Lithium-Sulfur battery cells, the upcoming replacement for Lithium-Ion

Lithium-ion batteries, the current battery technology used in smartphones, has a high specific energy (energy per weight) but has a few drawbacks. Let's take a closer look and compare both technologies.

The main issue with Li-ion is that is requires lithium dissolved in extremely volatile and flammable organic solvents; e.g. dimethoxyethane which has a low flash point -2 °C (28 °F), the temperature at which a volatile substance can evaporate and form an ignitable mixture in air. This makes them extremely dangerous when the charging circuits malfunction and fail to protect the battery from overcharging, and consequently overheating. We have seen some scary stories in the recent past with people waking up to their phone bursting into flames while they were charging overnight, and the battery fires in the new Boeing 787 Li-ion battery packs. So obviously there is need for development into a safer battery composition with similar or better energy capacities.

Recently I did some research into the developing Lithium-Sulfur battery, with extremely promising specifications at the present time better than Li-ion. Li-S is extremely light weight due to the use of sulfur instead of ionic liquids, additionally sulfur is much cheaper to produce than ionic liquids. Despite frequent headlines about new battery compositions with potentially high capacities, Li-S is actually in the production stages and no longer just a concept.  

The chemistry behind Li-S is essentially the lithium gets plated onto the anode when charging and poly-sulfides are reduced and coat the anode when discharging, compared to the use of intercalated anode and cathode plates in Li-ion. This is the main factor which gives Li-S potential to be a battery composition with an extremely high specific energy. The different chemistry also allows the use of much less volatile solvents such as polyethylene glycols (flash point up to 287 °C/548 °F).

The degradation of Li-S is different to Li-ion but is also susceptible to an increased rate of degradation at high temperatures. There are unwanted side reactions that can take place, but are reversible until they dissolve into the solvent. Luckily sulfide compounds are relatively insoluble in electrolyte solutions but any increase in temperature will increase their solubility, so batteries need to be well regulated to prevent rapid charging and discharging.

Manufacturers are beginning to pour money into research and development for Li-S as there are a lot of factors which can be significantly improved, from something as simple milling smaller sulfur and carbon particles to something more difficult like developing a better solvent to improve battery capacity and reduce degradation. (Carbon nanotubes/nanofibres are used as a conductor due to sulfur’s poor electroconductivity, and they are still quite expensive to produce.)

I've put a graph at the top to compare rechargeable battery technology in the past with Li-S. Now, time to see which OEM will be implementing Li-S first.

TL;DR Lithium-Sulfur batteries are capable of having a higher wattage per weight than Lithium-ion whilst being both safer to the consumer and cheaper to manufacture.

Puncture test comparison

Short circuit test comparison

This article is also to be found on its author's personal blog.

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What’s new in 2014 - a year of technology

What’s new in 2014...

Have we reached the point of diminishing returns?

With 2013 now behind us, I want to look back upon the past year and analyse the technology we saw, as well as speculate upon what we are likely to see this year. I think 2013 was a relatively disappointing year for mobile phones, however 2014 looks more promising.

Displays of 2013

For many, 2013 will be known as ‘the year of 1080p screens’, as almost every flagship model incorporated these high resolution displays at the cost of battery life and overall fluidity. This meant that overall performance seemed stagnated in general operations, with the HTC One X rarely under performing to the HTC One, except in gaming performance. 

However, the benefits of a 1080p screen as compared to a lower resolution are noticeable to most and definitely offer an improved experience, resulting in less eyestrain and the ability to browse the web more elegantly. Of course, not every 1080p screen is equal. We saw improvements in colour reproduction, brightness and touch sensitivity in 2013, as well as advancements in technologies like AMOLED. With Apple retaining it’s sub-720p display on the iPhone 5S, many agreed that this was subpar and that this will need to be improved upon in 2014, else market share will suffer. The Xperia Z was widely criticised for its poor viewing angles, resulting in poor sales despite otherwise quality hardware. This shows the great importance of a quality screen in the current market. Display size in 2013 saw a huge increase from previous years. In 2010 for instance, the display of the iPhone 4 at 3.5 inches was considered large. By 2011, the Galaxy S2 had upped this to a 4.2” screen, and in 2012 the Galaxy S3 was released with an even larger 4.8” screen. 2013 can be known as the ‘phablet year’, with a large number of phones released with a screen size larger than 5 inches. This is a trend on the rise and I believe that in 2014, any screen with a size less than 5” will be regarded as ‘small’.

Displays of 2014

In 2014, many smartphones are rumoured to be incorporating WQHD screens, with a resolution of 2560 x 1440. This is a resolution higher than most laptops on the market and seems to be overkill for a screen so small. The benefits of 1080p were visible, but with another resolution jump, the impacts on performance and battery life don't seem justified. A 1080p screen seems pin sharp and any higher may truly be more pixels than the eye can distinguish. This year in the television industry, there will be a major focus on OLED displays, due to their superior black levels, brighter whites and fast refresh rates. However, in the mobile industry I believe that LCD will still dominate, due to a cheaper cost and advancing technologies allowing for higher resolutions on a thinner screen. Only Samsung and Nokia are currently utilising OLED screens and while they are praised for their colour saturation and black levels, many argue that the colour is not reproduced accurately and that the Pentile matrix of Samsung’s latest screens means that they are not at true 1080p. OLED displays also commonly have a tint, resulting in darker, less pure whites. The S4 for instance has a clear blue/green tint when compared to the HTC One which uses an LCD. To conclude, I believe that in 2014, 1080p will be the standard resolution for most phones, with a few rising to 2560 x 1440. The benefits of this are yet to be determined. Screen sizes in 2014 will be 5” or above for flagship devices, with the Galaxy Note series increasing to around 5.9”.

Batteries of 2013

In any portable device, battery life is a major concern and in mobile phones, this has an even greater importance. Over the past few years, battery life hasn't really improved. This isn't due to the non advancement of battery technology, but more due to the increased power usage of components in phones, with the latest screens and SoCs using more power than they did a couple of years ago. This creates the illusion that the batteries used are exactly the same as those used in 2011, while really they are advancing at a steady pace. For example, the HTC Desire (was one of the highest rated phones of 2010) utilised a 1400 MaH battery, while the HTC One uses a 2300 MaH battery. With 900 MaH extra capacity, the HTC One should have greatly improved battery life, while in reality it is not much different. This is because of the more power hungry components. One anomaly in 2013 was the iPhone 5S, which uses a 1570 MaH battery. This is far lower than other flagship phones on the market yet still manages to provide a days usage. This is due to the less demanding processor, as well as software optimisation in the closed Apple ecosystem. The drawback of current batteries is that they are still too large. To include a large 3,200 MaH battery such as the one found in the Galaxy Note 3 requires… you guessed it, a phone the size of a Galaxy Note 3. This means that phones cannot continue to get much thinner with the current generation of batteries, else battery life will suffer. 

Batteries of 2014

Phones released in 2014 will have a healthy bump in MaH as compared to 2013, however we shouldn't expect to see a noticeable difference in usage times, due to the impending release of WQHD displays and even beefier processors. I believe MaH will hover around the 3000 MaH range for flagships this year, with phablets potentially pushing towards the 4000 MaH mark. A day of solid usage can be expected. One thing that split opinions in 2013 was the issue of the removable battery. It was argued that it was required in order to switch batteries when the original had lost charge through age and that non-inclusion was a type of planned obsolescence. Others argued that many don’t keep a phone for longer than 2 years and that in this time, a battery would still maintain at least 75% of the original charge. Personally, I find a removable battery useless for my needs and think that the design changes required to incorporate one are detrimental to the looks of the phone. I would take a well built solid unibody phone over one with a removable flimsy back cover any-day. In fact, a removable battery just seems so old school, Nokia 3310 anyone? In 2014, unibody phones will be standard.

Cameras of 2013

In 2013, DSLR sales suffered. This was mainly due to the increasingly good picture quality on mobile phones. While professional photographers can’t sell their professional equipment yet, for many users a mobile phone camera is more than sufficient. Cameras in 2013 saw resolutions as high as 13 megapixels, while some manufacturers decided to go in the other direction: reducing the number pixels in return for better low light photos and less noise. There is split opinion on the effectiveness of this strategy. Personally I prefer the photos taken from the standard 8 megapixel HTC One X camera than those taken from a 4 megapixel HTC One, with 2um pixels (‘Ultrapixels’). The 13 megapixel camera of the Galaxy S4 can take some great shots, however colours are too processed and noise is an issue with such a small sensor. Overall, I think that the greatest camera of 2013 was that on the iPhone 5S, which features an 8 megapixel shooter with larger pixels like seen on the HTC One. This allows for good sharpness while also reducing noise. Mobile phone cameras now have a number of quality features that even DSLRs can’t match, such as high quality slow motion video, 4K video recording and options to remove unwanted objects from an image with a simple tap. Shooting speeds also dramatically increased from 2012, with speeds of up to 10 photos per second. 

Cameras of 2014

I think that this larger pixel technology will be seen more often in 2014, with HTC and Apple likely to continue the trend. However, I wouldn’t expect to see Samsung attempt this. In fact, a 16 megapixel camera on the Galaxy S5 wouldn't surprise me. HTC will likely release an 8 megapixel ultrapixel camera, while Apple could either remain at 8 megapixel or jump to 13. Expect to see an improvement in editing options this year, as well as the rise of 4K video. Optical image stabilisation will also be included in most of the flagship devices, as this removes camera shake from photos, meaning that photos taken with a non steady hand or on the move won’t be blurred.

An 8MP camera with 2um pixels will require a phone to be 18mm thick at the camera site; not sure if any manufacturer will go there. Check out this article for more details - Cameras in Phones - what do we really need?

Processors of 2013

Qualcomm dominated 2013 with their Snapdragon range. In fact, every Android flagship of 2013 used a variant of a Snapdragon processor, with the exception of the 8-Core Exynos processor used in certain non-European models of the Galaxy S4. The first 64 bit mobile processor came in 2013 with the launch of the Apple A7. This offers certain improvements, such as a 25% performance increase just for apps that are compiled in 64bit, as well as being able to handle more RAM for the future. Processors have reached the stage where most activities on a device are fluid and apps launch very quickly. The GPU on a SoC matters more, as this determines gaming quality and can affect the FPS of general device navigation and scrolling. The Snapdragon 800 and Apple A7 are very fast CPUs. An interesting point is that while all Android flagships used a quad core CPU in 2013, Apple only used a dual core. The dual core A7 even outperforms the quad core Snapdragon 800. This is due to the ARMv8 internals of the chip. Every processor currently used in Android devices is ARMv7 or less. ARMv8 offers a number of improvements including 64 bit support, faster handling of encryption and an increased number of registers.

Processors of 2014

Currently, the Snapdragon 805 is expected to be released in the first quarter of 2014. This is known to have a maximum clock speed of 2.5GHz and an Adreno 420 GPU. However, it is still based on ARMv7, meaning it is 32 bit. This means that Qualcomm is actively slowing down the development of ARMv8, even with ARMv7 currently at the end of its cycle. I expect to see an ARMv8 processor from Qualcomm towards the end of 2014. Processors will remain at quad-core for the most part and I expect Apple to keep its dual core set up which has proven itself as a great performer.

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More details about the HTC M8

In a few months we'll most likely see new high-end device from HTC. Some of the current rumours were true, but here comes much more details you've never heard before!

Device will be named HTC One+ (codename: HTC M8) and it won't have any capacitive buttons. No more "home" or "back" buttons we get used to with the HTC One (HTC M7). Camera is probably a 6MP or 8MP module, of course with the UltraPixel™ technology and probably the new HTC ImageChip™ 3. Current rumours about double lens (for low and high lighting) might be true as well. Battery capacity is much bigger now - 2900 mAh instead of 2300 mAh in the HTC One. With just a slightly bigger screen in the HTC One+ (5") versus HTC One (4,7") we can expect much better battery life.

Chipset (SoC) is very likely to be Snapdragon 805 (instead of 800). This is a very good news because Snapdragon 800 is already quite an "old" chipset. The only problem is the drivers development by Qualcomm. Let's hope that won't stop HTC from replacing S800 with the S805.

In contrast to the HTC One, the One+ will have removable micoSD card. The non-removable microSD card in the HTC One was a source of a lot of critics from Android fans. Hopefully the design of the HTC M8 won't suffer from that.

HTC One+ will be equipped with the newest HTC Sense™ 6.0 and Android KitKat.

So what do you think? I'm already very excited and really can't wait for the HTC One successor. The HTC One won almost every award in the 2013 knocking out the competition. Let's hope the HTC One+ will repeat this great success!

To summarize:

1. Name: HTC One+ (HTC M8)
2. Screen: 5" FullHD 1080p covered by Gorilla Glass 3
3. Battery: 2900mAh
4. Camera: 6MP or 8MP with UltraPixel™ technology and double lens
5. SoC: Qualcomm® Snapdragon™ 805
6. RAM: 2GB LPDDR3
7. Buttons: no capacitive buttons
8. OS: Android KitKat with HTC Sense™ 6.0
9. SIM: micro-SIM
10. Front camera: 2.1MP
11. NFC: yes

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Merry Christmas everyone!

Android Revolution HD Team would like to wish you all Merry Christmas and a happy New Year 2014.

May love and happiness be a part of your everyday life. 

Forget about the problems and enjoy the moment. Smile, laugh and share the love.

Of course, we also wish you quick Android updates and a lot of flashing.

Android Revolution HD

How to: use "adb sideload" on your Android device

Probably every Android power-user at least once in his life used ADB - Android Debug Bridge. It is a versatile command line tool that lets you communicate with an emulator instance or connected Android-powered device. Using ADB shell commands gives you additional control over your device and sometimes it can save your device from being bricked (example: How to: copy ROM zip file to the freshly wiped device). You can find some more basic information about ADB here.

Since Android Jelly Bean there has been a new ADB mode available in the AOSP recovery, incorporated by the Android developer community into custom recoveries too. It is called "ADB sideload" and most of you probably have heard about it already. This is an alternate method to the one I wrote about here - How to: copy ROM zip file to the freshly wiped device. The main difference is that ADB sideload works only with recoveries based on Jelly Bean source or newer. I believe that ADB sideload was created to simplify the process of flashing/restoring Android update.zip packages.

Keep in mind that while using ADB sideload, the regular ADB shell won't work. To be able to use SIDELOAD mode make sure you're running latest ADB drivers from the Android SDK (Platform-tools). Here are the simple steps you need to follow to flash update.zip package using adb sideload mode (based on stock Android recovery):

1. Place the ZIP package you want to install in the same location where you keep ADB drivers - adb.exe, AdbWinApi.dll and AdbWinUsbApi.dll (usually it's SDK\platform-tools)
2. Make sure you have USB debugging enabled in Settings > Development on your device
3. Make sure your phone drivers are installed on the PC you're going to use
4. Boot your device in recovery mode (Android logo with a exclamation mark) and connect your device to PC
5. Hold down "power" button first, followed quickly by "volume up" button. You should now see the recovery menu
6. Use the volume up/down keys to select "apply update from ADB," then press power to select it
7. Open a command prompt on the PC (cmd.exe), type and confirm with ENTER:
8. cd /d (for example: cd /d c:\SDK\platform-tools) or you can open your SDK/platform-tools folder, then press SHIFT button and the right-click mouse button and choose “Open command prompt here”
9. adb sideload .zip (for example: adb sideload update.zip)
10. The zip package will begin installing. When it's done, select "reboot system now."

How is that different from the alternative method? You don't have to manually create the proper folders structure, push the file and later install if from inside the recovery menu. The result is basically the same, because ADB sideload is also transferring the zip file into the device internal memory and later it automatically begins the installation procedure. However, it works only with recoveries based on Android Jelly Bean source.

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How to: manually install an OTA update on your HTC device

Sometimes it turns out that your device for some reason can't find the most recent OTA (Over The Air) update. However, there is a solution to apply OTA update manually, without being forced to wait for the update being downloaded and installed by your device.

Facts you need to know before continuing:

1. This method has nothing to do with the "adb sideload" feature available on Android devices since Jelly Bean. It should work on every Android HTC device.
2. Read about different software versions for the HTC devices here. Keep in mind that the OTA update must match the software version on your device. Each original OTA update.zip package has 2 different software versions in its name - the version of the software that must be currently installed on your device and the version of the software that your device will run after the update. For example:

OTA_M7_UL_JB43_SENSE55_MR_HTC_Europe_3.62.401.1-2.24.401.8_release_338160gxmo5sd9337kadux.zip

As you can see, 2.24.401.8 is the software version you must currently have installed to be able to run the OTA and 3.62.401.1 is the version of the software expected after the update. You can't flash an OTA update on a different software version to that expected by the OTA update for two main reasons:

1. Formal reason - the OTA update.zip package checks if your system is running the expected software version before it starts to install the update:

   assert(file_getprop("/system/build.prop", "ro.build.fingerprint") == "htc/htc_europe/m7:4.2.2/JDQ39/235216.8:user/release-keys");

   This must match the following build fingerprint from the build.prop. If the versions don't match, the installation of the OTA package will be cancelled.
   

   ro.build.fingerprint=htc/htc_europe/m7:4.2.2/JDQ39/235216.8:user/release-keys

2. Technical reason - OTA update.zip packages usually contain patches for the target files. This way OTA update doesn't have to be 1GB size, even if it is supposed to update the whole OS to the newer version. Patch files have an *.apk.p extension (f.g. Camera.apk.p) and each patch file must match the target file (f.g. Camera.apk). To make it possible, OTA update.zip package checks the MD5 checksum of each file on the system partition on your device:

   assert(apply_patch_check("/system/app/Camera.apk",

   "b3b79e40bad0b1bec5fb949ac5f8662f91bee714",

   "5a5bf63e3d7c9de52a7d8d7a292e158263783844"));

   And finally, if the MD5 is correct it applies the patch. All these commands are stored in META-INF\com\google\android\updater-script of each OTA update.zip package. If the MD5 is incorrect, or at least one file is missing, the installation of the OTA package will be cancelled.
   

   assert(apply_patch("/system/app/Camera.apk", "-",
   b3b79e40bad0b1bec5fb949ac5f8662f91bee714, 4229394, 
   5a5bf63e3d7c9de52a7d8d7a292e158263783844,
   package_extract_file("patch/system/app/Camera.apk.p")));

Now you are ready to manually apply the OTA update on your device. The method you'll use is based on Android stock recovery.

1. Make sure you have the stock (original) recovery flashed on your device
2. Make sure you're running a completely unmodified operating system. Additional files like Superuser.apk or su binary are allowed, you just can't have any system files changed or removed (due to the MD5 check)
3. Make sure you have a reasonable amount of battery charge remaining
4. Make sure the OTA update you're about to install matches the software version on your device
5. Copy the OTA update.zip package to your device (internal storage preferred)
6. Turn OFF the device (make sure fastboot mode is disabled in settings)
7. Hold your volume down and power keys until the bootloader starts up
8. Using the volume keys, navigate down to RECOVERY and press power
9. You are now in stock recovery mode. You should see nothing more than a (sometimes spinning) Android with the red exclamation mark above it (an empty black screen is also possible). Wait for a few seconds
10. First hold volume up, then (with volume up held down) press power button to enter the main recovery menu. This keys combination may vary from device to device. Try different keys combination if the above one doesn't work (might be all three keys all together too)
11. Navigate down to "apply from phone storage" text and press power to confirm
12. Navigate to the location where you copied the OTA update.zip package and press power to confirm
13. Wait (sometimes you might need to follow further instructions on the screen) until the update process is finished
14. Once system is booted you should see a confirmation about the successfully flashed update.

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HTC ROM Update Utility (RUU) variants explanation

Owners of HTC devices might be a little confused when it comes to understanding the current method of numbering used by HTC to mark their software updates. Here you can find a short explanation of this matter.

First of all, we all know that HTC sells their devices all over the world. Every carrier and region of the world has some more or less different "local settings". By "local settings" I mean things like: emergency call numbers, languages, time-zone settings, network settings, carriers branding, GPS settings and more. Because of that each software for even the same device must be different.

Secondly, even the same device might use different hardware related to the region of the world. For example, HTC One is available in at least 6 different hardware configurations. One of the main difference is modem version. GSM version of the HTC One uses MDM8215 chip and LTE variant has MDM9215. Verizon (US) is known to have MDM9615. So that's already 3 different versions of the same device.

Every HTC update has the following numbering structure:

a.bb.ccc.d

a - the first number of the software. Normally it doesn't increase very often, but when it does, it usually means newer Android version.

bb - this number is also a software number. Increasing bb number means some more or less major update based on the same Android version, but sometimes it might even bring newer version of the HTC Sense.

ccc (also cc or cccc) - this is the number of the region/carrier. It has nothing to do with the software itself being newer or older. More details below.

d (sometimes dd) - the third part of the software version (the fourth one in the RUU name). Usually indicates some minor update with some hot fixes.

Example: 3.20.401.3

So basically, when you are interested in the software version, you should look at a.bb.d (3.20.ccc.3) because ccc (401) means only the region/carrier variant of the software.

Here is the list I was able to gather of possible RUU variants:

a.bb.61.d - Orange UK (United Kingdom)

a.bb.65.d - Orange CH (Switzerland)

a.bb.69.d - Orange PL (Poland)

a.bb.73.d - Orange FR (France)

a.bb.75.d - Orange ES (Spain)

a.bb.110.d - T-Mobile UK (United Kingdom)

a.bb.111.d - T-Mobile DE (Germany)

a.bb.112.d - T-Mobile AT (Austria)

a.bb.113.d - T-Mobile CZ (Czech Republic)

a.bb.118.d - T-Mobile PL (Poland)

a.bb.161.d - Vodafone UK (United Kingdom)

a.bb.163.d - Vodafone FR (France)

a.bb.165.d - Vodafone IT (Italy)

a.bb.166.d - Vodafone CH-DE (Switzerland - Germany)

a.bb.168.d - Vodafone GR (Greece)

a.bb.169.d - Vodafone AT (Austria)

a.bb.206.d - O2 UK (United Kingdom)

a.bb.207.d - O2 DE (Germany)

a.bb.401.d - World Wide English (WWE)

a.bb.415.d - Arabic (UAE/Middle East)

a.bb.468.d - Turkey

a.bb.497.d - Morocco

a.bb.498.d - WWE Brightpoint US (United States)

a.bb.502.d - Cingular US (United States)

a.bb.531.d - T-Mobile US (United States)

a.bb.631.d - Rogers Canada (WWE)

a.bb.651.d - Sprint US (United States)

a.bb.661.d - Telus WWE (Canada)

a.bb.666.d - Bell Canada

a.bb.707.d - Asia (WWE)

a.bb.708.d - Asia HK (Hong Kong)

a.bb.709.d - Asia TW (Taiwan)

a.bb.720.d - Asia (India)

a.bb.728.d - Virgin AU (Australia)

a.bb.751.d - Chunghwa Telecom (Taiwan)

a.bb.771.d - Hutchison 3G UK (United Kingdom)

a.bb.777.d - ?

a.bb.841.d - Telsra WWE (World Wide English)

a.bb.862.d - Voda-Hutch AU (Australia)

a.bb.901.d - TIM IT (Italy)

a.bb.911.d - SK Telecom (South Korea)

a.bb.980.d - Optus AU (Australia)

a.bb.999.d - HTC Test RUU

a.bb.1400.d - China

a.bb.1401.d - ?

a.bb.1403.d - HTC China CMCC (China Mobile Communications Corporation)

a.bb.1540.d - HTC One U.S. Developer Edition

a.bb.1600.d - ?

a.bb.1700.d - HTC One Google Edition

The list is quite long, and I'm sure there are still some some missing. If you know more variants, please let me know in the comments section.

The 401 and the 707 devices are usually the first ones that HTC prepare updates for. Carrier branded software is usually months after the WWE updates.

Finally, keep in mind that each software version is connected with the CID (Carrier ID) and MID (Model ID) of your device. That means you can't use whichever version you want, unless you have S-OFF on your device. Each ROM Update Utility.exe package will check your device details (bootloader version, MID and CID) before starting the update process.

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