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Are there any real thrustworty +100A BMS?

Frank in Thailand

making mistakes so you don't have to...
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Daly sucks.
That's a good start to begin with.

There are too many people ordering Daly after @Will Prowse "set and forget" video, with all the drama in hundreds, thousands of posts here on the forum.

Personal I like the active balancer BMS from ICGOGOGO, fist batch was bad quality.
I heard they improved.. apparently, not that much.

Chargery is "quiet" lately..
Does that mean it works??

Batrium will work for sure, an S16 +200A setup will cost about $1000,-

Electrodamus, positive news again, sadly just up to 24v..

Seriously.
If one would be buying +/- $5000, worth of LiFePO4, what BMS would you advise and why?

Without (functional) BMS the battery is not protected for over or under charge, that could easily cost a huge part of the $5000,-

A BMS that stops, would mean no electricity...

Sure.. DIY..

Just imagine you are not home to fix but your mother needs to do.
(Mine is close to 80, and never was able to setup VCR to record her favourite)

What will work, continue to work and is as easy to fix (if ever needed) as...
Your mother or grandma should be able to..

Preferably not the price tag of Batrium :)

Daly, for the thousands of posts, is clearly out and should not be advised at all.

Daly, dumb version under 100A did make a good name for a good reason.
Sadly they aren't able to bring that level of quality to the +100A models.
 
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I have no experience with any BMS other than the Overkill Solar one. I set mine up and haven't needed to tweak it. My only complaint about it is that the Android App is a little goofy at times, but it does work. It's the interface, not the functionality. Not showing the temperature in fahrenheit is dumb. It can show that on the Apple version.
 
@HRTKD
Thanks for the feedback.

I changed the post a little +100A BMS.

Normal household have peaks about 7.5-10kw.
A powerful blender easy take 2000w
Water boiler 1000w, thats just making breakfast :)

Personally I don't like to have the need to walk around the house before I start any powertool, being vacuum cleaner, blender, oven, grinder, welder, or air-conditioning.
It most likely won't be running all at once, several will.
7500 watt isn't a that crazy spike.

At 48v (or 51.2 if you like) that's 150-200A.

And that is where the trouble seems to start.

Many people are happy with their 100A or less BMS.
Going higher....
That seems to be really tricky.

Possibly much to do with the mosfets that are used to turn on/off contact.

I'm in the process of building DYIBMS that using contactor/relays and can do 800mA balancing per cell.

I go slow but steady..
So far so good.
It requires soldering and uploading firmware, not for all people.
After that, it's web based.

Besides Batrium the most stable BMS I have heard of so far, above 100A.

Overkill solar BMS I read also many positive response. Sadly their top is 100A
 
I have a 4s2p 12v battery setup, so two BMS, each 120 amp. Net result is 240 amp throughput, assuming everything works like it should, which it has so far. The same can be done with 48v.
 
I have a 4s2p 12v battery setup, so two BMS, each 120 amp. Net result is 240 amp throughput, assuming everything works like it should, which it has so far. The same can be done with 48v.
Sure, one could stack, like the electrodamus. (There not the amps but the number of cells)

S16, LiFePO4 +/- 50kwh Powerwall..
Price for cells today about $5000,-

2 different devices to monitor and setup...
Not my first idea of advice.
Making workaround is always possible.

Would you advise that as best solution?
 
Daly, dumb version under 100A did make a good name for a good reason.
Sadly they aren't able to bring that level of quality to the +100A models.
I haven't tried this but... Why not buy a 16S, 20A Dumb Daly (< $20) and use it to control the coil of a 500A contactor that has a 48v coil. For instance a KiloVac EV200 (NO) with 32-95V DC coil. Draws only 0.03A @ 48V to hold it closed. (I assume there are cheap knock offs available.) BMS only carries coil load. Not programable, but should prevent disaster. You could add your favorite active balancer in parallel. Each component does only One thing, very simply.
 
Not programable, but should prevent disaster. You could add your favorite active balancer in parallel. Each component does only One thing, very simply
Good idea. If it is not programmable it might create conflicts if it is used with a balancer. I prefer to turn off the balancing on my BMS when using an active balancer.
 
I'd probably use the JK-BMS active balancer with BT, which could be controlled I can't believe the built in passive balancing of 30ma on the Daly would interfere.
 
I'm amazed people have a tough time with daly bms. I own around 20 (a whole box of LTO/LiFePO4/NMC bms) and I have only killed one (I mixed up two of the balance wires). And it was my fault.

I set and forget daly bms on my systems and friends, never an issue. Need to short out p- and b- to turn it on, but that's all. They have worked great for me.

How do you guys kill yours?

But I absolutely despise daly customer service.
 
If you are considering Batrium at $1000 consider Orion Jr. at $600 plus contactor. I have had good luck with Orion over 5 years.
You have a link of Orion Jr.?

To be clear, I'm not considering anything (yet).
I have active Balancer (2, for 2 different battery sets, one 2A for my cosmetic bad 48* 152Ah and one 1A for 32x 280A.

And building the DIYBMS from Stuart Pittaway.
With contactors/controllers and heatsink to boost the already masive 800mA to 1.5A if needed...

But...
Many people ask me for advice.
And while I really think the DYIBMS is the best out there that's affordable, it's a sh!t load of work.
Probably because I'm old :)
Too small....

For quality it comes close to the Batrium, at $3,- per cell module, $10 for controller + contactors...

Batrium is too expensive to advise to most people.

Orion Jr., Might already get in acceptable range.

How much do to want to spend to protect the investment???
And when you do, what really works?

With dropping LiFePO4 prices, the capacity just goes up, most peop don't spend less, just buy more Ah.
 
I'm amazed people have a tough time with daly bms. I own around 20 (a whole box of LTO/LiFePO4/NMC bms) and I have only killed one (I mixed up two of the balance wires). And it was my fault.

I set and forget daly bms on my systems and friends, never an issue. Need to short out p- and b- to turn it on, but that's all. They have worked great for me.

How do you guys kill yours?

But I absolutely despise daly customer service.
Have you tested any smart Daly lately?

If I'm correct the "smart" BMS now have 3 different hardware versions, all need different parts or software to set, if "programmable" at all...
That much changes since the release, 6 months ago...
You don't do if it's quality to start with.

Making the field do QA for you and not sending free of charge the updated (hardware) models to customers as the current version is prone to defects is bad.
Bad business.
You build and sell a protective layer and don't give a -peep-if it functional or not, or that there are known timebombs in the field...

You just wait till fails and possibly fry customers $$$$ investment....

That's not customer service...
That's company policy.
And screems: DO NOT USE!!

I used to have the 250A dumb Daly.
And after little over 3 months it just stopped working.

Mulitmeter test, P- to B- "trick", just dead.
It costs $75 to return, and got $150 back via PayPal.
After costs of PayPal and "mandatory conversion" to Euro there was +/- $125 left.
$100,- go "poef" in 3 months.

I'm not American, I don't have the top dollar to spear.
If I pay $150,- I'm expecting something that works longer then 3 months, and I can't bare those experiences of doing this trick every 3 months.

Then the Orion Jr is quickly a cheaper option then Daly....

I'm not sure if any of Daly's people are reading this.. :

One should give free replacement if you know your device is faulty.
For $$ on parts, it's peanuts, so are the postage costs from China as it counts as "third world" for postage
.
You only need to replace the main unit that can be transported in carton bubble envelope as it's supposed to be strong.
Spaghetti wires not needed, unless they are faulty.

Ford remembers really good what the price can be to not update a known defect. (Car brakes)

Samsung does, who have recalled 100.000 or more S7..

List goes on and in and on.
Good companies who care about their customers and functional products.

What is Daly??

Right now harvesting their good name, making top profit while their customers batteries suffering.
For the Lithium polymer.. even set fire.
LiFePO4... Just a few bloated if you are lucky
 
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I haven't tried this but... Why not buy a 16S, 20A Dumb Daly (< $20) and use it to control the coil of a 500A contactor that has a 48v coil. For instance a KiloVac EV200 (NO) with 32-95V DC coil. Draws only 0.03A @ 48V to hold it closed. (I assume there are cheap knock offs available.) BMS only carries coil load. Not programable, but should prevent disaster. You could add your favorite active balancer in parallel. Each component does only One thing, very simply.
I'm sure you don't really understand how daly BMS works, or otherwise you would not have posted this.

Sure, any BMS can be modified to trigger a contractor at high or low voltage.

If you don't care to go dark (no power) when one cell reach 3.65 and you manually need to discharge that cell.... sure.

The Daly (and most other) BMS will stop the charge, but not the discharge (or Visa versa)

Otherwise, not a bad way of thinking to use for BMS.

For continuous used systems, it's a dead stop if the top / low is reached, no longer being continuous.

For charging an E-bike or so, or battery to take on camping trips, sure!
It's not that important that a trigger is a dead stop.

Alternative is Chargery who does the contactors (like DIYBMS) and have 2..
One for charge and one for discharge..

Daly used this way can only trigger one.

Unless you open up the BMS, and tap into the mosfets..
But that is getting close of building your own :)
 
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