bluetooth BMS?

ElectricGod said:

mpmoller said:

flippy said:

charging current and voltages need to be handled by the charger, not the bms. the bms is a PROTECTION device, it only does its job when shit goes OUT of spec.

if you got too much charging current you need to limit it at the charger side, not the battery side. or do you use the brake to keep the speed instead of lifting off the trottle?

Click to expand...

Well thank you flippy... I guess.
Can you suggest me a charger that can charge a 72v (max 84v) 18ah battery?

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I use meanwell PSU's for my chargers. Here's my thread on building chargers.
https://endless-sphere.com/forums/viewtopic.php?f=14&t=90292&p=1316096#p1316096

Click to expand...

I dont feel like i got the knowhow to make one of these conversions. But thanks anyways!

Hey everyone,

I was looking at the 20S smart BMS to buy a few more of them and there's a link on them now for this LCD.



https://www.aliexpress.com/store/product/20S-Lipo-LiFePO4-Lithium-Battery-Protection-Board-60V-72V-Li-ion-Cell-Smart-Phone-APP-PC/2856009_32863752220.html?spm=2114.12010612.8148356.29.6d683de2Y6sosn

In the description is says this:

if you need LCD display , click this link :

http://www.aliexpress.com/item/Smart-Intelligent-Lithium-Battery-Protection-Board-LCD-Screen-Display-Single-Cell-voltage-Capacity-Temperature-Information-Show/32878566013.html

And then you get to an interesting LCD that has 4 buttons that supposedly can program the BMS and also acts as a dashboard.

https://www.aliexpress.com/item/Smart-Intelligent-Lithium-Battery-Protection-Board-LCD-Screen-Display-Single-Cell-voltage-Capacity-Temperature-Information-Show/32878566013.html?spm=2114.12010108.1000023.10.4d8d13d0XaQ4sl

These BMS only have a single UART so you choose what it connects to. USB, BT or LCD, but not 2 or more at the same time.

mpmoller said:

I dont feel like i got the knowhow to make one of these conversions. But thanks anyways!

Click to expand...

Check the meanwell number on your local supplier, that only requires you to connect one postive to the negative of the second one and setting the voltagr to 42V om each charger to get to 84. You can turn the current pot to the maximum if you have enough air cooling around the unit.

flippy said:

mpmoller said:

I dont feel like i got the knowhow to make one of these conversions. But thanks anyways!

Click to expand...

Check the meanwell number on your local supplier, that only requires you to connect one postive to the negative of the second one and setting the voltagr to 42V om each charger to get to 84. You can turn the current pot to the maximum if you have enough air cooling around the unit.

Click to expand...

MPMOLLER...
Making a charger is not rocket science. I use the Meanwell SE-600 series PSU's. They are pretty bullet proof.

If people are in the USA and want something from IC GOGOGO such as a smart BMS, I'm about to order a few items myself. You can PM me and I'll add you to my order. WE can talk about money in the PM.

This is their main page on aliexpress:
https://www.aliexpress.com/store/2856009?spm=2114.search0104.3.284.1bdc40feB4hXZS

Items discussed in this thread:

32S smart BMS with LCD and BT: (LIPO, LION, LIFE, LTO)
https://www.aliexpress.com/store/product/Smart-Display-16-32S-Cells-300A-200A-150A-100A-70A-Lithium-Battery-Protection-Board-Balance-BMS/2856009_32826469363.html?spm=2114.12010612.8148356.2.7d9b3de2Pn5Msg


24S smart BMS with LCD and BT: (LIPO, LION, LIFE, LTO)
https://www.aliexpress.com/store/product/Smart-Display-300A-8-24S-Cells-Lithium-Battery-Protection-Board-Balance-BMS-Coulomb-Meter-Lithium-iron/2856009_32827394534.html?spm=2114.12010612.8148356.4.7d9b3de2Pn5Msg

20S smart BMS with BT: (LIPO, LION and LIFE)
https://www.aliexpress.com/store/product/20S-Lipo-LiFePO4-Lithium-Battery-Protection-Board-60V-72V-Li-ion-Cell-Smart-Phone-APP-PC/2856009_32863752220.html?spm=2114.12010612.8148356.34.7d9b3de2Pn5Msg

16S smart BMS with BT: (LIPO, LION and LIFE)
https://www.aliexpress.com/store/product/16S-Lipo-LiFePO4-Lithium-Battery-Protection-Board-60V-48V-Li-ion-Cell-Smart-Phone-APP-Computer/2856009_32872975737.html?spm=2114.12010612.8148356.18.7d9b3de2Pn5Msg

7S to 112S BMS/balancer with LCD: (LIPO, LION, LIFE, LTO)
https://www.aliexpress.com/store/product/112S-35S-Lithium-Li-ion-LiFePO4-LTO-Lipo-Battery-Protection-Board-BMS-Balance-Bluetooth-APP-7S/2856009_32861093603.html?spm=2114.12010612.8148356.42.7d9b3de2Pn5Msg

does anyone know how to get the UART sn30183 to work on a windows 10 PC ?

it installed software and logs in ok.

also put the usb cable and it installed some drivers ? but then when I run the JBDtools apps.

the comm port has nothing when I refresh and the blue light never flashes inside just solid blue ? anyone have any luck

by the way the Phone app works perfect when I plug in the wirless connection

Also how long should it take to balance ?

so it does 50ma balance current but it pulses this every 5 seconds.

I have a 10ah 36v battery I am trying to balance, left it over night and it barely changed ?

the difference is only around 200millivolts ? i.e max cell was 3.998 and the weakest was 3.789v

how can I tell the balancing is working ? I can see it flashes B, but I can barely notice after hours that the voltage is dropping ? I man the voltage drops when I take it off the charger fast ! but its the BMs does not drain it down much or fast ?

ElectricGod said:

7S to 112S BMS/balancer with LCD: (LIPO, LION, LIFE, LTO)
https://www.aliexpress.com/store/product/112S-35S-Lithium-Li-ion-LiFePO4-LTO-Lipo-Battery-Protection-Board-BMS-Balance-Bluetooth-APP-7S/2856009_32861093603.html?spm=2114.12010612.8148356.42.7d9b3de2Pn5Msg

Click to expand...

Did you happen to look at the unpopulated 4 pin header next to the LCD plug on these ones? I see two lines running to the stm chip so perhaps it's another serial port?

Alex07 said:

Also how long should it take to balance ?

so it does 50ma balance current but it pulses this every 5 seconds.

I have a 10ah 36v battery I am trying to balance, left it over night and it barely changed ?

the difference is only around 200millivolts ? i.e max cell was 3.998 and the weakest was 3.789v

how can I tell the balancing is working ? I can see it flashes B, but I can barely notice after hours that the voltage is dropping ? I man the voltage drops when I take it off the charger fast ! but its the BMs does not drain it down much or fast ?

Click to expand...

A bms balance feature is to KEEP it balanced, not make it balanced. You should do that with a external balance charger.

Charge it up to 4.1V per cell. That increases the current during balancing and also makes the differencs between cells more pronounced.

flippy said:

Alex07 said:

Also how long should it take to balance ?

so it does 50ma balance current but it pulses this every 5 seconds.

I have a 10ah 36v battery I am trying to balance, left it over night and it barely changed ?

the difference is only around 200millivolts ? i.e max cell was 3.998 and the weakest was 3.789v

how can I tell the balancing is working ? I can see it flashes B, but I can barely notice after hours that the voltage is dropping ? I man the voltage drops when I take it off the charger fast ! but its the BMs does not drain it down much or fast ?

Click to expand...

A bms balance feature is to KEEP it balanced, not make it balanced. You should do that with a external balance charger.

Charge it up to 4.1V per cell. That increases the current during balancing and also makes the differencs between cells more pronounced.

Click to expand...

And 200mV isn't exactly small. That can be 15-25% of your useable cell capacity.

One option is to charge the low cells individually. There are a number of inexpensive hobby chargers that you can set your charge rate and termination voltage as you need. Just never use more than one of these chargers at a time on a pack as generally the DC and AC grounds of the input and output are not isolated and you will blow up chargers and possibly batteries if you miss a common ground.

Having said that though you can end up in worse shape if the low cell you are trying to "catch up" is actually a weak cell. But if that is the case the cell needs to be replaced anyway so it's not really worse, just helps diagnose a bad cell.

If you can afford one there are a number of hobby chargers on the market that will do 10s, I'm assuming 10 by your voltage, that will give you charge and discharge curves if you use their PC software. It's a good way to get in balance and diagnose a pack for bad cells.

Alex07 said:

Also how long should it take to balance ?

so it does 50ma balance current but it pulses this every 5 seconds.

I have a 10ah 36v battery I am trying to balance, left it over night and it barely changed ?

the difference is only around 200millivolts ? i.e max cell was 3.998 and the weakest was 3.789v

how can I tell the balancing is working ? I can see it flashes B, but I can barely notice after hours that the voltage is dropping ? I man the voltage drops when I take it off the charger fast ! but its the BMs does not drain it down much or fast ?

Click to expand...

I'm not sure what BMS you are using so you might want to tell this information first.
In my case it took around 15 minutes, but my cells were pretty much balanced to begin with.

You can set the target difference in the bluetooth app, in my case I set up to 0.002V. In the end all the cells were within this range.
Balancing is working this way:
-1st: you fully charge your battery
-2nd: disconnect the charger
-3rd: use the bluetooth app to enable balancing

The BMS will look at all the cells voltages and drain the cells that are higher until they all reach the same level as the less charged one.
Once they are all within the difference you set, then the balancing action will stop and you'll be good to go.

But again, that might depend on what BMS you're using.

I have the xioxing bluetooth BMS from this thread not the one with the lcd.

I am using the bluetooh APP.

unfortunately I do not have a balance charger, I have left it 24 hours and done another charge cycle.. so it seems to be balancing as now the gap from the highest to lowest cell has closed from :
the difference is only around 200millivolts ? i.e max cell was 3.998 and the weakest was 3.789v

to 4.144 to 4v i.e 144millivolts in 24 hours. so 56 Millitvolts a day , so it should be finished in 4 days lol ?

I still cannot get the desktop app to work as it doesn't pick up my comm port ?

for balance start voltage I have 4v and max voltage per cell set to 4.18v for my lg2.85mah 18650's does that sound ok ? this is an old pack.... so hopeing it can do its job from 4v.. otherwise I could start balance at 3.5v ?

Run your pack down a little.

What's your balance turn-on voltage? To get balancing started earlier set this value lower. Which balance mode are you using?



Com port issue...when you plug in the USB box into your computer do you hear the up tone sequence that indicates that windows detected the hardware getting plugged in? Have you checked in device manager for the com port? Whatever device manager says it is, that's what you enter in the app.

This BMS is just the big brother to the smaller BMS that we have seen so much of in this thread. And when I say big brother, I really mean it! This thing is BIG, but it's also capable of 20-30S and from the factory good for 80 amps. However, everything about it says that 80 amps is just for starters. Replace all those pathetic HY3712 mosfets with much better 150 volt mosfets (AOT2500) and populate all P- 20 positions and there's no reason to believe that 300 - 400 amps is not possible. Otherwise, decent copper busses, lots of places for shunts and lots of places for mosfets. While quite large, this BMS has lots of current handling capability.

The existing mosfets are HY3712's...which are downright horrible mosfets. The original part number is 2SK3712, but this is the Chinese version so we all know that means is sooooo much better. OK no...NOT really. They are 250 volts, 9 amp, 40 watt, 450 milliohm mosfets. Can you say worthless garbage?! Geez...these things are so NOT anything slightly worthwhile it's ridiculous! No wonder with 14 mosfets the BMS is good for 80 amps. I'll obviously be pulling every single one of them out of the P- side and replacing them with AOT2500's. What a garbage mosfet!

The 16/20S version is about 2/5th's the size of this BMS. The 20-30S BMS is a good bit thicker since there's mosfets on both sides of the board.



Like the smaller 16/20S BMS, unsolder a few connections and change the setting in the PC app and this BMS supports 30S. I'll need to add a few wires to the balance cable, but that's super easy.




Does anybody know what you call this rubbery heat sink tape stuff? I'd like to order a roll of it if I knew what it was called.



Replacing those .5w shunts with 2 watt shunts will be easy. There's 10 mosfets per side of the board for both P- and C-. 20 mosfets for decent ones is LOTS of current!



Board top and bottom.

ElectricGod said:

Does anybody know what you call this rubbery heat sink tape stuff? I'd like to order a roll of it if I knew what it was called

Click to expand...

"Silicone thermal pad" will lead you to it

themelon said:

ElectricGod said:

Does anybody know what you call this rubbery heat sink tape stuff? I'd like to order a roll of it if I knew what it was called

Click to expand...

"Silicone thermal pad" will lead you to it

Click to expand...

I found it...thermal gap filler.

https://www.ebay.com/itm/100-100-1-5mm-Thermal-Pad-the-high-Performance-Gap-Filler-GPU-CPU-Heatsink/192129057842?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

thermal conductive pad usually gets the good stuff. sillicone is not good for heat transfer.

This is what 46 7S boards looks like...arrived today.

flippy said:

thermal conductive pad usually gets the good stuff. sillicone is not good for heat transfer.

Click to expand...

True, as i use sillicone hot pads to pull stuff from the oven. I don't think any of the stuff I have ever bought that was labeled as such actually had sillicone in it as it has always worked just fine. Not sure why it didn't occur to me when I wrote that as now it seems like a dumb statement.

ElectricGod said:

This BMS is just the big brother to the smaller BMS that we have seen so much of in this thread. And when I say big brother, I really mean it! This thing is BIG, but it's also capable of 20-30S and from the factory good for 80 amps. However, everything about it says that 80 amps is just for starters. Replace all those pathetic HY3712 mosfets with much better 150 volt mosfets (AOT2500) and populate all P- 20 positions and there's no reason to believe that 300 - 400 amps is not possible. Otherwise, decent copper busses, lots of places for shunts and lots of places for mosfets. While quite large, this BMS has lots of current handling capability.

Click to expand...

Got a link for this one? I could not spot it on the crappy mobile site...

themelon said:

ElectricGod said:

This BMS is just the big brother to the smaller BMS that we have seen so much of in this thread. And when I say big brother, I really mean it! This thing is BIG, but it's also capable of 20-30S and from the factory good for 80 amps. However, everything about it says that 80 amps is just for starters. Replace all those pathetic HY3712 mosfets with much better 150 volt mosfets (AOT2500) and populate all P- 20 positions and there's no reason to believe that 300 - 400 amps is not possible. Otherwise, decent copper busses, lots of places for shunts and lots of places for mosfets. While quite large, this BMS has lots of current handling capability.

Click to expand...

Got a link for this one? I could not spot it on the crappy mobile site...

Click to expand...

This is the 24S version, but there's no difference except a couple of balance wires and some solder bridges.

https://www.aliexpress.com/store/product/30S-lifepo4-Lipo-Lithium-Battery-Protection-Board-Li-ion-Smart-BMS-Phone-APP-Computer-Communication-40A/2856009_32871176438.html?spm=2114.12010612.8148356.52.6f863de21IEi1Y

The page now lists and LCD for it too. It has lots of Chinese on the display...don;t know how useful that is.

if you need LCD display , click this link :

http://www.aliexpress.com/item/Smart-Intelligent-Lithium-Battery-Protection-Board-LCD-Screen-Display-Single-Cell-voltage-Capacity-Temperature-Information-Show/32878566013.html

ElectricGod said:

This is what 46 7S boards looks like...arrived today.

Click to expand...

I could use 4 boxes like that...

themelon said:

ElectricGod said:

This is what 46 7S boards looks like...arrived today.

Click to expand...

I could use 4 boxes like that...

Click to expand...

These BMS are quite small. 4 boxes would be like 2000 of them.

I upgraded a 20S BMS for a pal in the UK with 2 watt shunts, larger copper busses, legit IRF4110's from digikey in P-, 5.5mm bullets for B- and P- and a 14 awg wire at C- for charging. I also made the balance cable adapt to 4S packs. This is on a 32S pack, but I'm only using the first 20 cells. I put taps on it at 20S, 24S, 28S and 32S. Whatever size BMS I want to use on it is possible.

ElectricGod said:

themelon said:

ElectricGod said:

This is what 46 7S boards looks like...arrived today.

Click to expand...

I could use 4 boxes like that...

Click to expand...

These BMS are quite small. 4 boxes would be like 2000 of them.

Click to expand...

Not full boxes, just the quantity contained within it. I should have been more specific. I have 84 12s and 24 6s Volt modules that I may want to put these on. That's 216 boards if I don't do any additional paralleling with them.