DIY Lithium Battery Balancer and monitoring (BMS)

Ok 14 modules are running now.
Unfortunately had 3 defective NTC.
Now let’s see what the next 24 hours bring in the test run.

? A question “aussiegwapo” Brett. ?
Where did you buy your connection cables? Were they already so finished or did you mount the plugs themselves to the cables.

to your problem yet:
I can only recommend you to delete the Attiny again (Arduino example Attiny EEPROM CLEAN) and rebuild with the Board Script. And then via the ESP BMS test software to check if the controller is visible with “X” in the serial console.

And you have me in the normal ESP firmware set a loop for the serial console with output of ID, volts and temperature.

Arduino-ESP8266-BMS-Controller.ino

Line ~~~ 400 +

emoncms.postData(myConfig, cell_array, cell_array_max);
influxdb.postData(myConfig, cell_array, cell_array_max);

  Serial.println(" Aufstellung Module - ID - VOLT - TEMP ");
  for (int a = 0; a < cell_array_max; a++) {
    // ANFANG - AUSGABE CELL VOLT usw module->address
    Serial.println(" Cell ID = " + String(cell_array[a].address));
    Serial.println(" Cell Voltage = " + String(cell_array[a].voltage));
    Serial.println(" Cell Temperatur = " + String(cell_array[a].temperature) + " C "); 
  //  Serial.println(" Max Cell Voltage = " + String(myConfig.max_voltage*1000));
  
    
    // ENDE - AUSGABE CELL VOLT usw
    
    if (cell_array[a].voltage >= myConfig.max_voltage*1000) {
      cell_array[a].balance_target = myConfig.max_voltage*1000; 
       max_enabled = true;
       balance_status = 4;
    } else if (manual_balance!= true) cell_array[a].balance_target = 0;
  }
  if (max_enabled!=true) avg_balance(); 
  max_enabled = false;
   Serial.println(" Aufstellung Module - ENDE ");
  //Update Influxdb/emoncms every 20 seconds
  // ANFANG - AUSGABE Übertragung 
   // next_submit = millis() + 20000;
   next_submit = millis() + 2000;
  // ENDE - AUSGABE Übertragung 
  
}

}
}//end of loop

Update: 18.11.2018

and a little problem with the 24 hour test.
Apparently I still have a problem with 2 boards.
They draw in so much power from the battery that 18650 he has over 2000mah after 12 hours. Empty is at 2v from 4.2v. Since I have to check the REG710NA-3.3 times what’s going on.

Update:
I’ve tested the REG710NA-3.3 and apparently have a short circuit in the output (not soldered clean) or they are defective. I’ll renew the dan tomorrow.

Update: 19.11.2018 for Brett
If we replace the thermister with a resister whats would be the value?
10 k NTC = 10k ohm = ca. +20C

0°C 32,65 kOhm +10°C 19,90 kOhm +20°C 12,49 kOhm +25°C 10,00 kOhm +30°C 8,06 kOhm +40°C 5,32 kOhm

Update 20.11.2018

as expected, there was a short circuit on the pins 3,4,5 at the output of REG710NA-3.3.
Once completely soldered and everything OK as it looks.

Update
now on test run with S14P4 test Pack

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