Some of you know, I really like lithium ion batteries

*shocked*

Shut it! This is a short post, I don’t need you hamming up the works.

Just wait till I show up in your videos….

You wouldn’t….

Hello….

Oh hell…..

Ok, lets not worry about that now.

I picked up a pretty sweet haul of batteries this week.

22lbs. I counted 107 2cell packs. 214 cells to check out. This is great, but I have a single opus charger that can do 4 cells at a time.

So 214 cells will take some time to process. I have done that game. So I wanted to do more cells. There are examples online of doing this with arduino’s and what not and since I am big fan of arduino’s anyways I decided to give that a shot. I built it out initially with an arduino uno. Using the awesome guidance of Adam Welch. If you don’t know who Adam is, you gotta check out his work.

Website: http://adamwelch.co.uk/

Youtube: https://www.youtube.com/channel/UCm5sG3-BXQZfVy3st2T_XKg

His work I used for this is here.

I modified the code a little as I didn’t have that screen. I have a 20×4 screen. I also updated mine to calculate the voltage reference from the internal 1.1v reference.

/* * Battery Capacity Checker * Uses Nokia 5110 Display * Uses 1 Ohm power resister as shunt - Load can be any suitable resister or lamp * * YouTube Video: https://www.youtube.com/embed/qtws6VSIoYk * * http://AdamWelch.Uk * * Required Library - LCD5110_Graph.h - http://www.rinkydinkelectronics.com/library.php?id=47 */ #include <LiquidCrystal_I2C.h> #define gatePin 2 #define highPin A0 #define lowPin A1 boolean finished = false; int interval = 5000; //Interval (ms) between measurements float mAh = 0.0; float shuntRes = 1.0; // In Ohms - Shunt resistor resistance float current = 0.0; float battVolt = 0.0; float shuntVolt = 0.0; float battLow = 2.9; LiquidCrystal_I2C lcd(0x27,20,4); unsigned long previousMillis = 0; unsigned long millisPassed = 0; void setup() { analogReference(INTERNAL); Serial.begin(115200); lcd.init(); //initialize the lcd lcd.backlight(); //open the backlight Serial.println("Battery Capacity Checker v1.1"); Serial.println("battVolt current mAh"); pinMode(gatePin, OUTPUT); digitalWrite(gatePin, LOW); lcd.setContrast(68); lcd.clear(); lcd.print("Battery"); lcd.print("Check"); lcd.print("Please Wait"); lcd.print("AdamWelch.Uk"); delay(2000); lcd.clear(); } void loop() { voltRef = readVcc() / 1024.0; Serial.print("Volt Ref: "); Serial.println(voltRef); battVolt = analogRead(highPin) * voltRef / 1024.0; Serial.print("Batt Vol: "); Serial.println(battVolt); shuntVolt = analogRead(lowPin) * voltRef / 1024.0; Serial.print("Shunt Val: "); Serial.println(shuntVolt); Serial.println(); Serial.println(); /* Serial.print(battVolt); Serial.print("\t"); Serial.print(current); Serial.print("\t"); Serial.println(mAh); */ if(battVolt >= battLow && finished == false) { digitalWrite(gatePin, HIGH); millisPassed = millis() - previousMillis; current = (battVolt - shuntVolt) / shuntRes; mAh = mAh + (current * 1000.0) * (millisPassed / 3600000.0); previousMillis = millis(); lcd.setCursor(0,0); lcd.print("Discharge "); lcd.setCursor(0,1); lcd.print("Volt:"); lcd.print(battVolt); lcd.print("v "); lcd.setCursor(0,2); lcd.print("Current:"); lcd.print(current); lcd.print("a "); lcd.setCursor(0,3); lcd.print(mAh); lcd.print("mAh "); lcd.print("Running "); } if(battVolt < battLow) { digitalWrite(gatePin, LOW); finished = true; lcd.clear(); lcd.print("Discharge"); lcd.print("Voltage:"); lcd.print(battVolt); lcd.print("v"); lcd.print(mAh); lcd.print("mAh"); lcd.setCursor(0,1); lcd.print("Complete"); } delay(interval); } long readVcc() { long result; // Read 1.1V reference against AVcc ADMUX = _BV(REFS0) | _BV(MUX3) | _BV(MUX2) | _BV(MUX1); delay(2); // Wait for Vref to settle ADCSRA |= _BV(ADSC); // Convert while (bit_is_set(ADCSRA,ADSC)); result = ADCL; result |= ADCH<<8; result = 1126400L / result; // Back-calculate AVcc in mV return result; }

Next step is to add a “charging” function with a tp4056 so I can charge then discharge.

Amazon – 5 for 6.95

Ebay – 10 for 4.95

Aliexpress – 10 < 2 bucks.

Once that is working I should be able to add a couple more modules. I have been really looking towards doing something with Brett Wattys 8 module charger. That things is INTENSE!!!

If you want to see all the info check out the secondlifestorage forum.

https://secondlifestorage.com/t-Brett-s-Arduino-8x-Smart-Charger-Discharger

He also has a portal he is setting up to help aggregate some numbers on how many cells the community has recycled.

Until later!!!

bye!!!!