SAE J3277_202404

This technical information report (IR) presents a methodology to evaluate battery pack liquid leak tightness attributes to be used in a production line to satisfy the functional requirement for IPX7, water ingress requirement, and no sustainable coolant leakage for coolant circuits. The Equivalent Channel Method is used as a suggested production leak tightness requirement for a given battery pack design that will correlate and assure that the battery pack meets or exceeds its functional requirement. Obtaining the specific geometry of the Equivalent Channel (EC) for a given battery pack is done analytically and empirically in consideration of the product design limitations. This document is a precursor to J3277-1, which will present the practices to qualify that product leak tightness is equal or better than the maximum allowed EC for that product using applicable and commercially available leak test technologies. This document may be applied to EV and HEV battery packs as tested during production, without harnesses or other accessories installed by the OEM during vehicle assembly. Vehicles using high voltage systems for electrified propulsion are expected to be introduced to the market in increasing quantities. These vehicles include, but are not limited to, plug-in electric vehicles (EV) and hybrid electric vehicles (HEV). These vehicles include Rechargeable Energy Storage Systems, RESS (battery packs) that might be mounted in locations that are exposed to water, either through rain/snow weather conditions or relatively low levels of standing water. Users of these vehicles are anticipated to have some amount of assurance that such water exposure will be unlikely to result in harmful water leakage into a battery pack. Common (and regulatory) functional test requirements for water ingress is per IEC 60529, IPX7 level, which is a destructive test and isn’t applicable for an in-line production testing. This information report offers a method to convert these functional requirements into end-of line nondestructive quality assurance tests of battery packs.