Jesus Echavarria has tipped us with his latest project. A car battery monitor in a Relay form Factor. Unfortunately only hardware details are given and no details on software. He writes:
Hi all! I’m really busy this year so I can’t post all the projects where I’m involved. Here’s one of the design I do last year for a client. He wants to measure the voltage of a car battery and set a couple of alarms when voltage falls below a defined values. Also, he wants to put the device in the relay box of the car, so the design needs to have a relay form factor to easy integration. So, after a couple of iterations, here’s the final design of the battery monitor.
The project start around a year ago. The client wants a device to integrate in the relay box of some vehicles to monitor the voltage of the battery (12V nominal value). He wants two alarms at two different voltages. The alarm output will activate other external relays for advertising the low level of the battery, so I use a couple of small SSR for this outputs. Also he wants to configure the time to enable / disable alarms: once the device detect a voltage lower or higher than configurated values, the device needs to wait some time (configurable) before actívate or desactivate the alarms.
Vehicle Battery monitor on a automotive relay form factor – [Link]
Designers working on line-powered systems are in luck…
Designers working on line-powered systems are in luck; whilst wasting power is always bad, a few mA of waste don’t really matter. When working on battery powered systems, every bit of energy helps – an efficient switching regulator can be helpful in various ways.
First of all, the holy grail of battery powered systems is connecting your electronics directly to the battery. Controllers with a wide input range can “float” around the battery voltage, thereby eliminating switching losses completely. Sadly, this is not always possible – LCD modules and various other elements demand fixed voltages or tight voltage ranges.
In this case, a highly efficient voltage regulator can be valuable. Microchip’s MCP1640 boasts with a 96% conversion rate, and furthermore it comes with a power-saving shutdown mode as shown in figure A.
Due to the high switching frequency – the PWM modules work at 500KhZ – the inductors required are small; their weight is comparable with that of SMD resistors, thereby ensuring “minimal grief” when used in surface-mount form factors. […continue reading]
LiFePo4wered/Pi+ is simply a better version of the LiFePo4wered/Pi3 and the LiFePowered/Pi. These devices are all designed to solve the issue of power supply to the raspberry pi. LiFePo4wered is simply a high-performance battery power system which is acting as an option for raspberry pi projects where the likes cellphone adapters and USB power banks cannot fit in.
Power is one of the significant factors in the use of the Raspberry, most Raspberry Pi projects are usually plugged into a wall power adapter which at some could impact on the mobility and portability of the project, but with the LiFePo4wered/Pi+ you don’t have to worry about plugging your project into a wall socket. It can power a Raspberry Pi for up to nine hours from its battery (depending on installed battery size, Raspberry Pi model, attached peripherals, and system load) and can be left plugged in continuously.
LiFePo4wered/Pi+ might probably end up as the best source of power supply to the raspberry pi, and the primary advantage is that it works with all models of the Raspberry Pi. The LiFePo4wered/Pi+ can provide a steady continuous current supply of 2A to the Raspberry Project; this is usually like the max most Raspberry Pi project will use an unlikelihood one will be capped at that max but the general standard of about 700mA.
The following are some of the features of the LiFePo4wered/Pi+:
1500 mAh 3.2 V LiFePO4 battery: Uses a Lithium iron phosphate that provides safety, high power density and extended cycle life of 2000+ cycles. The battery can also be used as a UPS.
Optional 600 mAh, 3.2 V LiFePO4 cell: This is merely a smaller battery for low power applications or when there is power loss in the main battery.
2 A continuous load current: Can supply this with 1500mAH battery option or using an external source of power.
A Smart charge controller:
Over-charge protection: This feature allows the device to stay plugged in continuously without exploding because it stores the extra charge to help it serve as a UPS when needed.
Auto-adjusting charge current: Regular charge current can be up to 1.5 A when used with high power chargers. However, it will automatically reduce current when needed not to overwork low power sources when they are used.
Customizable MPP (Maximum Power Point) voltage: This helps to obtain maximum efficiency when powered directly from suitably sized solar panels.
On/off button: provides convenient boot/shutdown triggers even in headless setups, with the press and hold function to prevent accidental activation (external button can be added).
Green PWR LED: This indicates the Raspberry Pi power state, and it provides feedback to the user. External LED can be included.
Red CHRG LED: This tells the user when there is a power loss and when there is a need to charge the batteries.
Wake timer: This allows the Raspberry Pi to be off until when it’s needed for low duty cycle applications.
Real-time clock: It keeps track of time and makes sure the raspberry pi comes on at a programmed time.
Autoboot: Makes the Raspberry Pi run whenever there is sufficient battery power, or when an external power supply is available.
Auto shutdown: Automatically shuts the Raspberry Pi down when there is a power loss or after a programmed amount of time.
Application watchdog: can alert a user by flashing the PWR LED or trigger a shutdown/reboot if the user application fails to service the timer within a configurable amount of time.
Compatibility: Works with every known model of Raspberry Pi, this includes Raspberry Pi Model A+, Model B+, Raspberry Pi 2, Raspberry Pi 3, Raspberry Pi 3 Model B+, Raspberry Pi Zero and Raspberry Pi Zero W.
Hackers Friendly: It has convenient connection points for input power, 5 V output power, switched battery power, external button and LEDs(Light Emitting Diodes), and MPP customization.
LiFePO4wered daemon: This is responsible for the auto shutdown and real-time clock (RTC) duties.
Command line tool: allows simple configuration and access to all features.
Shared library, language bindings: C/C++, Python, and Node.js bindings allow integration into user programs.
A team of researchers from National Renewable Energy Laboratory (NREL) has discovered a new method for developing a rechargeable non-aqueous magnesium-metal battery. A proof-of-concept paper published in Nature Chemistry. It described how the scientists pioneered a method to enable the reversible chemistry of magnesium metal in the noncorrosive carbonate-based electrolytes and tested the concept in a prototype cell. The technology possesses many high potential advantages over conventional lithium-ion batteries. Some upgrades over Li-ion battery with this new kind of battery will be, higher energy density, greater stability, and lower cost.
NREL researchers Seoung-Bum Son, Steve Harvey, Andrew Norman, and Chunmei Ban are co-authors of the Nature Chemistry white paper, “An Artificial Interphase Enables Reversible Magnesium Chemistry in Carbonate Electrolytes” working with a Time-of-flight secondary ion mass spectrometry. The device enables them to investigate material degradation and failure mechanisms at the micro- to nano-scale.
Chunmei Ban, a scientist in NREL’s Materials Science department and corresponding author of the paper, said,
Being scientists, we’re always thinking: what’s next? The dominant lithium-ion battery technology is approaching the maximum amount of energy that can be stored per volume, so there is an urgent need to explore new battery chemistries that can provide more energy at a lower cost.
Seoung-Bum Son, a former NREL postdoc and scientist at NREL and first author of the paper, thinks this finding will provide a new avenue for magnesium battery design.
An electrochemical reaction powers a battery as ions flow through a liquid (electrolyte) from the negative electrode (cathode) to the positive electrode (anode). For batteries using Lithium, the electrolyte is a salt solution containing lithium ions. It’s also important to make the chemical reaction reversible for the battery to recharge again.
Magnesium (Mg) batteries theoretically contain almost twice as much energy per volume as of lithium-ion batteries. But previous research confronted an obstacle. The chemical reactions of the conventional carbonate electrolyte created a layer on the surface of magnesium that prevented the battery from recharging. The magnesium ions could flow in a reverse direction through a highly corrosive liquid electrolyte, but that blocked the possibility of a successful high-voltage magnesium battery.
The researchers developed an artificial solid-electrolyte interphase from polyacrylonitrile and magnesium-ion salt that protected the surface of the magnesium anode. This protected anode and significantly improved performance of the cell.
In addition to being more readily available than lithium, magnesium has other advantages over the more established battery technology. Firstly, magnesium releases two electrons which is higher lithium’s one, thus giving it the potential to deliver nearly twice as much energy as lithium. And second, magnesium-metal batteries do not experience the growth of crystals that can cause short circuits and consequently dangerous overheating and even fire, making magnesium batteries much safer than lithium-ion batteries.
So couple months ago, GreatScott made a video where he designed a circuit. Nothing too innovative, just the same TP4056 charger the MT3608 Boost combined on one PCB. He did add a Lipo protection circuit though, initially using the same DW01. But then, the Aha moment from this video, he found a footprint compatible IC the FS312F-G – which is set at 2.9v! Way healthier for your cell’s longevity!
First of all I had to redraw all his work in Eagle (As I wont be using a cloud based service like EasyEDA for obvious reasons) and then order the PCBs. I added two boost circuits since I had the board space, as I can imagine needing dual voltages at some point (for example if that reverse LCD needed 12v and the Pi needed 5v – i could run both off one board.
Lipo Charge/Boost/Protect board in 18650 cell holder format – [Link]
Climate Change have been a crucial factor taken into consideration by the Australian researchers from Royal Melbourne Institute of Technology before creating the first rechargeable proton battery. After considering all available options about cost and availability of the materials needed, the researchers in Melbourne decided to make a proton battery to meet up with the alarming increase of energy needs in the world.
Lead researcher Professor John Andrews says, “Our latest advance is a crucial step towards cheap, sustainable proton batteries that can help meet our future energy needs without further damaging our already fragile environment. As the world moves towards inherently variable renewable energy to reduce greenhouse emissions and tackle climate change, requirements for electrical energy storage will be gargantuan”. The proton battery is one among many potential contributors towards meeting this enormous demand for energy storage. Powering batteries with protons has the potential to be more economical than using lithium ions, which are made from scarce resources. Carbon, which is the primary resource used in our proton battery, is abundant and cheap compared to both metal hydrogen storage alloys and the lithium needed for rechargeable lithium-ion batteries.
Here’s how the battery works; During charging, protons generated during water splitting in a reversible fuel cell are conducted through the cell membrane and directly bond with the storage material with the aid of electrons supplied by the applied voltage, without forming hydrogen gas. In electricity supply mode, this process is reversed. Hydrogen atoms released from the storage lose an electron to become protons once again. These protons then pass back through the cell membrane where they combine with oxygen and electrons from the external circuit to reform water. In simpler terms, carbon in the electrode bonds with the protons produced whenever water is split via the power supply’s electrons. Those protons pass through the reversible fuel cell again to form water as it mixes with oxygen and then generates power.
According to Andrews, “Future work will now focus on further improving performance and energy density through the use of atomically-thin layered carbon-based materials such as graphene, with the target of a proton battery that is truly competitive with lithium-ion batteries firmly in sight.” With the kind of progress made, it might not be now, however, lithium-ion batteries might be put out of the market in the nearest future.
The team is looking to improve their research, ameliorate the battery’s performance, and exploit other better materials like graphene to further put this proton battery to its fullest potential. Developments like will be needed if we are going to create sustainable future especially with the ever rising cost and demand of Energy.
One thing is sure, the Energy Industry is going to be disrupted now or in the future, and this proton battery innovation could just be one of the potential ways.
Mare @ e.pavlin.si designed a single cell Li-Ion battery pack simulator to facilitate the testing process of a new device.
Modern battery operated portable devices use smart battery packs. Every new development of an electronic medical device must follow strict design flow defined by world-wide or local regulatory
directives. The development process of any such device using smart battery pack requires specific operating conditions to meet the testing criteria. When smart battery pack is one of the main power sources the host system should be tested with several battery states. The testing is necessary during development, validation and later in production testing.
Low cost single cell Li-Ion battery pack simulator – [Link]
Researchers at the University of Warwick in the UK have developed sensors which measure the internal temperature and electrode potential of Lithium batteries. The technology is being developed by the Warwick Manufacturing Group (WMG) as a part of a battery’s normal operation. More intense testings have been done on standard commercially available automotive battery cells.
If a battery overheats it becomes a risk for critical damage to the electrolyte, breaking down to form gases that are both flammable and can cause significant pressure build-up inside the battery. On the other hand, overcharging of the anode can lead to Lithium electroplating, forming a metallic crystalline structure that can cause internal short circuits and fires. So, overcharging and overheating of a Li-ion battery is hugely damaging to the battery along with the user.
The researchers at Warwick developed miniature reference electrodes and Fiber Bragg Gratings (FBG) threaded through a strain protection layer. An outer coat of Fluorinated Ethylene Propylene (FEP) was applied over the fiber, ensuring chemical protection from the corrosive electrolyte. The end result is a sensor which has direct contact with all the key components of the battery. The sensor can withstand electrical, chemical and mechanical stress faced during the normal operation of the battery while still giving accurate temperature and potential readings of the electrodes.
The device includes an in-situ reference electrode coupled with an optical fiber temperature sensor. The researchers are confident that similar techniques can also be developed for use in pouch cells. WMG Associate Professor Dr. Rohit Bhagat said,
This method gave us a novel instrumentation design for use on commercial 18650 cells that minimizes the adverse and previously unavoidable alterations to the cell geometry,
The data from these internal sensors are much more precise than external sensing. This has been shown that with the help of these new sensors, Lithium batteries that are available today could be charged at least five times faster than the current rates of charging.
This could bring huge benefits to areas such as motor racing, gaining crucial benefits from being able to push the performance limits. This new technology also creates massive opportunities for consumers and energy storage providers.
Recom’s first evaluation board allows engineers to effortlessly test the functionality of the R-78S switching regulator, which boosts a AA battery or external supply voltage to 3.3V for low power IoT applications. By Julien Happich @ eenewseurope.com:
The R-78S Evaluation Board demonstrates the performance of the R-78S which boosts single-cell AA battery voltage of 1.5V up to a stable 3.3V. This guarantees much higher energy capacities and reduces maintenance costs compared to button or coin cell batteries. This will effectively extend the operation lifetime of an application since the boost converter continues to operate at input voltages as low as 0.65V.
R-78S switching regulator boosts a AA battery to 3.3V – [Link]
You have a Raspberry Pi project, but it’s no good stuck to a wall! JuiceBox Zero is the simplest way to properly power your Pi Zero. by Samuel Anderson @ kickstarter.com:
I had an amazing project for Raspberry Pi that needed to be battery powered. I searched and found a few boards that served the purpose. Unfortunately, they were a bit cumbersome, and sadly, they weren’t “plug-n-play” with Raspberry Pi!
When the Pi Zero was released, I instantly saw the potential its tiny form factor provided for truly mobile inventions. But to be truly mobile, it can’t be tethered to a power source. Just imagine how useless a smartphone would be if it had to be plugged into the wall!
The project is live on kickstarter and available for funding.