If your project is moving a lot of power around, and efficiency is key, an Adafruit LM73100 Ideal Diode breakout is a great way to keep your power budget tidy! As long as your power supply is 3~23V DC and up to 5A, use this in place of a diode to keep current flowing one direction. However, unlike a diode, you won't suffer a 1V+ forward drop which just gets lost as heat. Instead, the internal chip has two back-to-back FETs, with a typical Rdson of 30 mΩ. That means that even with 5A, you'll lose around 150mV. This makes it perfect for efficiency-sensitive setups like solar panels and LiPoly batteries.