Friday, July 31, 2009

Rechargeable Battery Care


Nowadays, rechargeable batteries is a must for our gadgets and is commonly used in mobile phones, notebooks and home electrical appliances. Very often we take them for granted and provide the wrong battery care! Not taking care of your batteries properly not only shorten their lifespan dramatically, but can also cause harm and damage to you and your surroundings. Below, I would cover two commonly used battery types in our household, Nickel-Cadmium (NiCd) and Lithium-Ion (Li-ion).

Nickel Cadmium (NiCd)

Charging / Discharging

NiCd batteries suffer from memory effect, if they are are recharged and discharged to the same level of charge regularly. This is usually obvious when the battery voltage suddenly drops dramatically. However, the capacity is not reduced substantially. To recover this lost capacity, perform a deep or full discharge to INDIVIDUAL CELLS once in a while by using the battery until its fully discharged (or even better, with your battery charger if it came with a deep discharge function). It is not recommended to discharge your battery pack as a whole, as some cells may be discharged earlier, and this will result in a cell reversal charge condition. If you do not have any of these dischargers at your disposal, just use your batteries with an electrical appliance until its near dead flat for the FIRST time (If you have a voltmeter, stop the discharging sequence when the battery pack voltage drops to 1.0 V). After that, recharge it like normal. Individual cells can be discharged to zero voltage without harm.

Do not perform deep discharge too often as it will shorten the lifespan of the battery. (Once a month should be fine)


Typically, 1000 charge cycles before its capacity drops below half of its original capacity.


If not used, the battery should be discharged to maximum 40% of its capacity and store it in a cool dry environment.

Other precaution measures

Do not mix old and new batteries together. Old batteries loses its capacity quicker and could be damaged due to cell reversal charging. It could also cause damage as hydrogen gas is produced when this occurs.

Lithium Ion (Li-Ion)

Charging / Discharging

Unlike NiCd batteries, Li-Ion batteries do not suffer from memory effect. In fact, they should be charged as often and regularly as much as possible and should NOT be fully discharged. Discharging it fully will damage the battery (below 2.4V) permanently. Good Li-Ion batteries will always self discharge slowly from time to time, since it has an internal safety circuit that will prevent a “dead” battery to be charged (recharging a dead Li-Ion battery can be very dangerous). Since its charging process is a non linear process, its therefore dangerous to charge a Li-Ion battery without any monitoring mechanism. The charging sequence usually consist of 3 parts as quoted from Wikipedia:

Part 1. Apply charging current limit until volt limit per cell is reached.

Part 2. Apply maximum volt per cell limit until the current declines below 0.03C

Part 3. Periodically apply a top-off charge about once per 500 hours.

Some devices may have optimization charging mode when you charge the battery “in-house” together with the device turned on. It is recommended that you turn your device on while charging so that the device is able to monitor and prevent overcharging from occurring. Most dedicated chargers have this circuitry as well. If you are to charge it unmonitored, do not charge it for more than 3 hours or manufacturer specified time.


Typically, 1200 charge cycles. However, it is important to note that Li-Ion batteries age with time, even if not used.


Charge/Discharge it to 40% and store in a cool place to reduce the aging effects. Do not store a Li-Ion battery at 100% charged.

Other precaution measure

Li-Ion batteries are sensitive to heat. You should consider removing the battery from your equipment like notebook if you are going to connect it to a direct power supply for long hours. You should also buy Li-Ion batteries only when you need it due to its aging effect.

Sources – BatteryUniversity, Wikipedia

Tuesday, July 28, 2009

Deposit Cheques at Home – Using a Scanner


It seems that we can deposit cheques from the comfort of our own home with just a scanner and internet connection soon, at least for the US-based residents. USAA, a financial service company which only serve people and family members who served in the US military is currently providing this service called “Deposit@Home”. This is specially convenient for those who travel often and have no time to go to the bank to drop in the cheque. You can check out the demo video at this link . There is report that Florida-based EverBank is about to start offering this service as well in the next few weeks.

I have no idea on whether this will actually be implemented in Malaysia. Luckily for us, the queue for cheque deposit aren’t usually very long.


Monday, July 20, 2009

Fujifilm 3D Camera – Taking photos in 3D!


Two decades ago, Fujifilm developed the world’s first fully digital camera. Later this year, Fujifilm will unveil another new camera technology – the world’s first 3D digital camera.

FinePix Real 3D System (its tentative name at the current time of blogging), Fujifilm’s new gadget will hopefully allow it to be ahead of the competition in the already saturated consumer market. This will definitely rejuvenate the saturated digital camera market as the limits on the megapixels, optical zoom as well as as other features such as face detection and anti-shake seems to be common for all digital cameras to date.

I did not have the opportunity to have a look at the actual prototype of Fujifilm’s new camera. Based on reading other articles and sources, its quite pleasant to know that the prototype was not much bigger or heavier than the current digital cameras in the market. One obvious difference in Fujifilm’s 10 megapixel camera is that it uses two lenses instead of one, spaced from each other about the same distance between the two human eyes. This allows the camera to shoot two photos from different angles as viewed by each individual human eyes of the same scene. The camera then intelligently presents the two images discretely to the right and left eye of the viewer, thus resulting in a stereoscopic image (this two images help provides the depth lacking in 2D photos). For 3D prints, a plastic overlay is also needed to act as a lens to provide the depth effect.

It would be interesting to see how much would this print cost and will user be able to print these photos at home without much cost.


Wednesday, July 8, 2009

Google’s Operating System - Google Chrome OS


Google finally announced it. I bet most of us were half-expecting it will come to this day, so I was not surprised by this announcement. Google announced on their blog that they were working on a new project called “Google Chrome Operating System”.

Basically, the OS is an open source (like Chromium project for Chrome), lightweight operating system which targets the netbook segment. The codes will be available by the later part of the year, and consumers will be able to use it by second half of 2010. Sounds good?

The netbook segment current represents quite an interesting dilemma. Being a stripped down version of the notebook with less power, the operating system has to be able to do the same tasks as a notebook with less brawl. At least basic tasks such as web surfing, playing music, typing emails and maybe some simple flash games. Currently, most netbooks’ operating systems are Windows XP (already obsolete), Windows Vista (soon to be obsolete when Win 7 comes by), Ubuntu / Linux and the upcoming Windows 7. Among the choices that we currently have, Ubuntu and Windows 7 seem to be the only viable choices out there as Vista will just crawl so bad and Windows XP will be losing official support very very soon in the next few years.

So, why would users use Google Chrome OS over the other OS veterans? Because its free? No. Because its open source? No. If there’s one thing Google can learn over problems which plague other OS, that is security. Google has managed to developed a secure browser with its Sandbox feature, it can do it with the OS version. They should have enough to learn to rectify and prevent security issues that could potentially plague an operating system, and they were pretty good at that with the browser so far.

Since Google made it very clear that the OS will be a web-centric OS, most of your applications will be on the web. That probably means a tighter integration with Google Apps (Gmail, Docs etc.). This will improve the performance of your netbook as the load will not be as heavy as a normal Windows or Ubuntu netbook. Perhaps we don’t even need to scramble for device drivers again as we can search and install driver through the “cloud” in Google’s enormous networks (installing drivers were often a bane when it comes to installing Windows on a fresh new PC). These will definitely make users happier.

Stay tune for more updates about Google’s OS. The architecture of this new OS will be interesting, especially on the security aspect.

By the way, if you din’t notice, Gmail has shed its beta label already =).

Microsoft, be prepared, be very prepared.


Tuesday, July 7, 2009

Microsoft Research Paper : CIBAI


If you’re from Malaysia or Singapore, you’re probably going to laugh your head off and going “WTF”. After that, please proceed below on what the research paper is about. For those peeps who don’t understand the fuss about the “Cibai”, I will explain at the end of this post.

“Class Invariants By Abstract Interpretation” , or CIBAI for short was a paper submitted by a researcher by the name of Francesco Logozzo. According to the abstract, Cibai is a generic static analyzer based on abstraction interpretation for modular analysis and verificiation of Java classes. A popular approach that’s frequently used validate program code is unit testing (eg. JUnit). Cibai was proposed to verify and test Java classes in a different way, and its results showed a higher level of automation and precision while having comparable performance. I have yet to finish reading through the paper, perhaps I’ll update this post later if I deem necessary. In fact this paper may be interesting for Java Developers to increase the quality of their codes.

Did you know that Cibai is also a word in Hokkein? A very "crude" one.

Cibai means female’s vagina in hokkien. It is also a commonly used vulgar word as it is the equivalent to the F word commonly used in English. Imagine a conference paper submitted by that name and its being read and heard via loudspeakers @_@.

This was just a coincidence, albeit a very rare random case. Please be careful when naming your products or papers. Google it before you actually put those words to paper.

Microsoft Research : Cibai

Hokkien Definition of Cibai

Monday, July 6, 2009

Norton AV and Internet Security 2010 beta is out


A few weeks after MSE beta was announced, now its Symantec’s turn with their latest Norton Internet Security 2010 and Norton Antivirus Beta. I was never a fan a Norton’s AV because of their huge memory footprint in previous versions. I heard that the 2009 version improved on this aspect but I was already “converted” to be a loyal user of Kaspersky, so I doubt I will ever go back to using Norton ever again. Don’t let this hinder you to test drive the beta though if you’re interested.

To the folks who want to try out the beta, you can grab it from their Beta Center at

Bear in mind, I have no idea how long the beta will last before it expires. I heard its about 2 weeks to a month, but I’m not able to find any details on this. Just keep this in mind if you decide to test drive it. Do let me know by posting a comment in this thread if you know.

And yes, it works with Windows 7.

Friday, July 3, 2009

Charging Your Mobile Phone Wirelessly


“Hello? Yes Ma, I want to tell you that I will be … *beep *beep *beep, dead battery.”

How many times have we encountered this surprisingly common scenario? As for me, I always end up searching for the nearest un-vandalized telephone booth. Sometimes I wish my phone came with solar cells so that I can recharge by leaving it under the sun or some portable battery mobile phone charger (I did see one which uses a 9V battery to charge, but its only for old Nokia phones).

Nokia did it. You can charge your phone anywhere, everywhere, even at night! How?

They developed a new prototype charging system, which collects the ambient and stray radio waves such as TV, radio and even mobile phone signals and convert them into electricity. The power currently harvested by the prototype is still quite far from the required power in order to keep the phone in standby indefinitely though, for now. Nevertheless, this is a good sign that it still has great potential.

---Geek mode started! Proceed if you like to know more ---

This conversion of wireless energy into an electrical form was actually demonstrated before by Nikon Tesla in 1893, in his attempt to build an intercontinental transmission tower to send power wirelessly across the Atlantic Ocean. Nokia’s version is a very simple version of it, with just a wide-band antenna and two circuits. The antenna and receiver circuits harvest signals from 500 MHZ to 10 GHZ and convert these EMG waves into electrical current and feed it into the second circuit. The feeder circuit will then feed the current to charge the battery of the mobile phone.

There is a problem though, these circuits have to use less power (power loss + consumption) compared to the amount of power harvested from the EMG waves. Currently, the amount that can be harvested is up to 5 mW. 20 mW is needed in order to charge the battery of the phone enough to keep it on standby mode indefinitely without doing any phone functions. However, for a meaningful charge, a power of 50 mW is needed.

--- Geek Mode End ---

Nokia expects these phones to be out in three to five years time.

By the way, Palm Pre can be charged wirelessly via electromagnetic induction through its “Touchstone”. However, this still requires you to “dock” it to charge it.


Wednesday, July 1, 2009

The Death of AC Adapters in the Future?


Recently, Fujitsu Labs has announced that the company has developed a new type of energy-saving transistor, which would eliminate the need of AC Adapters used for notebooks.

This new type of transistor made of gallium nitride can reduce losses that are lost in current power supply units of computers, notebooks and other devices to up to one-third or less of the current level. Also, with the smaller size of this new transistor, the power supply unit can thus be integrated into main body of the notebook itself. This will be handy, all you need is just a power cable (hopefully a generalized cable can be used so that we can use one cable for all different brand of notebooks) direct from your wall socket. This would also help to eliminate possible fire hazards, as I began to doubt the reliability of notebook AC Adapters recently due to frequent report of burnt adapters nowadays.

This transistor is expected to be around for practical application in 2011.