Replacing 3.7v battery questions...

Thread Starter


Joined May 3, 2016
Hi there.
The device uses
E505068 120503
1800mah 3.7V 6.66Wh
It has 3 connections(wires) to the board of the device(Cutepad Q5) - black, yellow and red.
I see the same battery in my country but it has only 2 wires.
Maybe third is some heat protection. I am scaren on my own to make the changes and am asking for advice :)
The woman is taxi driver and uses it for "taking addresses"

Thanks in advance!


Joined Sep 9, 2010
It might be heat sensing or a way to isolate two cells for separate charge control. A quick search didn't turn up anything.

Thread Starter


Joined May 3, 2016
Do i think right ?
Maybe the original battery is better than the possible new which i can take with 2 links, but the new is also a option?
I can purchase the new one and try to full charge it and see if it gonna goes hot or not? If not i can make full discharge though some application with video and if everything is fine totally everything is ok?

Nice day;

What if i take only controller from old battery and connect it to new cells?
Last edited:
Not really sure what your question is?

The third wire COULD be:
1) Thermister which is common in a Li-Ion battery. Although there are usually 4 terminals.
2) Some sort of battery ID from an IC to even a simple resistor.


Joined Aug 16, 2010
The third wire in a Li-Ion battery is normally from a thermistor that is mounted inside the battery to monitor the temperature on the Li-Ion cells. The charger uses this to disable charging if the cells get too hot.