Why altitude simulation is critical for battery safety ? In the global supply chain, Lithium primary and secondary cells are frequently transported via air cargo. While modern aircraft cargo holds are pressurized, They are not maintained at sea-level pressure. At cruising altitudes, The pressure drops significantly. For a sealed battery, This creates a dangerous pressure differential: the internal pressure remains high while the external environment becomes a partial vacuum.
If a battery casing is weak or the sealing is defective, This pressure difference can lead to electrolyte leakage, rupture, venting, or even fire. To mitigate these risks, International safety organizations enforce strict testing protocols known as altitude simulation. Altitude test chamber from Wewon Environmental Chambers Co., Ltd. is engineered specifically to replicate these low-pressure conditions, Ensuring your products meet the rigorous demands of UN 38.3 (Test T.1) and IEC 62133
| At the heart of Wewon’s altitude chamber system is a robust Dual-Stage Rotary Vane Vacuum Pump (such as the Hokaido 30 series). While the standard requires 11.6 kPa, The systems are capable of reaching significantly lower pressures (down to 0.5 kPa or lower), providing a stress test margin that ensures absolute reliability for high-stakes aerospace applications. This rapid evacuation capability ensures you reach the target test pressure quickly, maximizing lab throughput. | High-Performance Vacuum Control |
| Both UN 38.3 and IEC 62133 require monitoring the battery’s status during the test. Altitude (Low Pressure) Test Chamber from Wewon Tech is equipped with a sealed feedthrough flange | Real-Time Data Monitoring via Feedthrough Flanges |
| Function: This specialized port allows signal transmission wires to pass from the interior of the chamber to external data loggers without breaking the vacuum seal. | |
| Benefit: You can monitor open circuit voltage and temperature in real-time, ensuring that if a voltage drop occurs (indicating an internal short), the test can be stopped immediately. | |
| The standards explicitly state that altitude testing must occur at Ambient Temperature (20℃ ±5℃). Our chamber design ensures thermal stability, preventing temperature fluctuations that could skew test results or mask battery failures. | Ambient Temperature Stability |
| Equipment Model | WEW-ALT-64 (Small) | WEW-ALT-125 (Medium) | WEW-ALT-300 (Large) | WEW-ALT-1000 (Walk-in) |
| Internal Dimensions (W×D×H) | 400 × 400 × 400 mm | 500 × 500 × 600 mm | 800 × 650 × 600 mm | 1000 × 1000 × 1000 mm |
| External Dimensions (W×D×H) | 650 × 625 × 1350 mm | 700 × 850 × 1550 mm | 1400 × 1300 × 1700 mm | 1500 × 1550 × 2150 mm |
| Volume (Test Room) | 64 Liters | 125 Liters | 300 Liters | 1000 Liters |
| Pressure Range (kPa) | Ambient ~ 5.0 kPa (Adjustable) | Ambient ~ 5.0 kPa (Adjustable) | Ambient ~ 5.0 kPa (Adjustable) | Ambient ~ 0.5 kPa (Adjustable) |
| Pressure Fluctuation | ≤ ±5% | ≤ ±5% | ≤ ±5% | ±0.1kPa (≤2kPa); ±5% (2~40kPa) |
| Depressurization Time | ≤ 30 min (Ambient to 1 kPa) | ≤ 30 min (Ambient to 1 kPa) | ≤ 30 min (Ambient to 1 kPa) | ≤ 30 min (Ambient to 1 kPa) |
| Pressure Recovery Rate | Adjustable (e.g., < 10 kPa/min) | Adjustable (e.g., < 10 kPa/min) | Adjustable (e.g., < 10 kPa/min) | < 10 kPa/min (Controlled Recovery) |
| Temperature Function | Ambient / Monitoring (Optional) | -20°C ~ +150°C | -40°C ~ +100°C | Ambient / Real-time Monitoring (PT100) |
| Controller Type | Programmable Color Touch Screen | Programmable Color Touch Screen | Programmable Color Touch Screen (7″) | 7′ Color Touchscreen (USB/RS485) |
| Vacuum Sensor | Electronic Pressure Transducer | Electronic Pressure Transducer | High Precision Pressure Transducer | INFICON PSG50 (High Precision) |
| Interior Material | SUS#304 Stainless Steel (3mm) | SUS#304 Stainless Steel (3mm) | SUS#304 Stainless Steel (Reinforced) | SUS#304 Stainless Steel (Heavy Duty) |
| Exterior Material | Cold Rolled Steel (Powder Coated) | Cold Rolled Steel (Powder Coated) | Cold Rolled Steel (Powder Coated) | Cold Rolled Steel (Powder Coated) |
| Observation Window | Tempered Glass with Mesh | Tempered Glass with Mesh | Multi-layer Tempered Glass with Mesh | Large Tempered Glass with Safety Mesh |
| Feedthrough / Cable Port | Standard DN40/50 or Customized | Standard DN40/50 or Customized | Standard DN40/50 or Customized | DN16 ISO KF / DN25 ISO KF Blind Flanges |
| Power Supply | AC 220V, 50/60Hz, Single Phase | AC 220V, 50/60Hz, Single Phase | AC 380V, 50/60Hz, 3 Phase 5 Wire | AC 380V, 50/60Hz, 3 Phase 5 Wire |
| Installed Power (Approx.) | 2.2 kW | 8.5 kW | 14.0 kW | 24.0 kW |
| Net Weight (Approx.) | 85.0 KGS | 120.0 KGS | 350.0 KGS | 1580.0 KGS |
To certify your batteries for transport and consumer use, Your altitude chamber must meet specific technical parameters derived from international regulations. Such as testing standards: UN 38.3 & IEC 62133. Altitude test chamber from Wewon Environmental Chambers Co., Ltd. is not just a standard vacuum box; It is a precision testing instrument designed to exceed the 11.6 kPa threshold required by the standards｜UN 38.3 Test Report for Lithium Battery Pack
| The Requirement: Test cells and batteries must be stored at a pressure of 11.6 kPa or less for at least six hours at ambient temperature. This is the global benchmark for the transport of dangerous goods. Almost every lithium battery shipped by air must pass this test. | 1. UN 38.3 Test T.1: Altitude Simulation |
| The Pass Criteria: The battery must show no mass loss, no leakage, no venting, no disassembly, no rupture, and no fire. Additionally, the open circuit voltage must remain not less than 90% of its pre-test voltage. | |
| This standard applies to nickel and lithium systems used in portable devices. For Nickel Systems (Section 7.3.7): Cells are placed in a vacuum chamber at . The pressure is gradually reduced to 11.6 kPa (simulating an altitude of 15,240 meters) and held for 6 hours. | 2. IEC 62133: Safety for Portable Applications |
| For Lithium Systems (Section 8.3.8): The standard refers directly to the transport tests defined in the UN Manual of Tests & Criteria (UN 38.3). |
| ● | Q: What is the pressure requirement for the UN 38.3 altitude test? |
| ● | A: The chamber pressure must be maintained at 11.6 kPa or less. This pressure simulates an altitude of approximately 15,000 meters (50,000 feet). |
| ● | Q: Does the altitude test require temperature control? |
| ● | A: The test is conducted at ambient temperature (20℃ ±5℃). While active heating/cooling isn’t strictly required by the basic altitude test, maintaining stable ambient conditions is mandatory. |
| ● | Q: How long does the IEC 62133 low-pressure test take? |
| ● | A: The test duration is 6 hours at the target low pressure. |
The altitude (low pressure) test chamber from Wewon Environmental Chambers Co., Ltd. is designed for UN 38.3, UL 1642, IEC62133, and other standard testing requirements. It can quickly achieve a low-pressure storage state for samples. It can automatically control the test cycle, monitor pressure changes within the chamber throughout the process, and automatically terminate the test. When using the altitude test chamber from Wewon Environmental Chambers Co., Ltd. , The workflow is streamlined for efficiency and compliance:
| Measure the mass and voltage of the battery. Ensure the battery is fully charged according to the manufacturer’s specifications (typically 1st cycle or after 25/50 cycles depending on the specific UN 38.3 requirement). | 1. Pre-Test Check: | Altitude Test Procedure: |
| Place the cells or batteries inside the chamber. Connect signal wires through the feedthrough flange to your external voltmeter. | 2. Loading Note: | |
| Seal the door and activate the vacuum pump. The controller will automatically reduce internal pressure to 11.6 kPa (or your custom setpoint, e.g., 0.5 kPa). | 3. The Evacuation: | |
| According to the UN 38.3 T.1 request, Most of time, The system maintains this low-pressure state for a minimum of 6 hours. | 4. Duration Hold: | |
| The altitude low pressure chamber from Wewon Tech is re-pressurized to ambient levels. The batteries are removed and inspected for: | 5. Recovery Check: | |
| Mass Loss: Must be within limits (e.g., <0.1% for batteries >5g).｜Visual Integrity: No leakage, venting, or rupture.｜Voltage Retention: Must be of initial voltage. |
Connects the test sample inside to external instruments. Critical for monitoring optical communication interruption or attenuation under extreme conditions.
Rapidly evacuates air to create a precise low-pressure state, accurately simulating high-altitude aerospace environments down to specific kPa levels.
Coordinates refrigeration units and solenoid valves to precisely control internal temperature, simulating the freezing conditions found at high altitudes.
Features individualized locking nuts for absolute sealing, allowing optical fibers to penetrate chamber walls without leaking pressure or vacuum.
