My battery will jump from 20%-30% to 6%-10% in a literal blink. I'm not sure how old this laptop is offhand but it's at least 3 to 4 years old. Should I
ACER ASPIRE E5 571 37UB LAPTOP CMOS JUMPER LOCATION TO RESET BIOS — Acer Community
Acer Aspire 5740 DG BIOS Battery - YouTube
Amazon.com: Rome Tech CR2032 CMOS Battery for Acer Spin 5 SP513-52N - Laptop Backup BIOS RTC 3V CR 2032 Battery with 2 Wire Medium Cable Slim Connector (1-Pack) : Electronics
How to update your BIOS on an Acer notebook computer - Acer Community
How to locate and reset Acer 5920G CMOS Battery – without dismantling the whole laptop | iTech Online
tl;dr – Reviving an Acer Aspire 3820 TG with a broken BIOS chip – Lektion des Tages