by EEVblog @ youtube.com:
Want to include a small Lithium Ion or Lithium Ion Polymer battery into your next project? It’s easy! Dave gives you the low down on how they work and how to charge them and select a suitable charging IC.
NOTE: For safety you should always use circuit protected cells as per the larger cell I was holding up. It protects against over-discharge, over-voltage, shorts etc.
(BTW, the reference to Lithium Ion Polymer being the same as Lithium Ion is in terms of charging, if that was not clear. The Ion Polymer type have polymer anode material and hence a different construction that allows the small pouch type cells shown in the video, and other thin odd shapes shown toward the end)
EEVblog #176 – Lithium Ion/Polymer Battery Charging Tutorial – [Link]
Jason over at Rip It Apart did a teardown of a Kentli PH5 1.5 V Li-Ion AA battery:
The PCB that holds the 1.5 volt regulator is inside the end cap, with the rest made up of the Li-ion cell itself. Curiously enough, the cell inside is labeled “PE13430 14F16 2.66wh” which is interesting in more than one way. First of all, the rated energy content of the cell is less than what’s on the outside label (2.66 watt-hours versus 2.8), and the cell inside is actually a Li-ion polymer (sometimes called a “Li-Po” cell) type; I was expecting a standard cylindrical cell inside. Unfortunately, my Google-fu was unable to pull up any data on the cell. I might attempt to do a chemistry identification cycle on the cell and see if TI’s battery database can bring something up.
Teardown of Kentli PH5 1.5 V Li-Ion AA battery – [Link]
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]