Reply
 
Thread Tools Display Modes
  #1  
Old 03-23-2020, 11:28 PM
Velocity is offline
Guest
 
Join Date: Jun 2014
Posts: 16,999

"Smartphone batteries only meant to be recharged 730 times" - what if many more times?


So, supposedly smartphone Li-On batteries are only meant to be recharged 730 times - in other words, once a day, for two years.

What if someone takes it to 1,200, or 2,000, or even more recharges? What happens to the battery (other than it getting weaker and weaker?) Does it become more hazardous?
  #2  
Old 03-23-2020, 11:37 PM
beowulff's Avatar
beowulff is offline
Member
 
Join Date: May 2001
Location: Scottsdale, more-or-less
Posts: 17,295
Quote:
Does it become more hazardous?
Not really.
They tend to swell up, and that may damage your phone, but the end-of-life failure mode is not “catch on fire."
  #3  
Old 03-23-2020, 11:43 PM
DPRK is offline
Guest
 
Join Date: May 2016
Posts: 4,809
From personal experience (not rigorous analysis), the capacity slowly fades away and the battery becomes increasingly unreliable, but I haven't had one explode on me and there is no reason not to use them for a couple of thousands of cycles if you can handle the moderate decrease in capacity.

Also, "A 2015 study by Andreas Gutsch of the Karlsruhe Institute of Technology found that lithium-ion battery lifespan could vary by a factor of five, with some Li-ion cells losing 30% of their capacity after 1,000 cycles, and others having better capacity after 5,000 cycles" which suggests that a slightly worn-out high-quality battery beats a fresher but crappy battery.
  #4  
Old 03-24-2020, 02:34 AM
Alessan's Avatar
Alessan is offline
Guest
 
Join Date: Jul 2000
Location: Tel Aviv
Posts: 25,374
What does a "cycle" mean? From 0% to 100%? How often does that happen, really? I mean, my phone is almost always on its wireless charger, so most of the time it's charging from 99% to 100%. Does that count as a full cycle, or just as 1% of a cycle?
  #5  
Old 03-24-2020, 06:00 AM
ftg's Avatar
ftg is offline
Member
 
Join Date: Feb 2001
Location: Not the PNW :-(
Posts: 21,699
Why is this a question at all? I see something like "Smartphone batteries only meant to be recharged 730 times" and I immediately know it's woo.

1. The specfic number. No way is anything factual in this context that specific. Maybe a range like 500-1000 or some such. But 730? Come on, that's clearly bull crap.

2. There isn't a single, magic, one model of cell phone batteries. They come in all sorts of sizes, capacities, quality control. There's a lot of variation in the nuanced technology in putting these together.

It's like saying "All gas powered vehicles get 27mpg."

Ergo, it is so obviously total nonsense no rational person would buy it for a second.

Yes, rechargeable batteries don't last forever. There are a large number of factors that go into how long they last. Number of rechargings is one component of this. But even for that part how deep of a discharge, etc. factors in significantly.

The older a battery gets, the more likely it is to fail. Once in a while the failure mode is not good. So a hazard ensues. And that is quite uncommon. But, again, there is no magic number.

Last edited by ftg; 03-24-2020 at 06:01 AM.
  #6  
Old 03-24-2020, 06:50 AM
MikeS is offline
Charter Member
 
Join Date: Oct 2001
Location: New London, CT
Posts: 3,930
Quote:
Originally Posted by ftg View Post
1. The specfic number. No way is anything factual in this context that specific. Maybe a range like 500-1000 or some such. But 730? Come on, that's clearly bull crap.
I also noticed that it's exactly equal to one charging per day for two years, which is awfully convenient.
  #7  
Old 03-24-2020, 10:06 AM
Do Not Taunt is offline
Guest
 
Join Date: Apr 2006
Location: Seattle
Posts: 2,267
The most common symptom I've seen with old batteries is not just that they hold their charge less well, but they also report their charge less well. Ie, the phone (or laptop, whatever) will happily report 30%, and then die 10 seconds later. Once the charge percentage starts behaving erratically, it's time to replace the battery (or phone.) Not because it's dangerous, but because it's irritating.
  #8  
Old 03-24-2020, 10:22 AM
kanicbird is offline
Guest
 
Join Date: May 1999
Posts: 20,183
Cycle life is a old industry standard for a different type of battery chemistry, that of NiCd or Ni-mh. It does not directly apply to Li-ion, but it is s standard, and why it is still used.

The main factors that affect life are:

1 The temperature the battery is at at all times and all state of discharge it's at that time.

2 The date of manufacture (it starts to self destruct from the time it's made, slowly eating itself away)

3 The time it spends at any particular state of discharge (near 0% is the worst of the worst, Full charge is also not the greatest, 40% is optimal)

4 Artificial limits, almost all Li-ion rechargeable batteries have software limits 100% is not true 100%, 0% is not true 0%, the battery could be pushed more in either direction but at the expense of life.

From the above it can be estimated how long a phone battery can last as how people will use it, and consider one recharge per day, so cycle life is estimated at 730 cycles for a battery that should last 2 years.

For quite some time devices have extended life in devices that are often run at 100%, that will let it drift the charge down to 90% or so (laptops commonly do this), Smartphones if they know the charging habit will recharge to 80% then wait at 80% till it's time to bring it to 100% which is when it thinks you will get up in the morning.

Last edited by kanicbird; 03-24-2020 at 10:23 AM.
  #9  
Old 03-24-2020, 01:11 PM
Mr Quatro is offline
Guest
 
Join Date: Apr 2013
Posts: 1,133
Are rechargeable batteries expensive?
  #10  
Old 03-24-2020, 01:26 PM
DPRK is offline
Guest
 
Join Date: May 2016
Posts: 4,809
Quote:
Originally Posted by Mr Quatro View Post
Are rechargeable batteries expensive?
I don't consider high-quality automotive/marine or lithium-metal-phosphate batteries particularly cheap, but with smartphone batteries you have the additional problem of potential DRM as well as needing precise dimensions and a specific connector, preventing you from simply putting in any old rechargeable battery.
  #11  
Old 03-24-2020, 03:06 PM
ftg's Avatar
ftg is offline
Member
 
Join Date: Feb 2001
Location: Not the PNW :-(
Posts: 21,699
Quote:
Originally Posted by Mr Quatro View Post
Are rechargeable batteries expensive?
Like the responses to the OP, it also depends.

The phones I've had all have easily replaceable batteries and the models were produced in enough numbers that quite reasonably priced replacements are easily available.

But we're moving into a "completely sealed up" world for smartphones. Apple was one of the first to make replacing batteries hard, and then even harder. For most people once the battery in the latest iPhones dies, it's a dead phone.

DRM has been mentioned as one aspect of enforcing premature phone death used by some makers. Although DRM isn't the term I'd use. There's an encoded chip in the battery that the phone checks to verify a "legitimate" battery is installed. And if no such batteries are availble to the public outside of things like warranty replacement at manufacturer facilities, that's not so good. Esp. for tinkerers like me.

So: the answer is from cheap to basically not for any price.
  #12  
Old 03-24-2020, 03:53 PM
beowulff's Avatar
beowulff is offline
Member
 
Join Date: May 2001
Location: Scottsdale, more-or-less
Posts: 17,295
I should point out that pretty much every mall in the country has a kiosk that will replace any iPhone battery for $75 or less...
  #13  
Old 03-24-2020, 06:00 PM
Darren Garrison's Avatar
Darren Garrison is offline
Guest
 
Join Date: Oct 2016
Posts: 13,382
Quote:
Originally Posted by ftg View Post
But we're moving into a "completely sealed up" world for smartphones. Apple was one of the first to make replacing batteries hard, and then even harder. For most people once the battery in the latest iPhones dies, it's a dead phone.
Europe may come to the rescue.
  #14  
Old 03-24-2020, 06:08 PM
Tastes of Chocolate is offline
Guest
 
Join Date: Aug 2003
Location: slightly north of center
Posts: 4,780
Quote:
Originally Posted by Mr Quatro View Post
Are rechargeable batteries expensive?
I've replaced mine, in a Samsung phone, twice in 4 years, once just recently. So I'm right on track for a 2 year life span. Batteries are under $25, and at least in a Samsung, take about 10 minutes, if you have to read the instructions.

I replace my battery when I have to charge it so frequently that I actually have to occasionally close down the data functions of the phone, so that it can act as a phone in case I need one (phone functions take WAY less power than anything involving data transfer).
__________________
2 + 2 = 5, for very large values of 2
  #15  
Old 03-24-2020, 08:56 PM
wolfpup's Avatar
wolfpup is online now
Guest
 
Join Date: Jan 2014
Posts: 11,541
Quote:
Originally Posted by Alessan View Post
What does a "cycle" mean? From 0% to 100%? How often does that happen, really? I mean, my phone is almost always on its wireless charger, so most of the time it's charging from 99% to 100%. Does that count as a full cycle, or just as 1% of a cycle?
To the best of my understanding, comparing batteries of equal quality, charging lifetime depends on the amount of time actually spent charging -- i.e.- charging from 99% to 100% every night is very roughly equivalent to charging from 1% to 100% nearly 99 times. My wonderful old "dumb" Motorola flip phone had a battery that lasted for many weeks before needing to be recharged. Since these aren't available any more I now have a low-end Samsung smartphone whose battery expires much more quickly because of all the stupid things it does that I don't need. No, Samsung/Google/Android, I don't want to watch the current NHL game live, I don't want to play Angry Birds, and I don't want to update 37 apps that I never use, but I MAY want to call 911 because I just fell down the stairs and can't get up!
  #16  
Old 03-24-2020, 09:14 PM
wolfpup's Avatar
wolfpup is online now
Guest
 
Join Date: Jan 2014
Posts: 11,541
Quote:
Originally Posted by Tastes of Chocolate View Post
I've replaced mine, in a Samsung phone, twice in 4 years, once just recently. So I'm right on track for a 2 year life span. Batteries are under $25, and at least in a Samsung, take about 10 minutes, if you have to read the instructions.
Good to hear. I'm about to replace the battery in my Kindle, which has been good for many years (it was one of the very first Paperwhite models). As an aside, be careful about getting the exact model number of your Kindle and make sure the battery matches. For the Paperwhite, for instance, there are at least two different batteries depending on the generation, which look almost alike but have a different number of connectors offset from the original configuration -- either 3 or 4 connector tabs. They are NOT compatible!

Quote:
Originally Posted by Tastes of Chocolate View Post
I replace my battery when I have to charge it so frequently that I actually have to occasionally close down the data functions of the phone, so that it can act as a phone in case I need one (phone functions take WAY less power than anything involving data transfer).
Exactly my point above, although in a smartphone many of those power-consuming functions cannot be turned off.
  #17  
Old 03-24-2020, 11:31 PM
zbuzz is offline
Guest
 
Join Date: Jul 2001
Posts: 1,289
Quote:
Originally Posted by Alessan View Post
What does a "cycle" mean? From 0% to 100%? How often does that happen, really? I mean, my phone is almost always on its wireless charger, so most of the time it's charging from 99% to 100%. Does that count as a full cycle, or just as 1% of a cycle?
One cycle is charging 100% of the battery capacity, but it doesn't have to happen in one continuous charge. So if you use 25% of your battery for four days straight and charge it back up to 100% every night, that's one charge cycle.
  #18  
Old 03-25-2020, 08:01 AM
Xema is offline
Guest
 
Join Date: Mar 2002
Posts: 12,464
Quote:
Originally Posted by AmyPang View Post
Technically, Lithium-ion batteries use chemical processes to generate power ...
True of almost every device that goes by the name of battery.
  #19  
Old 03-25-2020, 08:04 AM
Alley Dweller's Avatar
Alley Dweller is offline
Guest
 
Join Date: Feb 2011
Posts: 4,570
Quote:
Originally Posted by AmyPang View Post
So, it's better to change battery when you see bad symptoms on your battery
Given that cell phone batteries are in a sealed case that you can't easily look inside, what symptoms should I be looking for?
  #20  
Old 03-25-2020, 08:41 AM
ftg's Avatar
ftg is offline
Member
 
Join Date: Feb 2001
Location: Not the PNW :-(
Posts: 21,699
Quote:
Originally Posted by Alley Dweller View Post
Given that cell phone batteries are in a sealed case that you can't easily look inside, what symptoms should I be looking for?
The main symptom is that they don't hold a charge long.

One complication is that people keep adding more and more apps that have more features involving background or periodic activity. These add drain to the battery and may make it appear that the battery is going bad.

One way to differentiate this is how well the phone holds a charge when powered down. When new, charge the phone completely. Power it down. Wait a fixed time like a day. Verify that it is at or near 100%. Once or twice a year repeat. When the value starts to drop noticeably below 100% on one of these tests, you know it is going south. To do this right, you really need to leave it powered off for more like a week to test things. But for some reason a few people don't like leaving their phone off that long.

So another way to differentiate is to back up your phone, do a factory reset, and install only the most basic features you need. Use it for a while and see if that helps holding charge. Then you can restore your phone from the backup. Maybe cull as many apps as possible while you're at it.

(My doctor was complaining at how slow their phone was getting. Was considering getting a new one. All while flipping thru page after page after page of apps on the phone looking for the one they wanted to show me. Um, the phone isn't slower. There's way too many apps on it.)

Note that not all cell phones are in a sealed case. So swelling can be checked for those. But by then the short charge holding time is likely apparent.

Last edited by ftg; 03-25-2020 at 08:43 AM.
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 05:39 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2020, vBulletin Solutions, Inc.

Send questions for Cecil Adams to: cecil@straightdope.com

Send comments about this website to: webmaster@straightdope.com

Terms of Use / Privacy Policy

Advertise on the Straight Dope!
(Your direct line to thousands of the smartest, hippest people on the planet, plus a few total dipsticks.)

Copyright 2019 STM Reader, LLC.

 
Copyright © 2017