I know many won`t believe, but i have a HP folio 13 since 2011... When i bought the laptop the battery lasted 3 hours. Now, it last also 3 hours. I`ve been abusing it a lot, leaving it uncharged for months, or using it like a router for almost a year. Now, it`s daily used on battery, and charged in the evening, like a phone.. battery time.. 3 hours... Like new. I really don`t understand that battery. P.S. Software shows 0 wear on battery...