3.6V cell phone batteries as power source for Arduino projects?

Other Hardware Motors, Mechanics, Power and CNC
1

Radio Shack has 3.6V cell phone batteries in stock. Is it possible to use them as power source for Arduino projects? If so, how can I charge them?

2

If you have a 3.3v arduino (nano, due) you could probably use it as a power source. You would want to add some form of over voltage protection (I've heard of using a 5.1v Zener diode to limit the voltage to 5v, but I'm not sure how those are connected or if you could get 3.4v ones, maybe another user can enlighten?) As for charging the battery, you'd probably need to look at the data sheet for the battery to see what kind of signals it expects in order to charge.

If you are using a 5v arduino (UNO, Mega, Leo, etc) 3.6v will not be able to power the arduino. You could certainly still run other parts of your project with it though.

3

jeffmorris:
how can I charge them?

buy a cell phone to charge it?

Sample of battery from Radio Shack;-

Lenmar 3.7V/1200mAh Li-ion Cellular Battery for Samsung Price: $19.99

Sample of 18650 battery

Samsung Li-Ion 18650 Cylindrical 3.7V 2800mAh Price: $9.95

18650 battery is better deal.

What you need is;-

  • good brand name battery
  • good battery charger
  • battery holder
  • batery protection PCB

The battery and charger could be easily got from amazon.

holder

protection PCB

Li-ion Battery has 4.3V when fully charged and 3.0 when fully discharged. to use with Arduino we need dc-dc converter.

We have few threads about this issue, let us know if you need help.

4

You can use a 3.6v Li-ion battery directly with a 5V Uno, just bypass the regulator. It will start at 4.2V fully charged. At that point it will run perfectly. As it discharges somewhere around the 3-4v range it will run unreliably. Your choices are to change the clock speed, only use 1/2 the capacity, or take a chance it will crash. Keep in mind the analog sampling will not be absolute, only relative to the battery voltage. If you need absolute accuracy use 2 Li-ion batts and regulator. If you don't mind an occasional crash you can use this Watchdog code to reset it automatically, or sleep and charge:

#include <avr/wdt.h>
void setup(){
Serial.begin(115200);
wdt_enable(WDTO_1S);  // reset after one second, if no wdt_reset()
}
void loop(){
Serial.println ("Point A");
delay (900);
wdt_reset();
Serial.println ("Point B");
delay (900);
while(true) ;   // oops, went into a loop
}
5

You could use a buck-boost IC chip to prevent over and under voltage.

6

protection PCB;-

  1. Range and accuracy of detection/release voltage
  • Overcharge detection voltage
  • Overcharge release voltage
  • Overdischarge detection voltage
  • Overdischarge release voltage
  • Discharging overcurrent detection voltage
  • Charging overcurrent detection voltage
  • Short detection voltage
  • Battery temperature detection voltage
  • Battery temperature release voltage
  1. Range of detection delay time
  • Overcharge detection delay time
  • Overdischarge detection delay time
  • Discharging overcurrent detection delay time
  • Charging overcurrent detection delay time
  • Short detection delay time
  • Battery temperature detection H delay time
7

What is the sleep current when using a buck-boost IC?

8

sbright33:
What is the sleep current when using a buck-boost IC?

Tough call, depends on which buck-boost IC.

For 5.0 V Arduino, we need boost IC.
For 3.3 V Arduino, we could use buck-boost IC or bulk IC if no care last 20% capacity.