Checking the battery health of a Chromebook isn’t just useful for a device you’ve had for a while. It’s also handy — a must, even, IMO — before buying a used Chromebook. And it’s actually quite easy to do if you know where to look for the information.
First is the battery health indicator, which is a command you run in a crosh terminal. To do this, press ctrl + alt + t on your keyboard, which opens up crosh. Then type battery_test to see the health data: Essentially health of 100% indicates that the battery can accept the full charge of the battery capacity. As time goes on, this figure will slowly degrade. Looks like my Pixelbook battery is still capable of a full charge.
This command also runs a five minute battery discharge test. Note that you can specify the test to run in seconds by typing that number after the command. If you don’t, it will run for 300 seconds.
The second data point I’d look for is the total number of battery cycles, the Chromebook has executed. A cycle is a full charge and you can expect anywhere from roughly 300 to 500 cycles on a typical battery. To find this out, stay in the crosh terminal and type battery_firmware info. * You’ll see various bits of info here, including the battery cycle count. My Pixelbook has gone through 76 cycles, as shown:
If you’re buying a used Chromebook, consider asking the seller to run these commands on the device and show you the results. Once the battery cycle count gets over 200 or 250, I’d be leery of the purchase unless you plan to use the Chromebook plugged in more often than not.
And as far as the battery health, just understand that the percentage is what the device will get on a charge as compared to the same device brand new. So if a Chromebook battery is showing 80 percent health and generally gets 10 hours of battery life as a new unit, you should expect around 8 hours of run time on a single charge at that point.
*Note: If your device doesn’t support the battery_firmware info command, an alternative is to type chrome://system in your browser and look for the power_supply_sysfs field; expand it to see the battery cycle count and additional information.
Alternatively, you can use the Diagnostics app on your Chromebook to get more battery information.
46 Comments
battery_health(??) should this be battery_test?
battery_firmware info not available on an Asus flip.
Good article though for newbies!
You, sir, are correct! I was having a Twitter convo with someone about battery health and got that stuck in my mind. 😉 I corrected to battery_test and also added a note on how to find the battery cycle count for devices that don’t support the battery_firmware info command. Cheers!
So I thought the used chromebook (Acer c720) i bought two days ago had a battery draining fast on internet use. Found your site. Ran the tests indicated. Shows 100% health and 4, yes 4, cycles.
So I apparently bought well. I was spoiled by previous, newer, model I had stolen. It went for a minimum if 7 hours on high use.
Thanks for having this information available for us.
Kevin we have a lot of customers that sell us Asus c302 units that have non charging batteries. I think they have been sitting on a shelf for months and the electrons have depleted into the “thin air”. The batteries will not charge. But linux says that the batteries are at 100% but they I believe have no charge in them BUT because some chip thinks they are at 100% they will not charge…
I have the Asus Flip (C302) and battery_firmware info does indeed work.
Interesting stuff! My Pixelbook shows a cycle count of 319. I got it in the first shipment last Fall and have used it every single day since. BUT, I always keep it plugged in. Now you have me worried.
Don’t panic! 🙂 It’s likely more important to see what the battery health is because that’s an accurate indicator of how much charge the battery can retain.
Whew. Thank you!! My Pixelbook is showing a 101% heath so no worries here. (Also I tested an ancient HP chromebook that I hang onto because it has LTE and one of those T-mobile Data For Life sims. It has a 97% health so, yeah!) Thank you for this and all your good tips, tricks and info.
Well then I guess it isn’t good that my Chromebook says “No battery found” when I run the test… Maybe that’s why I have to keep it plugged in to work…
I bought a used/refurb Acer R11 a few months back. Battery test shows I have 89% capacity but a cycle count of 18. Could this mean the battery was replaced at some point and maybe not with the highest of quality? I see roughly 8-10 hours so I am not complaining, just wondering.
Also noticed the power wash count under the chrome://system is 4. 1 of those was mine, they had this on the dev channel when I got it and I reset it to the stable.
I’m a bit surprised that the capacity is down 11% with so few cycles. Could be a refurbed battery but no idea. If it were my device, I’d run it all the way down to an empty battery and fully recharge; 3 or cycles like that. May not do anything as battery “memory” is generally a thing of the past but it wouldn’t hurt. ?
HI, I used the power_supply_sysfs–option but the count is displayed as 0 on my Acer CB5-571 Chromebook 15 (2015).
Thank you for the information, it was very helpful. However, I’ve inherited some Dell Chromebooks (11 3189 regular model P26T manufacturing year 2017) that will not charge. I’ve run the battery test on them and two indicate they don’t have a battery (of course they do) with the remaining four showing some status of battery health ranging from 99.18% to 98.2%. According to the battery firmware info they have run approximately 14-16 cycles. There is a flag line that states “0x1b AC_PRESENT BATT_PRESENT CHARGING LEVEL_CRITICAL” For the two that don’t sense the battery is a battery replacement the only solution? (Is it even a solution or is there something else wrong?) For the other four what can I try to get them back in the land of the living? Additional info: all will work when plugged in and all had been in storage for about a year with no use or maintenance. Thank you.
my pixelbook shows:
1:battery health:99.63%
2:battery discharged 0.73%in 300 second
3: design capacity:5407 mah
4: last full charge:5387 mah
5: cycle count:1
6: remaining capacity:3726 mah
and I just bought the pixelbook last week and only used a couple hours, i want to know if the battery of my pixelbook is normal?thanks a lot!
Thanks for this helpful article. I have a two year old heavily used Asus 302 and have recently begun to notice a shorter on battery times than I’d come to expect. These tests tend to confirm that impression. My machine shows a battery health of 82% and the cycle count of 225. It will be interesting to see how well it holds up at this late stage of its life. The shortened time between charges is beginning to cramp my style.. I’ve been looking at possible replacements, but so far, nothing has excited me enough to commit to another long term relationship. Perhaps the C434 will catch my attention.
The Asus C302 is known to ship with only about 93% battery health, so yours probably didn’t start at 100% when it was new. If you’re getting less battery life, it might be because of your extensions.
The Asus C302 is known to ship with only about 93% battery health, so yours probably didn’t start at 100% when it was new. If you’re getting less battery life, it might be because of your extensions.
Battery count is 411, Battery health is 85.35, yet the battery don’t go beyond 4 hours on my hp chromebook 14. What can I do?
my battery cycle count is 638 on an older chromebook
battery health >approx 70 %
what does that mean?? I have a new chromebook but do not want to import what i no longer need to waste space?
does the Chromebook have a changeable battery or do you just chunk it
Interesting article. My Asus C101 is only 3 months old, but my health is already down to 90%. As it’s still in warranty, should I get it replaced? I think it started new at around 95%…but to lose 5% in 3 months seems excessive. Is this crosh command reliable as an indicator?
My Samsung chromebook is a couple of years old…use it mostly plugged in. Did the tests above, and this is what I got:
No test length specified. Defaulting to 300 seconds.
Battery is discharging (97.08% left)
Battery health: 33.58%
Please wait…
Battery discharged 3.64% in 300 second(s).
I guess the battery is probably dying…when I do use it on battery, it will go a couple of hours at the most.
Are the batteries replaceable? And..is it worth it? Everything else seems to be fine, tho a bit slow on occasion.
There’s no easy way to replace the battery, although I’m sure it can be done if you can get a new battery and don’t mind risking breakage when opening the Chromebook. I wouldn’t advise it though.
THANK YOU BRO’S! Man, I could not believe my amazon battery had so many cycles! I use my CHROMEBOOK a LOT! Course I use it in my car as a hub of my car computer. I had to use it the other day in Family court, and it just died with a full battery. This really helped out. My Old OEM battery was starting to get Puffy and bending my ASUS Chromebook Flip 202 (The O.G. Chromebook!) .
I’m going to swap this pack out again soon. The last one lasted for YEARS. This one made it less then a year. Oh well. I wonder if it was covered under amazon Prime’s warranty.
Here is my stats on my battery:
crosh> battery_firmware info
Battery info:
OEM name:
Model number: C100-80
Chemistry :
Serial number: BAD0BAD
Design capacity: 7820 mAh
Last full charge: 3408 mAh
Design output voltage 3850 mV
Cycle count 569
Present voltage 4010 mV
Present current 3311 mA
Remaining capacity 1360 mAh
Flags 0x09 AC_PRESENT CHARGING
crosh> battery_health
ERROR: unknown command: battery_health
crosh> battery_health
ERROR: unknown command: battery_health
crosh> battery_test
No test length specified. Defaulting to 300 seconds.
Battery is charging or full (80.11% left)
Battery health: 43.61%
Please make sure the power supply is unplugged and retry the test.
crosh>
Yup, I’m Lucky that ChromeOS and Chrome by itself saves all the data even if your laptop is Unplugged all of a sudden. (Whew!)
So yea, even at 80% the thing dies. Notice the “BAD0BAD” ?
I wonder if that’s not a Typo. Would make sense. ?
My battery isn’t too horrible given i know i’m hard on it but my c213sa is not in the greatest possible shape in terms of battery. probably will replace the battery once it gets to 75% health
Battery health: 86.75%
OEM name: AS1FOAD
Model number: C213-60
Chemistry : OOC0
Serial number: 10FA
Design capacity: 6044 mAh
Last full charge: 5240 mAh
Design output voltage 7700 mV
Cycle count 201
Present voltage 7626 mV
Present current 497 mA
Remaining capacity 2246 mAh
Flags 0x06 BATT_PRESENT DISCHARGING
Same model here 🙂 Here’s my readout:
crosh> battery_firmware info
Battery info:
OEM name: AS1FOAD
Model number: C213-60
Chemistry : OOC0
Serial number: 014D
Design capacity: 6044 mAh
Last full charge: 5204 mAh
Design output voltage 7700 mV
Cycle count 87
Present voltage 7710 mV
Present current 605 mA
Remaining capacity 2888 mAh
Flags 0x06 BATT_PRESENT DISCHARGING
Notice I have much fewer cycles than you, but my battery health is practically the same. This leads me to believe:
1) The readings from these battery tests are a crock…
or
2) Asus skip on their batteries and use shoddy ones.
However, the beauty of our model is that it’s almost modular. It’s easy to buy and fit a replacement battery yourself. Plenty of places sell replacement c213 batteries, and I think there’s a YT video or tutorial out there on how to fit the replacement. When I get to the point where I find battery life is causing me grief, I’m sure going to give it a go. I love my little c213.
Hello.
I’ve just tested my battery health and it’s says:
Battery test 97,59%, battery discharged 0,59% în 300 seconds. My chromebook is a Lenovo S340-14.
Is this a problem with my battery health? Thank you.
Looks like my post got deleted. So will post it again.I have had same or similar problems to above users.
a) My Acer Chromebook is reluctant to start on battery in mornings after shut down previous day,requires charger to be plugged in for a few mins even though battery is charged.
b) When it does come on sometimes the battery indicator does not show, and other times it does show but with only a small % of charge left despite being fully charged according to indicator (and blue LED is on)
c) On occasions when battery indicator does not show the laptop will go all day before battery gives out
d) Crosh rest give various battery condition ranging from 98% with 8% battery health to other times around 100% battery condition.
So it does not look like battery is worn out, looks to be a memory problem with battery charging circuit, or software issue. I have seen on other forums that Google OS has a bug that causes this. It seems strange that so many people have the same issues. My computor is only 1 year old, it was supplied by Currys PC World, but the engineers there had no idea what the problem was, in fact they were useless and obviously had not had product training on the Acer 15 Chromebook.
Finally a way around the problem is to leave laptop on sleep mode and not shut it down overnight. It will start immediately during daytime if I do shut it down for any reason, ie to take in a Google update.
Hey John, I’m finally back online after a week or so of illness. I did a search for any battery/bootup issues with the Acer Chromebook 15 in the official Google bug lists but came up empty. While I don’t have any answers to solve the problem, I do have two suggestions. First, if you haven’t already, consider doing a Powerwash on the Chromebook to see if a clean restore of the operating system fixes the problem. Second, I’d file a bug so that the Chromium engineers at Google can look into this. It’s easy to file a bug: Just hit Alt+Shift+I on your Chromebook and provide as many details as you can. Once the bug is filed and assigned a bug number, you can look for it / view progress here: https://bugs.chromium.org/p/chromium/issues/list Wish I could offer more of a solution.
Sorry, in a bit of a rush so haven’t had time to check if you’ve tried the below already. If not, give this a try. What have you got to lose?
The following steps will disconnect and reconnect the battery on your device. The following steps will reset the battery connection on your Chromebook:
Plug in the charger to either port.
Using one hand, press and hold Refresh+Power keys for 5 seconds.
While continuing to hold those keys, unplug the charger.
Release Refresh+Power keys.
Wait 10 seconds.
Plug in the charger (if device doesn’t start, press Power).
This can sometimes take up to 5 times to fully reset the connection. If the Chromebook is still not charging after this, then please reply to this email and let me know.
Ben – Have done the done a refresh + power several times and get indication 100% charge and 0.07 left, battery full charged with blue indicator light on. CROSH test gives 98.73 with 1.26 battery health
Kevin – Alt+Shift+I does nothing (does not connect to Google) I dont want to do a power wash as I will loose some data
So looks like there is possibly a fault with battery, may buy a new one, but as I can run with charger plugged in its not an issue unless I need to run on battery away from mains supply.
just for reference
Device: Samsung Chromebook Pro
@20200603
crosh> battery_test
No test length specified. Defaulting to 300 seconds.
Battery is discharging (43.61% left)
Battery health: 88.13%
Please wait…
Battery discharged 0.97% in 300 second(s).
Device: Samsung Chromebook Pro
@20200811
crosh> battery_test
No test length specified. Defaulting to 300 seconds.
Battery is discharging (74.26% left)
Battery health: 89.11%
Please wait…
Battery discharged 1.37% in 300 second(s).
crosh> battery_firmware info
Battery info:
OEM name: SDI
Model number: 4352D51
Chemistry : LION
Serial number: 0739
Design capacity: 5140 mAh
Last full charge: 4577 mAh
Design output voltage 7600 mV
Cycle count 873
Present voltage 7816 mV
Present current 528 mA
Remaining capacity 3329 mAh
Flags 0x06 BATT_PRESENT DISCHARGING
My chromebook, which is about 4 years old, is currently at 45% battery health. Does that mean it doesn’t have much life left?
My Lenovo C330 will not run on battery power at all. It is a new battery and is full charged. When I do the battery_firmware command it comes up recognizing info but will not do the check or update. Is this a software issue? The unit runs perfect on adapter power.
I would consider doing a Powerwash to factory reset the Chromebook. That might help if this is a software/firmware problem. If not, I’d reach out to Lenovo for hardware support.
I have a Levono 81MC Chromebook.
My cycle count is 115. Will this affect how good my Chromebook reacts to something given I’m used the chromebook for around 5 months?
> Will this affect how good my Chromebook reacts to something
I kind of understand what you’re asking here, and if so, no, the ‘health’ of a battery does not affect the direct performance of a computer. The battery is the part of the laptop that supplies the computer the power it needs in order to run for as long as the battery has charge. As long as the battery supplies the computer with sufficient power, the laptop will run and react as well as it’s able to (‘as well as it’s able to’ depends on many factors: hardware components such as the processor, the memory, and how efficient the operating system is).
However, the older and more used a battery gets, the less charge it holds. This means as a battery gets older, it will run the computer for progressively less time between being charged.
Ultimately, batteries wear out (just like us humans) and there’s nothing you can do about it except replace the battery for a new one, or just run the computer with it permanently plugged into mains electricity.
oh thanks!
Hello here is mine. Time for a new battery?
crosh> battery_firmware info
EC result 3 (INVALID_PARAM)
Battery info:
OEM name: LG A50
Model number: A50
Chemistry : LiP
Serial number: 560A
Design capacity: 5407 mAh
Last full charge: 732 mAh
Design output voltage 7700 mV
Cycle count 1312
Present voltage 8754 mV
Present current 311 mA
Remaining capacity 506 mAh
Flags 0x0b AC_PRESENT BATT_PRESENT CHARGING
and this….
crosh> battery_test
No test length specified. Defaulting to 300 seconds.
2022-05-29T10:52:58.090483Z ERROR dump_power_status: [power_supply.cc(745)] Failed to open /dev/cros_ec: Permission de
nied (13)
2022-05-29T10:52:58.090552Z WARNING dump_power_status: [power_supply.cc(640)] Setting full factor in OS is deprecated.
2022-05-29T10:52:58.101250Z ERROR dump_power_status: [power_supply.cc(745)] Failed to open /dev/cros_ec: Permission de
nied (13)
2022-05-29T10:52:58.101340Z WARNING dump_power_status: [power_supply.cc(640)] Setting full factor in OS is deprecated.
2022-05-29T10:52:58.133633Z ERROR dump_power_status: [power_supply.cc(745)] Failed to open /dev/cros_ec: Permission de
nied (13)
2022-05-29T10:52:58.133713Z WARNING dump_power_status: [power_supply.cc(640)] Setting full factor in OS is deprecated.
2022-05-29T10:52:58.147710Z ERROR dump_power_status: [power_supply.cc(745)] Failed to open /dev/cros_ec: Permission de
nied (13)
2022-05-29T10:52:58.147787Z WARNING dump_power_status: [power_supply.cc(640)] Setting full factor in OS is deprecated.
2022-05-29T10:52:58.159150Z ERROR dump_power_status: [power_supply.cc(745)] Failed to open /dev/cros_ec: Permission de
nied (13)
2022-05-29T10:52:58.159355Z WARNING dump_power_status: [power_supply.cc(640)] Setting full factor in OS is deprecated.
Battery is discharging (69.81% left)
Battery health: 13.49%
Please wait…
2022-05-29T10:57:58.204846Z ERROR dump_power_status: [power_supply.cc(745)] Failed to open /dev/cros_ec: Permission de
nied (13)
2022-05-29T10:57:58.205066Z WARNING dump_power_status: [power_supply.cc(640)] Setting full factor in OS is deprecated.
Battery discharged 10.52% in 300 second(s).
Pixelbook 2017
Unfortunately, I’d say yes. Just based on the battery discharge test, I’m guessing you see between 45 and 60 minutes of run time on a charge now?
Not surprising after all those cycle counts! Surprised the thing hadn’t collapsed altogether.
Tell you what my friend. If you can find somewhere to both get a new Pixelbook battery, and someone brave enough to try and fit it, then let us know! We all want to know ?.
hi Kevin and everyone paying attention to this. thank you for response. I think a new battery would be good although I have got used to keeping my device power into the AC
sorry about how that looked I used copy paste when I should have sent screenshot.
hi Rod there is this…
https://www.ifixit.com/Guide/Google+Pixelbook+Battery+(Back+Panel)+Replacement/103036
Hi Greg.
The very best of luck to you sir!
Back when I owned a PB, (first few years) there were no official Google spare parts, nor was anyone able to repair or replace things. I hope for you that’s changed.
If there are still no official Google batteries available, hopefully you’ll be able to russle one up on eBay or the like that’s been pulled from a ‘parts or repair’ newer machine.
Let us know how you get on please!
Dont know how old my acer flagship chromebook is but I got it refurbished/renewed 3 years ago and been having a lot of problems with it lately. It just crashed again right now after just rebooting it 5 mins ago. I had 10 tabs open. After having 5 or 6 tablets 3 phones and now a tablet I know the signs of a dying battery. Been having to charge a lot more lately to where I have to keep it plugged in more than I dont. Whole processing system crashes all the time everyday especially with more than 3 or 4 tabs open. My diagnostics shows
Battery life
84%
Cycle count
1146
Current
1609mA
My friend, it suppose it could be a dying battery. But 84% health is not really the sort of level where you’d experience the problems you are having.
Do you have the same problem when the Chromebook is plugged into mains power?
Do you have similar problems when logged onto the Chromebook as ‘guest’ (i.e no extensions etc).
Have you tried a power wash?
Have you tried a system and/or battery reset?
Have you reloaded the OS from a self-made recovery flash drive?
These are all things you could try to see if they make any difference. Might be worth a try if you’re at the end of your tether…