A Supercapacitor Might Just Light Your Way One Day

January 12, 2020 by Jenny List 32 Comments

Sometimes the simplest hacks are the most useful ones, and they don’t come much simpler than the little supercapacitor LED flashlight from serial maker of cool stuff [Jeremy S. Cook]. Little more than an LED, a supercapacitor, USB plug, and couple of resistors, it makes a neat little flashlight that charges from any USB A power socket and delivers usable light for over half an hour.

It’s neat, but on its own there’s not much to detain the reader until it is revealed as a “Hello World” supercapacitor project from an article in which he delves into the possibilities of these still rather exotic components. Its point is to explore their different properties when compared to a battery, for example a linear voltage drop in contrast to the sharp drop-off of a chemical cell. In the video below the break we see him try a little boost regulator to deliver a constant voltage, with consequent severe loss of lighting time for the LED. It’s by this type of experimentation that we learn our way around a component unfamiliar to us, and the article and video are certainly worth a look if you’ve never used a supercapacitor before.

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See How Wildly Different Air Conditioners Can Be (On The Inside)

December 15, 2019 by Donald Papp 16 Comments

Air conditioners are easy to take for granted. From refrigerators to climate control, most of us would miss them dearly if they disappeared. That’s part of what draws [Josh Levine]’s interest in air conditioners, and he has provided an interesting tour of several different units and how different they can be, despite all working in basically the same way.

That white PCB is crucial (for running the bluetooth speaker and LED flashlight, that is.)

One way that air conditioners try to stand out is by being quiet, and the bulk of noise comes from the fans and the compressor. One unit (the Haier Serenity) aimed to be the quietest unit possible, but while this effort had mixed results at best it is still interesting to see [Josh] give a tour of the different ways they tried to reduce noise (YouTube, embedded below). Noise-limiting elements include the unusual step of using separate motors for the indoor and outdoor fans, and even little counterweights to ensure they are perfectly balanced, just like wheel weights on automobile tires.

Another notable air conditioner is the Zero Breeze, a portable unit that was the product of a Kickstarter campaign. Features included (either bizarrely or predictably, you be the judge) a bluetooth speaker and an LED flashlight. [Josh] more than half suspected the product would never actually ship, but was pleasantly surprised. Not only did it deliver, it turned out to be a pretty nice design with only a couple of mildly head scratching moments (YouTube, also embedded below).

There are a few more to check out in the roundup on [Josh]’s web site, which he also compares and contrasts with his own DIY unit which we featured in the past.

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Assemble Your Own Modular Li-Ion Batteries

April 23, 2018 by Drew Risinger 50 Comments

Low-voltage DC power electronics are an exciting field right now. Easy access to 18650 battery cells and an abundance of used Li-Ion cells from laptops, phones, etc. has opened the door for hackers building their own battery packs from these cheap cells. A big issue has been the actual construction of a pack that can handle your individual power needs. If you’re just assembling a pack to drive a small LED, you can probably get by with spring contacts. When you need to power an e-bike or other high power application, you need a different solution. A spot welder that costs $1000 is probably the best tool, but out of most hackers’ budget. A better solution is needed.

Enter [Micah Toll] and his Vruzend battery connectors, whose Kickstarter campaign has exceded its goal several times over. These connectors snap onto the ends of standard 18650 cells, and slot together to form a custom-sized battery pack. Threaded rods extend from each plastic cap to enable connection to a bus bar with just a single nut. The way that you connect each 18650 cell determines the battery pack’s voltage and current capability. There are a couple of versions of the connector available through the campaign, and the latest version 2.0 should allow some tremendously powerful battery pack designs. The key upgrade is that it now features corrosion-resistant, high-power nickel-plated copper busbars allowing current up to 20A continuous. A side benefit of these caps instead of welded tabs is that you can easily swap out battery cells if one fails or degrades over time. Continue reading “Assemble Your Own Modular Li-Ion Batteries” →

Prepping For Power Outages

December 19, 2017 by Jenny List 268 Comments

When the mains power goes, we are abruptly brought face-to-face with how many of the devices and services we take for granted rely upon it. Telephones for instance, where once they were attached to the wall by a cable, now they are a cordless device with a mains-powered base station. Your cellphone can fill that gap, but a modern smartphone with a battery life of under a day is hardly a reliable long-term solution. Meanwhile modern heating systems may still burn gas or fuel oil, but rely on an electric pump for circulation. Your kitchen is full of electrically-powered white goods, your food is preserved by an electric refrigerator, even your gas cooker if you have one will probably expect a mains supply.

When the power goes out we might say that we instantaneously travel back a couple of centuries, but the reality is that our ancestors in 1817 wouldn’t have been in the same mess we are, they had appropriate solutions to surviving a wickedly cold winter when electricity was still something of a gleam in [Michael Faraday]’s eye. In short, they were prepared in a way most of us are not. That’s a shame, so let’s take a closer look sensible modern preparedness.

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Bluetooth Speaker In A Bag

December 8, 2017 by James Hobson 10 Comments

[VanTourist] — irked by what he sees as complicated project videos — has demonstrated that you can build a high quality, multi-function Bluetooth speaker inside three hours.

Using simple hand tools — primarily a crimper, wire stripper, razor cutter and some glue — he’s packed this repurposed GoPro accessory bag with quite a bit of tech. The main components are a Bluetooth amplifier with a spiffy knob, and a pair of 15W speakers, but he’s also added a 1W LED flashlight, 1A and 2.1A charging ports, a battery charge monitor display, and pilot cover toggle switches for style points. Despite all that crammed into the bag, there’s still a bit of room left to pack in a few possessions! You can check out the build pictures here, or the video after the break.

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Hacklet 110 – Optical Microscopy Projects

June 4, 2016 by Adam Fabio No comments

Humans have always wanted to make small things bigger. To see that which is unseen with the naked eye. The inventor of the original microscope happened sometime in the 1600’s, though the inventor is still contested. Some say it was Cornelis Drebbel, while others say Hans Lippershey. Galileo Galilei’s compound microscope is probably the most well-known ancient magnifier. Regardless of who created the device, hackers, makers, engineers, and scientists have used microscopes to study mysteries of biology, geology, electronics, and just about anything else you can imagine.

This is a fitting topic for this week’s Hacklet at is aligns well with the Citizen Scientist challenge round of the Hackaday Prize which began on Monday. Making quality microscopes more widely available is one of many great starting ideas for an entry. Let’s take a look at some of the best microscopy projects on Hackaday.io!

We start with [J. Kha] and Armed Microscope. [J. Kha] was one of the backers of the original uArm over at Kickstarter. He also does quite a bit of work with electronics. After fighting with a cheap USB microscope, he realized he had the perfect platform to control it. Microscopes usually are stationary, with the object being viewed moved on a stage. [J. Kha] turned things upside down by mounting the microscope on his uArm. An Arduino Yun controls the system. The Yun also allows him to stream the microscope’s video over the internet using the mjpg-streamer library. [J. Kha] did have some power issues at first, but he’s got his regulators all sorted out now.

Next we have [andyhull] with Adding a light touch to a “classic” microscope. A lucky dumpster find netted [Andy] a pile of old broken microscopes. From this he was able to build a working classic stereo scope. This was a Gillet & Sibert stereo compound scope. Like most microscopes of its time, the old GS used standard incandescent or halogen lights for illumination. The old bulbs were long gone, and would have been a pain to replace. [Andy] switched his scope over to LED illumination. He ended up using a commercially available LED “bulb” designed to replace type 1157 automotive tail light bulbs. This type of LED is designed to run on 12 volt power which simplifies the wiring. The small LED flashlight in a custom mount also provides a bit of help for opaque subjects.

Next up is [Andre Maia Chagas] with Flypi – cheap microscope/experimental setup. Flypi is [Andre’s] entry in the 2106 Hackaday Prize. Flypi is more than just a microscope, it’s a 3D printed data collection and image analysis device for hackers and scientists alike. A Raspberry Pi 2 or 3 controls the show. Images come in through Pi Camera with an M12 lens. The Pi runs some open source Python code allowing it to acquire and analyze images. It also has an Arduino as a co-processor to handle anything a particular experiment may need – like RGB LEDs, heaters, manipulators, you name it. Andre sees Flypi as having uses in everything from fluorescence imaging to optogenetics and thermogenetics.

Finally we have [Jarred Heinrich] with Stagmo: Microscope Stage Automator. Positioning samples under high magnification requires a steady hand. Trying to image them makes things even harder. To help with this, microscopes have stages. Fine lead screws manually controlled by knobs allow the user to precisely position any subject. Automated stages are available as well, but they can get quite expensive. [Jarred] recognized that the microscope stage is an X-Y platform like any CNC, laser, or 3D printer. He used an Arduino and a motor shield to control a couple of stepper motors. The motors are coupled to the stage knobs with rubber belts. While the mounting system looks a little wobbly, but it got the job done, and didn’t require any modifications to the microscope itself.

Optical microscopes are just one type of scope you’ll find on Hackaday.io. There are also atomic force microscopes, scanning electron microscopes, and more! I’ll cover those on a future Hacklet. If you want to see more awesome optical microscopy projects, check out our new optical microscope projects list! If I missed your project, don’t be shy, just drop me a message on Hackaday.io. That’s it for this week’s Hacklet. As always, see you next week. Same hack time, same hack channel, bringing you the best of Hackaday.io!

Prototype Sodium Ion Batteries In 18650 Cells

December 2, 2015 by Al Williams 70 Comments

French researchers have announced a prototype of an 18650 sodium-ion battery. If you’ve bought a powerful LED flashlight, a rechargeable battery pack, or a–ahem–stronger than usual LASER pointer, you’ve probably run into 18650 batteries. You often find these inside laptop batteries and –famously– the Tesla electric vehicle runs on a few thousand of these cells. The number might seem like a strange choice, but it maps to the cell size (18 mm in diameter and 65 mm long).

The batteries usually use lithium-ion technology. However, lithium isn’t the only possible choice for rechargeable cells. Lithium has a lot of advantages. It has a high working voltage, and it is lightweight. It does, however, have one major disadvantage: it is a relatively rare element. It is possible to make sodium-ion batteries, although there are some design tradeoffs. But sodium is much more abundant than lithium, which makes up about 0.06% of the Earth’s crust compared to sodium’s 2.6%). Better still, sea water is full of sodium chloride (which we call salt) that you can use to create sodium.

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