There are a large number of manufacturers producing laptop computers with a wide range of configurations. The power requirements of a laptop vary, depending upon the design, specifications and configuration of a particular model.
Based on the estimate of maximum power requirements and the available space to install the battery, laptop manufacturers order battery packs suitable for their various models of laptops. Laptop manufacturers normally do not manufacture the batteries themselves but procure them from specialist battery manufacturers.
All modern laptops have lightweight lithium-ion or lithium-polymer batteries, which are usually pre-installed in the laptop. These batteries are powerful enough to run the laptops plus any accessories such as MP3 players, DVD players and USB devices.
With normal use, lithium-ion batteries are expected to last for about three years but it’s important to note that the three-year period starts as soon as the batteries are manufactured and not when they are actually put in use. The indication that the battery needs replacement usually comes when the laptop cannot be operated anymore unless attached to the mains supply through an adopter.
When it is apparent that the battery needs to be replaced, it is advisable to contact the authorized dealer for a particular make of laptop. The authorized dealer will be able to supply the correct replacement battery type and will also install the replacement battery if requested.