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Posts: 7
Registered: ‎04-29-2015
Location: arequipa peru
Views: 1,625
Message 1 of 6

Lenovo Y40 Battery Usage

Good day to this awesome community


I recently purchased a notebook 'y40' and  i have doubts about the use of the battery, can i work with the notebook plugged in to the electricity without having to worry about the life span of the battery ?.

Keep in mind that the battery can not be removed .


Retired Support Specialist
Posts: 4,447
Registered: ‎04-22-2013
Location: Philippines
Views: 1,611
Message 2 of 6

Re: Lenovo Y40 Battery Usage

Hi Ebon_Knight,


Welcome to Lenovo Community!


Using the computer with the AC conected is just fine.


 I would say it is OK to use the your laptop while plugged in,

Because once you plugged in an AC adapter, Your computer switches to AC power mode where it gets power from AC charger while charging the battery.


  Now about overcharging , If you have the Lenovo energy Management Software configured to "Optimized battery health" then you should not have to worry. it will prevent charging your battery to a 100% and prevents from over charging, 


If the computer did not came with the software, Lenovo Energy Management  can be downloaded from just choose your computer model and OS version.


Hope this helps


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Paper Tape
Posts: 4
Registered: ‎05-05-2015
Location: United States
Views: 1,585
Message 3 of 6

Re: Lenovo Y40 Battery Usage



I having some serious battery issues with my Y40 in the workplace. I purchased a new Y40 last summer and now the battery is will never last more than 1 hour and reads incorrectly. It will get stuck charging at random levels, sometimes get to 100%, but never last for more than an hour even with no apps running. Sometimes it says 100% for 20 minutes then just dies.


I've updated my drivers and Lenovo Energy Manager but its only getting worse. I have around 150 days left on my warrenty so what are the next steps there? I use this laptop daily for work so I need a solution fast and can't be without my machine or a replacement for a single day. Sending it in is not an option.



What's DOS?
Posts: 3
Registered: ‎08-14-2015
Location: United States
Views: 1,277
Message 4 of 6

Re: Lenovo Y40 Battery Usage

Had the same problems exactly as you described. Did you find a way to fix it?
Paper Tape
Posts: 4
Registered: ‎05-05-2015
Location: United States
Views: 1,271
Message 5 of 6

Re: Lenovo Y40 Battery Usage

No, had to send it in unfortunately. I contacted Lenovo service a couple times (got hung up on once) before someone there remoted onto my machine and verified it was a under warranty hardware issue. Then had to rent my own replacement for a few weeks on my $; I was never really sure how long it would take until the end as they were out of my parts. Best of luck. 

Former Employee
Posts: 1,664
Registered: ‎09-16-2014
Location: US
Views: 295
Message 6 of 6

Re: Lenovo Y40 Battery Usage

In response to customer reports of unexpected battery gauge behavior on Y40-70 and Y40-80 laptops, Lenovo determined the battery gauge software is performing as expected. The unusual gauge results being reported are a reflection of the battery reaching end of life.


Lenovo has released a Service TIP to assist customers with obtaining battery replacements under warranty, or if out of warranty, to find a replacement battery from Lenovo-approved vendors. The Service TIP can be found here:


The part numbers for Y40-70/80 batteries are:

Y40 SP/A L13M4P01 7.4V48Wh 4cell bty (Y40-70/Y40-80) 121500248

Y40 LG L13L4P01 7.4V48Wh 4cell bty (Y40-70/Y40-80) 121500249 substitute part 121500251

Y40 CP/C L13C4P01 7.4V48Wh 4cell bty (Y40-70/Y40-80) 121500259 substitute part 121500251


To determine which battery came with your Y40 notebook, instructions for removing the bottom cover can be found in the Hardware Maintenance Manual pdf here. An alternative to opening your system (which does not void warranty) is to search for batteries using the model/product number located on the bottom cover.


Thank you,

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