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I just picked one up from Amazon for $429, first one that does everything I want, 60A charge to house, reverse 30 amp charge to starter, bluetooth app that can adjust charge current and and all house battery parameters and lithium support ,looks like it even does lithium activation to wake...

A lot of people having issues with large inverters are because they are physically disconnecting and reconnecting the inverter on a regular basis which causes a large inrush on the inverter caps. Also there are reports the new Bluetooth BMS is more sensitive to overcurrent than the old one. So...

Nice addition to show the the protection mode, should help with troubleshooting. Would be a huge downgrade to only have 120 amps peak discharge, not only does my older one do above 140 continuous it will surge up to 200 for 3 seconds and 330 amps for a few ms. Then you look at Battleborn who...

Battleborn makes a good product and all, but you would be in the same boat since they don't even offer a bluetooth version as of yet. I do imagine if they ever come out with one and app it will be more polished and better supported, if... I do wonder if BB has the shutdown issues with inverter...

The new lower overcurrent threshold on the bluetooth version of the BMS is being discussed here: https://diysolarforum.com/threads/new-sok-bluetooth-bms-for-diy.33945/ There are reports its 50 amps or 0.25C, not 25 amps like your are reporting, even 50 amps is much lower than it should be for a...

I am very surprised they shutdown above 50 amps charging, being a single port BMS it should have no issue handling same charge as discharge which should be 120 amps. 50 amps is only 0.25C and would be a pretty ridiculous cutoff for the 206ah, for sure my non blue tooth 206 can handle 110amps...

Just use some electric heaters on an inverter :), can switch the heaters high and low to give some control. I did close to 300 amps using my Coleman AC and microwave at the same time. With a large inverter large loads are easy to come by, could also do hybrid load sharing to adjust current draw...

Seems like more people are reporting issues with inverter cap charge and generator starting with the new Bluetooth BMS, so it seems like the surge ratings are lower. Was hoping the Bluetooth would be the other way around since the published continuous is higher. Really need more definitive...

You can also do a pre-charge resistor setup with a switch to limit inrush, would be nice if the inverter had that built in or the BMS could temporarily limit current by PWM'ing the FET's, maybe we will see that in the future as this seems to be common issue with BMS's and large inverters...

Normally to have the discharge FET off with a voltage above LVCO would mean an overcurrent event. Usually this is because something with a large capacitance is connected like a large inverter causing a temporary high in rush current. I can't think of a reason why the BMS would disconnect...

Whats the bluetooth app say when asleep? Whats the internal voltage and is the discharge FET turned off? Would be odd behavior to sleep like just because of no load unless some internal parasitic load drains the batteries to LVCO. Also inverter cap inrush can do this if your physically...

Ok the IC is specific for BMS's (I need to learn to read Chinese) and has a charge sense pin rated at 40v most and probably internal divider to ADC, technically you could put a another divider in front of it and change the software to read the new lower value properly, its not like the charge...

Isn't the ADC going to have a voltage divider anyway? Doubling the voltage division would allow it handle 80v instead of 40v.

Just for perspective, an entire bluetooth SOK BMS is $100 retail which is one reason why nice contactors are normally not used due to the additional cost it would add to the battery (along with power draw). If I was doing a high voltage solar installation or definitely a large DIY battery then...

Excellent work here tracking down root cause and showing us and even better getting SOK to improve the design, thank you. Does seem like they could design the IC such that it is driven off the battery side so that once the FET's are shutdown due to over voltage the IC would never be in the...

They are also not cheap and they would normally consume power unless bistable (even more expensive) this all adds cost and complexity and potentially battery drain. You can keep adding various switches in series to keep increasing the over voltage protection its not rocket science but there are...

This is what I am disproving, it is false, YES YOU CAN PARALLEL THEM. There is no difference between two batteries of equal capacity in parallel or of different capacities other than the proportion of current. 1C has no more to do with it than it does with batteries of equal capacity. The cells...

Anybody have a theory why an 85v rated FET failed at 50v? Cheap FET or maybe gate voltage?

Well SOK lists 50 amps max charge 100 amps max discharge however I know the overcurrent limits on my 206's are above 110 amps charge / 140 discharge and Min from SOK gave some info to Cinergi here that the BMS is actually rated fro 150 amp continuous charge/discharge and would only cut off after...

Excellent video, this is the kind of tests I want to see, would love to see an over current one as well :).

Nothing stopping someone from using a BMS with lead acid, I have never seen it, most rely on their solar controller to not accidentally pass high voltage to battery. I am sure there are voltage sensitive relays out there that could be used as a OV protection device for any battery and might...

Not sure what else they could do, FETs tend fail short there is no way to guarantee they fail open, there are two in series so both have to fail however you have many in parallel and any set of two can fail and cause current to pass. Only way to make it safer is to add more switches in series...

I think Will has the funds to do it and the video would easily recoup the costs, he's destroyed much more than 5k in teardowns. Over voltage and over current test are sorely needed to get a grip on BMS quality, at this point LFP's all seem limited by the BMS capabilities. This is an uncommon...

Why do these BMS have a 4 series limit? Given enough voltage anything will conduct, its just a matter of how much it can withstand. 17v was after they noticed the problem, once current flows voltage would be pulled down from VOC of 93v. Relion, Battelborn and SOK all list over charge protection...

This is no different than any parallel battery configuration other than the proportions. So long as your load does not exceed the BMS capabilities there is no issue. Just like parallel batteries of equal size split the load and you can size your load according to an equal split, with different...

Are you sure it wasn’t used for large format pouch cells, why do the prismatics get the abbreviation?

Large format prismatic is not used enough to warrant abbreviating it and would be confusing since LFP has been used to denote chemistry in publications for many years.

I can find no references anywhere for someone using LFP to mean large format prismatic however using LFP for lithium iron chemistry seems to go back to at least 2007 when these batteries where first being looked at for EV use in publication such as this one...

Yes disappointing considering they advertised it would have heater function and install pictures show BMS with heater leads. Will be interesting to see how they handle the heater upgrade kit they say will be coming out in a few weeks. I did grab screen shot of video they posted showing password...

So long as your wiring is done correctly and batteries are of similar capacity current will be shared and neither battery will "detect" more than half the current. A 100 amp rated BMS is going to be its continuous rating, it will typically have a much higher surge rating of 2-3x where it can...

Based on my understanding the aging process is primarily temperature driven and lower is better for storage. That is storing a battery at 0F will have less calendar aging than one stored at 77F given the same SOC. Charging below 0F is not good LFP, storing is actually very good even at 100% SOC...

Look closely at the research paper Will linked, SOC seems to show a minor role in the aging process before 20% degradation and actually a protective effect past 20%. 50% and 90% SOC seem to meet at 20% degradation at the same time temperature however plays a major role, generally the lower the...

Looks like its back on the site and someone already received a couple and posted them working in the FB group as a replacement in their 100ah SOK's. They reported the app working at least 30ft away even through the metal case.

Following. My understanding is LFP is a lower voltage chemistry and therefore has very minimal voltage driven aging compared to say NMC. This is why Battleborn says floating at 13.6v is "perfect" as the battery will just sit at 100% without taking any additional charge and that for storage they...

Weird they made a announcement in their FB group and said it would ship in Feb. Here is a screenshot of the App from the iOS app store: