Gatling himself developed several electrically powered versions back around the turn of the century.
And they worked. But at that time they would have needed very long extension cords to be of any combat use. There wasn't much interest in perfecting electrically-powered Gatlings until the advent of jet aircraft. Much of the development of early electrically powered Gatlings for aircraft use was done back in the early 1950s at the Armour Research Foundation in Chicago. And some such guns were used as far back as the early days of U. S. involvement in Vietnam. Remember "Puff the Magic Dragon"?
"Puff the Magic Dragon" was a highly developed piece of equipment before my arrival in Vietnam (1969). Essentially a C130 cargo plane (turbo-prop, four engines) modified for the air support role, featuring 7.62mm mini-guns, also known as the Vulcan Cannon (several configurations existed, including at least one with a 105mm howitzer). The mini-guns had a cyclic rate of 6000 RPM, but were commonly "tuned down" to about 2000 RPM (approx. 333 RPM per barrel of the 6-barreled gun, so heat build-up and barrel burn-out were serious concerns in use). Usually deployed in a circular or oval orbit over a target area, allowing the side of the aircraft armed with guns to engage ground targets. When firing the sound (from the ground anyway) was a high-pitched buzzing sound, not unlike a heavy-duty zipper being pulled, and the tracer elements in the projectiles looked very much like a red laser beam descending from the sky to the ground. Very impressive armament.
Mini-guns (7.62mm) were also deployed on Army attack helicopters (AH-1 Cobra and UH-1 Huey gunships), and I saw a couple of fixed installations with mini-guns mounted in towers for perimeter or area defense.
Some USAF attack aircraft were equipped with the 20mm Vulcan Cannons, basically a larger caliber model of similar design. 20mm ammunition included armor-piercing and high-explosive versions, allowing use against armored vehicles and fortified positions, or against troop concentrations.
Later developments included the A10, a turbo-fan armored attack plane essentially built around the 30mm version of the modern Gatling gun design. A very effective tank killer weapon, usually firing depleted uranium projectiles for extreme armor-piercing capability. The USAF has announced the A10 to be discontinued, but after several years the "Warthogs" continue to serve.
All of those systems started with development work revolving around a vintage US Army Gatling Gun, .45-70 caliber, modified with electrical drive and improved ammo feeding mechanisms. The company names sticking in my mind from that development period are General Electric and Vulcan Systems.
The only original Gatling Gun that I have ever personally examined was a 7X57mm Mauser example, made by Colt, reportedly for a Latin American military where the 7mm Mauser was the standard service cartridge. It was in the usual caisson-mounted configuration, but was equipped with armor plate protection panels for the gunner and loader. I'm sure several other versions exist (or existed).