It Appears You Can Extend Your Li-ion Laptop Battery Life By Charging It To Only 40%-60% of It's Capacity

Before I tell you what this is about, please note that the source is marked as "unreliable?" on Wikipedia so it may or may not be true.

I recently came across an idea on Ubuntu Brainstorm about preserving laptops battery life that leads to an Wikipedia article which states that a Li-ion battery can have a much longer life if charged to only 40%-60% of it's capacity, and not to 100% like most laptop batteries are charged:

At a 100% charge level, a typical Li-ion laptop battery that is full most of the time at 25 °C or 77 °F will irreversibly lose approximately 20% capacity per year. However, a battery in a poorly ventilated laptop may be subject to a prolonged exposure to much higher temperatures, which will significantly shorten its life. Different storage temperatures produce different loss results: 6% loss at 0 °C (32 °F), 20% at 25 °C (77 °F), and 35% at 40 °C (104 °F). When stored at 40%–60% charge level, the capacity loss is reduced to 2%, 4%, 15% at 0, 25 and 40 degrees Celsius respectively.

Read more about this, on Wikipedia and BatteryUniversity.com