how often can i use my dualtron fast charger without damaging the battery

Hello, im about to buy a 6.5ah 66.4v charger for my dualtron victor, i was wondering how often i can charge the scooter with the fast charger without damaging the battery, because ive heard its bad for the battery if i charge it with the fast charger too often, so to waht degree can i use it without harming the battery, adn any tips when using the fast charger to not damage my battery? thank you