Definition of Laptop Batteries WHr

When you're comparing laptop batteries, you need a practical way to contrast them side by side. How long a battery can produce a watt's worth of power is a good way to measure the amount of charge it holds. If your battery can produce one watt of power for 12 hours, then its rating is 12 WHr. Therefore, since your laptop batteries provides a fixed voltage to your computer, measuring charge in watt-hours or amp-hours are equally valid methods. For example, if your battery lasts for 20 watt-hours and always provides 10 volts, then it is valid to state your battery's energy storage capacity as 2 amp-hours.