Best BMS for 24 volt system w/ ~3000 watt inverter?

ZeeMox

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Newbie to the forum here. So my story is that I'm going off-grid because I've got health problems that screwed up my finances and ability to work and I'm looking to be nomadic for a bit while I recover, both physically and financially. I offer this background to explain why I'm jumping in the deep end with very little experience, and I'm hoping this forum can help me out. I'm trying to assemble a 24 volt solar system that can handle up to about 2200 watts of draw with room to spare. I basically want to be able to easily run a microwave or Vitamix for a bit while already drawing a few hundred watts for other stuff. That'll take me off grid easily enough. I've spent the last week or two reading Will's site, watching videos, and finally felt confident enough to order eight 280Ah Eve cells. I'm excited to get started, but I definitely can't afford to blow these cells, so I need to get the right BMS. I'd just go with the recommendations on Will's site, except the Overkill units he recommends are only available at 100 amps, which, from my understanding, will likely shut off if I try to draw as much power as I'd like to. What's a trustworthy BMS that can facilitate the draw I'm going for?

I've also seen it said here that powerful inverters have a resting draw high enough to warrant consideration. I'd say 90% of the time I'm only going to be drawing 600 watts or less. But my inclination is to just suffer the power loss so that I can accommodate max load without issue. Am I on the right track here?
 
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That inverter would work for my purposes, if that's what you're asking?
I was wondering if you had already purchased the Giandel.
I see that you have not.

2200 watts / .85 inverter efficiency / 20 volts low cutoff = 129.411764706 service amps

Have a look at Andy's BMS notes.
 

ZeeMox

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I was wondering if you had already purchased the Giandel.
I see that you have not.

2200 watts / .85 inverter efficiency / 20 volts low cutoff = 129.411764706 service amps

Have a look at Andy's BMS notes.
Thanks for the link, several good options there, but I'm having trouble finding any of the recommended options available in the US. I'll be out on my arse by the time parts arrive from China. I did find some of the Daly BMS on Amazon, though he doesn't have amazing things to say about them. Would this work?
 
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Thanks for the link, several good options there, but I'm having trouble finding any of the recommended options available in the US. I'll be out on my arse by the time parts arrive from China. I did find some of the Daly BMS on Amazon, though he doesn't have amazing things to say about them. Would this work?
The Daly doesn't have much balance capacity.
Should work though.
 

ZeeMox

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The Daly doesn't have much balance capacity.
Should work though.
Thanks, I'll keep that in mind if I can find any other options in the US. Just curious, when you say balance capacity, do you mean maintaining cell balance over time, or can the BMS be used to balance the cells upon assembly?
 
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Thanks, I'll keep that in mind if I can find any other options in the US. Just curious, when you say balance capacity, do you mean maintaining cell balance over time, or can the BMS be used to balance the cells upon assembly?
Balancing the pack over time not initial top balance.
 

ZeeMox

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Balancing the pack over time not initial top balance.
Got it. That seems like a pretty important feature. Do you happen to know if Overkill BMS supports connecting multiple units in series? Maybe it would be better to use 2x12 volt batteries with 100amp Overkill BMS and make a 200amp 24 volt that way
 
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Got it. That seems like a pretty important feature. Do you happen to know if Overkill BMS supports connecting multiple units in series? Maybe it would be better to use 2x12 volt batteries with 100amp Overkill BMS and make a 200amp 24 volt that way
Sorry I can't remember and I would not recommend that.
There is a workaround if you use a stand-alone inverter that supports remote switching.
 
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