Is it expected for the battery capacity to fall by half with little usage? Nitro 5 (AN515-31)

atonement
atonement Member Posts: 57 Devotee WiFi Icon
edited July 2021 in Nitro Gaming
My Acer Nitro 5 (AN515-31) just passed the 3 year mark. It's been used plugged pretty much all the time. Only time the battery gets any use is in case of a rare power cut. Temps. aren't an issue as even while gaming battery temps. rarely cross the early thirties, mostly in the mid-twenties. Battery life was good (7-8hrs,low brightness, undervolted, Turbo Boost off) for the first 2 years or so but rapidly degraded afterwards. Currently 3-3.5hrs. The battery stops charging randomly, usually in the 80-85% range. The charging light blinks orange constantly. I have tried the pinhole reset to no avail. Does Acer employ poor quality batteries? Or did I get a dud one?
Every manufacturer guarantees 80% battery health over 300 battery cycles. But in my case the battery health is down to 66% despite a pitiful 55 cycles as reported by the official Acer tool. Even that is an overestimate as the battery falls straight to zero from 15-25% causing the laptop to shutdown abruptly.
My previous laptop which ran much hotter didn't need a battery replacement before 4.5-5 years, over 300 battery cycles. Yet here in just 2.5 yrs the battery had degraded so much that it was very noticeable. Suffice to say this will be my last ever Acer. 
Warranty extension was a waste as it doesn't cover the battery. Replacement costs around $70-80 but if it's quality is as poor as the original then I won't bother. 
Please check the attached ss from the Acer battery tool which clearly shows how much the battery has degraded despite little usage. 

Thread was edited to add model name to the title


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