by w2aew @ youtube.com
The Humanalight is a simple single-cell flashlight kit that will produce usable light, even from a “dead” AA battery. Circuits like these are often called a Joule Thief. This term has been applied to just about any circuit that allows you to boost the voltage from nearly depleted batteries for some other low-power application – such as lighting an LED. Strictly speaking, a Joule Thief circuit is an Armstrong style blocking oscillator that uses a bifilar wound transformer and relies on the saturation characteristics of the core to produce oscillation. This flashlight uses a simple two-transistor relation oscillator. A description of the circuit is given, and its operation is examined by viewing the waveforms on an oscilloscope. The proceeds from the sale of this kit benefit the “Ears To Our World” charity which provides self-powered radios and other technology to rural, impoverished and remote regions of the world.
Circuit Walkthrough: A single cell LED light - [Link]
by Afrotechmods @ youtube.com
A beginner’s guide to different battery chemistries and how to choose the right battery for your project.
How to choose a battery: A battery chemistry tutorial - [Link]
by Solarcycle @ instructables.com:
Power Stacker is a portable, modular, USB rechargeable lithium-ion battery pack. Stack them together for power hungry projects or separate them for smaller projects with this modular system. The Gerber, BOM, and .STL files are available below.
Power Stacker does what other USB rechargeable batteries have failed to do, and that’s the ability to combine together for increased battery capacity or separate in to many small batteries for smaller projects. You can literally use the same Power Stacker batteries for many years across many applications!
Stackable USB Rechargeable Battery System - [Link]
by Martha Heil @ umdrightnow.umd.edu:
Researchers at the University of Maryland have invented a single tiny structure that includes all the components of a battery that they say could bring about the ultimate miniaturization of energy storage components.
The structure is called a nanopore: a tiny hole in a ceramic sheet that holds electrolyte to carry the electrical charge between nanotube electrodes at either end. The existing device is a test, but the bitsy battery performs well. First author Chanyuan Liu, a Ph.D. student in materials science & engineering, says that it can be fully charged in 12 minutes, and it can be recharged thousands of time.
Billion Holes Can Make a Battery - [Link]
by Jim @ jimlaurwilliams.org:
I got a couple of cheap ($1.29) 1A USB LiPo chargers since I’m doing more and more LiPo/LiIon powered stuff. I mostly discharged a recycled 18650 cell for a test load and it looks like it does charge at nearly 1A. Two LEDs – red charging, green (mine is blue) fully charged. Seems like a pretty ideal cheap device.
Cheap USB LiPo charger notes - [Link]
Fully Assembled Solar Cell Controller Board and Sun Tracker for Arduinos /Raspberry Pi / Phone Charging. Plus Open Source Drivers.
Ever wanted to build your own Solar Powered Raspberry Pi or Arduino system? That is what this Kickstarter is all about!! SunAir and SunAirPlus are 3rd Generation Solar Charging and Sun Tracking Boards designed by Dr. John C. Shovic at SwitchDoc Labs.
You can use this board to power your projects and add a servo or stepper motor to allow it to track the sun using photoresistors to generate even more power! It incorporates a number of outstanding features in a very compact, inexpensive single fully assembled and tested PC Board.
SunAir Solar Power Controller Board/Tracker/Phone Charger - [Link]
By Eric Mack @ gizmag.com:
There’s another promising contender in the race to supplant the dominance of lithium-ion and metal-hydride based batteries in the world of energy storage. New research from the Karlsruhe Institute of Technology’s (KIT’s) Helmholtz Institute Ulm (HIU) details the development of an electrolyte that can be used in new magnesium-sulfur battery cells that would be more efficient and inexpensive than the dominant types of batteries in use today.
New electrolyte to enable cheaper, less toxic magnesium-sulfur-based batteries - [Link]
A battery charger is a device used to energize a rechargeable battery by driving an electric current through it. The charging protocol depends on the size and type of the battery being charged. Some battery types have high tolerance for overcharging and can be recharged by connection to a constant voltage source or a constant current source; simple chargers of this type require manual disconnection at the end of the charge cycle, or may have a timer to cut off charging current at a fixed time.
The MCP1631HV multi-chemistry reference design board is used to charge one, two, three or four NiMH batteries or one or two cell Li-Ion batteries. The board uses the MCP1631HV high speed analog PWM and PIC16F883 to generate the charge algorithm for NiMH, NiCd or Li-Ion batteries. It is used to evaluate Microchip’s MCP1631HV in a SEPIC power converter application. As provided, it is user programmable using on board pushes buttons. The board can charge NiMH, NiCd or Li-Ion batteries. It provides a constant current charge (Ni based chemistry) and constant current / constant voltage (Li-Ion) with preconditioning, cell temperature monitoring (Ni based) and battery pack fault monitoring. Also, the charger provides a status or fault indication. It automatically detects the insertion or removal of a battery pack.
The MCP1631 multi-chemistry battery charger reference design is a complete stand-alone constant current battery charger for NiMH, NiCd or Li-Ion battery packs. When charging NiMH or NiCd batteries the reference design is capable of charging one, two, three or four batteries connected in series. If Li-Ion chemistry is selected, the board is capable of charging one or two series batteries. This board utilizes Microchip’s MCP1631HV (high-speed PIC® MCU PWM TSSOP-20). The input voltage range for the demo board is 5.3V to 16V.
Multi-Chemistry Battery Charger from Microchip - [Link]
Dilshan Jayakody has published a new build, an automatic car battery charger:
This is modified version of commonly available automatic car battery charger system. I obtain original layout of this charger from one of the commercially available Chinese car battery charger and modified some of the sections of original schematic to improve the performance and stability of the system. This charger is mainly based on LM311 comparator and 2×12V 4A transformer.
Simple automatic car battery charger - [Link]
Steve Taranovich @ edn.com:
Panasonic Corporation has developed a pin-shaped Lithium Ion battery (CG-320, nominal capacity 13mAh) with a diameter of 3.5mm and a weight of 0.6g.
This offering will give designers an added choice to their power sources for new designs among paper and thin film batteries but is not an earth-shattering battery breakthrough. EaglePicher has had small LiIon batteries for implantables for a while and Quallion has a 2.6mm diameter by 10.9mm height in their QL0002l device for implantables and sensors—BUT—it has only 1.5 mAh capacity.
Tiny pin-shaped Lithium Ion battery - [Link]