
Buddies Battery – Revolution to power banks, or just a niche gadget?
Do you recall the little earphone cleaner that launched on Kickstarter a while ago, having all the tools needed to clean Airpods packed neatly inside a tube? Well, the Buddies team has just sent us their next invention, a modular power bank that you can attach tools to named Buddies Battery.
The concept involves utilizing a novel rechargeable Li-ion cell known as 21700, which is a larger variant of the commonly used 18650 found in flashlights and certain power banks. What sets Buddies 21700 apart from other 21700 cells is that it has both positive and negative electrodes on one side, making it an ideal match for the accompanying tools.
Buddies Battery is by far the smallest among them and has a range of attachments, let’s try it out and see how well it works.


We believe the Buddies team has sent us the single set. Inside the bright yellow semi-open box is one Buddies Battery, one 5000 mAh 21700 battery, one flashlight attachment and one USB charger attachment. They all ship separated and protected in foam. The box holds down every item securely to prevent them from scratching. The surface has a rubberized body in ivory color and a fluro-yellow accent. It is more sporty than techy from the look. The design prevents slipping and small dings from outdoor use.

The 21700 is an upscaled version of the common 18650, which itself is shaped like a classic AA battery/dry cell. It has a hard metal shell under the wrapping, able to be carried around without an external case.

Buddies is designed to fit with one accessory at a time, once fitted it merges into the body. A standard flashlight/torch is attached by default. The design is very minimal, it turns on automatically once the brass contact is inserted to contact the battery, eliminating the need of an on/off button. One fully charged 21700 battery can keep it on for around 20 hours. The Li-ion battery is less sensitive to climate and doesn’t lose power quickly in the cold. They can hold power without too much insulation.
With a full-length clear light shade, the light illuminates both the front and the side of Buddies Battery. It is not a super-powerful 1000 lumens death ray, but is still considerably brighter than the light on your phone and handy when it is dark. It can double as a lantern as the light beam is not overly focused, but you might want something bigger to hit the trail at night. Still, it is very handy as a backup, during a blackout, or when you have to work under your car hood in the dark. Its rear end is flat and stands up on a flat surface.

We tested out the power bank attachment next. Swapping it from light to charger is very simple by sliding it off. The charger contains one “female” socket for USB-C cable. You can use a male-male Type-C cable to charge Android devices, or a Type-C to Lightning cable to charge Apple iPhones. To keep the setup compact, we used a short USB cable to test the charging.
Buddies Battery can charge my iPhone reasonably fast. While it is not certified to PD or other fast charge standards, it is comparable to plugging into a wall outlet. I was surprised by how much power this little cell has held – a full 5000mAh which is enough to fully charge an average iPhone more than one time. The recharge speed was pretty stable and Buddies did not heat up like some power banks would. The setup is slightly lighter than comparable 5000mAh power banks, but more or less equal to a 10000mAh power bank if an extra cell is carried. Still, you can fly with it checked into luggage, unlike the banned Lipos.


So back to the question – is Buddies Battery the next big thing to power banks, or if it is just a niche gimmick? The answer is neither. Despite the unorthodox design approach, Buddies Battery is still very much a power bank. You will be using it to charge up your gadgets most of the time, although you also get a flashlight and lantern at a little cost of extra weight and size, which can come super useful. I have been carrying a card-tools kit in my wallet for years, only making use of it twice. But both events could have cost me hundreds if I didn’t have the tool, so I left it in. It is always a good idea to be prepared. Buddies Battery might be niche, but it is also useful and practical.