Is it right that your alternator doesnt produce enough charge to keep your battery topped up. the battery dies after a week and a half then I charge it and it lasts for the same period before charging again. whats the problem?
check the charging rate 13.5v to 14.2 v is OK for a good alternator . make sure the fan belt is tight , if these are OK then the battery needs to bee drop tested . and test for a drain. good luck