The Science Behind Lithium Cell Characteristics And Safety

September 18, 2017 by Sean Boyce 58 Comments

To describe the constraints on developing consumer battery technology as ‘challenging’ is an enormous understatement. The ideal rechargeable battery has conflicting properties – it has to store large amounts of energy, safely release or absorb large amounts of it on demand, and must be unable to release that energy upon failure. It also has to be cheap, nontoxic, lightweight, and scalable.

As a result, consumer battery technologies represent a compromise between competing goals. Modern rechargeable lithium batteries are no exception, although overall they are a marvel of engineering. Mobile technology would not be anywhere near as good as it is today without them. We’re not saying you cannot have cellphones based on lead-acid batteries (in fact the Motorola 2600 ‘Bag Phone’ was one), but you had better have large pockets. Also a stout belt or… some type of harness? It turns out lead is heavy.

The Motorola 2600 ‘bag phone’, with a lead-acid battery. Image CC-BY-SA 3.0 source: Trent021

Rechargeable lithium cells have evolved tremendously over the years since their commercial release in 1991. Early on in their development, small grains plated with lithium metal were used, which had several disadvantages including loss of cell capacity over time, internal short circuits, and fairly high levels of heat generation. To solve these problems, there were two main approaches: the use of polymer electrolytes, and the use of graphite electrodes to contain the lithium ions rather than use lithium metal. From these two approaches, lithium-ion (Li-ion) and lithium-polymer (Li-Po) cells were developed (Vincent, 2009, p. 163). Since then, many different chemistries have been developed.

Continue reading “The Science Behind Lithium Cell Characteristics And Safety” →

A Noob’s Guide To McMaster-Carr

September 13, 2017 by Sonya Vasquez 179 Comments

For the penny-pinching basement hacker, McMaster-Carr seems like a weird go-to resource for hardware. For one, they’re primarily a B2B company; and, for two, their prices aren’t cheap. Yet their name is ubiquitous among the hacker community. Why? Despite the price, something makes them too useful to ignore by everyday DIY enthusiasts. Those of us who’ve already been enlightened by the McMaster-Carr can design wonders with a vocabulary of parts just one day away at the click of a button.

Today, this article is for those of us who have yet to receive that enlightenment. When used wisely, this source of mechanical everything brings us a world of fast parts at our fingertips. When used poorly, we find nothing but overpriced stock components in oversized shipping boxes.

Since we, the McMaster-Carr sages, are forever doomed to stuff our desk drawers with those characteristic yellow baggies till the end of time, we thought we’d give an intro to the noobs that are just beginning to flex their muscles with this almighty resource. Grab another cup of coffee as we take you on a tour of the good and good-grievances of McMaster-Carr.

Continue reading “A Noob’s Guide To McMaster-Carr” →

Superconference Speakers Revealed

September 13, 2017 by Mike Szczys 7 Comments

You’ll find the best hardware talks at the Hackaday Superconference. This year, we received over 140 proposals for a few dozen speaking slots. Although we’re still working through the proposals, today we can announce a few of the accepted and confirmed speakers so far. Below you’ll find about a third of the total slate of speakers.

Get Your Ticket to the Hackaday Superconference — they’re almost gone!

Continue reading “Superconference Speakers Revealed” →

The Components Are INSIDE The Circuit Board

September 11, 2017 by Bob Baddeley 56 Comments

Through-hole assembly means bending leads on components and putting the leads through holes in the circuit board, then soldering them in place, and trimming the wires. That took up too much space and assembly time and labor, so the next step was surface mount, in which components are placed on top of the circuit board and then solder paste melts and solders the parts together. This made assembly much faster and cheaper and smaller.

Now we have embedded components, where in order to save even more, the components are embedded inside the circuit board itself. While this is not yet a technology that is available (or probably even desirable) for the Hackaday community, reading about it made my “holy cow!” hairs tingle, so here’s more on a new technology that has recently reached an availability level that more and more companies are finding acceptable, and a bit on some usable design techniques for saving space and components.

Continue reading “The Components Are INSIDE The Circuit Board” →

These Twenty Assistive Technologies Projects Won $1000 In The Hackaday Prize

September 11, 2017 by Brian Benchoff 3 Comments

Today, we’re excited to announce the winners of the Assistive Technologies portion of The Hackaday Prize. In this round, we’re looking for projects that will help ensure a better quality of life for the disabled. Whether this is something that enhances learning, working, or daily living. These are the projects that turn ‘disability’ into ‘this ability’.

Hackaday is currently hosting the greatest hardware competition on Earth. We’re giving away hundreds of thousands of dollars to hardware creators to build the next great thing. Last week, we wrapped up the fourth of five challenges. It was all about showing a design to Build Something That Matters. Hundreds entered and began their quest to build a device to change the world.

There’s still one entry challenge remaining in The Hackaday Prize. Anything Goes is on right now and open to every idea imaginable. If you’re building a computer made of sand, awesome. Quadcopter hammock? Neat. This is the portion of the Hackaday Prize that’s open to the best ideas out there. It’s up to you to explain how your creation makes the world a little bit better place.

The winners of the Assistive Technologies challenge are, in no particular order:

Assistive Technologies Hackaday Prize Finalists:

Continue reading “These Twenty Assistive Technologies Projects Won $1000 In The Hackaday Prize” →

Hack Space Debris At Your Peril

September 11, 2017 by Steven Dufresne 41 Comments

Who has dibs on space debris? If getting to it were a solved problem, it sure would be fun to use dead orbital hardware as something of a hacker’s junk bin. Turns out there is some precedent for this, and regulations already in place in the international community.

To get you into the right frame of mind: it’s once again 2100 AD and hackers are living in mile-long space habitats in the Earth-Moon system. But from where do those hackers get their raw material, their hardware? The system abounds with space debris, defunct satellites from a century of technological progress. According to Earth maritime law, if space is to be treated like international waters then the right of salvage would permit them to take parts from any derelict. But is space like international waters? Or would hacking space debris result in doing hard time in the ice mines of Ceres?

Continue reading “Hack Space Debris At Your Peril” →

Scribble Your Way To Quick Printed Circuit Boards

September 10, 2017 by Jenny List 44 Comments

There are a variety of techniques employed by electronic constructors seeking the convenience of a printed circuit board without the inconvenience of making a printed circuit board. Dead bug style construction in which the components float on a spiders-web of soldered leads above a ground plane is one, Manhattan style construction in which pads made from small cut squares of bare copper-clad PCB are glued on top of a groundplane is another.

[Freestate QRP] has another take on this type of electronics, with what he calls “Scribble style” construction. He cuts away copper from bare board to create pads and rudimentary tracks, and for him the magic ingredient comes from his choice of an engineer’s scribe to do the job. This is where the “scribble” comes from, creating a pad is as simple as drawing it with the scribe.

Of course, this technique is not entirely new, constructors have been doing this type of work for years with Dremel tools, hand engraving tools, and similar. If you’ve ever tried to do it with a knife or scalpel you will know that it’s hardly an easy task with those hand tools so the prospect of another one doing a better job is rather interesting. He’s ready and able to demonstrate it in action, showing us a couple of RF circuits using the technique.

Have you tried this technique, or one like it? How did you get on, tell us in the comments. Meanwhile, you might like to read our own [Dan Maloney]’s look at dead bug and Manhattan construction.