Abstract: Method for leak testing a finished battery cell using a leak test system comprising a vacuum chamber and a detecting and measuring instrument, the method including positioning the cell in the vacuum chamber, sealing the vacuum chamber, starting a vacuum creation phase in which the pressure inside the vacuum chamber is decreased, starting a stabilization phase in which gases and/or vapors deriving from parts and/or substances inside the cell leak from the cell, starting an acceleration phase in which an auxiliary gas is fed into the vacuum chamber pushing the gases and/or vapors leaking from the cell towards the detecting and measuring instrument, and detecting the leak rate by means of the detecting and measuring instrument. In the acceleration phase the pressure inside the leak test system is raised, thereby increasing the flow of the gases and/or vapors leaking from the cell towards the detecting and measuring instrument.

Abstract: Leak testing system (100) and method for leak testing a finished battery cell, comprising a vacuum chamber (4), a vacuum pump (6), a detecting and measuring system (1) to detect gases and/or vapors escaping from the cell, the gases and/or vapors deriving from parts and/or substances inside in the cell, and a capillary element (2) which connects the detecting and measuring system to the vacuum chamber and through which the gases and/or vapors leaking from the cell flow. The system further comprises heating devices adapted to heat at least one of the components of system, thereby making the system substantially memory-free.

Abstract: A method of leak testing at least one "main" cavity (1) formed in a body (2), involving filling the main cavity with a test gas (6) at a determined pressure (PO). The leakage pressure variation (15, 16) in the main cavity is measured while reducing the pressure inside the main cavity in steps (dp.sub.n) by means of a controllable valve (12). The various values of leakage pressure variation, are compared with equal values being representative of a part that is leaky and with values that become smaller from one measurement to another being representative of the presence of at least one secondary cavity communicating with the main cavity via a seepage path (4) having high head loss. The two cavities taken together are possibly non-leaky.

Abstract: The invention relates to a method for producing a guiding device for flexible materials in which an element, representing the actual guide passage to be produced, is made with the aid of a malleable material; the element is positioned in a mould which has the general shape of the outer contour of the device to be produced; a resin is cast inside this mould and onto the element, and the malleable material constituting the inner element is then eliminated with the aid of an agent which has no action on the resin.