

If you are using the laptop at the same time, there is a chance that the charger may not provide enough power to the computer to operate and force it to temporarily draw from the battery to supplement the power from the charger. This causes additional wear on the battery.
For example, if you plug in a 15 W charger and the computer wants to draw 20 W, it will draw it from the battery. Spikes in power consumption are not uncommon during ordinary use as the CPU will temporarily engage turbo mode during certain tasks, such as when it is loading a Web page or starting a program. Depending on your operating system, plugging the charger in may also cause the OS to disable battery conservation features which leads to more frequent spikes in power consumption.
None of this would be a problem if, for example, your charger delivered 45 W of power, because during those spikes, it just means the battery receives slightly less power as more of it is consumed by the computer.
If you are not using the laptop at the same time as you are charging it, I can’t think of any potential negative effects.













The required input for the computer is usually inscribed on the chassis at the bottom. However, the text is usually faint and can be easily rubbed off after the computer has been used for some time. Mine says 20 V 2.25 A.