[tmaly]

If you look at the charge cycles on a typical iphone battery, it is some where around 500-600. If you look at common usage, most people use the phone enough to have to charge it once a day.

That only gives you maybe 1.5 to 2 years of time before the battery is gone.

While we are on the topic on replacing things, it would be nice if we could change out the internal flash memory. I would keep my iphone for 5 to 7 years if I could change out both the battery and flash memory.

[MontyCarloHall]

>most people use the phone enough to have to charge it once a day. That only gives you maybe 1.5 to 2 years of time before the battery is gone.

A cycle is equivalent to a full discharge/charge. Using the phone to x% battery is roughly equivalent to x% of a cycle (it’s not a perfectly 1:1 relationship, but close enough).

Most people do not use a phone to 0% battery every single day. That’s equivalent to ~8 hours of screentime on a modern phone.

The average person uses their phone for about 3 hours a day [0]. Assuming that the vast majority of people's usage is within an hour of the average, 2-4 hours of daily phone usage would translate to 25-50% of a cycle, or 1000-2000 days of a usable battery, assuming a 500 cycle battery lifespan. (In reality it would be somewhat less, since as the battery degrades over time those 2-4 hours of usage would constitute more than 25-50% of a cycle.)

[0] https://explodingtopics.com/blog/smartphone-usage-stats

[danShumway]

This is... sort of correct. Yes, most people don't use their phone 8 hours a day.

But this is a pretty cursory reading of those stats. If you actually dig into them, the majority of countries being surveyed are using their phones for more than 4 hours a day. The average person in the US uses their phone for 3 hours and 30 minutes.

A couple of takeaways:

- heavy smartphone usage inversely correlates with the wealth of the nation being talked about (this kind of intuitively makes sense, because countries like the Philippines are probably more likely to have people using their phone as their primary computer). Being able to use your phone a small amount of time each day has a small component of privilege to it, it probably means you have access to other computers.

- Even in the US, these are averages. There are people in the US who use their phones as their primary computer. There are people who travel a lot, or for whatever reason, end up using their phone more, and their batteries are very much going to be the first part of their phone that fails. The average usage in the US being 3.5 hours does not mean that the vast majority of people's usage is within an hour of the usage.

- Like you yourself said: "in reality it would be somewhat less, since as the battery degrades over time those 2-4 hours of usage would constitute more than 25-50% of a cycle." If we assume that heavy smartphone users in the US are using their phone for at least 4-4.5 hours a day (a very easy assumption if not conservative, since the average is already 3 and half hours) you're still going to be in a position where after about 2 years you're no longer going to get a full 8 hours out of a charge. Once you get to a point where a phone can't last a full 8 hour day on a single charge, you might start thinking about buying a new phone even if that's not your typical usage, because the first couple of times you forget to plug in your phone you'll stop trusting it to hold a charge.

GP is definitely wrong about how heavily people use their smartphones, but I suspect you're underestimating how heavily smartphones do get used and how big of an issue battery degrading is. I'd love to find more solid stats basically just asking people why they upgrade, but my experience matches GP's (minus the exact numbers). Battery lifespan and the cost of battery replacement is a huge component in smartphone churn. People buy new smartphones because their batteries die.

[tmaly]

I would agree with your numbers, but I would like to point out that different uses of the phone can use more energy than other uses.

This would tend to reduce the number of overall days of usable battery.

Think video recording, video editing, or heavy video playback apps. These are huge drains on the battery.

[sitkack]

They absolutely should include replaceable flash memory. Flash is both cheap, plentiful and a consumable, it wears out. It has the same qualities as battery replacement. Hell, why not combine them.

Most people would buy a new phone anyway, but these devices get obsoleted and turned into garbage, forcing people to both generate ewaste and buy things they don't really need.

Between eMMC and SD Express, there are at least two existing great options. I am not asking for doors, all this stuff can be internal by removing the back.

The issue when people discuss this, they get into weeds talking about how this or that mechanism isn't feasible, which is entirely orthogonal. You dictate the outcome, let engineers solve the problem.

[daemontus]

I don't have any scientific data for this, but my anecdotal experience is that the actual damage comes from the way the phones are used, not necessarily the absolute charge count. Here me out...

- A phone that is used a lot in the car as GPS is often charged/discharged continuously, often for hours.

- Furthermore, this often happens in very hot or cold conditions which are bad for battery charging.

- A lot of people seem to live with the perpetual 5% of battery, or generally don't care about properly charging the device. This is also terrible for longevity.

- There are other reasons why you may want to constantly charge/discharge your phone (e.g. you are making Android apps, or it's the phone where people call your place of business, etc.).

So, just to make myself clear: I completely agree that on average, batteries should last for a long time. But in practice, people often have irregular activities which appear negligible on average ("it's just a few charge cycles"), but end up damaging the battery more than regular prolonged use. But again: I'd very much like more hard data on this :)