Portable Pi Power Pack Makes For Petite Projects

Since the Pi Zero was released, there have been many attempts to add a power bank. Cell phone batteries are about the same size as a Pi Zero, after all, and adding a USB charging port and soldering a few wires to a Pi is easy. The PiSugar is perhaps the cutest battery pack we’ve seen for the Pi Zero, and it comes in a variety of Hats compatible with the Pi, capable of becoming a small display, a keyboard, or any other thing where a small, portable Linux machine is useful.

The core of this build is a small circuit board the size of a Pi Zero. Attached to this board is a 900mAh battery, and the entire assembly is attached to the Pi Zero with a set of two spring clips that match up with with a pair of pads on the back of the Pi. Screw both of these boards together, and you have a perfect, cableless solution to adding power to a Pi Zero.

But the PiSugar doesn’t stop there. There are also cases, for a 1.3 inch LCD top, a 2.13 inch ePaper display, an OLED display, a camera, a 4G module, and something that just presents the pins from the Pi GPIO header. This is an entire platform, and if you print these parts in white plastic, they look like tiny little sugar cubes filled to the brim with electronics and Linux goodness.

Yes, you’ve seen 3D printed Pi cases before, but nothing in the way of an entire platform that gives you a Pi Zero in an extensible platform that can fit in your pocket and looks like sweet, sweet cubes of sucrose.

Keep ‘Em Flying with this Monster DIY Battery

If you’ve spent an afternoon at the sticks of a remote-controlled aircraft, you’re probably well aware of the great limiter for such exploits: battery life. In the days when most RC aircraft were gas powered it was easy to cart along some extra fuel to keep the good times rolling, but now that everything except big scale models are using electric motors, RC pilots are looking for better ways to charge their batteries in the field.

Though it might seem counter-intuitive, [Adam Pyschny] is of the opinion that the best way to keep his quadcopter batteries charged is to simply use another, much bigger, battery. Rather than mess around with inverters or generators, he can simply use a DC-to-DC battery charger and his huge custom-built battery pack to keep flying.

The pack contains 36 Samsung INR18650-35E 3500mAh cells, which gives it a total capacity of 454Wh. At 1965 grams (4.3 lbs) the pack isn’t exactly a featherweight, but it’s significantly lighter than carting a small generator or even a lead-acid battery to the field.

[Adam] designed a slick case in FreeCAD and printed it in Minadax ASA-X filament, which is specifically designed for outdoor use. A particularly nice detail in the case is that the balance connector (used to charge the cells) is cleanly integrated into the side of the pack, rather than just flapping around in the breeze; which annoyingly seems the norm even on commercially produced batteries.

An interesting next step for this project would be the addition of a solar panel and charge controller to help recover in-between charges. Beyond an automated platform to swap the batteries for you, a DIY pack like this might be the easiest way to maximize the amount of time your RC aircraft are in the air where they belong.

Assemble Your Own Modular Li-Ion Batteries

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.

Vruzend v2 Battery Caps.

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”

3D Printed Battery Pack Keeps Old Drill Spinning

The greatest enemy of proprietary hardware and components is time. Eventually, that little adapter cable or oddball battery pack isn’t going to be available anymore, and you’re stuck with a device that you can’t use. That’s precisely what happened to [Larry G] when the now antiquated 7.2V NiCd batteries used by his cordless drill became too hard to track down. The drill was still in great shape and worked fine, but he couldn’t power the thing. Rather than toss a working tool, he decided to 3D print his own battery pack.

The 3D modeling on the battery pack is impeccable

He could have just swapped new cells into his old pack, but if you’re going to go through all that trouble, why not improve on things a little? Rather than the NiCd batteries used by the original pack, this new pack is designed around readily available AA NiMH batteries. For the light repairs and craft work he usually gets himself into, he figures these batteries should be fine. Plus he already had them on hand, and as we all know, that’s half the battle when putting a project together.

Interestingly, the original battery pack was wired in such a way that it provided two voltages. In older tools such as this one, this would be used for rudimentary speed control. Depending on which speed setting the drill is on, it would either connect to 4 or 6 cells in the original pack. [Larry] didn’t want to get involved with the extra wiring and never used the dual speeds anyway, so his pack only offers the maximum speed setting. Though he does mention that it may be possible to do PWM speed control in the battery itself via a 555 timer if he feels like revisiting the project.

[Larry] tells us the pack itself was rendered completely from scratch, using only the original battery pack and trial-and-error to get the fit perfect. He reused the side-mounted release buttons to save time, but otherwise everything is 3D printed in PETG for its strength and chemical resistance.

This is an entry in Hackaday’s

Repairs You Can Print contest

The twenty best projects will receive $100 in Tindie credit, and for the best projects by a Student or Organization, we’ve got two brand-new Prusa i3 MK3 printers. With a printer like that, you’ll be breaking stuff around the house just to have an excuse to make replacement parts.

The Trouble With Cordless Power Tools

If you grow up around a small engineering business you are likely to gain something of an appreciation for power tools. You’ll see them of all ages, sizes, manufacturers, and technologies. When thinking of the power tools constantly on hand in the workshop of a blacksmith like my dad for instance, I’m instantly seeing a drill and an angle grinder. The drill that most comes to mind is a Makita mains powered hand drill, and given that I remember the day he bought it to replace his clapped-out Wolf in 1976, it has given phenomenal service over four decades and continues to do so.

41 years of hard use, and still going strong.
41 years of hard use, and still going strong…

Of course, the Makita isn’t the only drill in his possession. A variety of others of different sizes and speeds have come and gone over the years, and there is always one at hand for any given task. The other one I’d like to single out is I think the most recent acquisition, a Bosch cordless model he bought several years ago. It’s similar in size and capabilities to the Makita save for its bulky battery pack, and it is a comparably decent quality tool.

So, we have two drills, both of similar size, and both of decent quality. One is from the mid 1970s, the other from the end of the last decade. One is a very useful tool able to drill holes all day, the other is little more than a paperweight. The vintage model from the days of flared trousers is a paperweight, you ask? No, the not-very-old Bosch, because its battery pack has lost its capacity. The inevitable degradation due to aged cell chemistry has left it unable to hold enough charge for more than maybe a minute’s use, and what was once a tool you’d be glad to own is now an ornament.

Continue reading “The Trouble With Cordless Power Tools”

Rescuing A Proprietary Battery Pack With A Cell From A Camera

If you have an older handheld battery-powered device, you may be fighting a diminishing battery capacity as its lithium-ion cells reach the end of their life. And if you are like [Foxx D’Gamma], whose device is an Alinco DJ-C7 handheld transceiver, you face the complete lack of availability of replacement battery packs. All is not lost though, because as he explains in the video below the break, he noticed that a digital camera battery uses a very similar-sized cell, and was able to graft the camera battery into the shell of the Alinco pack.

Cracking open the Alinco pack, he was rewarded with the rectangular Li-Ion cell and two PCBs, one for the connector and another for the battery management circuitry. By comparison the camera battery had a much smaller battery management PCB, and it fit neatly into the space vacated by the Alinco cell once those covers had been removed. A fiddly soldering job to attach the connector PCB, and he was rewarded with a working Alinco pack and an unexpected bonus when he found out that the transceiver was a dual band model.

Along the way he’s at pains to point out the safety aspects of handling Li-Ion cells, and to ensure that the polarity of the cell is correct. It’s also worth our reminding readers that these packs must always be accompanied by their battery management circuitry. The result though is pleasing: a redundant piece of equipment made obsolete by a proprietary battery, given a new lease on life.

Continue reading “Rescuing A Proprietary Battery Pack With A Cell From A Camera”

Tesla Model S Battery Pack Teardown

We’ve heard a lot about the Tesla Model S over the last few years, it’s a vehicle with a habit of being newsworthy. And as a fast luxury electric saloon car with a range of over 300 miles per charge depending on the model, its publicity is deserved, and that’s before we’ve even mentioned autonomous driving  driver-assist. Even the best of the competing mass-produced electric cars of the moment look inferior beside it.

Tesla famously build their battery packs from standard 18650 lithium-ion cells, but it’s safe to say that the pack in the Model S has little in common with your laptop battery. Fortunately for those of a curious nature, [Jehu Garcia] has posted a video showing the folks at EV West tearing down a Model S pack from a scrap car, so we can follow them through its construction.

The most obvious thing about this pack is its sheer size, this is a large item that takes up most of the space under the car. We’re shown a previous generation Tesla pack for comparison, that is much smaller. Eye-watering performance and range come at a price, and we’re seeing it here in front of us.

The standard of construction appears to be very high indeed, which makes sense as this is not merely a performance part but a safety critical one. Owners of mobile phones beset by fires will testify to this, and the Tesla’s capacity for conflagration or electrical hazard is proportionately larger. The chassis and outer cover are held together by a huge array of bolts and Torx screws, and as they comment, each one is marked as having been tightened to a particular torque setting.

Under the cover is a second cover that is glued down, this needs to be carefully pried off to reveal the modules and their cells. The coolant is drained, and the modules disconnected. This last task is particularly hazardous, as the pack delivers hundreds of volts DC at a very low impedance. Then each of the sixteen packs can be carefully removed. The packs each contain 444 cells, the pack voltage is 24 V, and the energy stored is 5.3 kWh.

The video is below the break. We can’t help noticing some of the rather tasty automotive objects of desire in their lot.

Continue reading “Tesla Model S Battery Pack Teardown”