Acer 5315 Battery cHarging Problems

Why not try to replace the battery ?
My rechargeable laptop battery often replaced once a year.
I often buy batteries in all-battery.co.uk of discount-battery.org.

All rechargeable batteries have a limited life, and as they age their charge capacity reduces over time and you get shorter and shorter time between charges.
Recharage batteries have a finite number of charge and discharge cycles and batteries over 2 years old are considered nearly worn out. Worn out batteries won't charge up at all.