An application note (PDF) from MAXIM:
The typical specification for lithium coin-cell batteries has been to provide a 10-year battery lifetime in the absence of system power. End users should evaluate the anticipated lifetime in their specific application, especially for those that exceed typical commercial environments or that need to last more than 10 years. This article gives the reader an overview of the major factors affecting the lifetime of an IC that can be powered by either the system power or a lithium battery for a backup supply.
Lithium coin-cell batteries: Predicting an application lifetime - [Link]
by Steve Taranovich @ edn.com:
I have been hearing about so many different and novel techniques for battery charging and cell balancing lately. Designers are working feverishly to optimize cell balancing and battery safety along with improved efficiency. I have been closely watching Sendyne for a while now, ever since the SFP100 was chosen to be one of 2013’s EDN Hot Products and UBM ACE Award finalist in the category of Ultimate Products in Analog ICs. This IC is a current, voltage and temperature measurement solution and can be configured for automatic compensation for resistance dependence of the shunt over temperature with a separate reference design board.
Unique battery pack architecture patented by Sendyne - [Link]
Recent advances of Li-Ion battery technology could be the kick start the faltering electric vehicle market needs for it to go main stream. As well as the fast charge time the new battery can be cycled more than 10,000 times and has a lifespan of 20 years.
The work carried out at NTU Singapore replaces the traditional graphite anode with one made from titanium dioxide, an abundant, cheap and safe material found in soil. It is commonly used as a food additive and in sunscreen lotions. Before the material can be used it is converted into fine nanotubes which allows faster chemical reactions in the cell giving it super fast recharge times.
Li-Ion battery recharges to 70% in 2 mins - [Link]
by Darren Quick @ gizmag.com:
There have been numerous cases of lithium-ion batteries catching fire in everything from mobile phones and laptops to cars and airplanes. While the odds of this occurring are low, the fact that hundreds of millions of lithium-ion batteries are produced and sold every year means the risk is still very real. Researchers at Stanford University have now developed a “smart” lithium-ion battery that would provide users with a warning if it is overheating and likely to burst into flames.
“Smart” lithium-ion battery would warn users if it is going to ignite - [Link]
The Juice4Halt module is a supercapacitor based energy storage. It contains two independent DC/DC converters. The first one is a bidirectional step-up/step-down converter working as the interface between the stable 5V supply rail and the supercapacitor. During charging the converter works in step-down mode and transports energy from the external power supply to the supercapacitor. In case of a power failure the load device (Raspberry Pi or another SBC) is supplied from the supercapacitor via DC/DC converter working in step-up mode.
The second DC/DC converter is a Front-end step-down converter. The only function is converting a high input voltage down to 5.1V for the 5V rail. It is necessary to use the Front-end converter in case of an external power supply.
The Batteryless UPS for the Raspberry Pi - [Link]
by Ben Coxworth @ gizmag.com:
While keeping batteries small and light is definitely a factor with electronic devices in general, it becomes particularly important when dealing with wearable electronics such as smart glasses. With that in mind, Panasonic has just announced its CG-320. Measuring 20 x 3.5 mm, it’s being billed as “the industry’s smallest cylindrical shaped rechargeable Lithium Ion battery.”
The CG-320 weighs 0.6 grams, has a nominal capacity of 13 mAh, a nominal voltage of 3.75 volts, and a maximum charging voltage of 4.2 volts. It also has a stainless steel exterior case, designed to prevent swelling.
Panasonic’s tiny new battery is destined for the wearables market – [Link]
by Colin Jeffrey @ gizmag.com
Researchers working at the University of Missouri (MU) claim to have produced a prototype of a nuclear-powered, water-based battery that is said to be both longer-lasting and more efficient than current battery technologies and may eventually be used as a dependable power supply in vehicles, spacecraft, and other applications where longevity, reliability, and efficiency are paramount.
“Betavoltaics, a battery technology that generates power from radiation, has been studied as an energy source since the 1950s,” said associate professor Jae W. Kwon, of the College of Engineering at MU. “Controlled nuclear technologies are not inherently dangerous. We already have many commercial uses of nuclear technologies in our lives including fire detectors in bedrooms and emergency exit signs in buildings.”
Long-lasting, water-based nuclear battery developed - [Link]
A fine-spot welder is one of the few equipment where building yourself is cheaper than buying. There are already published a lot of DIY spot welders, this one has some unique features:
It can be used in 2 welding applications: opposed and series configuration.
The construction is kept very simple.
Accurate electrode force adjustment.
It has a solid electrode holder, made of a radiator earthing clamp.
An Arduino microcontroller is used to set the weld time accurately.
Creates a double pulse which improves clamping.
The current can be reduced for welding sensitive parts.
DIY battery tab resistance fine-spot welder - [Link]
by pinomelean @ instructables.com:
Lithium based batteries are a versatile way of storing energy; they have one of the highest energy density and specific energy(360 to 900 kJ/kg) among rechargeable batteries.
The downside is that, unlike capacitors or other kinds of batteries, they can not be charged by a regular power supply. They need to be charged up to a specific voltage and with limited current, otherwise they turn into potential incendiary bombs.
And that’s no joke, storing such a high amount of energy in a small and normally tight packaged device can be really dangerous.
Li-ion battery charging guide - [Link]
We all know lithium-ion batteries need careful monitoring to prevent over-charging and ensure cell temperature remains within limits. We all thought we knew the best way to replace the charge as well: trickle charge, take it nice and gentle to keep the cell temperature down and prolong cell life. Turns out we may have got that last one wrong! New findings published in the Nature Materials Journal by a team of researchers at Stanford University indicate that by tweaking the battery design it may be possible to get faster charge/discharge rates and also increase the number of charge cycles.
Better lithium-ion Charging - [Link]