Feel The Hum Of Electricity Between Your Legs

August 10, 2011 by Mike Szczys 21 Comments

Here’s a little eye candy for motorcycle enthusiasts everywhere. This is the newest iteration of [Julian’s] electric motorcycle. He obviously knows what he’s doing because everything fits into the frame in a way that is still very pleasing to the eye. But this is actually slimmed down from the original design. If you take a look a back at some of his older posts you’ll see that the four relatively small lithium batteries are a new addition.

The frame was designed to hold four lead-acid batteries. Those things really take up a lot of space and add considerable weight to the vehicle. His recent upgrade was also accompanied by a re-gearing that allows him to reach higher speeds (although he doesn’t say what the top speed actually is). You can’t really see it above, but [Julian] included a wooden insert where the tank on a gasoline motorcycle would have been. It houses control switches as well as a 48V voltmeter. It’s a fantastic finishing touch like the cherry on a sundae.

Bypassing Manufacturer-imposed Battery Lockouts

July 21, 2011 by Mike Nathan 62 Comments

sony_battery_cell_swapping

When [Barret] went to use his camera the other day it kept shutting down on him, and upon inspecting the battery, he found that it was a bit swollen. Knowing that he needed a replacement, he turned to an aftermarket battery he had sitting around, but grew pretty annoyed when his Sony Cybershot camera would not accept it.

Apparently a recent firmware update causes his camera to reject non-Sony batteries, a situation he describes as “battery DRM”. There was no way he was going to pony up another $50 to Sony instead of using the perfectly good $10 battery he already had, so he decided to rectify the issue himself.

He stripped both batteries of their plastic coatings, revealing the lithium cells and their charging circuits. He desoldered the PCB from his Sony battery, transplanting it to his aftermarket battery after a little bit of trimming. He wrapped everything up with some tape and gave his franken-battery a spin. It worked a treat, and he was so satisfied with it that he did a similar swap in his aging Logitech mouse.

As more and more companies lock competitors out of the user-replaceable consumables market, these sorts of hacks are certain to become more and more prevalent.

Automotive Battery Voltage Monitor

July 13, 2011 by Mike Nathan 32 Comments

car_battery_voltage_monitor

[Rajendra’s] car had just about all the bells, whistles, and gauges he could dream of, but he thought it was missing one important item. In an age where cars are heavily reliant on intricate electrical systems, he felt that he should have some way of monitoring the car’s battery and charging system.

To keep tabs on his car’s electrical system, he built a simple device that allows him to monitor the battery’s instantaneous voltage when the car is powered off, as well as the charging voltage across the battery when the car is running. A PIC16F1827 runs the show, using a simple voltage divider network to step the input voltage down to an acceptable level for use with the PIC’s A/D conversion channel. The resultant measurements are output to a four digit 7 segment display, mounted on the front of the device.

He says that the voltage monitor works quite well, and we’re sure he feels a lot better about the health of his car’s charging system. For anyone interested in keeping closer tabs on their car, he has a circuit diagram as well as code available on his site.

DIY Battery Reconditioner Saves Old Rechargeable Batteries From The Landfill

June 26, 2011 by Mike Nathan 20 Comments

rechargeable_battery_reconditioner

Instructables user [msuzuki777] had amassed quite a collection of batteries over the years, but was finding that some of his rechargeable AA and AAA cells seemed to be at the end of their useful life. After reading some information at the Battery University regarding the restoration process for nickel-based batteries, he figured he might as well try building a battery reconditioner of his own.

He worked through several designs that either flat-out did not work, or had issues that limited the number of batteries he could simultaneously recondition. After reading about this rechargeable battery capacity tester we featured a few months back, he was ready to give the project one more try.

It seems that the third try was the charm, because his FET-based design worked quite well. He ended up wiring two FETs to each battery, which are connected via a relay. The batteries get discharged until the voltage drops down to 1V, at which point one FET is turned off, allowing the batteries reach their target voltage of 0.4V more slowly.

Despite the self-proclaimed messy layout of his circuit, [msuzuki777] is quite happy with the results. He has been able to recover several batteries, which is a fantastic alternative to letting them decay in a landfill.

Diagnosing Diseases Like MacGyver

May 1, 2011 by Mike Nathan 28 Comments

pancratitis_test

If you ever watched MacGyver as a kid, you know that given any number of random objects, he could craft the exact tool he would need to get out of a sticky situation. If he ever made his way into the medical research field, you could be sure that this test for Acute Pancreatitis would be among his list of accomplishments.

Designed by University of Texas grad student [Brian Zaccheo], the Acute Pancreatitis test seen in the image above looks as unassuming as it is effective. Crafted out of little more than foil, jello, and milk, the test takes under an hour to diagnose patients while costing less than a dollar.

The test works by checking the patient’s blood for trypsin, an enzyme present in high concentrations if they are suffering from pancreatitis. Once a few drops of the patient’s blood is placed on the gelatin layer of the test, it is left to sit for a bit, after which sodium hydroxide is added. If elevated trypsin levels are present, it will have eaten through the gelatin and milk protein, creating a pathway for the sodium hydroxide to reach the foil layer. If the foil is dissolved within an hour, a circuit is formed and a small LED lights up, indicating that the patient has acute pancreatitis.

The test really is ingenious when you think about it, and will be a huge help to doctors practicing in developing countries, under less than ideal working conditions.

[via PopSci via Gizmodo]

Cellphone Battery Mouse Modification

April 19, 2011 by Mike Szczys 23 Comments

Ever wanted to increase the battery performance in your wireless mouse? [Davetech] shows you the way with this guide for converting a mouse from AA to lithium batteries. We were delighted by his hack-tacular approach that seems to have a nice little work-around at each step in the process. He grinds down the plastic battery housing that is molded into the original mouse body, then uses an old Compact Flash card connector as a set of spring terminals for a Nokia cellphone battery. This battery has more capacity and recharges faster than non-Lithium AA cells. But unfortunately the spring terminals didn’t quite reach the recessed batter contact. No problem, he just builds up solder on the battery to bridge the gap.

[Davetech] manages to fit the entire battery inside the mouse and the pointing-device still works. Your mileage may vary by model (both battery and mouse). It is necessary to take the battery out of the mouse for recharging, but since this only happen about every couple of weeks thanks to the extended capacity it’s not too much of a hassle. Perhaps someone could carry this to the next level by adding a USB port and the necessary charging circuitry?

Auxiliary Battery Pack For Field Operations

April 18, 2011 by Mike Nathan 11 Comments

portable_battery_pack

Ham operator [Ken – wa4mnt] wrote us to share a small project that he uses nearly every time he goes out in the field. His portable sealed lead acid battery pack (PDF) always ensures that he has a 12v power source at his fingertips, both for fun as well as in emergency situations.

The battery pack is pretty simple, and includes a 12v, 17ah battery strapped into a light aluminum chassis which he fabricated. The battery is secured with zip ties, so it can easily be swapped out or replaced without much fuss. The frame also sports a tiltable 4w, 17.5v solar panel that keeps the battery topped off and ready to go at all times. He stuck a voltmeter to the top of the battery to keep an eye on things, and he employs a 10A fuse to make sure he doesn’t fry any sensitive radio components should something go wrong.

The battery pack is pretty compact when you think about it, and we imagine it would be great to have on hand for a wide array of outdoor activities. Even if you’re not into Ham field operations, it’s hard to argue with its usefulness during power outages.

[Ken] doesn’t appear to have any published plans for the chassis or the electronic portion of the pack, but we’re pretty sure he would share if asked.