T100 starting problems. Help!

been trying to start my 05 bonne and it just won't do it. I've had it on an trickle charge but it still won't kick into life. I got a little bang and pop but that's it. Then today I was trying for about 45 mins and it would not do it as per, but when I let go of the start button it just kept ticking over. Hit the kill switch and still did it. Turned it off and took key out and it still keep going. Trying to start. It only stop when the battery finally died! Anyone have any ideas. I'm a noob and have no clue. Any help would be appreciated