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Energen DroneMax P40 Review

 & Jim Fisher Principal Writer, Cameras

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Energen DroneMax P40 Review - Batteries & Power
3.5 Good

The Bottom Line

The Energen DroneMax P40 is a big, heavy portable charger that can provide power to four DJI Phantom batteries simultaneously.

Pros & Cons

    • Portable design.
    • Includes charging cables for Phantom 3 and 4 batteries.
    • Dual USB charging ports.
    • Pricey.
    • Heavy.
    • Doesn't include its own charger.
    • Take eight hours to fully recharge.

DJI Phantom owners are used to only getting 20 to 25 minutes of flight on a fully charged battery. Drone pilots who need more time in the air stock up on batteries, but also need to buy an accessory charger to replenish more than one at a time. You can buy a three-battery charger for the Phantom 4 or a four-battery charger for the Phantom 3 from DJI for about $90, but those won't do much good if you're in the field without power. Enter the Energen DroneMax P40 ($399), which recharges up to four batteries at a time and includes a big internal battery that replenishes those four batteries in the field. Its priced much higher than the DJI options, but you're paying for convenience.

Design

The DroneMax is a big, heavy, silver brick with a rubberized black bumper. It measures 2.7 by 5.9 by 6.9 inches (HWD) and weighs 7.2 pounds. A zippered, padded carrying case is included. The case can be carried using an integrated hand strap, or with the included shoulder strap. Its main compartment holds the battery, and there's an interior zippered pocket that houses the included cables and documentation.

The P40 has four circular DC charging ports on its front, along with two female USB connectors, and another circular charging port that's used to recharge the high-capacity internal battery. Eight charging cables are included—four for DJI Phantom 3 drones and four for DJI Phantom 4 drones. You don't get a charger to replenish the battery itself. Instead, you need to use the charger that shipped with your drone to do so.

There's a power button in the middle of the face. Press it once and then again, holding it for three seconds, to start charging a connected battery. I took an empty Phantom 3 Advanced battery and connected it. The charger topped it off in about an hour—the same time that the standard DJI charger takes. After charging one battery, the P40's blue LED battery indicator showed that it had about 75 percent capacity remaining, exactly as expected.

That's in line with what Energen promises. You're supposed to be able to get four full charges out of its internal 27,236mAh battery, regardless of whether you're charging one battery four times or four batteries at once. You can expect to get a slower charge when utilizing all four ports, but Energen estimates that recharging four batteries will only take about an extra 10 minutes versus one. Of course, if you used the USB ports to charge other devices, you won't be able to get four full drone battery charges from the big power brick.

The battery itself takes about eight hours to fully recharge, although it can get to 90 percent capacity in less time. If you're using it at home, you can plug it into the wall to recharge while charging your drone batteries at the same time.

Conclusions

The Energen DroneMax P40 is, at its heart, just a really big battery. It delivers on its promises—it recharges DJI Phantom batteries, and does so when you're away from a power outlet. Are four extra flights worth a roughly $300 premium over DJI multi-chargers that must be plugged in to a wall to work? That's up to you. Just remember that, while being billed as portable, it's not lightweight. Putting it in the back of your SUV before going out for a weekend of camping and drone flying is not a problem, but I wouldn't want to hike a trail with it weighing down my backpack.

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Further Reading

Final Thoughts

Energen DroneMax P40 Review - Batteries & Power

Energen DroneMax P40 Review

3.5 Good

The Energen DroneMax P40 is a big, heavy portable charger that can provide power to four DJI Phantom batteries simultaneously.

About Our Expert

Jim Fisher

Jim Fisher

Principal Writer, Cameras

My Experience

Images, and the devices that capture them, are my focus. I've covered cameras at PCMag for the past 14 years, which has given me a front row seat for the changeover from DSLRs to mirrorless cameras, the smartphone camera revolution, and the emergence of drones for aerial imaging. I have extensive experience with every major mirrorless and SLR system, and am also comfortable using point-and-shoot and action cameras. As a Part 107 Certified drone pilot, I’m licensed to fly unmanned aircraft systems (UAS) for commercial and editorial purposes, and am knowledgeable about federal rules and regulations regarding drones.

The Technology I Use

I use all of the major camera systems on a regular basis, swapping between Canon, Fujifilm, L-Mount, Micro Four Thirds, Nikon, and Sony systems. I still find time to use Leica M rangefinders and Pentax SLRs on occasion, too. I keep an iPhone 13 in my pocket for the rare occasions I'm not carrying a camera.

I'm not a brand-specific photographer. For product review photos, I swap between a Canon EOS R5 and a Sony a7R IV. I use Flashpoint and Godox TTL lights and Peak Design tripods, and I most often reach for a Think Tank or Peak Design backpack to carry equipment.

When it comes to computers, I'm an unapologetic Mac person and have been for the past 20 years. I write in Pages and use Numbers for spreadsheets. I currently swap between an Intel i9 MacBook Pro and an Apple Silicon Mac Studio for writing and use a calibrated BenQ 32.5-inch with the Studio for photo and video editing. I rely on a LaCie 6big RAID for media storage. I also keep a PC around for gaming, but please don't tell my Macs about it; they'll get jealous.

I split time between several different software apps depending on the type of editing I'm doing. For Raw image processing, Adobe Photoshop Lightroom Classic is my standard. I pair it with a LoupeDeck CT console to supplement my keyboard and trackpad, and I lean on RNI All Films 5 presets when I want to give an image a film look. I use Apple Final Cut Pro for video editing.

My first digital camera was the Canon PowerShot Elph S200, and my first DSLR was the Pentax *ist DL. I have a soft spot for antique film gear. I still use a 1950 vintage Rolleiflex Automat TLR and love trying mid-century Leica lenses on film and digital alike. I mainly use whatever's in front of me for review for digital snaps, but I pick up either my Leica M Typ 240 or Pentax K-3 III Monochrome when I want to step away from review work. In my downtime, I enjoy bird watching, reading, video games, and both good and bad movies, especially in the sci-fi and horror genres.

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