Android battery is 5+ years old, is that a problem?

So I have an Android (an HTC One X) from the year 2012 that has never had its battery replaced. It still functions just fine, and it never occurred to me to replace the battery - until I read that smartphone batteries aren’t even meant to last longer than a year.
Is there anything wrong with using the battery indefinitely as long as it has no issues? Or am I pushing something dangerous here?

Cellphone batteries are generally rated for around 1,000 load cycles (I.e. 0-100%, not your everyday topping up the battery.), but they usually lose capacity over time.

They’re $6 on Amazon. I’d get one.

In my experience, when batteries do finally go bad, they tend to do so in very inconvenient ways.

If it’s still holding a charge adequately for your usage, there’s absolutely no reason to replace the battery. Li-ion batteries degrade both per cycle and over time whether they’re discharged or not, but this aging is just a decrease in their charge-storing capacity. It’s not anything dangerous, like the cell phone bursts into flames stories you read occasionally. While those are related to defective batteries, the defects in question aren’t age-related.

I agree that there’s no reason to replace a properly functioning battery. Batteries degrade over time but it also depends on how it’s used. And not all batteries are equal; some just last longer than others. If your battery is functioning well for more than 5 years then your device was well cared-for and your battery was well-made. Hang onto it.

Except as far as I can tell, the phone is sealed, so replacing the battery requires you to crack it open. Usually that involves specialty tools or you can go to a shop and have them do it. But either way, it’s not going to cost only six bucks.

And another thing. The devices I have (notebook computer, iPhone, etc) all have a way to check the “battery health”, meaning how much a full charge today compares to when the battery was new. Presumably there is a way to do this on an Android phone. If the test shows the battery is relatively healthy, I wouldn’t worry about it.

(Also, just to be clear, the OP said that smartphone batteries were meant to last only a year, but that is incorrect.)

Lithium ion batteries are small, lightweight, and store a lot of energy for their size. This makes them great for things like cell phones, tablets, and laptops.

What they suck at is longevity.

Lithium ion batteries start dying from the moment they are made. Compared to other battery chemistries, lithium ion batteries always die an early death, pretty much no matter what.

That said, they typically last longer than a year. After about 3 to 5 years they have often lost enough capacity that many users will want to replace them. However, if the OP’s phone has enough capacity to still be fully functional for what the OP needs, then I can’t see any reason to replace it. I have a laptop that is roughly the same age, and while the battery doesn’t last anywhere near as long as it once did, it works well enough for me and I have no intention of replacing it either.

Heat kills lithium ion batteries. If your phone battery is only lasting a year, chances are that heat is the reason why. Maybe you leave the phone out in the sun, or maybe the phone tends to run a bit hot and you keep it in your pocket where the heat tends to build up inside of it. Keep the battery cooler (as close to room temperature as possible) and it will last a lot longer.

Just to add cycle life for Li-ion batteries doesn’t mean shit. It was a hold over from the days of Ni-Cd and Ni-mh where it did and became a standard and why it is used for Li-ion. Basically cycle life for Li-ion is just how long it is expected to last in time, and estimate tyhe number of cycles it would have during that time to give a time in number of cycles.

Big factors for shortening the life of for Li-ion is time, heat, time spent at low discharge states (especially under 20% - don’t leave it at low states the battery eats itself very fast, recharge ASAP), time spent at high charge (typically over 80% - though time at low is worse).

Do you have a cite for this? The very good Battery University seems to disagree, with some charts showing capacity graphed over charge cycles. Obviously other things matter too:

But I think it’s erroneous to claim that “cycle life doesn’t mean shit.”

You’re right, I didn’t notice the little wires in the Amazon image. Why do they make phones like that?

I’d still think about being prepared. While it’s working fine now, it’s definitely on the elderly side and it’s likely that the only place to find a new battery is online, then it may take more time to find someone to do the replacement. It could be a multi-day problem.

Batteries go bad in different ways, but the way it usually works for me is that I find that my phone dies after 5 minutes of being unplugged from the charger… on the first day of vacation.

There are step-by-step instructions available here: https://www.ifixit.com/Guide/HTC+One+X+Battery+Replacement/30964. Looks a little involved but only needs a fine screwdriver and a plastic prying tool.