A system and method for identifying and responding to exceptional charge events of series-connected energy storage elements. An exceptional charge event detector for an energy storage system having a plurality of series-connected battery elements, comprising: a data acquisition system determining, for each battery element of the plurality of series-connected battery elements, a series of charge dependent parameters during an operational period of the energy storage system; a controller, coupled to said data acquisition system, establishing a characterization for each battery element of the plurality of series-connected battery elements from said series of charge dependent parameters; wherein said characterization includes either a normal characteristic pattern or an exceptional characteristic pattern for each time segment of a plurality of time segments spanning said operational period; and wherein said controller detects an exceptional charge event for a selected one battery element whenever said characterization for said selected one battery element includes an exceptional characteristic pattern in any particular time segment where a normal characteristic pattern is expected.