Four main factors determine your EV battery charging speed:
The battery’s state of charge. The less energized a battery is, the faster it typically charges.
The battery’s temperature. Your EV has technology that regulates charging based on the battery’s temperature and the surrounding ambient temperature. Colder temperatures generally mean slower charging.
Other loads on the battery charger circuit. The more kilowatts drawn on the charging station circuit, the slower the charging speed will be.
Battery deterioration. Batteries lose capacity over time. The more your battery’s capacity deteriorates, the longer it will take to charge.