AA cell discarge anaylsis using the Arduino and GNUPlot.


Download the Arduino sketch and bash scripts for use with GNUPlot here:
Tar format: Arduino_battery_tester.tar.gz MD5Sum: ce0ed75b489310d1494745310d09d8bb
Zip format: Arduino_battery_tester.zip MD5Sum: 482afffb6ec819d5c826c5019dad512b

The discharge current for all tests is 400mA at 1.1V A constant current discharge circuit would have advantages. Producing a sharper fall-off curve. But the relative results obtained here are valid indicators of duds.

Take a look at the cells under test................



Discharge test result:


Tried charging these cells again. The charger rejected all attempts to charge these cells now.
I still ran the discharge test again but swapped the order of cells just to verify the
one relatively good (but still pants) cell:


The cells under test:


Discharge test result:
Notice the rise in voltage at the start. These cells do get warm and I suspect the initial rise in temperature increased cell output.


The cells under test:


Discharge test result:


Comments

Hello Nick, I am Niels from

Hello Nick, I am Niels from the Netherlands and i watched your internet movie "Using a HD44780 16x1 LCD with the Arduino LiquidCrystal library" and i did work for me too. Thanx for that. Now I'm experimenting with the scroll commando. I only get it work on half the display when i set it to 8x2 instead of 16x2. Is it possible to use the hole display bij editing the code? Im now using: /* LiquidCrystal Library - scrollDisplayLeft() and scrollDisplayRight() Demonstrates the use a 16x2 LCD display. The LiquidCrystal library works with all LCD displays that are compatible with the Hitachi HD44780 driver. There are many of them out there, and you can usually tell them by the 16-pin interface. This sketch prints "Hello World!" to the LCD and uses the scrollDisplayLeft() and scrollDisplayRight() methods to scroll the text. The circuit: * LCD RS pin to digital pin 12 * LCD Enable pin to digital pin 11 * LCD D4 pin to digital pin 5 * LCD D5 pin to digital pin 4 * LCD D6 pin to digital pin 3 * LCD D7 pin to digital pin 2 * LCD R/W pin to ground * 10K resistor: * ends to +5V and ground * wiper to LCD VO pin (pin 3) Library originally added 18 Apr 2008 by David A. Mellis library modified 5 Jul 2009 by Limor Fried (http://www.ladyada.net) example added 9 Jul 2009 by Tom Igoe modified 22 Nov 2010 by Tom Igoe This example code is in the public domain. http://arduino.cc/en/Tutorial/LiquidCrystalScroll */ // include the library code: #include // initialize the library with the numbers of the interface pins LiquidCrystal lcd(12, 11, 5, 4, 3, 2); void setup() { // set up the LCD's number of columns and rows: lcd.begin(8, 2); // Print a message to the LCD. lcd.print("hello, world!"); delay(1000); } void loop() { // scroll 13 positions (string length) to the left // to move it offscreen left: for (int positionCounter = 0; positionCounter < 13; positionCounter++) { // scroll one position left: lcd.scrollDisplayLeft(); // wait a bit: delay(150); } // scroll 29 positions (string length + display length) to the right // to move it offscreen right: for (int positionCounter = 0; positionCounter < 29; positionCounter++) { // scroll one position right: lcd.scrollDisplayRight(); // wait a bit: delay(150); } // scroll 16 positions (display length + string length) to the left // to move it back to center: for (int positionCounter = 0; positionCounter < 16; positionCounter++) { // scroll one position left: lcd.scrollDisplayLeft(); // wait a bit: delay(150); } // delay at the end of the full loop: delay(1000); } What is a good code to use for getting it work on the hole screen. Best regards, Niels from The Netherlands