How to monitor battery status

[puta]

How can I monitor the remaining battery charge status on a battery operated ESP32 microcontroller project with re-chargable eg. 18650 battery. This is somewhat similar to battery operated handheld devices / cameras .. etc dispaly battery status. Is it done by just reading the voltage across the Battery terminal... 

Thanks for your help on this.

[sadman]

if in your project you are using LCD and by using analogue input of ESP32 easily monitor the battery voltage and can be display on LCD remains power of the battery you can find code snip by googling.

[puta]

Yes, exactly. I use TFT display in my project. Thanks for quick reply sadman !

Is monitoring the voltage across the battery terminal acurate enough?
I mean is the relationship between voltage and remaining charge is linear enough? and what voltage is considered 0V remain in the display etc..

[sadman]

Yes, exactly. I use TFT display in my project. Thanks for quick reply sadman !

Is monitoring the voltage across the battery terminal acurate enough?
I mean is the relationship between voltage and remaining charge is linear enough? and what voltage is considered 0V remain in the display etc..

you just need simple voltage divider example share which is used for 9 volt battery yes it will linear during charge show voltage as rises during charging.

[pushycat]

How can I monitor the remaining battery charge status on a battery operated ESP32 microcontroller project with re-chargable eg. 18650 battery. This is somewhat similar to battery operated handheld devices / cameras .. etc dispaly battery status. Is it done by just reading the voltage across the Battery terminal...  

Thanks for your help on this.

In addition to monitoring the voltage with a voltage divider network as suggested by "sadman" you can also put a shunt resistor in series to the Load, to monitor the current which will give a real time of juice left in the battery. But this will make it accurate but a bit complicated and difficult in coding.

[bobcat1]

Hi

for accurately monitor battery information & status you will need to use a coulomb counter,

Either use a software algorithm who process: current, temperature, voltage & battery chemistry data or use a chip from known manufactures like (TI,ST,Analog device....)

All the best

Bobi  

[sadman]

as mentioned by bobcat1 Coulomb Counter is much better solution then the simple resister divider network a good hook up instruction can be found at spark-fun webpage with code example.


https://learn.sparkfun.com/tutorials/ltc4150-coulomb-counter-hookup-guide/all#:~:text=A%20coulomb%20counter%20is%20like%20an%20odometer%20for%20current.&text=By%20counting%20the%20pulses%20and,putting%20back%20into)%20your%20battery.

https://www.analog.com/en/product-category/battery-fuel-gauge-and-coulomb-counter.html

https://www.youtube.com/watch?v=mxIrqjYCLho

sadman

[Sideshow Bob]

How can I monitor the remaining battery charge status on a battery operated ESP32 microcontroller project with re-chargable eg. 18650 battery. This is somewhat similar to battery operated handheld devices / cameras .. etc dispaly battery status. Is it done by just reading the voltage across the Battery terminal... 

Thanks for your help on this.

Somewhat a digression but a site I often use regarding battries is the  Battery University https://batteryuniversity.com/