[Kirby64]

You'd be surprised the peak current demand of modern smartphones. AVERAGE current demand (not peak) of a Snapdragon 8 Gen 2 can hit 16W for short periods of time. At 3V, that's 5+ amps out of the battery. Worse if you account for efficiency, and even worse if you account for other power draws such as camera, display, etc etc. Running at 3-4C for short bursts is not out of the question.

[jacquesm]

That I readily believe. But in a well designed system (designed for longevity) you'd never see such discharge currents in a sustained manner and even short bursts are better served by capacitors (charged at a lower constant current) close to the consumer than by batteries. And that's why you'll see voltage regulators and large banks of capacitors right next to the CPU (besides compensation for line losses and stability of the supply, which with rapid wide load variations would cause all kinds of problems for the logic).

But in for instance a vehicle or an e-bike you'd rarely see batteries drained faster than the spec, not if you want to use your expensive device for a while.

[Kirby64]

Keep in mind, when I say 'short bursts', I mean on the time scale of seconds. No capacitor bank is going to be capable of supplying current for that long; especially not one put in a phone. In most cases, the restriction is inevitably heat based (how long can I run this before thermals cause me to need to throttle) and the power supply is pushed to be able to handle it.

EV batteries and e-bikes are a whole different animal than what is used in cell phone battery tech.

Also, is 2.0V bad for the battery? It's not great, but it's not Voc of 2.0V. It's Vsc, essentially. Which is a very different quantity.