Older BIOS versions might misreport battery levels, leading to sudden shutdowns at “20%.” Updating the BIOS can fix battery metering and improve charging logic.
To update the BIOS on your , you must download the official update from the Acer Support page and run it while connected to a stable power source. The latest confirmed version for this model is v1.15 , released to improve system performance. Essential Precautions acer aspire es1-512 bios update