UN38.3 - Testing for Lithium Batteries
UN 38.3 testing is the United Nations (UN) standard for the safe transport of lithium batteries (both lithium-ion and lithium-metal). It is part of the UN Manual of Tests and Criteria, Section 38.3, and is mandatory worldwide for shipping lithium cells and batteries by air, sea, rail, or road. The tests are designed to ensure that lithium batteries can withstand the environmental, mechanical, and electrical stresses they may encounter during transport without leaking, venting, rupturing, catching fire, or going into thermal runaway.
UN 38.3 testing applies to:
- Lithium-ion cells and batteries (rechargeable, e.g., in phones, laptops, EVs)
- Lithium-metal cells and batteries (non-rechargeable, e.g., coin cells, primary batteries)
Both individual cells and complete battery packs must pass testing. Test applies to prototype and production batteries.
Passing all tests is required before batteries can be certified safe for transport. A Test Summary Report must be available to shippers and authorities.
| Test Name | Description | Procedure | Requirements | Cell Type |
|---|---|---|---|---|
| T.1 Altitude Simulation | Simulates air transport under low-pressure conditions | Cells/batteries stored at a pressure of 1.6 kPa or less for at least 6 hours at ambient temp. | • No leaking, venting, disassembly, rupture, or fire • Open circuit voltage of each cell/battery must not be less than 90% of its voltage immediately prior to procedure |
• Component cells transported separately from battery • All non-rechargeable battery types • All rechargeable battery types |
| T.2 Thermal Test | Assesses seal-integrity and internal electrical conditions | Cells/batteries stored for at least 6 hours at temp of 72 ± 2 °C, then stored for at least 6 hours at temp of -40 ± 2 °C for a total of 10 cycles, then stored at ambient temp for 24 hours (12-hour temp extreme exposure for large cells). | • No leaking, venting, disassembly, rupture, or fire • Open circuit voltage of each cell/battery must not be less than 90% of its voltage immediately prior to procedure |
• Component cells transported separately from battery • All non-rechargeable battery types • All rechargeable battery types |
| T.3 Vibration | Simulates vibration while driving | Cells/batteries subject to sinusoidal waveforms with logarithmic sweep from 7 Hz to 200 Hz and back, transversed in 15 min. Cycle repeated 12 times for a total of 3 hours each for each of the mutually perpendicular mounting positions of the cell. | • No leaking, venting, disassembly, rupture, or fire • Open circuit voltage of each cell/battery must not be less than 90% of its voltage immediately prior to procedure |
• Component cells transported separately from battery • All non-rechargeable battery types • All rechargeable battery types |
| T.4 Shock | Assesses robustness of cells/batteries | Cells/batteries subjected to 3 shocks in the positive direction and 3 in the negative for each of the 3 mutually perpendicular mounting positions for a total of 18 shocks. | • No leaking, venting, disassembly, rupture, or fire • Open circuit voltage of each cell/battery must not be less than 90% of its voltage immediately prior to procedure |
• Component cells transported separately from battery • All non-rechargeable battery types • All rechargeable battery types |
| T.5 External Short Circuit | Simulates external short circuit | Cell/battery heated to stabilized temp of 57 ± 4 °C and then subjected to one short circuit with total external resistance of <0.1 ohm. Short circuit continued for at least 1 hour after cells return to original stabilized temp. | • External temp does not exceed 170 °C • No rupture and no fire during the test and within 6 hours after |
• Component cells transported separately from battery • All non-rechargeable battery types • All rechargeable battery types |
| T.6 Impact/Crush | Simulates mechanical abuse from impact/crush that may result in internal short circuit | Impact: 9.1 ± 0.1kg mass dropped from height of 61 ± 2.5cm at intersection of bar using a frictionless track. Crush: Cell/component crushed between 2 flat surfaces until applied force of 13 ± 0.78kN is reached, voltage drops by 100mV, or cell is deformed by 50% or more of its original thickness. | • External temp does not exceed 170 °C • No rupture and no fire during the test and within 6 hours after |
• Component cells transported separately from battery • Component cells not transported separately from battery |
| T.7 Overcharge | Evaluates ability of rechargeable battery/single cell rechargeable battery to withstand overcharge conditions | Tests conducted at ambient temp for 24 hours with a charge current 2x that of recommended max continuous charge. | • No disassembly • No fire during test and within 7 days after |
• All rechargeable battery types • Rechargeable single cell batteries with overcharge protection |
| T.8 Forced Discharge | Evaluates ability of primary/rechargeable cells to withstand a forced discharge | Each cell force discharged at ambient temp by connecting it in series with a 12 V D.C. power supply at initial current equal to max discharge current. | • No disassembly • No fire during test and within 7 days after |
• Component cells transported separately from battery • Component cells not transported separately from battery |
FAQ:
1. Who needs UN 38.3 certification?
Any manufacturer, importer, or shipper of lithium batteries or products containing them (laptops, EVs, medical devices, tools, etc.) must ensure compliance before shipping.
2. What tests are included?
The regulation defines 8 mandatory tests that must be passed in sequence:
- Test 1: Altitude Simulation
- Simulates air transport under low pressure (15,000 ft).
- Checks for leakage, venting, rupture, or fire.
- Test 2: Thermal Test
- Exposes batteries to rapid and extreme temperature changes (-40°C to +75°C).
- Repeated cycles test tolerance to thermal stress.
- Test 3: Vibration
- Simulates vibration during transport (road/air/sea).
- Batteries must withstand without damage.
- Test 4: Shock
- Simulates mechanical shock from handling/dropping.
- Test 5: External Short Circuit
- Tests resistance to external shorting at high temperatures.
- Test 6: Impact / Crush
- Simulates impact or crushing that could occur in transit.
- Test 7: Overcharge (for rechargeable batteries only)
- Tests response to being overcharged.
- Test 8: Forced Discharge (for cells only)
- Simulates forced discharge when a cell is connected incorrectly.
3. What documentation is required?
A UN 38.3 Test Summary Report is mandatory for shipping. This report confirms the battery has passed all required tests.
4. How often does a battery need UN 38.3 testing?
- New designs or chemistries must be tested.
- Modifications to size, capacity, or chemistry may require retesting.
- Production batches do not usually require repeated testing unless the design changes.
5. What happens if a battery fails UN 38.3?
- The battery cannot be shipped.
- Manufacturers usually redesign or implement additional safety measures and retest.
6. What is the difference between UN 38.3, UL 2054 and UL 1642?
- UL 1642: Focus on individual cells for operational safety.
- UL 2054: Focus on battery packs for operational safety.
- UN 38.3: Focus on transport safety for both cells and packs.
Most manufacturers need both UL and UN 38.3 testing to sell and ship batteries safely worldwide.