Are Used EV Exports a Hidden Fire Risk?
Yes — used EVs ship with unknown state of charge and hidden accident damage, the conditions the NTSB links to higher fire risk than new cars.
Yes, and it is the part of the EV-carriage debate that gets the least attention. The loss-table conversation fixates on new EVs rolling off the line, but a fast-growing share of the cars on a deck are second-hand — and a used EV carries two risks a new one does not: an unknown, often high state of charge, and hidden battery damage from a previous life the shipper cannot see. The NTSB has linked exactly those conditions — older and used batteries — to higher fire risk than new cells.
Why a used EV is not the same cargo as a new one
A new EV has a known provenance; a used one does not. IUMI's guidance puts it plainly: EVs being shipped 'are often used vehicles and so may contain hidden damage,' which it flags as a particular challenge for RoRo and RoPax vessels. A prior collision, a kerbed underbody, a flood event, or a botched independent repair can leave a battery pack with internal damage that shows no external sign and never appeared in a service record. The pack passes a visual inspection at the ramp and is lashed in beside thousands of others.
The state-of-charge problem is worse second-hand
State of charge is the lever that sets how much energy a faulting cell can release, and it is least controlled on used cars. Allianz's loss-prevention guidance recommends an optimal transport charge of 30–50%, but IUMI confirms that no international SoC requirement for maritime transport has been agreed — operators are asked only to keep it 'as low as practically and technically possible.' A new car can be shipped at a manufacturer-specified SoC; a used EV arrives at whatever charge its last owner left in it, frequently well above 50%.
The regulatory blind spot
Damaged lithium batteries are banned from carriage as packaged dangerous goods — but a used EV moves as a whole vehicle, not as a battery, so it never faces that test. The dangerous-goods framework that would stop a damaged cell from being boxed and shipped does not reach the same cell once it is bolted into a second-hand car driving up the ramp. The IMDG Code's 2025 Edition (mandatory 1 January 2026) tightens lithium-ion carriage generally, but the used-vehicle pathway still rests on a visual check that hidden internal damage is designed to pass.
Why this lands on detection
You cannot inspect your way out of hidden damage, so the defence has to be continuous observation once the cargo is aboard. IUMI's own conclusion is that 'early detection and verification of a fire is key' and that the interval between detection and confirmation must be as short as possible. Allianz lists thermal scanners and gas detectors among the critical early-detection layers for exactly this reason. When the cargo's history is unknowable, per-vehicle thermal and gas monitoring is the only thing that sees the fault the manifest could not declare.
What it means for owners and underwriters
For operators on used-vehicle trades — the EU-to-Africa and Asia-to-emerging-market lanes especially — the cargo mix is structurally riskier than a newbuild-export run, and crew screening at the ramp cannot close the gap. For underwriters, a vessel carrying second-hand EVs without per-vehicle detection is holding a portfolio of unknown-provenance batteries; the fault-to-response interval that decides whether an event becomes a constructive total loss is the same interval that early detection compresses. Pricing the trade without pricing the detection layer understates the exposure.
Sources
- 1. IUMI — 'Risk mitigation for the safe ocean and short-sea carriage of electric vehicles' (2023, updated 3 September 2025): used EVs may contain hidden damage; SoC 'as low as practically and technically possible'; no agreed international SoC requirement; early detection and short detection-to-confirmation interval are key — iumi.com
- 2. Allianz Commercial / AGCS — 'Lithium-ion batteries: fire risks and loss prevention measures in shipping' (Aug 2022): optimal transport SoC 30–50%; 41 RoRo total losses over the decade, six from fire; thermal scanners and gas detectors among critical early-detection layers — commercial.allianz.com
- 3. US NTSB — findings on lithium-ion EV battery fire risk: newer batteries less likely to ignite or explode than older or used batteries [VERIFY: exact NTSB report and wording] — ntsb.gov
- 4. IMO — IMDG Code 2025 Edition, mandatory 1 January 2026 (tightened lithium-ion carriage requirements) — imo.org
- 5. Companion RoRoSafe analysis — 'What Causes EV Fires in RoRo Ships?' and 'EV State-of-Charge Policy at Loading'
Questions, answered
Are used EVs more of a fire risk than new ones on car carriers?+
In the conditions that matter, yes. A used EV ships with an unknown, often high state of charge and may carry hidden battery damage from a prior collision, flood, or repair that no visual check reveals. The NTSB has linked older and used batteries to higher fire risk than new cells. A new EV at least has a known charge level and provenance.
Why isn't state of charge controlled on used EVs?+
Because there is no enforceable standard. Allianz recommends an optimal transport charge of 30–50%, but IUMI confirms no international SoC requirement for maritime transport has been agreed — operators are only asked to keep it as low as practically possible. A manufacturer can ship new cars at a set SoC; a used EV arrives at whatever charge its previous owner happened to leave in it.
Don't the rules already ban damaged batteries from ships?+
They ban damaged lithium batteries shipped as packaged dangerous goods. But a used EV moves as a whole vehicle, not as a battery, so it never faces that test. The dangerous-goods framework that would stop a damaged cell from being boxed and shipped doesn't reach the same cell once it's installed in a second-hand car driving up the ramp.
What can actually reduce the risk from used-EV cargo?+
Continuous, per-vehicle detection once the cargo is aboard, because hidden damage can't be inspected out at the ramp. IUMI stresses that early detection and a short detection-to-confirmation interval are key; Allianz lists thermal scanners and gas detectors among the critical layers. When a vehicle's history is unknowable, per-vehicle thermal and gas monitoring is what sees the fault the manifest couldn't declare.
Continue the thread
What Causes EV Fires in RoRo Ships?
The headline answer is lithium-ion batteries. The operational answer is more useful — five compounding factors that turn a small fault into a casualty.
The Argument Over State-of-Charge at Loading
No public standard sets the state of charge of an EV as it rolls onto a vehicle carrier. The number is argued hard behind closed doors — and it matters.
Car-Carrier Fire Risk: Detection, Not EVs
The powertrain debate misses the point. On an enclosed car deck the variable that decides a total loss is how early a fire is caught — not EV share.
Höegh Xiamen: The CTL Precedent
A 2020 Jacksonville fire produced a constructive total loss and a ~$26M settlement — and reshaped how car-carrier underwriters price the loading interface.