By Sean Michael Ragan:
The Joule Thief (Wikipedia) is a well-known “instant gratification” hobby circuit that uses just a handful of components to pull off a pretty impressive parlor trick — using a single 1.5V battery, the Joule Thief can light a high-voltage blue or white LED that normally requires 3.5V or greater to turn on. Even more impressive, it can do so using a battery that is so drained of energy as to be counted “dead” for almost all other purposes. I have not measured this value myself, but it is commonly claimed that a Joule Thief can light a white LED from a battery with an open-circuit voltage as low as 0.6.
Bring “dead” batteries back to life with a toroid and the Joule Thief circuit. - [Link]
1,6V rechargeable batteries experience “rebirth” and bring several advantages in comparison to 1,2V NiCd accumulators
Experts in electrotechnics might say, that these are a long-time known batteries invented already by Edison thus being no novelty at all. That´s true but in contrast to older tyes is in technological advance of electrolyte and electrodes so as to reach a substantially higher lifetime that few decades ago.
So what´s interesting about these rechargeable batteries? By one sentence, NiZn cell has an output voltage of approx. 1.65V, what´s about 0.4V more than NiMH/ NiCd cells.
At the same time they´re able to provide a high current, similarly like NiCd/ NiMH cells, that´s why they´re also usable in devices with high current demands (conductivity of Zinc is about 15% than Cd). NiZn cells are easily recyclable and they´re very environmentally friendly. Another benefits:
- energy density of NiZn cells is about a third higher than that of NiCd cells (Wh/kg and also Wh/liter).
- higher voltage (1,6-1,8V) enables to reach a higher voltage of „battery-packs“ with a lower count of cells
- lifetime is comparable with NiCd cells
- no memory effect, trouble-free recharge to 100%
- flat discharging characteristics, average voltage aprox. 1,6-1,7V
It is recommended to recharge NiZn cells by C/4 to 1C current (i.e. for example 500 mA to 2000 mA for a 2000mAh cell) while observing a max. voltage of 1.9V/ cell. It´s not recommended to leave cells at a so called “trickle charging” as overcharging might decrease lifetime of cells. Naturally, like in case of almost all rechargeable batteries, the highest lifetime can be reached at operation on a partial discharge (not to a deep discharge). It´s worth to say, that NiZn are not an ideal replacement into devices with a very small power consumption ( e-g- remote controllers), where still win primary alkaline cells.
In our offer can be found NiZn cells themselves: 4AA2500mWh1.6V BP4 and 4AAA900mWh1.6V BP4 as well as a set – charger + cells (4xAA+4xAAA) NizN Charger + Accu. This charger charges by 500 mA current (AA/AAA) and monitors each slot individually. During recharging a LED at agiven slot blinks slowly (1x/s) and after finishing of recharge it shines continuously. In case of a faulty cell it blinks quickly (4x/s).
NiZn rechargeable batteries – when Nickel and Zinc create a strong pair - [Link]
By Colin Jeffrey:
We literally live in a wired world, with wires snaking hither and yon transmitting electricity and data. Many are visible, while many more are hidden in the walls of buildings, the panels of cars, and the fuselage of aircraft. Now, imagine; what if we were able to turn each and every one of these into a battery that not only transmitted electricity but stored it too? Well, two researchers from the University of Central Florida (UCF) imagined that too, and came up with a way to use nano-technology to make wires with supercapacitance that may eventually also double as batteries.
Researchers create flexible wires that could double as batteries - [Link]
Tutorial – MicroLipo and MiniLipo Battery Chargers @ The Adafruit Learning System.
Sooner or later you’ll need to cut the cord…the power cord! Untether your electronic project from the tyranny of the wall adapter and take it out into the world. That’s where batteries come in, and you may have been seduced by the high power density, large current capabilites and recharge-ability of Lithium Polymer or Lithium Ion batteries. These battery chemistries have quickly become the most popular rechargeable batteries in consumer products, powering everything from keychain mp3 players to huge laptops.
Tutorial – MicroLipo and MiniLipo Battery Chargers - [Link]
LiPo Booster –
LiPo Booster is a breadboard-friendly boost converter board based on the TPS61230 IC from Texas Instrument. It has an output voltage of 5V, and is designed to be used with a single cell LiPo battery.
For normal and half size breadboards, the LiPo Booster can be plugged into the power rails without blocking the vertical 5-pin strips. It can also be used with a tiny breadboard or breadboard of any sizes as shown below.
LiPo Booster - [Link]
A startup Japanese company called Power Japan Plus have announced a new type of rechargeable battery which they claim is a significant improvement compared to LiIon batteries. The battery was developed at the department of applied chemistry at the Kyushu University in Japan.
The press release suggests that vehicles equipped with the battery would have a 300 mile range, indicating a better energy density than LiIon batteries. They also claim that the battery can be recharged twenty times faster than LiIon and can be cycled more than 3000 times without loss of capacity.
If that doesn’t tick enough boxes they also go on to say that the battery does not produce any significant temperature rise during operation so there is no need for additional cooling and no risk of thermal runaway. Details of the design are sketchy but they state that the only active material used in the battery is carbon, making it cheap to manufacture. The battery is described as using an organic electrolyte where positively charged lithium ions flow to the anode and negatively charged anions flow to the cathode, which would suggest other elements are also at play. The design is said to be 100 % recyclable. Power Japan Plus are currently focussing their research on a new type of carbon-complex battery made entirely from organic carbon.
Is Dual Carbon the Way Forward? - [Link]
By Tahar Allag, Wenjia Liu:
Cell phones are a good example of how functionality and performance have both increased significantly in portable devices over the last few decades. They have become more complex and can do many basic tasks as well as any computer. The extra functionality that has transitioned the smartphone from a phone-call-only device to a multipurpose portable device, which makes it more power hungry than ever before.
The internal battery pack is the main source of storing and delivering power to portable-device circuitry. Batterycharger ICs are responsible for charging the battery pack safely and efficiently. They must also control the power delivery to the system to maintain normal operation while plugged in to wall power. The battery pack is required to store a large amount of energy and be charged in a short amount of time without sacrificing weight and volume. The increased charge and discharge currents, as well as the smaller physical size, make the packs vulnerable to physical and thermal stresses. Therefore, battery chargers are no longer required to perform just as a simple standalone charger
AppNote: Battery charging considerations for high-power portabledevices - [Link]
Designers of rechargeable battery-powered equipment want a charger that minimizes charge time with maximum charge current by maximizing the power taken from the supply without collapsing the supply. Resistances between the supply and the battery present a challenge. This article explains how to design the charging circuit to achieve the maximum power from the adapter despite the undesired resistances between the supply and battery.
AppNote: Extract maximum power from the supply when charging a battery - [Link]
Organic LED, microprocessor controlled, intelligent energy source for all of your electronic devices.
Legion is a portable energy source with a built-in Organic LED display coupled with a microprocessor. It can charge any USB powered electronic devices. Unlike a traditional portable battery where you’re left in the dark about the state of charge of your battery, Legion learns how you use your electronic devices and displays precisely how much more time (day:hours:minutes) you have remaining until you run out of power. Legion uses premium grade Lithium Polymer batteries designed to maximize your energy density while packing it into the smallest area possible. Legion is proudly designed in Silicon Valley, California.
LeGion Halves Phone Charge Times – [Link]
Fully Programmable Solar BMS ( Battery Management System ) Learn to program microcontrollers and HW design video tutorials Open Source:
This Battery Management System development board is designed to work with any type of rechargeable Lithium batteries and supercapacitors thanks to fully user programmable parameters.
Whenever you need to use a rechargeable lithium battery you will also require a BMS. Most small device have them integrated like the battery from your laptop, cellphone or cordless power tools (if they use Lithium). Same is true for supercapacitors (EDLC).
Open Source Programmable Solar BMS Li-ion, LiFePO4 dev board - [Link]