Weird question: Necessary to screw in HV modules?

What's the purpose of "double stick"? What's the other side sticking to?

 

You misunderstand his intention. He isn't saying to mount them all like that, just to use the tape on the leaky module to insulate it from the case. The screws DO NOT ground the module to the case, at least not on purpose.

 

Go oem

 

Try goop will work great . I've done two modules with it . Next time my buddy builds a battery I may have him goop all the modules down Don't forget they're squeezed now too and bolted down on the squeeze tab so it's not like they're going anywhere. Next time I may just eliminate the screws that go into the modules because that seems to be a wear issue somewhat. Working easily foo bar by just one extra twitch of the quarter drive wrench or torque wrench whatever you're using retourqing old removed screws. There's something to that You have to be very careful especially when the screw can pierce the module and let electrolyte run out.

 

I don't like the execution of that concept. Those screws help keep the rather heavy HV pack from smacking the inside of the metal case in the event of a crash.

IF a module (or two) had an isolation leak through the metal screw insert , BUT had no electrolyte leakage, THEN I could see omitting a screw or two and insulating the insert from the case.

However, getting rid of all those screws seems like "lazy man's job insurance". He don't want the possibilty of that type of fault (+ it's easier to sticky things down than to flip the pack over and run all those little screws into place. I don't have tons of battery refurb experience, but I don't think that kind of isolation failure is very common.

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Well a long strip of that gray double-sided Scotch stick tape is rated for pretty stout weight when you're talking about it 24-in strip times two or slightly longer That's exactly what I have one or two modules with the nonsense touching the screw but not leaking yet but I'm covered just for future reference seems to me the double-sided stick tape would work well because when you're racked and squeezed your rack that's doing the squeezing is bolted down by four bolts at each corner of the business is it not? I think it is in my generation too but I'd have to look and then all that is in case in a case so in a crash if the modules move 2 in and smack the top of the case well if it's an accident like that the car is probably going straight to the junkyard so maybe no worries we're already fixing a leak of high DC voltage to the 12 volt chassis of the car nobody's been shocked and we're still driving the car resetting it when it codes with the cheap scanner clearing the codes twice. The battery guy will be here in about an hour with another setup and hopefully no leakage yet to screw holes or liquid touching the screw holes or whatever the heck is going on.

 

I was wondering why that was taking so long weird three times holy. I'm more interested in hearing about how the cables running from the battery up to the inverter would get destroyed? You'd have to Steve McQueen the car right bounce it against the asphalt destroy the trays the plastic ones running up the car scrape the plastic off the cables? That's another total car it seems like you'd be destroying good portion of the floorboard right?.

 

If you are not using the module mounting screws, you are setting yourself up for catastrophic failure. The clamping device for the battery modules works because the mounting screws fasten the modules to the base plate to keep the module assembly straight, keeping the middle from buckling upward, downward or whatever direction when the modules try to swell under load. Similar to how an I-Beam stays straight even under massive load. The flanges keep the web straight and the web keeps the flanges straight. Individually, each piece is weak as hell, together they're incredibly strong. Yet, with enough load, and insufficient bracing at the middle, the center will buckle outward and cause instant failure. I'm sure everyone is familiar with the coke can experiment. Where you can stand a can on a table, put a lot of weight on the top and it holds just fine? Then poke the side of the can and it will instantly fold. The same can be true with the HV battery pack, except the screws attaching the modules to the base are what is maintaining the straightness. No screws will allow the pack to bow at high load. Once that pack starts to buckle? Say goodbye because the black clamp bars will not save it. They're only good for the tension stress. Missing a few screws is no big deal, since the modules interlock together, using none of them? That's crazy and shows a lack of understanding of the forces exerted on a battery pack and mechanical integrity. A HV battery builder doing this? Absolutely ridiculous and should probably be limited to changing batteries in a flashlight.