The only USB-C AA battery I would buy for myself is the Zepath 3600

Last September, a company called Lumafield screened 1,000 cylindrical lithium-ion batteries To highlight the hidden dangers of underpricing. Around the same time, I found myself being tested Two great new types of AA batteries Which are recharged using USB-C cables.

You gave me an idea. Can we find Very better USB-C AA batteries by combining my own anecdotal tests and Lumafield proprietary scanning technology?

It seems the answer is yes! Knowing what I know now, the Zipath 3600 MW/h It’s the only rechargeable lithium-ion AA I’d buy for myself — though there’s USB-C in the charger, not in each individual cell.

The Zepath is the only one that passed the Lumafield test and mine with flying colors. It has more power than most competitors, is easy to use, and, incredibly, is one of the cheapest of its kind.

These batteries cost just $2.50 per cell, less than Panasonic’s popular nickel-metal hydride (NiMH) Eneloop batteries, all while lasting much longer than even the Eneloop Pros in my Game Boy Advance and high-powered flashlight.

It’s $20 for an eight-pack, and includes a clamshell charger with a magnetic closure. (Think of an earphone case, but much larger.) You can drop as many or as few batteries as you want into any of those eight slots—they’ll happily charge three empty batteries alongside three full ones, even if you arrange them in a zigzag pattern. It draws about 10 watts to charge all eight batteries at once, and less than 3 watts for a single pair. You can use either a USB-A-to-USB-C cable or the same type of USB-C PD charger you use for your phone or laptop.

Additionally, the charger has built-in safety precautions that prevent it from charging the wrong types of batteries. You’ll see eight hidden LEDs shine at the top of the case to indicate whether the battery is charging (flashing green), charged (steady green), or rejected (flashing red) because you accidentally put alkaline or NiMH inside instead.

Again, this means the only USB-C AA battery I recommend no I have a built-in USB-C port – but I have good reasons for that.

When Lumafield analyzed 12 different types of AA lithium-ion batteries Edgeincluding designs with built-in USB-C ports and those with clamshell USB-C chargers, almost every non-Zepath battery was of lower quality.

Some, like Paleblue, have tried cramming a small cell into the battery case to make room for a USB-C port. Others, like Coast, use a “box-in-a-box” design, where a smaller 14,400 cell (14mm x 40mm) is housed inside the larger battery.

In both cases, Lumafield’s Alex Howe found that most of them had relatively poor alignment and one had a negative overlap in the anode, the same troubling defect she discovered In a previous study, 1,000 larger cylindrical cells were performed. Almost every “good product” we scanned came with a shipping box, incl Phillips and Mobor. But the best was Zipath And very similar Operating power —And Zipath costs less.

“This battery has fairly straight alignment and even anode overlay (AOH). The assembly quality seems good. The electrodes really maximize the space available in the case. Overall, this is a good battery,” Howe described Zepath’s scans.

I had high hopes for the batteries from coast and Nightcorewith built-in USB-C ports and its brand reputation for creating high-quality flashlights Very smart customers. (Costco carries Coast batteries; this is not a fly-by-night brand.) But Howe thinks the Coast battery seems “a little wonky” with an unusually low anode. “There is still buildup, so this battery doesn’t seem completely unsafe, but I wouldn’t choose it over others in this group,” she noted.

And while you didn’t think about it Nightcore It was serious, and the company might have a quality control problem: Howe and I noticed that our batteries were a bit loose, with the top ends not always straight, and some of the cells Lumafield scanned had shorter protrusions and worse alignment than others, Howe said.

Batteries you may want to avoid are spywhich I see as having It has already been pulled from Amazon Since Lomafield discovered that one of the cells was completely deformed internally and had a negative anode. NTONPOWERwhich according to Howe had very poor electrode alignment; CZVVwhich had a “virtually non-existent” anode dangling along the bottom of the cell and its It also disappeared from AmazonSurprisingly, palea well-known brand as our inner bag cell seemed to have anodes that bent inward, which could cause a short circuit if you managed to touch it.

By the time I got Howe’s results, I didn’t mind giving up the USB-C port. I’ve actually discovered two practical downsides to built-in sockets.

One: shorter battery life. Zepath lasted a full hour and a half longer than the coast Modified Game Boy Advance game for the screen at maximum brightness; They lasted two hours longer My budget is a 1000 lumen flashlight. (See some of the results in my embedded video above.) And when I tried two different Nitecore sets in this Nebo flashlight, oddly enough, they didn’t work at all, either turning the high-powered LED into a blinking mess or refusing to stay lit.

Reason 2: This generation of built-in USB-C batteries is difficult to connect and disconnect. The plugs seem pretty tight for the most part, enough that I feel like I’m risking damaging the battery by forcefully inserting and removing them.

And while it may be annoying to remember to bring the Zepath charging case, it’s also possible to forget the four-pin USB-C charging cables that come with the built-in batteries. It’s nice to have an integrated outlet when you’re only charging one or two batteries.

Lithium-ion batteries are neither the battery nor the port or neither. Chemistry is still inherently flammable, even if these devices have a metal casing that protects them from repeated drops, and not all devices benefit from having batteries that reliably turn off around 1.5 volts until they are on the verge of death.

My flashlight has lasted much longer on low power with NiMH batteries, which die much slower, even if Li-ion batteries perform better on high power. So, even though I’ve added some Zepath batteries to my home, I won’t be getting rid of the Eneloops anytime soon.