No, pedal batteries are, by design, ignored by the circuitry once the pedal is plugged to grid power. However, if you happen to turn off your power supply at some point, and leave the pedal input and output jacks connected to the rest of your rig, it's likely that it would start draining energy from the battery. This is because. Power supplies can't recharge the batteries on your pedals. At least traditionally that's not how they work. In fact, power supplies don't interact with your pedal's batteries at. There are many reasons to remove batteries from a plugged-in pedal, but probably the main one is why are you using batteries anyway?. To conclude on this topic, I think I made my opinion rather clear, but I will state it one more time: There's no point in powering your pedals with batteries unless you have a good excuse.
Guitar pedals can be powered using batteries, an AC adapter, or a DC power supply (power brick). A battery is fine for an individual pedal, but when powering multiple pedals an isolated DC power supply is the best option as it produces the least amount of background noise. There are three options to choose from when powering guitar pedals:
9V Battery (left), 9V Battery in Pedal (center), space for 9V battery in pedal (right) Effects pedals can be plugged into the mains but only if you use an AC adapter. This is because the AC power that comes out of the wall is too strong for a guitar pedal so the AC adapter will convert it into DC power so the voltage drops to a suitable level.
Guitar effects pedals need a power supply to operate properly, and you need to make sure the power supply is compatible for each pedal you're using. In this article, I'll explain the three options you have in terms of powering your pedals and the pros and cons of each of them.
Let's contrast this with batteries. Batteries are a direct DC source for your pedals. There's no conversion. No need to introduce any additional rectifiers and capacitors into your signal chain. When batteries are at 100% they're pure clean consistent DC power.
Do effects pedals need a battery?
Most pedals require a 9V battery, but some need an 18V or 24V battery so make sure you check this on the back of the pedal or on the manufacturer's guide. 9V Battery (left), 9V Battery in Pedal (center), space for 9V battery in pedal (right) Effects pedals can be plugged into the mains but only if you use an AC adapter.
This is a special power output for pedals that some guitarists believe sounds better when the battery inside of it is dying. Many players believe certain pedals sound better with batteries for this reason. Overdrive, fuzz, gain, wah, and distortion pedals often sound better with a battery.