This time the journey / research, this started by checking product specifications of a Samsung battery for mobile phones. EB-BG903BBE
At product description there is a reference, that within the battery there is a miniature Strap
PolySwitch.
The next question this coming in mind, can we precisely measure Ohms resistance of such parts?
In theory this thing will look as a sort when this is not tripped.
From the other hand, this thing has 99% similarity to
a current shunt.
2026 Littelfuse, Inc. | This makes it clear.
Most sensitive to low currents Resettable Fuse this is at
0.03 ~ 0.07 Ohms 1.9 to 4A protection range.
Long story in short:We have a very low electrical resistance
Two wires measurement
And all handheld multimeter, they are blind so to offer measurable confirmation due a measurement.
Lowest 300 or 600 Ohms range, this cannot resolve / measure, such low resistance values.
Two months ago,
May 2026, I made to my self
a special gift.
FLUKE
TL2X4W PTII 4W test lead for FLUKE 8846A 6 1/2 DMM.
Due this combination, 10 Ohm DMM range + Four wire specialized test leads, I can now measure with high precision, anything within the
Milli-Ohm quantities.
In conclusion, PPTC Resettable Fuses specifications verification, this is impossible due low cost tools.

If you are after to get to know the entire truth?
This ITTSB article below, this offering true clear answers.
https://www.ittsb.eu/forum/index.php?topic=2300.0