Maybe. I’m assuming you would need to take out like a third to half the battery to have enough room for explosives.
While there is some variance in energy density between inexpensive and expensive LiIon batteries it is maybe 20%. So take out half the battery and boost the 50% life battery to 60%? Or take out a third and boost 66% to 79%. At about 80% of the predicted battery life, yeah I could buy people not noticing. Or not noticing reliably.
If a bargain basement cell phone uses LiFePO then you could probably match or near enough match by switching to LiIon.
I think a lot of cheap cellphones have poor battery life not due to batteries, but because other components are selected with an eye towards low price. So the slower CPU needs to run for an extra 40% more milliseconds to process each new email that comes in. The more expensive phone races to sleep faster and even though it uses more power during its time awake it gets back to sleep faster.
Maybe Android phones are enough of a commodity that a sufficiently motivated and resourced entity could take a specific low end phone and replace it with a high end phone with a smaller battery and make it act enough like the low end phone that nobody notices before boom time?
I hate to flip flop twice in the same thing, but I find your argument compelling too…
