Hi everyone!
In the past I’ve built 3S30P total of 100Ah battery pack inside a tool box for father’s trolling motor, it works well to this day.
But he wants more range, so I’ve decided to build larger one, but at the same time up the series count to 4 so at the lower discharge he wont get defeated by some wind.
So 4S and around 150Ah, assuming 3Ah 18650s it’s 200 cells.
Obviously it doesnt have to be exactly this many cells, plus minuts 20 is ok, or maybe even different cell size.
I don’t really want to DIY it much this time, I want to use off the shelf enclosure with dedicated cell holders and precut nickel strips so it’s all easy.
Any suggestions?
Thanks!
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Peli case. Come in all thinkable sizes. Also watertight.
That was my first go to idea, but that is still to much DIY, want something where almost no guess work or designing is required.
Idk, what do you mean designing? You build the pack and plop in in there. Cell holders can be configured in all possible arrangements.
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Peli case is not all flat and square inside, need to fix the cell holders in there somehow, and also would need to use those “lego style” holders to get the fitting size and thos are weaker than solid one.
I’m thinking something like that:
… just a bit bigger
Are you talking about the rounded edges? Because thats all that is in there afaik. Also, if putting together those lego style holders is too much DIY for you, why not contact a battery builder here on the forum and have them build the whole thing for you, case included? Thats way you have zero work to do. 
I also really don’t like these cheap cases you posted, they are made from really thin ABS mostly, break easily and are not waterproof in any way. I think hardly anyone on here ever used something like this.
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I was talking more about rigidity of such holders.
Yes I’ve used them for smaller one but I think bigger batteries should use something more solid.
oh okay gotchu. Well imo those would be fine, as the battery isn’t subjected to great forces if I understand your scenario correctly, and also those holders aren’t meant to strengthen the batteries structure anyway, they are meant to keep the cells apart. Structural integrity is added with the welds and ultimatively the case.
Obv. they do something too, but I think you can buy this stuff in meters and just cut one sheet to size to fit your pack. Tough the biggest battery holder sheet I’ve see so far holds 50pc., after that its lego.
Google/Amazon search diy junction box
No, no, no…never. Not one tiny ounce of force should ever be applied to any of the welds during use of the pack.
The pack can be bounced all over (though not great either) but it must do so as one solid unit. Every time a weld gets tugged at even a little bit you start to fatigue that weld. Over time that increases its resistance and eventually the weld(s) fail.
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I should have make clear that you should not put the welds under force. 
My bad. But if you weld metal to something, you tend to add structural integrity to something.
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Often that is true…
But when the weld is a mm or two in size with almost no penetration or strength I’m not sure anyone can argue for enhanced structural integrity here. 
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Depends on the amount, but yeah, bottom line, you’re right, should have made that clear.
Straight up, just use a cooler.
Might be I didn’t express my intentions fully:
- I’m busy with electronics at work, don’t have too much will to get any biggers projects in my spare time
- Off the shelf solution so that it looks somewhat professional, not like peli case bolted shut with screws
- I live abroad and should anything go wrong I won’t be able to work on it
- Where I live I can’t do much DIY, not really allowed to use power tools etc.
I’m surprised there is no good enclosure systems out there, I thought first reply I get is 10 links and would have too much to chose from lol.