Air leak test on Battery Pack
The battery pack is one of the central elements of the electric powertrain and leak testing is one of the most important tests during its production. Water, moisture and/or dust must not be allowed to enter the battery pack in order not to compromise its functionality and safety; leak testing of the hermetic seal can prevent a possible short circuit of the high voltage components contained in the pack.
The air mass flow leak test method can, in some cases, be used to leak test the entire battery pack cavity and to test the cooling circuit.
The feasibility of air leak testing the battery pack must be technically assessed, considering part volume, reject limit, environmental and part conditions.
The leak test station generally consists of various sealing devices that are able to seal the battery once it is centred and well positioned inside the leak test station. The sealing devices can be automatically retooled to cover different types of parts. The leak test station is generally equipped with an upper retention system able to reduce the "balloon effect" we have on the part when it is pressurised at the test pressure. Reducing the "ballooning" effect when the part is pressurised or depressurised is essential to obtain good performance in terms of cycle time and repeatability.
The test can be carried out by applying a soft vacuum to the part (max. -150 mbar) or by filling the main cavity with air at max. 150 mbar.
Test pressure from -100mbar to +150mbar
Leak rate from 10cc/min to 100cc/min