Samsung Battery Thermistor (NTC) type?

[idan]

We are building a product that will be using regular samsung batteries (s5 or note 4).

We can for the life of us figure out what kind of Thermistor they are using. While the battery is in rest, the resistance between GND and NTC is 2.37 and it will not change with temp.

While charging the resistance is changing, but not in any way that helps us figuring out what thermistor it is, or maybe something else?

Measuring in 20K:

1. List item
2. 17C --> 2.85
3. 23C --> 3.04 (yes it goes up)
4. 31C --> 3.2
5. +50C -->3.3 (the most I could get)

Here are pictures of two PCB we took off the batteries.

http://i.stack.imgur.com/WAX1y.jpg

Thank you for the help!

 

[Alec_t]

Welcome to EP!
Why did you remove the PCBs? They are there to protect the battery from incorrect charging/discharging and are critical safety components to prevent fire/explosion.

 

[Amar Dhore]

Correct me if I am wrong:

What I would do is, I would create a resistance divider, with res 100ohm or 1K or 10K or 20K to Vcc and Samsung battery's one thermistor leg to ground. So with one of the above combinations, you should get a room temperature reading when the battery is at rest. So now you know what type of resistance a sensor has.