iPhone 15 Pro Max Gets Hot with MagSafe Charger

It is normal. A MagSafe charger supplies twice as much power (15 watts) as a Qi charger (7.5 watts). It will get warmer based on the Second Law of Thermodynamics. Anything that creates or uses energy does so with some loss. That lost energy is expressed as heat. So when you charge the phone it generates heat in the power source, heat in the charger circuit in the phone, and heat as the energy goes into the battery. The faster the charging, the more heat is generated. It won’t hurt the battery; the phone’s charger has a temperature sensor, and will manage the charge rate to keep the battery temperature at a safe level.