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CHAPTER 2: GETTING TO KNOW YOUR LAPTOP
Q: I did not use my spare battery for a few days. Even though it was fully
recharged, there wasn’t as much power left as a newly charged one. Why?
A: e batteries will self-discharge (1% per day for Li-ion) when they are not being
recharged. To ensure a battery is fully charged, recharge before use. Always keep
the battery inside the laptop and have the AC adapter connected whenever
possible.
Q: I did not use my spare battery for months. I am having a problem
recharging it.
A: If you happen to leave your battery to go through an extended period of self-
discharge, say more than three months, the battery voltage level will become too
low. e battery then needs to be pre-charged (to bring the battery voltage level
high enough) before it automatically (for Li-ion only) resumes its normal fast
charge. Pre-charge may take 30 minutes. Fast charge usually takes 2-3 hours.
Power Management

Understanding Power Consumption

In order to fully utilize the power of your battery, it would be a good idea for you
to spend some time acquiring a basic understanding of the power management
concept from your operating system.
You can use the power options in your operating system to congure the power
settings on your computer. e Microsoft® Windows® operating system installed
on your computer provides three default options:
Balanced — Oers full performance when you need it and saves power
during periods of inactivity.
Power Saver — Saves power on your computer by reducing system
performance to maximize the life of the computer and by reducing the
amount of energy consumed by your computer over its lifetime.
High Performance — Provides the highest level of system performance
on your computer by adapting processor speed to your activity and by
maximizing system performance.