What You Don’t Probably Know About Lithium-ion Cell Phone Batteries

A number of Li-ion batteriesToday, most of the smartphones out there use rechargeable Lithium-ion batteries. They are found not only on cell phones, but on digital cameras, portable music players, and a lot of other electronic gadgets. The major advantages of this type of phone battery are that they have high energy density, high power output, and long lifespan. These advantages make Lithium-ion batteries perfect for portable electronic gadgets. If you ever had confusion as to what these batteries are and what their specifications meant (stuff like mAh, charging time, etc), then let me clarify these details here.

The Basic Chemistry


Look at the image that illustrates the compounds within a typical Lithium-ion battery. I have tried to speak as low-tech chemistry as possible here.

At the base of all these batteries is the basic metal, Lithium (Li). This is a soft, light metal of the alkali metal group, which means this metal is very reactive and difficult to preserve. The optimum reactivity of Lithium makes it perfect among alkali metals (that include sodium, potassium, etc) to form a good battery.

Lithium Cobalt Oxide (LiCoO2) is the most widely used compound on the anode. Cathode (negative electrode) is typically a carbon allotrope. During charging, as you can see, Lithium ions travel to the cathode along with an electron. Once fully charged, it can give out energy through a reverse discharge process illustrated in the picture.

Over-charging and over-discharging tend to create additional irreversible compounds that waste the chemical composition of the battery. It means, a part of the battery becomes pure rock if you continue to overcharge or over-discharge the battery.

Understanding Important Specifications

Lithium-ion battery technology is one of the most advanced and expensive among secondary batteries (those that can be used repeatedly after recharging). It is highly portable due to great energy density, and gives maximum power.

A. Capacity (Ampere-Hour [Ah] or Milli-Ampere-Hour [mAh])

Over time, the cellphone manufacturers have learnt to identify milli-ampere-hour (mAh) as the major measure of battery power. People who are looking for long-lasting efficient cell phone battery look at the mAh rating and talk and standby times given to purchase a device. Let me bust all the myths here. This is the measure that indicates the total charge-bearing capacity of a battery. It doesn’t indicate whether the battery has a long runtime or not.

For instance, 2000 mAh battery is capable of providing 2 ampere of current for 1 hour before fully draining or 0.2 ampere of current for 10 hours before draining completely.

This is also indicated with something called the C-rate of the battery. For instance, if 1C of a battery is 2000 mAh, it means the battery is capable of a maximum of 2000 milli-ampere of current for 1 hour. C/2 of the same battery should be 1000 mAh, and so on.

B. Specific Energy (Wh/kg)

This is an indicator of the power storage capacity of a phone battery. Also known as gravimetric energy density, this measure indicates the size-to-power ratio of a battery. Lithium-ion phone batteries have high specific energy making them perfectly portable. You can usually find the specific energy details on the battery pack itself. This can be also measured in terms of energy density (Wh/L).

C. Specific Power (W/kg)

This indicates the maximum power the battery dissipates from each kilogram of its mass. This is also measured as power density (W/L).

Specific energy and specific power can be balanced to achieve optimum results from a battery, such as high power or high durability at low power. As an analogy, think of a battery as a tank full of water. High specific energy on the battery is analogous to a big tank with small tap, while low specific energy is indicated by smaller tank with bigger tap. You cannot have both high.

Parameters of Typical Lithium-ion Batteries

Check out this table that lists important parameters of generally available Li-ion phone batteries

Specific Energy 110-200 Wh/kg
Voltage 3.7 volts
Temperature range -20° to 60° C
Specific Power 250-730 W/kg
Self discharge Full charge: 20-25 % at 25° C; 35 % around 60° C (monthly estimate) 40 % charge: 4 % at 25° C
Cycles 400 to 1000

Most of the manufacturers of cell phones and tablets equip their devices with batteries of appropriate power in order to have it running long. However, the sheer mAh rating of the battery doesn’t necessarily indicate a longer running battery. You have to look at the power requirement of the device itself. This is usually given within the device’s catalog. This is dependent on the electronics used in the phone.

Usually the power requirement is given within the battery compartment of the device itself.

This is the reason why a high-mAh battery gives less talk-time than a low-mAh one. Here are a few tips to make your phone’s battery run longer.

The Memory Effect

Memory effect is typically found on certain rechargeable batteries; this makes the battery run long or short on charging based on the charging history. Certain Nickel-Cadmium (Ni-Cd) batteries retain less charge and drain faster if users charge them partially.

This has been a concern for owners of new types of batteries such as the Li-ion. However, Li-ion batteries are not affected by memory effect. You only need to charge it fully before the first use.

Tips & Guidelines

1. Do not overcharge the battery as it will lead to unnecessary irreversible chemical reactions, reducing specific energy of the battery.
2. Do not let the battery to drain the charge fully as it will again lead to unnecessary compounds being produced.
3. Dispose of Li-ion batteries very carefully. Either send the batteries back to the company on re-calls, or dispose them off carefully.
4. Do not let the battery operate beyond its mentioned temperature range. Placing the cellphone in direct sunlight or nearby hot equipment could cause dangers like explosion.
5. Li-ion batteries drain their total charge and lifespan over time whether you use it or store it. Hence, it’s not advisable to store them for prolonged periods of time (such as a year or two).


I have tried to give maximum useful information about Li-ion batteries. Most of the information presented here are fairly technical although care has been taken to incorporate laymen. These batteries power most of the smartphones and tablets available in the market today, and I hope people will find this article useful.

[Image credit: Panasonic]

War of the Tablets: Amazon Kindle Fire HD Joins With Two Knights!

Amazon has announced its new tablet, the Kindle Fire HD, in two editions, two days ago. The editions available in this new tablet family include a 7 inch model and an 8.9 inch model. Based on the tone of the announcement, one could tell Amazon is targeting Apple iPad hard. Here in this article, let’s look at the highly ambitious new product from Amazon and see how far it could go into the future.

The Tech Specs

The original Kindle Fire was released by the end of 2011. In this HD version, the tablet has two incarnations; check out their specifications below.

feature Kindle Fire HD 8.9-inch Kindle Fire HD 7-inch
Display LCD IPS 8.9 inches, resolution: 1920×1200; 254ppi LCD IPS 7 inches; resolution: 1280×800
Operating System Android 4.0 Ice Cream Sandwich (with modification) Android 4.0 Ice Cream Sandwich (with modifications)
Processor Dual-core OMAP 4470 1.5 GHz Dual-core OMAP 4460 1.2 GHz
Graphics Chip IT SGX 544 IT SGX 544
Memory 16GB, 32GB 16GB, 32GB, 64GB
Size & Weight 240x160x8.8mm (9.45×6.5×0.35 inches); 567 g (20 oz) 193x137x10.3mm (7.6×5.4×0.4 inches); 395 g (13.9 oz)
Data Package 4G LTE Dual-band, dual-antenna Wi-Fi (MIMO) Dual-band, dual-antenna Wi-Fi (MIMO)
Battery Performance Not yet announced Over 11 hours of various activities
Audio Dual Stereo Speakers with Dolby Digital Plus Dual Stereo Speakers with Dolby Digital Plus

Looking at the specifications, one could easily say that highly ambitious Amazon wants to target both of the segments in the tablet market—high end tablets dominated by Apple iPad and low-end tablets like the Google Nexus 7 or Samsung Galaxy Tab 7.0. The future of the competition remains to be seen.

The Display

Based on the specification, Kindle Fire HD’s display is one of the best available in the market today. Samsung Galaxy Tab, Galaxy Nexus 7, Asus EE Pad Transformer Prime, etc., all have lower if not comparable resolutions with lower ppi ratio.

Besides this, the Fire HD has advanced polarization filter that filters out any glare and gives a really wide viewing angle, thanks to the IPS technology. This makes the LCD IPS display of Kindle Fire HD superior to the displays available on other top-selling tablets. However, Apple iPad’s Retina display is still unmatched in the market.

The Microprocessor

Kindle Fire HD comes with dual-core processors, 1.5 GHz and 1.2 GHz. Although pretty fast, looking at the clock speed, the future belongs to quad-core processors. Google Nexus 7, EE Pad, Sony Xperia, etc., come with quad-core processors. Quad-core processors are there in the smartphone market too, on phones like Samsung Galaxy S3, Galaxy Note 2, HTC One X, etc.

With a dual-core processor, you may soon be compelled to upgrade to better hardware—a point not in favor of Kindle Fire HD.

The Connectivity, Data, & Storage Plans

The data package given by Amazon with Kindle Fire HD 8.9 includes 250 MB of data a month at 4G LTE speeds. The speed given by the tablet exceeds that given by Apple iPad on 4G and Wi-Fi. iPad has a maximum capability of 22 Mbps while Kindle Fire HD goes at 31 Mbps speed with the help of MIMO technology (dual antenna).

wi-fi comparison


In a month, 4 hours of browsing is definitely not going to suffice, and you will end up paying more for the plan.

250MB, if you don’t know the specification, is about half the size of a regular old world CD-ROM, or about 124 emails with attachments, or about 4 hours of browsing. In a month, 4 hours of browsing is definitely not going to suffice, and you will end up paying more for the plan.

Another caveat you get with this tablet is the huge cloud storage option of 20 GB through Amazon Cloud Drive. This is far better than any other cloud storage service out there—Apple iCloud gives only 5 GB, Microsoft SkyDrive comes with 7 GB, and Google Drive offers 5 GB. Besides the standard in-built storage of 16/32/64 GB depending on the model, you get Internet storage of 20 GB. Amazon’s little tablet is not that bad, huh?

The Design

Amazon has always been poor in designing its devices. Do you remember how lame the first Kindle looked? It seemed like Amazon designers had no clue as to what is going on in the design world.

The bad design ideas of Amazon continues with Kindle Fire HD. The tablet looks haven’t seen any bit of innovation. Addition of a synthetic bottom doesn’t make it visually stunning either. However, textured leather cover keeps it protected from scratches and gives good grip. The design is simple and practical, not visually stunning. If you want a really good-looking tablet, take a look at Sony Xperia range or Asus Transformer Prime.

The Price

This is one area that Amazon scores brilliantly. Based on the package chosen, the price of this tablet ranges from 200 to 600 dollars. A 16 GB tablet with all basic necessary features for just 200 dollars is just awesome. And that’s pretty much all you need. If you need higher storage, you can go for the 32 GB version of Fire HD 7. The 8.9 inch version starts at 300 dollars and the LTE version is available for 500 dollars.

The Software

The operating system that runs on the tablet is the previous version of Android, 4.0 Ice Cream Sandwich. Also, it’s not the regular Android you are familiar with. It is a tweaked version developed by Amazon just for this tablet. All of the apps supported by Android are available for download, and the tablet comes pre-packed with several of them including popular games. There is no apparent need to install anything extra when you purchase it.

Jelly Bean is the fastest and smoothest version of Android, and it is a disadvantage that Amazon doesn’t support it yet. We can expect to see firmware updates that will include Jelly Bean for this tablet.

Other Stuff

Other stuff that you get from Kindle Fire HD includes the following:

  • Free books from Kindle owners’ ‘Lending Library’, where over 180,000 titles are available, including bestselling books
  • Amazon Prime members get unlimited streaming of over 25,000 titles including movies and TV shows
  • Easy access to Amazon’s ever-expansive bookstore with over 1.2 million titles and over 400 magazines
  • Music library of over 20 million tracks

Whatever you purchase within these libraries gets stored in your cloud storage of 20 GB, and the browser you use on Kindle Fire HD, Amazon Silk, is fully compatible with the cloud storage given.

Looking at the hardware features given and the price tag, the profit margin of Kindle Fire HD is very slim. This is the reason why Amazon is actively marketing these optional extras which will keep you paying the company while using the product—a very viable marketing method that borders on exploitation of the need for better hardware at affordable prices.


Overall, I would say Amazon has aced this release. Good job, guys! If you want a practical tablet at a very affordable price, and not something that looks stunning, then this tablet is perfect for you. On the other hand, if you don’t want to look geeky, go for some other like Asus Transformer Prime, because it’s in the looks department alone that this tablet doesn’t score.

Is the Future of PCs and Laptops Really At Risk?

If you look at the statistics, people purchased a lot of tablets and smartphones this year. Even the advent of thin laptops—Ultrabooks, and netbooks—hasn’t done much in improving the sales of PC and laptops from last year’s. However, the sale of total number of PC units worldwide has remained almost the same over the last few years. This year also, there is no marked downfall in this. Speculations are afoot in the technology world about the future of PCs and notebooks. Several bloggers have expressed concern about their (PCs and laptops) future. Here’s an analysis on this.

Look at the image below:

pc & laptop sales

Data source: Statista

There are a lot of things to be learnt from this image. Firstly, the number of sales of PCs has remained a constant over the last few years; the number of laptops sold has increased gradually; and there is a regular, expected growth in sales in the handheld PC market dominated by Apple iPad, iPhone, and others. It shows low or no future for Ultrabooks and netbooks (those that have puny hardware).

As soon as tablets entered the market, regular PCs and laptops have been seeing a lot of changes. Their design is getting revamped, the thinness is a factor that is changing, and there is the hardware. Obviously, people demand better hardware and user engagement tools with the new devices. The time has come for mouse and track pad. Now, people are looking for touch and voice input devices. They will lead the changes in PCs and laptops of tomorrow.

Is the PC Business Dead?


The short answer: Hell, No! People need PCs and laptops still. In fact, gamers and people working from home are still going to need a hardware-rich, fast computer at home. There is a different need for each of the device listed above. A PC is for hardcore work—design, gaming, and animation stuff.

A laptop—almost equipped as a PC for hardcore work, with the tradeoff between hardware and mobility. It should obviously have similar hardware features as a PC, and it should perform really well. If you actually need to work in full fledge on the move, then it’s a laptop that you need.

A tablet is for web browsing and entertainment on the move. This is a replacement for netbooks and Ultrabooks, and hell of a good one at that! This is the reason why you see a horrible performance in the sales of netbooks and Ultrabooks.

Although thin notebooks like Apple MacBook Air and Toshiba Satellite are very popular, the reason behind it is different. MacBook Air can never be compared to a tablet. It’s a full-fledged, regular laptop but with a lot of mobility. MacBook Pro on the other hand can be compared to a full-fledged PC. This is the reason why they are still selling hot.

On the other hand, people who already have an iPad don’t really need a netbook with low features like 1.5 GHz processor speed and 1 GB RAM. Such a netbook will never be a replacement for iPad, and it will never be a hit in the laptop market either.

Each of these devices has its own intended use and hence another device cannot replace it. And by extension, it will not lose its market share. Another aspect to consider is the advancement of netbooks like the Google Chromebook. They are thin clients that work with the help of a cloud computing system. In such cases, the hardware needn’t be great for the PC to give great performance. However, in such cases also, the bottleneck is the network speed. And such a netbook will still not pose a threat to the tablet market as a tablet is great as a thin client.

However, the future of PC will see a lot of advancements inspired by tablets and smartphones. That’s what we need to look out for in the coming days. In short, PCs and thin laptops will stay on while Ultrabooks and netbooks with hardware similar to a tablet will not stay in the market.

How to Install Incompatible Android Apps on Your Phone?

android unlock

In Google Play store, there are about half a million applications, paid and free. As the owner of an Android phone, you may have a number of preinstalled apps and some apps that you installed. Some of these preinstalled apps are collectively known as bloatware.

I don’t know about you, but on my Android phone I would want to remove unnecessary bloatware and install some advanced apps most of which are incompatible with the phone. This is a procedure that requires root level access to your Android device as well as editing some of the important system files. In this article, let’s see how this is done.

In order to make your Android device compatible with all the apps out there, you should have your device ‘rooted’. This is a process that could void its warranty and render it inoperable. If you are an advanced user, you may already know the side effects of rooting and flashing new firmware to your device—you could brick it! (that is turning it into a glittering black brick, literally).

What Is Rooting?


Android runs on Linux kernel; if you know or have used Linux, you know the administrator account is known as ‘root’. Linux, unlike Windows, doesn’t provide you with system level access. This is one of the reasons that make Linux highly secure.

When you get root access on Linux or Android, it essentially renders the device insecure. This is one of the reasons why Google Wallet gives you an alert when you try to use it on a rooted device.

Also, you should know if your phone is capable of handling rooting process. Phones like HTC One X, One S, Desire, Inspire 4G, Evo 4G, Samsung Galaxy Note, Galaxy S2, S3, Galaxy Nexus, etc., have all been found to root successfully. For specific information about rooting and to see if your device supports it, go to XDA-Developers forum, CynogenMod Wiki, or RootzWiki. It goes without saying that you should back up your phone’s important data before proceeding.

After rooting has been done, install an app to explore and edit files on Android (similar to Explorer on Windows)—ES File Explorer is the popular one used by power users.

ES explorer


You have to edit the bulild.prop file in order to make your device compatible with incompatible apps. Build.prop as you know is like a registry to Android, and editing it without proper knowledge is not going to do anything good to your device. Make sure you follow the instructions carefully and research on Android support forums and blogs before attempting it on your phone.

Edit Build.prop and Set Device Name


Within the ES File Explorer Settings, put a check to ‘Root Explorer’ and ‘Mount File System’.

Browse to build.prop file, located within the System directory. This file identifies your device to Google Play store. Hence, editing it and changing the device name would actually fool the app store thus enabling your device to download the necessary app. Back it up first and then open it within ES Explorer. If it doesn’t open properly, press on the icon longer and select ‘Open As’; select text and open with ES Note Editor.

editing build.prop

Within this text file, you will see ‘ro.product.model’ field and ‘ro.product.manufacturer’ fields. Change them to whatever you would like to use in order to change the identity of the phone. For example:

If you have Nexus S and want to change to HTC One X, then change it in this way:

Ro.product.model=One X

Save the file and you are done!

In order to actually test the app, however, you have to restart the device. Sometimes, you have to also clear the cached information stored by Google Play store on your device—go to Google Play app ‘Manage Applications’ page and clear the offline storage from here.

Although this is a workaround to get apps running on your device, the system doesn’t impart an actual compatibility, does it? So, you can’t expect any app to run on your device. If the app is literally not compatible, there is no way you can get it to work.