Learn why a laptop battery percentage suddenly drops from 80% to 15% and the laptop shuts down shortly after, as required for the CompTIA A+ Core 1 220-1101 exam. Understand how battery degradation causes rapid charge loss and what steps to take for reliable laptop performance.
Table of Contents
Question
A laptop’s battery percentage suddenly drops from 80% to 15%, and the laptop shuts down shortly after. What is the most likely cause?
A. A misconfigured power plan
B. A failing battery
C. A slow Wi-Fi connection
D. A corrupt boot sector
E. A failing CPU
Answer
B. A failing battery
Explanation
A sudden drop in battery charge typically indicates a degraded or faulty battery.
A sudden drop in battery percentage followed by a rapid shutdown is a classic sign of battery degradation or failure. As lithium-ion batteries age, their internal resistance increases and their ability to hold a charge diminishes. This chemical aging leads to inaccurate charge reporting and abrupt drops in the displayed battery percentage, often from a high value (such as 80%) to a critically low level (like 15% or even lower), after which the laptop shuts down quickly.
Common causes and symptoms include:
- Aged or worn battery cells: Over time, battery cells lose capacity, resulting in unreliable and unpredictable battery readings.
- Sudden voltage drop: The battery’s internal circuitry may misreport the actual charge, causing the system to think there is more power remaining than there actually is, leading to sudden drops and shutdowns.
- End-of-life behavior: Batteries nearing the end of their usable life often exhibit rapid declines in performance, including abrupt power loss and inability to sustain the laptop without AC power.
Resolution:
The most effective solution is to replace the battery with a new, manufacturer-approved unit. Battery calibration or software fixes rarely resolve this issue once the battery has physically degraded. Continuing to use a failing battery can also risk further hardware issues or, in rare cases, swelling and safety hazards.
A failing or degraded battery is the most likely cause of sudden, dramatic drops in battery percentage and rapid shutdowns. Replacing the battery is the recommended course of action for restoring normal laptop operation.
CompTIA A+ Core 1 220-1101 certification exam practice question and answer (Q&A) dump with detail explanation and reference available free, helpful to pass the CompTIA A+ Core 1 220-1101 exam and earn CompTIA A+ Core 1 220-1101 certification.