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”

Ask Hackaday: What’s Your Etchant?

Although the typical cliché for a mad scientist usually involves Bunsen burners, beakers, and retorts, most of us (with some exceptions, of course) aren’t really chemists. However, there are some electronic endeavors that require a bit of knowledge about chemistry or related fields like metallurgy. No place is this more apparent than producing your own PCBs. Unless you use a mill, you are probably using a chemical bath of some sort to strip copper from your boards.

The standard go-to solution is ferric chloride. It isn’t too tricky to use, but it does work better hot and with aeration, although neither are absolutely necessary. However, it does tend to stain just about everything it touches. In liquid form, it is more expensive to ship, although you can get it in dry form. Another common etchant is ammonium or sodium persulphate.

pcbyThere’s also a variety of homemade etchants using things like muriatic acid and vinegar. Most of these use peroxide as an oxidizer. There’s lots of information about things like this on the Internet. However, like everything on the Internet, you can find good information and bad information.

When [w_k_fay] ran out of PCB etchant, he decided to make his own to replace it. He complained that he found a lot of vague and conflicting information on the Internet.  He read that the vinegar solution was too slow and the cupric acid needs a heated tank, a way to oxygenate the solution, and strict pH controls. However, he did have successful experiments with the hydrochloric acid and peroxide. He also used the same materials (along with some others) to make ferric chloride successfully.

Continue reading “Ask Hackaday: What’s Your Etchant?”

How To Put A Jag On Your School Roof

Did you ever commit any pranks in your time at high school, college, or university? Maybe you moss-painted a rude word on the wall somewhere, or put a design in a sports field with herbicide, or even worse, slow-release fertiliser. [Roman Kozak] and his friends went far further than that last summer when they replicated some of the most famous student pranks; they put a Jaguar S type car on the roof of their school. And now the dust has settled, he’s posted an account of how they did it.

jag-on-roof-guy-cuttingOf course, putting a car on the roof is a significant challenge, particularly when you only have the resources of a high-school student. Ensuring the roof was strong enough for a car, and then hiring a crane to do the deed, was beyond them. They therefore decided to take the wheels and outer body panels of a car and mount them on a wooden frame to give the appearance of a car.

They needed a statement vehicle and they didn’t have a huge budget, so it took them a while to spot a for-parts Jaguar S type which when it came into their possession they found only had a fault with its reverse gear. Some hard work removed the panels, and the rest of the car was taken for scrap.

Frenetic work as the term end approached gave them their frame, and a daring midnight raid was mounted to winch the parts to the roof with a pulley. The result was so popular with their classmates and teachers that they owned up to the prank rather than preserve their anonymity. We think these young scamps will go far.

This is definitely the first car-on-roof prank we’ve brought you on Hackaday, but it’s not the first to be done. [Roman] and his friends cited an MIT prank as their inspiration, but the daddy of car-on-roof stunts has to go to Cambridge University students in the 1950s. Their Austin might be a lot smaller than the MIT Chevy or [Roman]’s Jag, but they got it onto their roof in one piece as a full car rather than a facsimile of one.

Important note: The author would like to state for the record that she and her friends were somewhere else entirely and had solid alibis when in summer 1993 the logo of Hull University Union Technical Committee appeared in the lawn outside Hull University Union. We’re sure that commenters will be anxious to set their own records straight for posterity in a similar manner.

$10 Raspberry Pi Zero W Adds WiFi and Bluetooth

The Raspberry Pi was born on February 29th which means we’re only three years away from its second birthday, and a new hardware release from the Pi Foundation is becoming somewhat of a tradition. This year is no different: a new Raspberry Pi has been announced. The Raspberry Pi Zero W is the latest iteration of the Pi foundation’s tiny and extremely inexpensive single board computer. It’s a Raspberry Pi Zero with WiFi and Bluetooth.

The specs of the new Pi Zero W are nearly identical to the previous incarnation of the non-W Zero. It sports a 1GHz single-core processor, 512 MB of RAM, features Mini HDMI and USB OTG ports, uses a micro USB port for power, features the now-standard 40-pin header with four additional pins for composite video and a reset button. This board, like the second hardware revision of the Pi Zero, also features a CSI camera connector.

Of course, the big feature is the addition of WiFi and Bluetooth. The Pi Zero W adds the wireless functionality from the Raspberry Pi 3B. That’s 802.11n and Bluetooth 4.0.

The Pi Zero’s claim to fame was, of course, the price. The original Pi Zero was at first a bit of hardware glued to the cover of the MagPi magazine, later to sell for just $5 USD. The Raspberry Pi Zero W is priced at just $10.

Continue reading “$10 Raspberry Pi Zero W Adds WiFi and Bluetooth”

Printer Scrap Becomes FPGA Devboard

These days, if you want to start learning about FPGAs, it can be a daunting experience. There’s a huge variety of different platforms and devboards and it can be difficult to know where to start. [RoGeorge] decided to take a different tack. Like a 16-year-old drag racer, he decided to run what he brung – a printer control panel cum FPGA development board (Romanian, get your Google Translate on).

[RoGeorge] was lucky enough to score a couple of seemingly defective control panels from HP Laserjets discarded by his workplace. Seeing potentially good parts going to waste, like keypads and LCDs, he decided to investigate them further – finding a 50,000 gate Xilinx Spartan IIE running the show. Never one to say no to opportunity, [RoGeorge] dived in to learning how to work with FPGAs.

The forum posts are a great crash course in working with this sort of embedded FPGA platform. [RoGeorge] covers initial mapping of the peripherals on the board & finding a JTAG connector and programming solution, before moving on to basic FPGA programming and even covers the differences between sequential programming on microcontrollers and the parallel operation of FPGAs. Even if you don’t intend to get down and dirty with the technology, spend half an hour reading these posts and you’ll be far more knowledgeable about how they work!

In the end, [RoGeorge] showed how to teach yourself to work with FPGAs for the price of a couple of programming cables – not a mean feat by any means. It’s a testament to the hacker spirit, and reminds us of [SpriteTM]’s efforts in hacking hard drive controllers.

An Old 68000 SBC is New Again

[Jeff Tranter] has done a number of retrocomputing projects. But he wanted to tackle something more substantial. So he set out to build a 68000-based single board computer called the TS2 that he found in a textbook. He’s documented it in a series of blog posts (about 30 posts, by our count) and a video that you can see below.

The 68000 had a very rational architecture for its day. A flat memory space was refreshing compared to other similar processors, and the asynchronous bus made hardware design easier, too. While most CPUs of the era assumed bus devices could perform their service in a fixed amount of time, the 68000 used a handshake with devices to allow them to take the time they needed. Most other CPUs had to provide a mechanism for a slow device to stall the bus which was complicated and, in many cases, less efficient.

Continue reading “An Old 68000 SBC is New Again”

I am Science Fiction Incarnate; I am Handle

This is the first official look at Boston Dynamics’ new robot design, called Handle, and it’s a doozy. They are a trusted source of cutting-edge real-world robotics, which is good. If this came from an unknown source we’d be scrambling to debunk it as fake. This robot shows incredible utility, the likes of which has been relegated to the computer graphics of the movie and video game industries.

Impressive ability to keep 'hands' stationary in 3D space
Impressive ability to keep ‘hands’ stationary in 3D space

At the beginning of the month, we saw a demonstration of the robot but it was simply cellphone footage of a conference hall video. This is a crystal clear 60fps video from Boston Dynamics themselves with a few juicy details to go along with it. Chief among them (for us anyway) is that this prototype has a battery range of about 15 miles between charges. The efficiency is due in large part to the wheeled nature of the beast. It balances on two wheels, but the design attaches those wheels to two fully articulated legs rather than directly to the frame of the body.

The result is a quadruped that is distinctly not human in appearance but can perform well in similar environments and with similar tasks. Handle is capable of offsetting its body weight, allowing the front limbs to pick up heavy objects while maintaining balance. The combination of both electric and hydraulic actuators let it perform feats like jumping over four-foot high objects. The independence of each wheel is shown off with ramps to simulate uneven terrain.

Bravo BD. We can’t wait to see Handle wheeling down the street placing smile-adorned boxes on each stoop as it revolutionizes home delivery. Oh, and kudos on the 80’s-style freeze frame at the end of the video below.

Continue reading “I am Science Fiction Incarnate; I am Handle”