Hi everyone.
Can anybody tell me how to make a battery sensor temperature ? i tought about using LM35 and sticking it on the battery so i can figure out the temperature with arduino but it seem not a practical way for me because i think there must be some way to know the temperature by measuring the curent no ? anyway i am just saying ... can anybody help me how to buld one ?

 

...i tought about using LM35 and sticking it on the battery...

That's the way I'd do it. The mechanical challenge of getting good thermal contact with the battery and minimal contact with anything else is maybe the bigger problem.

And you might want to amplify the the LM35 output with an op-amp circuit. This has advantages and disadvantages, the main disadvantage being that the temperature range you can measure will become limited by the power supply voltage. For example, the LM35 will output 500mV at 50°C. If you add an amplifier at 10X gain, you'll need at least 5V from the supply. But I'm not sure how well the Arduino can handle, say, 200mV at 20°C. You might get more precision if you amplify. If you don't need great precision and the Arduino alone is good enough, don't bother with an amplifier.

 

Just use an Lm35 stuck to the battery, no need to amplify it, get the temperature straight from it at 10mV/C,

20C is 200mV,
35C is 350mV
50C is 500mV etc..

 

That's the way I'd do it. The mechanical challenge of getting good thermal contact with the battery and minimal contact with anything else is maybe the bigger problem.

Put the LM35 in a little piece of polystyrene foam and tape that to the battery. This will insulate the chip from the environment so its temperature will better match that of the battery.

 

Put the LM35 in a little piece of polystyrene foam and tape that to the battery. This will insulate the chip from the environment so its temperature will better match that of the battery.

Thank you for your answer

 

Thank you for answering me

 

That's the way I'd do it. The mechanical challenge of getting good thermal contact with the battery and minimal contact with anything else is maybe the bigger problem.

And you might want to amplify the the LM35 output with an op-amp circuit. This has advantages and disadvantages, the main disadvantage being that the temperature range you can measure will become limited by the power supply voltage. For example, the LM35 will output 500mV at 50°C. If you add an amplifier at 10X gain, you'll need at least 5V from the supply. But I'm not sure how well the Arduino can handle, say, 200mV at 20°C. You might get more precision if you amplify. If you don't need great precision and the Arduino alone is good enough, don't bother with an amplifier.

Thank you for your informations

 

Hmm . . Are the temperature sensor come in a module?