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[Mathel]

The reason why batteries have negligeable voltage dropoff until they are almost empty is, that they are basically tiny chemical reactors, with limited fuel. This is also why you can't instantly drain them by shorting them out. It will drain them fast, but not instantly.

What happens in a chemical battery an electrochemical reaction, which deposits positive ions onto one electrode, negative ions on the other. However, the presence electric charge between the electrodes slows down the reaction, stopping it at the battery's nominal voltage.
So long as the battery is saturated with reactants, voltage will drop off only slightly, because it is the charge that is holding the reaction back, and it takes very little of the reactants to make a full charge.

When you start draining power from the battery, anode's (which from outside is considered cathode) electrons, neutralising it, and add electrons to the cathode (which from outside is considered anode), neutralising it. So the reaction continues. It can only go so fast though, so you still get a limited current.

Eventually though, reactants will start running out and the amount of products will increase so much, that it also slows down the reaction. At this point, the voltage will start dropping, as lower charge is needed to stop the reaction with the help of it's products.

[wierd]

That is correct, but the internal resistance of the cell will increase, as well as the temperature, as the battery becomes leess efficient, due to reactant depletion/ion capacity changes of the electrolyte.

That is why internal cell resistence is also measured. Temperature greatly affects the reaction rate, and also thev resistance value.

This is why a cold, or hot, battery will misreport.

[McTraveller]

Nope, phone isn't cold or anything, it's been at "room temperature" all day.  The battery is fairly old though (it's still original battery in a phone I got in 2016), so I'm sure its characteristics don't match the original design assumptions.

I almost wish battery-based devices had an engineering mode, where instead of saying how much power remains in some nebulous % charge, it gives you at least three numbers: estimated total capacity in joules (not mA-h, I hate that stupid unit because it is NOT energy unless you are at a fixed voltage), number of joules added during the last charge session, and number of joules consumed since the last charge session.

Basically I find it a violation of principle of least astonishment: showing a constant battery remaining when you're obviously consuming energy is just wrong.

Also for the curious, it now has dropped to 21% charge, which is what it's read for the past hour and a half or so.

Aside: yes I know why battery voltage is constant for a while, and why that makes it difficult to determine SOC from just voltage, and why you need something more complex than just a single voltage measurement to determine such a thing.

[None]

Man, I left my phone in my car in the cold for like two hours and now it won't hold a charge for more than a day and a half, even with minimal usage. Also pretty sure that the Turbocharge capability it has burned a bright spot into my screen.

Tablet is meanwhile like 'lol you haven't charged me in 8 days but here's 28% battery life remaining.'

[Dunamisdeos]

Tablets are weird like that. My kid has an old kindle to mess around with, and it has like 12x the battery life of my newfangled cell.

[Frumple]

I've definitely found that, for all its other problems (bugger off amazon i don't want to register stop asking), kindles are remarkably sturdy for tablets. I've fiddled with a few others and owned one other sort outright and just... none of them have held together or lasted as long as the kindles, so far. I wouldn't recommend one for someone without enough tech savvy to bypass most of the built in nuisance, but if you can handle doing an end run around amazon's junk they seem to be fairly solid workhorse tablets.

[wierd]

The paperwhite antique i got for free is a good e-reader, but not much else.

[Lord Shonus]

The Kindle Fire line is a proper tablet, but I wouldn't call the solid or durable. The screen on mine literally shattered while it was sitting still, and it was running like shit after only a year or two.

[Dunamisdeos]

Here's my WTF, it took around 4 total hours to buy and set up my new phone.

[hector13]

Did you have to build the phone yourself?

[scriver]

It's Fåntratt, the new Ikea phone

[EuchreJack]

New law in Russia: foreigners working in Russia, and their children age 7 and above will need to have themselves checked by a psychiatrist, a drug abuse therapist, and an infectious disease specialist, once every 3 months, to be allowed to stay in Russia.
They are also obliged to provide all biometric data they can give to the Russian authorities.

People who test positive for drugs, HIV, leprosy, syphilis, tubercolosis, or corona, or whom a psychiatrists deems strange, will be deported out of the country.

Foreign companies doing business in Russia are outraged. The chairman of the German-Russian chamber of commerce expects an exodus of foreign companies from Russia.


https://www.volkskrant.nl/nieuws-achtergrond/buitenlander-in-rusland-wordt-elk-kwartaal-aan-medische-en-psychische-keuring-onderworpen~bbb7e70e/

Countries of origin should start building more housing for those who will soon leave Russia. There's 12 million foreigners working in Russia.

Well, I guess Russia is going to invade Ukraine after all.  Passing laws to push out/control foreigners is a prelude to war, since they want to lock down any potential foreign spies.

[MaxTheFox]

How common are e-ink web browsers?

[Frumple]

Not, as near as I can tell from checking. They exist and seem to be functional enough, but there's not like a pile of them or anything.

[delphonso]

e-paper takes like...3 seconds to refresh, I think (maybe I'm off by an order of magnitude. 30 seconds?) So unless you're patient or really care about battery life - they're pretty rare. My mother had an ebook with 4g, though - and could browse on it, however slowly. It worked well enough to check the weather while travelling.