The two big issues with batteries are how long a battery lasts, in years, before it needs to be replaced (battery lifespan) and the amount of time a device runs before it needs to be recharged (battery life). This page addresses each.
All Lithium-Ion batteries can only be charged and drained a certain number of times. Each charge limits the maximum power capacity that the battery can store. That is, each charge destroys the battery capacity, just a little bit. Thus, batteries lose storage capacity over time.
Two things that are useful to know about a battery, on an ongoing basis, are the maximum charge capacity and the number of charge cycles it has gone through. Both give you an idea of how old your battery is. Not ond in terms of years/months but old in terms of its expected life span.
The maximum charge capacity is a percentage of the original out-of-the-box charge capacity. On a new battery, it should be 100%. Note that this percentage is different from the percentage typically displayed. For example, if the original design capacity was 6,000mAh and the battery now can only store 4,000mAh (perfectly normal wear and tear) it has lost one third of its original capacity. A computing device, however, will report that the battery is 100% charged when its capacity is 4,000mAh. If your device does not last as long on a "full" charge, this is why.
Batteries last the longest (total lifetime in years, not just making it through the current day) when operating between 30 and 80% charged. Keeping a Lithium Ion battery fully charged at all times shortens its lifespan. A laptop that is plugged in all the time, should be set to never charge over 80% (maybe even 70%). Lithium-Ion batteries are under the most strain internally when they are fully charged or completely empty. They are the happiest at 50 percent charge. When storing a device for a long time without using it, do what you can to prevent the battery from fully draining.
Very high temperatures (above 95 degrees F) can permanently degrade battery capacity. If a device gets noticeably hot while charging, unplug it.
Fast charging degrades Lithium-ion batteries more rapidly than the relatively slow 5-watt chargers of old.
A Brand-X charger could damage the battery. Chargers differ in the controls that limit the amount of current delivered and stop a device charging when the battery is full.
An off-brand charger might not have such rigorous safety settings. If too much current is delivered to a battery it can leadi to degradation.
FYI: Charging a phone from a laptop computer does not damage the battery. This does a slow charge which, in general, is a good thing. Leo Notenboom has a good introduction
to the concepts of Volts and Amps here Why Does My Phone Charge Slowly on Some
Chargers? (Nov 15, 2023)
FYI: A smartphone battery typically works at optimal capacity for roughly two to three years.
EXTENDING THE LIFESPAN OF A BATTERY (IN YEARS)
- Windows does not have a feature to limit the charge of a battery
- Lenovo laptops have offered software that lets you set the maximum charge percentage for years.
The software is now called Lenovo Commerical Vantage. It used to be called Think Vantage. Lenovo also has laptop software that lets you see the battery temperature
- Dell has a Power Manager app that I have read lets you set a charging threshold. Their description of the software however is useless.
- HP as a HP Battery Health Manager but it only works on some HP business laptops.
- Asus has a MyAsus app that I have read lets you set a charging threshold. Its a huge app, over 300MB with many many features.
- If you know of other software to limit the battery charge or display the battery temperature, let me know.
- As a rule, Android devices can not be set to stop charging at anything less than 100%. One exception are Sony phones which have been able to do this since at least 2014. See this Reddit post from June 2023: So glad we can now stop charging at 80%
Samsung also allows this (see below).
- Android 14 on a Pixel offers Adaptive Battery Charging to prolong the life span of the battery. This is a configurable option at:
Settings -> Battery -> Adaptive Charging
The phone spies on you to learn your charging habits, a process that takes about two weeks. Then, when the phone expects that a charging session will be long, it delays charging the battery up to 100% until an hour before it expects the charging session to end. Again, the less time a battery spends 100% charged, the better. The Google writeup says this is a Pixel-only feature.
- Samsung: Settings -> Battery and device care -> Battery -> More battery settings
The Protect battery option limits charging to 85%. You can even schedule battery protection to turn off on the days when you normally need a full charge. The scheduling is at
Settings -> Modes & Routines -> Routines. Like Google and Apple, Samsung has an Adaptive battery feature that limits full charging based on your habits.
- While Android may not let you manually set a battery charge limit, there is an automatic, non-configurable option on Pixel phones that stops charging at about
70%-80%. See Get the most life from your Pixel phone battery for details. This kicks in when
the phone detects
-- Continuous charging for more than a few hours under high temperatures
-- Continuous charging for more than several days
- For cycle count and battery wear: Android devices are all different, so the best way to see if an Android device displays this information is to search the settings for "battery". In October 2023, a pixel phone running Android 13 did not display this information. Another pixel phone running Android 14 also did not show it. An Android tablet running Android 10 showed the battery capacity in mAh, but not the charge cycles. All different.
iOS, iPhone, iPad
- The iPhone 15 was the first iPhone that allowed users to stop a battery charge at less than 100%.
- September 22, 2023: How to turn on 80% charging limit on the iPhone 15 to save battery health by June Wan for ZDNet. Finally finally finally, some iPhones get a feature that laptops (Lenovo at least) have had for years and years.
Settings -> Battery -> Battery Health & Charging -> Optimized Battery Charging -> turn on "80% Limit"
- To see how much charge an iPhone can currently take (vs. when it was new)
Settings -> Battery -> Battery Health & Charging -> Maximum Capacity percentage
Note that this information is not available on iPads.
- Cycle Count: While, the maximum capacity percentage (above) is the more important number, it can also be helpful to know how many charge cycles a
device has been through. I have read that an iPhone is designed to keep 80 percent of its original capacity for up to 500 charge cycles before the battery is
considered worn. Not that it won't work at 501. iPhones did not display the Cycle Count until the iPhone 15 where you can see it with:
Settings -> General -> About -> Cycle Count
To see this on older iPhones, you can use the Mac app CoconutBattery
This Reddit article from 2019 has a hack
to find the Cycle Count in the Analytics data that iOS collects.
- November 14, 2023: Jared Newman published instructions for using a smart plug and the iOS shortcuts app to limit how full the battery is charged: How to limit iPhone charging levels with a smart plug. His example uses
a TP-Link Kasa plug and he starts charging at 80% and stops at 85%. What if you want a full charge? He says to just plug the iPhone into a different charger. He does
no say anything about iPads.
- To have the battery percentage always displayed: Settings -> battery -> battery percentage
note that older iPhones (11,12,13) must be running iOS 16.1 for this
- iOS 13 and later have an option to optimize the charging of the battery with the intention of extending the life span of the battery. See About Optimized Battery Charging on your iPhone from Apple. They say it was published September 21, 2023, but that is not true. I first ran across this article in January 2022. Apple does exactly what Google does, the phone takes some time to learn your charging habits and then stops a re-charge at 80% for a while, only finishing the re-charge up to 100% just before it expects you to unplug the device. The option is at
Settings -> Battery -> Battery Health & Charging -> Optimized Battery Charging
This must be an iPhone only thing, there is no Battery Health section on an iPad running iOS 15.6.
- iPhone Battery and Performance from Apple. Published May 18, 2023. No updates since.
- Check the iPhone battery health and usage from Apple. For iOS 15, 16 and 17.
- January 2022: The battery health information Apple provides in the iOS settings ( Settings -> Battery -> Battery Health or maybe Battery Health and Charging) is meaningless according to Adrian Kingsley-Hughes of ZDNet: Confirmed: Your iPhone is lying to you.
- November 2019: iOS 13.2 tips: Bad iPhone battery life? Here's how to diagnose and fix battery drain issues by Adrian Kingsley-Hughes
- AlDente is a menu bar tool that can limit the maximum charging percentage
(Alternate link). It requires MacOS 11 Big Sur or later. There is a free version.
As of Nov 2023, the paid version is $22.
- coconutBattery from Coconut-Flavour shows the battery capacity percentage (current max charge vs. out-of-the-box max charge), the number of charge cycles and the battery temperature. And more: it shows a history of the state of your battery. There is a free version and a $13 Plus version.
- Battery Health from FlipLab is available both in the Mac App Store and
on their website. The version in the Mac App Store was last updated in September 2018. It requires macOS 10.7 or later and is free, but there is a Power History feature that they charge for. It shows battery capacity, power usage and the charge cycles. The website version is newer, it requires OS X 10.10 or later. It costs $10 and shows charge capacity (which is calls Health), battery temperature and the cycle count. The energy hogs feature allows you to prolong battery life by closing
down apps that are detected as consistently using a high amount of energy.
- 4 Ways to Limit MacBook Charge to 80% for Battery Health
by Ritik Singh. Last update Nov 3, 2023. Originally written Jan 2022. The article has detailed step by step instructions, with pictures, for installing AlDente,
BatteryStatusShow and Charge Limiter. BatteryStatusShow comes in a portable version which does not have to be installed. Charge Limiter is open-source.
Also mentioned are OS features: macOS 10.15 Catalina introduced Battery Health Management that throttles the charging to reduce the premature wear of the
battery. macOS 11 Big Sur added "Optimized Battery Charging," which tries to keep the battery at 80%. The same feature exists in
macOS 12 Monterey.
- According to the article above by Ritik Singh, you can check the battery condition and cycle count on a MacBook using the System Report in macOS: click the Apple icon in the menu bar -> About this Mac -> System Report -> Power and check the Battery Health column.
- If battery charging is paused or on hold on your Mac from Apple. November 8, 2023.
Applies to macOS Big Sur and later. The Optimized Battery Charging feature id designed to improve the lifespan of the battery by reducing the time the laptop spends fully charged.
It delays charging past 80% in certain situations. As with other devices on this page, the computer learns your charging routine and aims to ensure that the Mac is fully charged when unplugged. There are instructions for turning the feature off.
- Feb 13, 2020: Apple says its MacBooks retain 80% of their charge capacity after 1000 charge cycles. That has been the case with most models since 2009. From
How to test a MacBook battery: see if it needs replacing & replace it by Karen Haslam for Macworld.
- April 20, 2023: "Apple does provide a warranty for laptop batteries that's fairly generous: if your battery drops below the ability to retain an 80 percent charge within its first year (or within three years with AppleCare+), Apple replaces it for free. Outside of that period, the cost in the U.S. appears to be a flat $159 for MacBook Air models and $249 for MacBook Pro models." The quote is from here: Should you replace your MacBook battery or pay Apple to do it? by Glenn Fleishman for Macworld. The answer very much depends on the age of the computer. The batteries are easier to replace on older MacBooks.
- Feb 13, 2020: How to test a MacBook battery: see if it needs replacing & replace it by Karen Haslam for Macworld. Press the Alt/Option key -> click the battery charge icon at the top right of the desktop near the clock. The battery can be in 1 of 4 states: Normal (all good) , Replace Soon (this is a mere warning rather than a demand) Replace Now (bad) and Service Battery (bad).
- For Mac laptops with Intel CPUs, there is a battery feature in the OS.
See About battery health management in Mac notebooks from Apple. Published: January 24, 2023.
- To show the percentage of battery charge in the menu bar
Apple menu -> System Settings -> Control Center in the sidebar-> Battery -> Show Percentage
From the macOS User Guide: Monitor your Mac laptop's battery
which has customized content for many different macOS releases.
- FYI: November 13, 2023. How to fix a MacBook that won't charge by Karen Haslam of Macworld. Long article that touches many bases.
- FYI: System Settings -> Battery and Check -> see the advice about Battery Health
- FYI: August 16, 2021: How to check the keyboard, mouse, and trackpad battery level in macOS by Glenn Fleishman for Macworld. Apple does not display the charge of Wirelessly connected peripherals in an obvious place. Some suggestions from the article
macOS Catalina or later: Control Center -> Bluetooth
Any version of macOS: Open the Bluetooth preference pane
Open the Keyboard, Mouse, or Trackpad preference panes
- Maximizing Battery Life and Lifespan from Apple has sections for all their hardware devices. But,
it is not dated, so no way to know how old it is.
- EH: Check the condition of your Mac laptop's battery
from the Apple macOS User Guide. All this results in is either that the battery is functioning normally or that it needs servicing. No other information.
To see it in Sonoma 14: Apple menu -> System Settings -> Battery in the sidebar
- The information here was verified on ChromeOS version 118 in November 2023
- There is a pre-installed Diagnostics app that you can run by clicking on the Launcher button (bottom left corner) and searching for "diagnostics". The left side vertical colum has three sections, but the default section, System, is what we want. This shows the battery health, as a percentage, and the Cycle count.
- More details are available from the command line. Hit Hit Ctrl + Alt + T on the keyboard to open crosh, the terminal app. Then type
battery_firmware info (underscore between battery and firmware, space between firmware and info)
to see the battery manufacturer, the serial number, the design capacity in mAh, the last full charge in mAh (this can verify the percentage from the Diagnostics app),
and the battery Cycle count.
- I read that an "adaptive charging" feature is in the works, but it does not yet exist.
HELP THE CURRENT CHARGE LAST ALL DAY
Dim the display and use a dark background
iOS: Settings -> Display & Brightness -> use the slider bar
Android 14 Pixel: swipe down twice from the top of the screen, move slider left/right
Android 14 Pixel: Settings -> Display -> set a Brightness Level and turn off Adaptive brightness
Turn off Wi-Fi and 4G/5G and BlueTooth and turn them on, only when needed. Ditto for Location/GPS.
Put a cellphone in low power mode
- iPhone: Settings -> Battery -> Low Power Mode (not available on iPads)
I have read that Low Power Mode will automatically kick in when the battery
falls below 20%. Manually turning it on only works if the battery is below 80%, above 80% Apple knows what is best for you and they
will ignore your wishes. From Apple: Use Low Power Mode to save battery life on your iPhone or iPad
Published September 26, 2023
- Android: maybe swipe down from the top and look for Battery Saver
Maybe Settings -> Battery
Maybe Settings -> Battery and Device Care -> Battery -> Power Saving mode
Limit the activity that apps can perform when they are running in the background.
- iPhone: Settings -> General -> Background App Refresh
Choose which apps get to refresh periodically on their own and which ones get updates only when you are actively using them.
- Samsung Android: Settings -> Battery and Device Care -> Battery -> Background Usage Limits
- Pixel Android 14: Turn on the Battery Saver feature. It both sets a dark background and blocks background usage.
Other iPhone settings to minimize the use of the battery
- Stop Siri from listening for your command: Settings -> Siri & Search -> turn Listen for "Hey Siri" off
- Turn off AirDrop: Settings -> General -> AirDrop -> Receiving Off
- There are two screen brighness options and they arm wrestle with each other. To insure that you get the brightness you want, turn off the auto-brightness option
Settings -> Accessibility -> Display & Text Size -> disable Auto-Brightness
- The iPhone 14 and 15 have an Always-On display option. Turn that off
Settings -> Display & Brightness -> disable Always On
- Turn off Location: Settings -> Privacy - >Location service
- Turn off Find My: Settings -> Your Name -> Find My -> Find My iPhone -> disable it
- And FYI: Don't turn off ProMotion to save iPhone 15 Pro battery life by Ben Lovejo
for 9to5Mac. November 16, 2023
Pro Tip: A portable power bank can double your Chromebook usage on the go by Kevin C. Tofel (January 28, 2023). What to look for in terms of both battery capacity (milliamp hours o mAh) and amperage (speed of charging).
This June 2023 article by Robby Payne of Chrome Unboxed, The Chromebook Battery Saver is taking shape to allow better battery life on the go is about a soon to be released Battery Saver feature.
macOS LAST ALL DAY
- Battery Health from FlipLab is $10 on their website. It has an energy hogs feature allows you to prolong battery life by closing down apps that are detected as consistently using a high amount of energy.
- How to save MacBook battery life by Karen Haslam for Macworld. February 2020. Some topics: How long is a Mac battery supposed to last?, Find out what’s using up your battery, Change Energy Saver Preferences, Use dark mode, Stop background activity and Turn off power hogging features.
- Apple introduced a feature in OS X 10.9 Mavericks - the ability to see what apps are using up your battery. In 10.9 or later, open Activity Monitor (Applications/Utilities) -> go to the Energy tab and sort by "Energy Impact" to see the biggest users of the batter power. Activity Monitor can also reveal CPU hogs -> on the CPU tab -> All Processes -> sort by CPU usage.
- Maximizing Battery Life and Lifespan from Apple has sections for all their hardware devices. But,
it is not dated, so no way to know how old it is.
WINDOWS LAST ALL DAY
- Windows 10 Settings -> System -> Battery. Configure Battery Saver as desired. Also check the Battery usage per app section to see the software using the most battery power.
- Personally, I am a huge fan of Process Explorer, a free program from Microsoft. It has no battery related functions, but it does show CPU usage and lets you easily find the software using the most CPU horsepower now, or in the recent past.
Lithium-ion batteries swell in size when things have gone very wrong internally. A swollen battery is dangerous. Do not charge a device with a swollen battery. If the device is running, turn it off. The battery must be replaced and carefully recycled. Until you do, keeping it cool lessons the chance of a fire. In case it does catch on fire, keep it on non-flammable material.
Maybe contact the hardware manufacture for specific instructions.
Lenovo has a Battery Q & A. Published Aug 22, 2019. Last updated: 11/1/2023. Is this Nov 1, 2023 or
Jan 11, 2023?? No way to know.