When you recharge something, you bring it back to life or reenergize it. You might charge your cell phone in the morning and then recharge it later in the day.
If you can charge your electronics (or provide them with electrical energy), you can also recharge them when that energy is depleted. In addition to your camera battery and laptop, sometimes you need to recharge yourself, or take a break so you can become energized again. Less commonly, recharge is used to mean "refill a glass," and the original meaning, in the fifteenth century, was "to reload a vessel."