can I program my Li ion 3.7V 4S 100A daly BMS

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I am planning on making a 4s 12-volt 18650 battery pack but was wondering if I could change the depth of charge and depth of discharge to make it more 12-volt friendly. I recently ordered a Li-ion 3.7V 4S 100A Daly BMS https://www.aliexpress.com/item/4000837336363.html?spm=a2g0s.9042311.0.0.3ae84c4dRdzqcO and was wondering if there was an easy way to change the parameters on it. I took a look at these guys https://diysolarforum.com/threads/daly-bms-uart.14777/ and it looked like these https://www.ebay.com/itm/PL2303TA-U...278066?hash=item366137c1f2:g:hC8AAOSwvLFeldVv work well for them but I'm not sure if it's compatible with my BMS, is there any simple way to check?
 

snoobler

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The issue with 3.7V chemistry is it's just garbage for 12V applications. Changing the BMS ranges doesn't change how the cell performs.
 
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I kind of impulse bought the batteries if I did it again I would have gone with Palmer, the reason I'm still doing 12-volt is that all of my equipment is 12-volt and I'm okay with losing some of my capacity.
 
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I was thinking about that but I plan on using at least 100 A, I would prefer to lose the power on the high end, i’m probably going to set my solar charge controller to charge it to a lower voltage
 
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Out of my 3500wh I plan on using 3000wh and living the rest as headroom, I was just wondering if there’s anyway I could add that to my BMS
 
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snoobler

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What peak voltage? Some 12V equipment will get pretty unhappy 15V+. At 3.75V/call peak, you may lose quite a bit.
 
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min of 12.6v nom 14.4v and a max of 15v. here's a drawing I made of the battery I don't know if that will help at all
 

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snoobler

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At 15V max, you'll likely only have about 50% of the capacity available.

Are those nickel strips going to be adequate for 100A?
 
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I was looking at this chart and I was thinking about getting each cell 3.75v x 4s = 15v which should be around 80%. and I was planning on discharging to 3.5v x 4s = 14v. do you think that would work, in theory I should be able to use 70% of the battery. yes, I got the nickel strips from Battery hookup.com 3p and 6p.
In this guy's video each fuse can take 8 amps there are 48 cells total for the busbar 8a x 48 = 384a I only plan on using a 100a. do you think I would just be able to plug my BMS into my pc if I got this https://www.ebay.com/itm/PL2303TA-U...278066?hash=item366137c1f2:g:hC8AAOSwvLFeldVv also is there any certain software I need to program the BMS. thank you very much for the help :) .
 

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I took a closer look at some of my equipment and it turns out most of it can go to 16 volts the only thing that would have an issue is some 12v LED lights and a 12-volt to USB adapter. even my inverter works at 16 volts. also, do you think I'd be able to charge my battery with just one 100-watt solar panel or do you think I should get 200w in series
 

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snoobler

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For the 12V LEDs, that's a perfect application for the converter.

There are the same wide input range 8-40V to 5V USB adapters.


While I see numbers in the sketch above, please disclose the Wh of the pack.
 

12street

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The issue with 3.7V chemistry is it's just garbage for 12V applications. Changing the BMS ranges doesn't change how the cell performs.
I just received a message from DALY stating that it was acceptable to use the BMS I have, which ranges from 2.5v 50 3.7v, nominal 3.2v, on any LiFePO4 battery system.
I am dubious, and do not want to attach it to my Lishen cells without input from this community.
Please advise -I do not see how this is healthy for my cells which I would truly prefer to max charge 3.4-3.5V.
Thank you.
 

snoobler

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I just received a message from DALY stating that it was acceptable to use the BMS I have, which ranges from 2.5v 50 3.7v, nominal 3.2v, on any LiFePO4 battery system.
I am dubious, and do not want to attach it to my Lishen cells without input from this community.
Please advise -I do not see how this is healthy for my cells which I would truly prefer to max charge 3.4-3.5V.
Thank you.

2.5-3.7 is essentially the operating range of LFP. Since they've said 3.2V nominal, that further confirms it's suitable for LFP.
 
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