AARC EV & Hybrid Vehicle Processing 3 — Questions and Answers
Question 1: What is the correct procedure for neutralizing a small lithium-ion electrolyte spill at a recycling facility?
- Absorb with dry sand or approved absorbent; do NOT use water (Correct answer)
- Flush immediately with large amounts of water
- Cover with baking soda and leave overnight
- Use a CO2 extinguisher directly on the spill
Correct answer: Absorb with dry sand or approved absorbent; do NOT use water
Lithium hexafluorophosphate electrolyte reacts with water to produce hydrofluoric acid, so dry absorbents are used instead of water.
Question 2: A recycler wants to resell a used EV battery pack for second-life energy storage. Which test is most critical before resale?
- State of health (SOH) capacity test (Correct answer)
- Vibration endurance test
- Chemical composition analysis
- Paint adhesion test
Correct answer: State of health (SOH) capacity test
SOH testing measures remaining usable capacity and determines whether the pack meets the minimum threshold for second-life applications.
Question 3: During EV dismantling, which tool should NEVER be used to cut through suspected high-voltage wiring?
- Standard wire cutters without insulation rating (Correct answer)
- HV-rated scissors with dielectric handles
- Cable cutters rated for the appropriate voltage
- Non-conductive cutting tools
Correct answer: Standard wire cutters without insulation rating
Standard wire cutters are not insulated to HV ratings and create a shock and arc flash hazard when cutting energized HV cables.
Question 4: What does a 'brick' condition mean in the context of a deeply discharged EV lithium-ion battery?
- The battery is physically cracked
- The battery is permanently unusable due to over-discharge (Correct answer)
- The battery has been thermally cured
- The battery cells are fused together
Correct answer: The battery is permanently unusable due to over-discharge
A bricked battery has been discharged below the minimum cell voltage threshold, causing irreversible chemical damage that prevents recharging.
Question 5: Which regulation governs the shipping of damaged or defective lithium batteries by ground transport in the U.S.?
- DOT 49 CFR Part 173.185 (Correct answer)
- EPA 40 CFR Part 261
- OSHA 29 CFR 1910.303
- NFPA 855 Section 4
Correct answer: DOT 49 CFR Part 173.185
DOT 49 CFR 173.185 sets packaging, marking, and documentation requirements for lithium battery shipments including damaged cells.
Question 6: An EV arrives at the yard with a battery management system (BMS) fault code indicating cell imbalance. What recycling implication does this have?
- The pack can be resold as-is with no disclosure
- Individual modules may have degraded cells requiring closer inspection before resale (Correct answer)
- The vehicle must be crushed immediately
- Only the BMS module needs replacement
Correct answer: Individual modules may have degraded cells requiring closer inspection before resale
Cell imbalance indicates uneven degradation; modules must be individually capacity-tested before any second-life or resale application.
Question 7: What is the purpose of the high-voltage interlock loop (HVIL) in an EV battery system?
- To balance individual cell voltages
- To cut HV power automatically when a connector is opened or a cover is removed (Correct answer)
- To cool the battery pack during fast charging
- To communicate battery status to the dashboard
Correct answer: To cut HV power automatically when a connector is opened or a cover is removed
The HVIL is a low-current safety loop that triggers the contactors to open the HV circuit whenever a high-voltage connector is disconnected.
AARC EV & Hybrid Vehicle Processing 3
What is the correct procedure for neutralizing a small lithium-ion electrolyte spill at a recycling facility?