Thanks so much for all the helpful info. I’ve scratched the 18650’s off my list. Would the 40t be a reasonable choice in the 21700 size form? Less output but same Mah, don’t think I would be able to utilize all the output of either battery but when considering range in the equation both cells give me the same WH’s. Would 18640batterystore be a reliable place to purchase cells? Or is there somewhere I should consider? I’m going to try ordering them out of the states and have them shipped up here to Canada, they are literally 40% cheaper compared to Canadian prices. I’ll get dinged some duty no doubt, but should still save me a few hundred bucks
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Same date code I am testing. 
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For lower discharge current levels, below about 7A or so, the ultra-high capacity “energy” cells like the 50G, 50E, M50A, can run efficiently. This lets them for longer than “power” cells like the P42A that are best used at higher power levels.
Once you get up to about 10A the delivered Wh of energy for both is the same.
The P42A is a good choice at any level though. It’s just that there can be slightly better choices at lower power levels.
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oh … that’s interesting
Are you planning some construction or are you just coming to help us mere mortals?
I’ve always wanted to set up a board but, for now, I’m just hanging out and learning what I can and helping where I can.
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@luis99945 or anyone else who has the iphone SmartBMS app, what do I search in the app store to find it?
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finally finished balancing last night, took 10 days, heh
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This is definitely the right way to approach this hobby, and its admirable! Too many folks show up and jump in early, and then get disillusioned when it doesnt work out how they want. Keep reading and learning, and if you have questions dont hesitate to ask! Honestly we all owe you tons when it comes to knowledge 
if you were to make a thread titled “Mooch’s first build - HELP” or something like that, folks here would be lining up around the block to help you out 
And this is why we all love you 
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Is XiaoxiangBMS Cost 7USD
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I was about this far off 
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I was one of those people in a hurry and ended up spending a lot of money and finishing my build like 3 years later
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Same, except my build is total shit rn and I’m definitely giving it a revamp 
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So I’ve been thinkin…
Which connector ist best suited for connecting the chargeport to the battery?
The JST RCY/ BEC i wouldn’t use for over 3A but the size is perfect.
The XT30 is nice for high amp chargers but is too big to fit through the mounting hole of a good 5.5*2.1mm barrel port…
Problem is that some of my customers can’t properly solder and I wan’t to supply my batterys completely ready made for ease of install.
sooooo does anyone know a ~10A/ ~15A capable connector with a max. diameter of 11mm?
(it also should be halbj proof, meaning polarity can’t be reversed like with bullet connectors)
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Don’t supply barrel ports, start using gx-16 3pin or something then the XT30 will fit fine.
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I’m using them since most chargers come with barrel ports and they’re small and nice to mount in any enclosure. Using a non standard chargeport will just make everything more complicated…
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Yeah I agree, I don’t like using the JST in anything higher than 3-4A.
An XT30 is way overkill for most people’s charging capabilities, but it’s better to be above. If you switch the normal connector orientation and use the male xt30 with the barrel, it’s much easier to shove that through the enclosure hole.
Also interested to see if anyone has a better connector that I’ll work with barrels.
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Are bullet connectors unacceptable? I’m assuming it’s not being mentioned because they vibrate loose or something so they’d be a bad choice
