My battery wont charge instead the battery gets drained

I recently bought the iphone 5 in November and ever since it has had problems with the battery, As most people have. Recently my battery has gone down quicker and quicker. Now for some reason my battery wont charge at all. when connecting to the charger the phone delays in recognising it and when it is removed it still says its charging. Now when it is charging it does not charge but drain the battery faster. I have tried buying a new charger, using older charges. I have updated the phone and nothing. I dont know what to do.