Patent ID: 7656125

Claim:
A method of controlling a storage voltage of a battery pack with control electronics for an electronic device, comprising the steps of: a) sensing a storage voltage of the battery pack wherein the battery pack includes at least one lithium-ion cell having a cathode that includes an active cathode mixture, wherein the cathode mixture includes a manganate spinel represented by an empirical formula of Li (1+x1) (Mn 1−y1 A′ y2 ) 2−x2 O z1 where: x1 and x2 each independently are equal to or greater than 0.01 and equal to or less than 0.3; y1 and y2 each independently are equal to or greater than 0.0 and equal to or less than 0.3; z1 is equal to or greater than 3.9 and equal to or less than 4.1; and A′ is at least one member of the group consisting of magnesium, aluminum, cobalt, nickel and chromium; b) sensing a time period for which the electronic device is not interacting with a user; c) determining: i) if the time period is longer than a predetermined time value, ii) whether the storage voltage is within a predetermined range of voltage at any time during that time period, and iii) whether the storage voltage is at or above a predetermined voltage at any time during that time period; and d) triggering a discharge mechanism if, i) the time period is longer than the predetermined time value, and the storage voltage is within the predetermined range of voltage at any time during that time period, to thereby adjust the storage voltage of the battery pack to below the predetermined range of voltage; or ii) the time period is longer than the predetermined time value, and the storage voltage is at or above the predetermined voltage at any time during that time period, to thereby adjust the storage voltage of the battery pack to below the predetermined voltage.