Do not know why this battery does the same as my old battery. The quality and the performance of this battery leaves something to be desired. He was new and packaged, but also keeps one grade so from morning to evening. Man indeed wants a battery that lasts a little longer, the one does not need to charge during the day twice. As must give a little more effort well the Chinese industry. Despite the back burner on the phone he did not last longer. Has it something to do with the quality of production. The seller can not for it.