The requirement changed, not just the part
A door seal on a conventional vehicle has one job - close a gap against weather. A seal inside a battery enclosure has four: keep the ingress rating, survive thermal cycling, hold compression set over the service life, and not contribute to flame spread. Those four pull in different directions, which is why a profile copied from a body seal usually fails in a pack.
Thermal cycling is the part that gets missed
An enclosure heats during charge and cools overnight. That cycle compresses and relaxes the seal thousands of times over the vehicle's life. A compound with good initial elasticity but poor compression set will look fine on the first inspection and leak eighteen months later. Ask for compression set data at the service temperature, not at room temperature.
Flame rating is a material decision, not a coating
Where a seal sits near cells or busbars, the flame rating has to come from the compound itself. Treating the surface afterwards does not survive abrasion or a thermal event. Specify the rating you need with the material grade at the same time - they are the same decision.
Where extruded profiles still win
Charge port lids, service covers, HVAC housings and cable pass-throughs are all irregular shapes with limited groove depth. An extruded profile lets you put material where the compression actually happens instead of filling a standard section. That is the case for a custom cross-section over a catalogue O-ring.
What to send us
The groove drawing, the compression you need to hold, the temperature range in service, and whether the part has a flame rating requirement. If the geometry is not final, send the nearest standard profile you have tested and we will quote both routes.
Profiles for this application
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Working on something like this?
Send the drawing, cross-section, operating temperature and what the seal has to resist. We will tell you whether a stock profile fits or the part needs extruding, and quote both.