170 Not charging battery

My 170 has a brand new battery I have cut 3 different yards it has Ben clicking like it has a bad connection somewhere today I turned the blades off then when I went to turn them back on they wouldn't turn on I turned the mower off trying to find out why they would not work when I got on it it wouldn't even click I tested the battery 11 volts jumped it off I did not even click so how can I fix this the alternator and starter are together should I have to take the alternator apart