16S LiFe BMS Research

methods

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48V-or-60V-Lifepo4-Smart-BMS.jpg

Just stumbled onto this site based on a Google Search of "16S BMS". I recognize that format from earlier research.

16S-60V-or-20S-72V-Bluetooth-BMS.jpg

I am liking what I am seeing so far. Coming from this page
https://www.lithiumbatterypcb.com/product-category/48v-or-60v-battery-bms/

LOL
You can literally see the TVS diodes that DALY did not populate on the version they sent me. Crooks! Saved a dollar, cost me $420. This BMS seems to understand the importance of TVS Diode Protection. M A Y B E their engineer spends more time addressing failure than blaming customers.

C O U G H

* Copper Bus Bars
* Larger number of smaller count connectors (F A R better than 1pcs 17S)
* Heatspreader with multiple temperature probes
* UART tap for datalog, control, networking

You know you dont have to just plug a BLE into that UART, L O L. Super Easy to make a comms bus.

48V-60V-li-ion-or-Lifepo4-Battery-smart-BMS-750x750.jpg

-methods
 
Ok
So this one is looking good to me. I am going to waste some of my time researching it.

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That should say either 48V or 60V, but I can see how the mistake could be made.

* 20A for $47
* 30A for $49
* 50A for $55

Ok, so you would have to have mental problems to select either of the first two options. That is REALLY where I went wrong with DALY, I should have taken one of their 60A units. I only downsized in an attempt to have the BMS limits count toward my cabling protection. If you run a 60A BMS with 10AWG then you definitely have to add breakers or fuses

Which... I do not care for

Anyway
I really like that this PARTICULAR unit STARTS at 16S and goes up! That means its PCBA's are populated with higher voltage components. The last thing you want is to select the one that STOPS at 16S

C O U G H

-methods
 
First one I looked at was here
https://www.lithiumbatterypcb.com/product/16s-17s-18s-19s-20s-lithium-or-lifepo4-smart-bluetooth-battery-bms-with-50a-constant-current/

Now moving on to here (moving right to left across main page)
https://www.lithiumbatterypcb.com/product/48v-60v-72v-li-ion-or-lifepo4-smart-bluetooth-bms-with-30a-40a-50a-constant-current-software-pcb-board-with-uart-and-rs485/

This one has lots of options for UART and RS-485. That is a very good sign! The RS-485

$56-$68 for UART + RS-485 across the range of 30A to 60A

Since this goes up to 20S I am 99.9% certain that if you (I) select the 16S LiFe @ 60A that we will have a QUITE reliable BMS. Tons of margin in there, and a reworkable package.

-methods
 
Oh nice, third one from the right only has a 60A option
Out of stock too...

https://www.lithiumbatterypcb.com/product/12s-13s-14s-15s-16s-17s-18s-19s-20s-li-ion-or-lifepo4-battery-smart-bluetooth-bms-with-60a-constant-current/

What the hell is the difference between all these models one asks

-methods
 
Oh what?
I thought there were 4, this is showing pages worth

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yea dude, this is where people are picking them up at. Here or similar. Feels legit to me. Seeing things like "10K NTC" and "microamps"... keywords I seek.

* RS485
* NTC Specifics
* Quiescent Current specifics
* Hard Programmed but programmable

-methods
 
Wow, uh... ok
Those are all different. This is like the super-store of BMS.

HA!
THERE ARE TWO PAGES TOO!!

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Looks like this bottom row is all high current.

-methods
 
$32 for 20A
Built in bluetooth
https://www.lithiumbatterypcb.com/product/little-size-36v-48v-60v-li-ion-or-lifepo4-smart-bluetooth-bms-with-40a-60a-80a-constant-current-for-10s-to-17s-battery/

60A is only $41.20, so ... you can see where the $10 is going

* 10S to 17S
* Says 3.7V chemistry but will work for both
* ....

Parameters-setting-page.jpg

Yea, I have worked with this software before. The thing to know...

* ONLY LOGS TO PHONE
* NO MEMORY INSIDE BMS
* YOU WILL GET NO DATALOG UNLESS ACTIVELY CONNECTED

Which is Jenk, but I understand.

-methods
 
yea, so...
With that interface you can tune in the short circuit response etc. Very powerful interface. Also means that you are going to have to actually program each one! LOL - you can write a script that does it.

Ok...
Where the hell do I start. That was the second row from the bottom, moving up

16S 50A $29
See what I am talking about doooood?
https://www.lithiumbatterypcb.com/product/20s-lithium-ion-battery-bms-for-72v-battery-pack-with-30a-40a-50a-constant-current-suitable-for-electric-scooter-or-bike-battery-system/

I am not at all talking about $125 or $250, I am talking about CHOSING THE RIGHT bms and getting good value. I do not want or need any of that programmable shit. I just need it to non-suck and pass short circuit test.

-methods
 
I dont know man...

* 1000+ in stock (other stock values were live)
* 50A
* temp probe
* Fixed 16S LiFe, no program
* heat spreader
* Black bottom
* Speak of TVS specifically
* Voltage Margin
* Dude...

84V-Lithium-Battery-PCB-board-1-1.jpg

I am about to just start spending money and see what happens. It would be a dream if a supplier like this had all these options on Amazon Prime. Pay a little more, get it tomorrow, less hassle.

-methods
 

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At some point you have to STOP RESEARCHING and START BUYING - lol

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There could be 20 BMS that are better on that website, but do I have time for that crap? NAH BRUH, $200/hr is what it costs for me to research.

SO HOW DO WE LOWER RISK

Risk of incorrect configuration
* Programmable units offer you chance to correct this

Risk of take 1000 years to ship
* Meh, always pay for express, it will arrive
* Better yet, buy Amazon Prime, get it tomorrow

Risk of send garbage not like pictures
* Death is what they seek then

Eh... Programmable vs Unprogrammable
* Costs more
* Draws more current
* Lame when you are building lots of packs
* Gives idiots chance to apply poor settings!!!

But...
* Allows you to tune in when performance is bad
* Set overcurrent to act faster, be more sensitive, protect chinese mosfets

NOW
POTTED VS UNPOTTED
* Hands Down you want UNPOTTED
* You can update or modify these
* You cant get your BMS wet anyway!

Dude, any DALY dream of going wet is a total joke. They did not even pack the 17S connector with grease. It would self destruct in no time. And - bruh - if your BMS is getting wet then your battery is done anyway. This is what happens to wet pouch cells.

[youtube]75bX7hVkVAg[/youtube]

No joke bro
You keep your batteries dry. ZERO points for a "waterproof" bms. The only reason you would want potting is for HEAT SPREADING, and in that case, you have to use good, thermally conductive, goopers

Nop
This STYLE of bms is what I am going with. All those expensive units on Amazon, zero doubt this is where they are getting them. Here or similar, in 100pcs at a time. GOOD OL PRICE if you take 50-100pcs dude. You have no idea.

-methods
 
Express Shipping stays flat as you increase number of units in cart!
That is good sign

eh... I could pull the trigger now, but this actually needs another 4hrs of research to understand the tradeoffs of all the various flavors. +/- $10 could mean a really big difference. Best Value is hiding in here somewhere...

... and
I am going to try and Image Search this vendor out to an Amazon Prime offering to try and hit the highest volume. My REAL GOAL is to buy something that is in HIGH VOLUME and not some one-off shit.

Dude
* High Volume drives down cost
* High Volume drives up reliability
* High Volume drives down delivery time
* High Volume...

Did I tell you that I now focus on ISO 9001 setups, Pilot Production, Manufacturing of Electronics, etc? I literally write QMS and MES systems from scratch, set up manufacturing lines from empty building, etc.

methods is on the way down

-methods
 
Ok
now... after a "Depth & Breadth Charge" like that, NOW I look at

* Who are these guys
* Where are they
* Who do they cater too
* How long have they been around
* Do they practice ISO 9001
* Do they maintain Quality
* Do they do custom requests

Right?
Like how about methods orders the smallest one but sends you 500pcs mosfet to populate. Eh?

Like that
Populate things with my own gear. Get a consistent outcome. Buy 200pcs, sell them to break even, get mine

* At Cost
* Free
* At Profit

Right?
This is like... $10k gamble range. I have been playing with $100k gamble and that NO FUN. Lol... $10K gamble I can make. Maybe I break the market eh?

* Populate with good US mosfets
* Clearly mark that mine are different
* Show how to tell mine are different
* SELL AT COST


MOOO HOOO HAAA HAA HAAA

All the guys who are marking up
* 100%
* 200%
* 300%

These guys... they hate me. That is fine. They are not truest friends of the revolution if they take that much profit for doing nothing but ordering shit from china and slapping a sticker on it. AT BEST... what they are offering is value-add in the form of customer support, some de-risking, some filtering...

yea

In the famous words: "Hey Guys, Watch This" - LOL

-methods
 
Requirements
Dictated from the toilet

* Must be generic

This is going to drive a requirement for it to be programmable. Whatever we pick has to work for 3.7 and 3.3 volt chemistries.

That rules out a ton of options... But it's the right choice. When you talk on the pull-down menu all you are doing is asking them to program it for you so it arrives turnkey.

Yep

So...

* Must handle 60A

That should put it in a class to support all e-bikes with 300% margin. Most e-bikes draw like 20 amps. A 60 amp BMS should be plenty. Yeah I will be huge, but I have no requirement to make my BMS small

It would be more universally applicable if it were small. Being small also drives up the quality of the mosfets. HAS TO... SO IT'S SOMETHING TO THINK ABOUT.

A larger number of lower quality mosfets is not as reliable as a smaller number of higher quality mosfets. This is fact.

-methods
 
* programmable
* 50A or more
* Margin over 16S life

....

Still dictating from the toilet. The thunder mug. The porcelain throne. The porcelain god Ralph.

My home away from home

....

* Must have external temperature probe or probes
* Must survive short circuit testing

Carefully note that the more legitimate BMS will call out what type of short circuit test!

* Short into load

That means it's not a true Short Circuit!!!!! They're saying that you can't dump like 200 amps into a blown circuit. They are not saying you can just hook the wires together

Cough

* Must be common port
* Must be under $42

I might have to buy 20 pieces to get my cost down. If shipping is flat then buying one actually cost you double! You have to think about this.

* $30 shipping
* $3 each for 10pcs

Right?
This is toilet logic

-methods
 
Ok, then you scroll up and compile the requirements

* Programmable supporting 3.3, 3.6, 3.7V chemistries
* 50A or better current handling
* Voltage margin over 16S LiFePO4
* External temperature probe or probes
* Shipping that saves with scale
* Survives Short Circuit Testing
* A Chance at High Volume / Wide Use
* No rules on what I can sell it for (at cost + shipping + shipping)
* Preference on smaller, but will accept H U G E
* Preference on ISO 9001 or similar Quality Standards
* Must be Common Port
* Must have Express Shipping, I slow boat N O T H I N G
* Preference for supplier that will create something custom for me
* MUST be "Friend of Revolution"
* Preference for calling out TVS, but have TVS protecting mosfets
* Preference for exposed board that I can repair or modify
* Must come with all cabling, cabling must be of acceptable quality
* Strongly prefer that it does not run if a balance tap breaks (Fail OPEN)
* Strongly prefer that it self limit if overheat
* Must balance, more is better, programmable is better
* Must have cell level LVC, HVC, actual control over current (duh)
* Must have reasonable self discharge rate (quiescent current)
* Must have consistent quality!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
* Must be IN STOCK, with stock quantities shown live
* Strongly Prefer Amazon Prime (and I will pay for it)

Like that yo

Incomplete but complete enough to pair down. Run that list and there should be only 3 or 5 left and the deal will be obvious.

-methods
 
Three down for not being programmable

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7 more down for too high of current

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16 per page
8 per image above
Moving to second page of "16S BMS"

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All the second page eliminated for
* No BMS, Too high current, etc

SO...

That is called "Down Selecting", the first pass.

-methods
 
Next what I do is LITERALLY open all of the tabs and start digging trying to eliminate for

* Mislabel
* Not in stock
* too high price

Etc. I suspect we will not be able to hit our $42 target (even without shipping) so we wont sort by that.

* RELIABILITY
* SAFETY
* QUALITY
* VALUE

In that order! YOU CAN NOT ... NOT... NOT... sort by price first. If you do then you are an idiot. I have already blown hundreds just doing this research for you.

cough

Electrical Engineer with 20 years relevant experience. Tell me whatever you want, I really don't care.

-methods
 
I end up with 6 to pick thru.
6 is easier than 20+ right?

* Progress

Coins.png

Now to go cook breakfast

-methods
 
LLT Power eh?
Even if we do not go with them, they are SURE LOOKING LIKE FotR

* Friend
* of
* the
* Revolution

Support your friends.

-methods
 
Here are all the links to sort thru

Source
https://www.lithiumbatterypcb.com/product-category/48v-or-60v-battery-bms/

Down Selections on first phase
https://www.lithiumbatterypcb.com/product/10s-12s-13s-14s-15s-16s-17s-li-ion-or-lifepo4-smart-bluetooth-bms-with-40a-60a-80a-constant-current-for-36v-48v-60v-battery-pack/
https://www.lithiumbatterypcb.com/product/12s-13s-14s-15s-16s-17s-18s-19s-20s-li-ion-or-lifepo4-battery-smart-bluetooth-bms-with-60a-constant-current/
https://www.lithiumbatterypcb.com/product/48v-60v-72v-li-ion-or-lifepo4-smart-bluetooth-bms-with-30a-40a-50a-constant-current-software-pcb-board-with-uart-and-rs485/
https://www.lithiumbatterypcb.com/product/16s-17s-18s-19s-20s-lithium-or-lifepo4-smart-bluetooth-battery-bms-with-50a-constant-current/
https://www.lithiumbatterypcb.com/product/16s-20s-17s-18s-li-ion-or-lifepo4-smart-bms-with-20a-to-40a-constant-discharge-current-bluetooth-function/
https://www.lithiumbatterypcb.com/product/little-size-36v-48v-60v-li-ion-or-lifepo4-smart-bluetooth-bms-with-40a-60a-80a-constant-current-for-10s-to-17s-battery/

This is actual work bro. Nobody is doing this for you for free - L O L. Disciplined Work. Not gamble. Not play time. Work.

-methods
 
Going to the first link on the toilet again

* Isolated UART

THAT IS A VERY VERY GOOD SIGN

This BMS is understood to integrate with next assembly. You absolutely cannot just link them together with a standard uart and common ground.

* Yeah it might work on your bench
* No it won't work in the field

Look at all those goodies...... This was specified by a customer. Guaranteed.

Screenshot_20221126-074622_compress77.jpg

Notice that I am still compressing all of my files including screenshots. Ass Piss is what we call it in the industry.

-methods
 
Some really good specifications in here

* 300uS response to short
* <10mOhm ON resistance
* 200uA sleep

Screenshot_20221126-075343_compress44.jpg

I'd like to know what that relay-on current draw of 20 milliamp is...

... So you just go through them looking for non starters

-methods
 
What does "Over current protection current 7~13 times" mean?
Maybe it blows up after you hit over current 7 times.
 
Ok
I woke up at 0330 and got out of bed at exactly 0420 (body clock is ON!). I have to go slog the garage so lets see if we can eliminate any of these 6 or ideally all but 1

GO

-methods
 
fechter said:
What does "Over current protection current 7~13 times" mean?
Maybe it blows up after you hit over current 7 times.

Super LOL
I know you are joking but they are just saying that it will cut out at 7-13 times the rated current. This is the HARDWARE cutout, and they specifically call out

* Hardware Limits
* Software Limits

The chemistry specific settings are of course all software, but the current limit is and should be HARDWARE + Software. ... So, basically the gains on the OpAmps.

But hey bub... You claiming that you already know this supplier sucks? If so, save me some time bruh! :kff:

-methods
 
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