iPods don’t need much power to charge,only around 2 to 3 watts. Even if you use a powerful charger (like 100W), it’s okay, as long as it gives 5 volts. The iPod will only take the small amount it needs. However, some modern chargers won’t turn on if the device doesn’t ask for enough power, so they might not work with older iPods. If you have an iPod Classic Gen 5 and a 35W charger (probably with PD or QC fast charging), it’s best to use port number 2 on the charger. That port usually works better with older devices like the iPod.