A Safer, Self-Healing Polymer Battery

Lithium-ion batteries are notorious for spontaneously combusting, with seemingly so many ways that it can be triggered. While they are a compact and relatively affordable rechargeable battery for hobbyists, damage to the batteries can be dangerous and lead to fires.

Several engineers from the University of Illinois have developed a solid polymer-based electrolyte that is able to self-heal after damage, preventing explosions.The material can also be recycled without the use of high temperatures or harsh chemical catalysts. The results of the study were published in the Journal of the American Chemical Society.

As the batteries go through cycles of charge and discharge, they develop branch-like structures known as dendrites. These dendrites, composed of solid lithium, can cause electrical shorts and hotspots, growing large enough to puncture internal parts of the battery and causing explosive chemical reactions between the electrodes and electrolyte liquids. While engineers have been looking to replace liquid electrolytes in lithium-ion batteries with solid materials, many have been brittle and not highly conductive.

The high temperatures inside a battery melt most solid ion-conducting polymers, making them a less attractive option for non-liquid electrolytes. Further studies producing solid electrolytes from networks of cross-linked polymer strands delays the growth of dendrites but produces structures that are too complex to be recovered after damage. In response, the researchers at University of Illinois developed a similar network polymer electrolyte where the cross-link point undergoes exchange reactions and swaps out polymer strands. The polymers stiffen upon heating, minimizing the dendrite problem and more easily breaking down and resolidifying the electrolyte after damage.

Unlike conventional polymer electrolytes, the new polymer also shows properties of conductivity and stiffness increasing with heating. The material dissolves in water at room temperature, making it both energy-efficient and environmentally friendly as well.

3D Printing Batteries

We’ve all gotten pretty adept at 3D printing keychains and enclosures. Some people can even 3D print circuit boards to an extent. But the real goal is a Star Trek-style replicator that just pushes out finished products. Printing different components would be a key technology and unless you want to supply external power, one of those components better be a battery or other power source like a solar cell. A recent paper entitled Additive Manufacturing of Batteries explores this technology. The paper is behind a paywall, but you can probably find a copy if you are persistent.

Some of the techniques are pretty exotic. For example, holographic lithography can produce high-performance lithium-ion batteries. However, some of the processes didn’t sound much different than some of the more common printing techniques employed by desktop printers, although with more exotic materials. For example, some batteries can be made with inkjet printing and even fused deposition printing. Continue reading “3D Printing Batteries”

PackProbe Reports Laptop Battery Health

The 18650 cell has become a ubiquitous standard in the lithium battery world. From power drills to early Tesla vehicles, these compact cells power all manner of portable devices. A particularly common use is in laptop batteries, where they’re often built into a pack using the Smart Battery System. This creates a smart battery that can communicate and report on its own status. PackProbe is a software tool built to communicate with these batteries, and you might just find it comes in handy.

The code runs on the WiFi-enabled Arduino Yún by default, but can be easily modified to suit other Arduino platforms. Communicating over SMBus using the Arduino’s I2C hardware, it’s capable of working with the vast majority of laptop batteries out there which comply with the Smart Battery System. With that standard being minted in 1994, it’s spread far and wide these days.

It’s a great way to harvest not only the specifications and manufacturing details of your laptop battery pack, but also to check on the health of the battery. This can give a clear idea over whether the battery is still usable, as well as whether the cells are worth harvesting for those in the recycling business.

You’re not limited to just the Arduino, though. There’s a similar tool available for the ESP8266, too.

New Part Day: SMD Batteries

Here’s a tip for all you retrocomputing enthusiasts or even anyone with an old computer in the garage. Go remove the battery. Yes, that old mid-90s desktop has a battery inside for the real-time clock, and it’s a ticking time bomb. Batteries leak, and they’ll spew goo all over the circuit board, irreparably damaging your piece of electronic nostalgia. This goes for all electronics, too: that badge collection is going to be a pile of broken fiberglass in a decade. Remove your batteries now.

While lithium cells soldered to a motherboard will leak, now there might be a new technology that will allow our modern electronics to last for decades. It’s a solid state battery. The FDK Corporation is now handing out samples of a battery that looks like a large SMD cap. They come on tape and reel, and they’ll never leak.

Thanks to massive investments in battery research, batteries are getting more power-dense, and form factors are getting weird. Your AirPods need a battery somewhere, and manufacturers are figuring out the best way to put a battery into something that can be assembled by a pick and place machine. This battery is the answer to these problems, packing a 3.0 V, 140 μAh lithium cobalt pyrophosphate cell into a package that is just 4 mm by 2 mm by 2 mm. It’s a battery that looks a surface mount component, and it’s installed the same way: this is a pick-and-placeable battery.

While the capacity of this battery is tiny — a 1225 coin cell has a capacity of about 50 mAh, and this battery has a capacity of 140 μAh, three whole orders of magnitude smaller — sometimes that’s all you need. If you need a battery for a RTC, this SMD battery will work.

How Smart Is The Grid?

Marketing and advertising groups often have a tendency to capitalize on technological trends faster than engineers and users can settle into the technology itself. Perhaps it’s no surprise that it is difficult to hold back the motivation to get a product to market and profit. Right now the most glaring example is the practice of carelessly putting WiFi in appliances and toys and putting them on the Internet of Things, but there is a similar type of fiasco playing out in the electric power industry as well. Known as the “smart grid”, an effort is underway to modernize the electric power grid in much the same way that the Internet of Things seeks to modernize household appliances, but to much greater and immediate benefit.

A Cutler-Hammer industrial breaker ominously predicts the coming confusion in the smart grid arena.
Photo by Bryan Cockfield

To that end, if there’s anything in need of modernization it’s the electric grid. Often still extensively using technology that was pioneered in the 1800s like synchronous generators and transformers (not to mention metering and billing techniques that were perfected before the invention of the transistor), there is a lot of opportunity to add oversight and connectivity to almost every part of the grid from the power plant to the customer. Additionally, most modern grids are aging rapidly at the same time that we are asking them to carry more and more electricity. Modernization can also help the aging infrastructure become more efficient at delivering energy.

While the term “smart grid” is as nebulous and as ill-defined as “Internet of Things” (even the US Government’s definition is muddied and vague), the smart grid actually has a unifying purpose behind it and, so far, has been an extremely useful way to bring needed improvements to the power grid despite the lack of a cohesive definition. While there’s no single thing that suddenly transforms a grid into a smart grid, there are a lot of things going on at once that each improve the grid’s performance and status reporting ability.

Continue reading “How Smart Is The Grid?”

PSA: Don’t Let Kids Eat Lithium Batteries

We get a lot of press releases at Hackaday, but this one was horrific enough that we thought it was worth sharing. Apparently, some kids are accidentally eating lithium coin cell batteries. When this happens with bigger cells, usually greater than 20 millimeters (CR2032, CR2025, and CR2016) really bad things happen. Like burning esophaguses, and even death.

The National Capital Poison Center has done some research on this, and found that 14% of batteries swallowed over the past two years came from flameless candles like the ones above. We know some of our readers also deal with batteries in open trays, which are apparently pretty dangerous for children.

The National Capital Poison Center’s website has an entire page dedicated to battery safety, which is probably worth a read if you deal with batteries and small children on a regular basis. Should an incident occur, there’s even a hotline to call for assistance.

So, please, don’t swallow batteries, or let children put them in their mouths. After the break, a Canadian PSA song about not putting things in your mouth.

Continue reading “PSA: Don’t Let Kids Eat Lithium Batteries”

Counting Laps And Testing Products With OpenCV

It’s been about a year and a half since the Batteroo, formally known as Batteriser, was announced as a crowdfunding project. The premise is a small sleeve that goes around AA and AAA batteries, boosting the voltage to extract more life out of them. [Dave Jones] at EEVblog was one of many people to question the product, which claimed to boost battery life by 800%.

Batteroo did manage to do something many crowdfunding projects can’t: deliver a product. Now that the sleeves are arriving to backers, people are starting to test them in the wild. In fact, there’s an entire thread of tests happening over on EEVblog.

One test being run is a battery powered train, running around a track until the battery dies completely. [Frank Buss] wanted to run this test, but didn’t want to manually count the laps the train made. He whipped up a script in Python and OpenCV to automate the counting.

The script measures laps by setting two zones on the track. When the train enters the first zone, the counter is armed. When it passes through the second zone, the lap is recorded. Each lap time is kept, ensuring good data for comparing the Batteroo against a normal battery.

The script gives a good example for people wanting to play with computer vision. The source is available on Github. As for the Batteroo, we’ll await further test results before passing judgement, but we’re not holding our breath. After all, the train ran half as long when using a Batteroo.