Aluminum heat spreader in direct cell contact?

I won't be heating the cells past 45-50 degrees F. The wattage of the heat pads will be around 20 watts total spread across the sides and bottom. I don't want to create hot spots which is why my original questions focus on use of an aluminum plate in contact with the heat pads. I think its clear now that I don't want to put the aluminum plate directly against the cells due to potential for shorting cases together. Placing the heat mats directly on the cells could create a hotter area where they directly touch. May not be an issue but will need some testing. The final thought I'm having is to put heat mats on an aluminum plate but electrically isolate the plate from the cells using a thermally conductive dielectric material. This would apply the heat evenly to a large surface of the cells but remain safe from shorting cell cases.

Anyone doing this?

I'm also planning on using an aluminum plate as a heat spreader for my DIY battery box, also using EVE 304 cells. Under what conditions would you expect the shell cases to short? The cell spec sheet says:



I understand this to mean that each cell is wrapped with 0.11mm of polyethylene terephthalate and the top (and I also assume by looking at the bottom) is 0.3mm of polycarbonate. Is that not adequate insulation to prevent shorting?

The 0.1 mm blue layer is not robust enough, not even close, especially in a mobile application. The cells I've handled don't have the black layer on the bottom.

S Davis said:

I heat the battery box with no direct contact with a 25watt silicone pad and small computer fan. Works great, we got down to 4 degrees this last cold spell.

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what kind of terminal lugs are these? Talk about HD

yoopNreb said:

what kind of terminal lugs are these? Talk about HD

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Those are just cast copper lugs with good quality adhesive shrink wrap. It is 3/0 DLO cable that makes it look larger.