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Benjamin Kegele

Benjamin Kegele

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Facinating

I wondet why it is sealed rather than vented ?!

Next best I guess would be extendung the chill plate to extend under the HVBJB if is doesnt already to maintain a decent temp in that area.
I think its sealed so it does not accumulate any moisture in it. Moisture creates los of isolation corossion.
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Mach-Lee

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The front 'corners' look like good places to drill some little vent holes for cooling ? perhaps with filters to keep out major dust and water ?
That would be a horrible idea, if you drill holes then moisture and water will get in and short out or corrode the battery. Which could cause a fire. Battery has to be airtight for integrity reasons. Moisture and high voltage doesn't mix.

If you've ever seen condensation inside a vented headlight or taillight, that's exactly what you don't want to have happen inside a battery pack.

Plenty of heat is conducted through the bus bars, the issue is very localized heating inside the case of the contactors after they become pitted.

Liquid cooling would be the only possible active cooling method inside the pack, but you can't exactly have a metal cold plate in contact with the charged parts of the contactor for obvious reasons. Bigger contactors will do the trick and is way less complicated, which is what they went with.
 
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dtbaker61

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That would be a horrible idea, if you drill holes then moisture and water will get in and short out or corrode the battery. Which could cause a fire. Battery has to be airtight for integrity reasons. Moisture and high voltage doesn't mix.

If you've ever seen condensation inside a vented headlight or taillight, that's exactly what you don't want to have happen inside a battery pack.

Plenty of heat is conducted through the bus bars, the issue is very localized heating inside the case of the contactors after they become pitted.

Liquid cooling would be the only possible active cooling method inside the pack, but you can't exactly have a metal cold plate in contact with the charged parts of the contactor for obvious reasons. Bigger contactors will do the trick and is way less complicated, which is what they went with.
Ok, that makes some sense... but with proper ventilation/filters in the Hvbjb there wouldnt BE condensation... There are plenty of products that let water vapor thru, but not water droplets.

Wire, insulation, connectors are all fine in open air and wet. The heat from bus bars and contactors would quickly bring that space above dewpoint regardless.

Anyway, it's looking like we will all get the upgraded contactors eventually anyway so it's somewhat of a moot point I was just trying to think of something that could be done short-term in the meantime to prevent problems until we get them
 
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Blue highway

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my question to the OP who was physically there....

IS the HVBJB section (in front of the battery modules) actually 'sealed', or actually have any sensors? I can't imagine why that front section wold be sealed as it would certainly create both positive and negative pressure with temperature changes since is is not fluid filled compartment.

my QUESTION is
Why NOT ventilate the HVBJB ? either to ambient or to cabin at least?
lots of answers to that. You may want to look up the part (relay) that is getting hot. The Relay is sealed and not designed to transfer heat to air. The battery compartment is sealed and not designed to transfer heat to air. Air cooling is not an appropriate solution for this type of device.
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