If you’re using a single 3/4” good quality ply and you have it spring compressed at 10 psi (550 lbs total), you will bend the board. You either haven’t noticed, don’t have correct compression or don’t have enough months on it. That goes for CATL or Eve cells. I’m running 8 cells in a fixture (6 fixtures.) From a cool day, low charge to a hot day full charge there is a 3/16” difference in fixture length (end plate travel) that means each cell is expanding .023” despite being under compression. Would the wood bend be less with 4 cells? Perhaps, but the pressure is close to the same IF it’s sprung with reasonable spring travel and not a rigid.If your cells are bending 3/4 ply in a 4s configuration, either you have junk cells that expand way more than they should or are pre-compressing the heck out of them.
If it were one string of 16s, that might be a different story.
spiffy!!!!I drilled and tapped the edges of the heat sink and used 1/2" (12mm) aluminum angle to mount the BMS. That also gives me a bit more heat dissipation through the aluminum compression frame.
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This was a lot of work. I can’t see any isolation on the sides and if you haven’t left room for it, not to worry. Aluminum can be hard anodized. Hard anodizing is one of best insulator known for its thickness and incredibly durable. The anodizer needs to know what alloy the parts are made of and I would recommend that you callout for having all taped holes masked.I drilled and tapped the edges of the heat sink and used 1/2" (12mm) aluminum angle to mount the BMS. That also gives me a bit more heat dissipation through the aluminum compression frame.
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