inputs.text: make kit - received item timereplaced original sick battery one described lot youtube tutorialsfirst surprise phone couldnt boot connected charger ok iphone got back life againsecond surprise around 90 battery power phone suddenly died middle phone conversationthird surprise even fully charged iphone cannot boot logo coming disapears 3040 seconds phone external power necessary power phone anywayforth last surprise 90 bit less phone always diesbeing experienced electronics im electronics engineer decided investigate problem battery assembly demolished liion element put serious loadunload test element shown working properly problem belongs controller small board bottom battery assembly covered tape replaced controller one removed old sick battery say battery works toi dont really think ive lost money tools set cost something anyway liion element workingwhat would recommend case experienced sodering know couple things electronics tryin case youve seen solder hobby shop never tried anything better dont try parts small controller board easy overheated shortcirquited liion element may put real troubles