?

Accepted Answer

AND gate

Answer

An AND gate in FTA means all contributing events must be present simultaneously for the undesired top event to occur.

Question 5

Which hazard is introduced when a battery pack is operated at a state of charge above the manufacturer's maximum recommended limit?

Accepted Answer

Lithium plating and increased risk of internal short circuit

Answer

Overcharging beyond the safe SOC window promotes lithium plating on the anode, which can puncture the separator and cause an internal short.

(BMS) Battery Management System Certification Practice Test

(BMS) Battery Management System Certification Practice Test

BMS Risk Assessment & Mitigation 2