Lemme guess. This is a huge pack with many parallel cells and also it’s new?
My pack is just an old 3p 30q. The difference in the internal resistance of the cells has a wayyy bigger impact of the overall balance of the pack.
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Yeah this is a brand new 18s12p 21700 pack
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I should have said more…
It will try to unbalance the pack but the BMS will attempt, via your 0.005V unbalance delta threshold setting, to bring the voltages be back into line.
But if the BMS is discharging cells that would not have been the higher voltage cells at the end of the charge then you’re only extending the charging time by having the low balancing voltage.
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This
If it’s $1 more for nice long silicone-insulated balance wires, everyone will thank you.
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plus $20 worth of labor
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The idea is to avoid the labor of switching them out later when you build the battery.
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I acomplish this by protecting my shitty leads with fishpaper.
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But Y tho
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Thats a real good question…maybe I stop
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mine start at 1.2v 
Do you always charge to within 0.01V of cell max?
I thought it was good practice to stop at ~4.1V at the highest, to extend the pack lifespan.
Some more pictures, showing the thickness
![image|666x500] (upload://u5ZGwZ6igGXTQaIyvTiLeTIF5aW.jpeg)
will run some test(charging a imbalanced pack with high current)
and we will do a trial production
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This connector is surprisingly robust and anti-vibration, it takes about 15 kg of pull force to get it off, and they have metal clips on the side and 2 plastic notch on the top to click itself in place, to my experience, this takes way more effort to get off than the dalybms ph2.0 port which has no clips to hold itself in place.
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Excellent! Thank you for the photos.
I am looking forward to hearing the results of any temperature testing you might do. With the main MOSFETs and the balancing resistors creating heat during charging things can get pretty warm inside an esk8 enclosure.
Just the two MOSFETs on their own will create about 4.5W of heat at 15A. The balancing resistors will add about 0.18W of heat each and all that can add up to a big temperature rise for a board as small as yours, especially with so little copper being available to spread the heat.
Small boards are fantastic but heat is always a challenge. 
Will your aluminum shield be used as a head spreader?
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Nice one! Do I spot a BQ76952 in the wild 
? And will it be open source 
?
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If you have then it won’t work as connected. 
Chip markings are wrong though.
Wow this is looking sweet! Its so small!
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Thats what she said
I’m curious would there be a way to implement a temp sensor?
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Was just a guess, but if you say its not then I believe you 
.
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I believe that is a thermistor (temp sensor) that is connected to those two black wires seen in the photos.
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