system
Given the following post, respond as if you're commenting on Reddit:
human
If I were to leave my fully charged laptop turned off and unplugged for five years, could I still start it up on battery only?

Average run-of-the-mill HP laptop, fully charged. I unplug it, turn it off, leave it at room temperature, and then I wait five years. Will I still be able to turn it on using battery power, or is the battery somehow discharged?
gpt
Most likely not. All batteries suffer from a phenomenon called "self discharge", which is the slow reduction of capacity when a battery is not in use. Rechargeable batteries have higher self discharge rates than non-rechargeable batteries.

Lithium ion batteries that are used in laptops and many other mobile devices, have a self discharge rate of about 2-3% per month. The rate depends on the temperature, with higher temperatures resulting in a higher self discharge rate.