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How you charge your mobile phone could compromise its battery lifespan

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Researchers at WMG at the University of Warwick have found that use of inductive charging, whilst highly convenient, risks depleting the life of mobile phones using typical LIBs (Lithium-ion batteries)

Consumers and manufacturers have ramped up their interest in this convenient charging technology, abandoning fiddling with plugs and cables in a favour of just setting the phone directly on a charging base.

Standardisation of charging stations, and inclusion of inductive charging coils in many new smartphones has led to rapidly increasing adoption of the technology. In 2017, 15 automobile models announced the inclusion of consoles within vehicles for inductively charging consumer electronic devices, such as smartphones — and at a much larger scale, many are considering it for charging electric vehicle batteries.

Inductive charging enables a power source to transmit energy across an air gap, without the use of connecting wire but one of the main issues with this mode of charging is the amount of unwanted and potentially damaging heat that can be generated. There are several sources of heat generation associated with any inductive charging system — in both the charger and the device being charged. This additional heating is made worse by the fact that the device and the charging base are in close physical contact, any heat generated in one device may be transferred to the other by simple thermal conduction and convection.

In a smartphone, the power receiving coil is close to the back cover of the phone (which is usually electrically nonconductive) and packaging constraints necessitate placement of the phone’s battery and power electronics in close proximity, with limited opportunities to dissipate heat generated in the phone, or shield the phone from heat generated by the charger. It has been well-documented that batteries age more quickly when stored at elevated temperatures and that exposure to higher temperatures can thus significantly influence the state-of-health (SoH) of batteries over their useful lifetime.

The rule of thumb (or more technically the Arrhenuis equation) is that for most chemical reactions, the reaction rate doubles with each 10 °C rise in temperature. In a battery, the reactions which can occur include the accelerated growth rate of passivating films (a thin inert coating making the surface underneath unreactive) on the cell’s electrodes. This occurs by way of cell redox reactions, which irreversibly increase the internal resistance of the cell, ultimately resulting in performance degradation and failure. A lithium ion battery dwelling above 30 °C is typically considered to be at elevated temperature exposing the battery to risk of a shortened useful life.

Guidelines issued by battery manufacturers also specify that the upper operational temperature range of their products should not surpass the 50?60 °C range to avoid gas generation and catastrophic failure.

These facts led WMG researchers to carry out experiments comparing the temperature rises in normal battery charging by wire with inductive charging. However the WMG were even more interested in inductive charging when the consumer misaligns the phone on the charging base. To compensate for poor alignment of the phone and the charger, inductive charging systems typically increase the transmitter power and/or adjust their operating frequency, which incurs further efficiency losses and increases heat generation.

This misalignment can be a very common occurrence as the actual position of the receiving antenna in the phone is not always intuitive or obvious to the consumer using the phone. The WMG research team therefore also tested phone charging with deliberate misalignment of transmitter and receiver coils.

All three charging methods (wire, aligned inductive and misaligned inductive) were tested with simultaneous charging and thermal imaging over time to generate temperature maps to help quantify the heating effects. The results of those experiments have been published in the journal ACS Energy Letters in an article entitled “Temperature Considerations for Charging Li-Ion Batteries: Inductive versus Mains Charging Modes for Portable Electronic Devices.”

The graphics with this press release illustrates three modes of charging, based on (a) AC mains charging (cable charging) and inductive charging when coils are (b) aligned and (c) misaligned. Panels i and ii show a realistic view of the charging modes with a snapshot of the thermal maps of the phone after 50 min of charging. Regardless of the mode of charging, the right edge of the phone showed a higher rate of increase in temperature than other areas of the phone and remained higher throughout the charging process. A CT scan of the phone showed that this hotspot is where the motherboard is located

  • In the case of the phone charged with conventional mains power, the maximum average temperature reached within 3 hours of charging did not exceed 27 °C.
  • In contrast this for the phone charged by aligned inductive charging, the temperature peaked at 30.5 °C but gradually reduced for the latter half of the charging period. This is similar to the maximum average temperature observed during misaligned inductive charging.
  • In the case of misaligned inductive charging, the peak temperature was of similar magnitude (30.5 °C) but this temperature was reached sooner and persisted for much longer at this level (125 minutes versus 55 minutes for properly aligned charging).

Also noteworthy was the fact that the maximum input power to the charging base was greater in the test where the phone was misaligned (11W) than the well-aligned phone (9.5 W). This is due to the charging system increasing the transmitter power under misalignment in order to maintain target input power to the device. The maximum average temperature of the charging base while charging under misalignment reached 35.3 °C, two degrees higher than the temperature detected when the phone was aligned, which achieved 33 °C. This is symptomatic of deterioration in system efficiency, with additional heat generation attributable to power electronics losses and eddy currents.

The researchers do note that future approaches to inductive charging design can diminish these transfer losses, and thus reduce heating, by using ultrathin coils, higher frequencies, and optimized drive electronics to provide chargers and receivers that are compact and more efficient and can be integrated into mobile devices or batteries with minimal change.

In conclusion, the research team found that inductive charging, whilst convenient, will likely lead to a reduction in the life of the mobile phone battery. For many users, this degradation may be an acceptable price for the convenience of charging, but for those wishing to eke out the longest life from their phone, cable charging is still recommended.

Source: https://www.sciencedaily.com/releases/2019/06/190626124943.htm

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Research

Android 10: 8 of the best features and how to use them

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Android 10 is rolling out to Google’s Pixel phones right now, with more devices to gain the latest version of Android in the near future. Google recently announced Android 10 as the official name, replacing Android Q and the dessert naming scheme Google has always used. Operating system updates like Android 10 add new features and capabilities and can be refreshing if you’re growing tired of your phone. Google released the first beta of Android Q in March, and we’ve been testing it all along. 

From a new Bubbles notification feature, full-on gesture navigation, improved privacy settings and a slick Live Caption feature — there’s a lot to like about Android 10. Let’s take a look at some of the highlights. 

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Android 10’s Bubbles feature should feel familiar to users of Facebook Chat Heads. Screenshots by Jason Cipriani/CNET

Bubbles

Do you still use Facebook Messenger’s Chat Heads feature? If so, then you’re going to love Android 10’s new Bubbles feature. Bubbles work just like Chat Heads, with a circular notification floating above whatever is on your screen. Google wants developers to be mindful of what types of apps use Bubbles simply because a stream of notifications showing up on your screen, regardless of what you’re doing, would get real annoying real fast.

As you can see in the screenshots above, Bubbles is working with the Google Phone app. I triggered Bubbles by leaving an active call, after which a small circle showed up with the contact’s picture. While dragging the Bubble around, two options showed up at the bottom of the screen: Hide and End Call. Dragging the icon to either option caused that action. A single tap on the Bubble revealed a few more options, such as enabling the speaker or muting the call. 

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Android 10 makes it a breeze to share Wi-Fi networks with a QR code. Screenshot by Jason Cipriani/CNET

Wi-Fi and QR codes

Sharing your Wi-Fi network password with friends or asking for theirs can be awkward. Android 10 has a new feature that lets you create a QR code for your Wi-Fi network or scan a QR code to join a Wi-Fi network, directly in the device’s Wi-Fi settings. To use this new feature, go to Wi-Fi settings and then select your home network, followed by the Share button with a small QR code just above it. 

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Screenshot by Jason Cipriani/CNET

Undo app removal

Ever accidentally remove an app from your home screen, and then realize you can’t remember which app was there? I have.

With Android 10, you have a few seconds after an app has been removed to undo the change. You’ll find the undo button along the bottom of the screen. Press it and bam, the app is back where it belongs.

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You have new options when it comes to approving location access in Android 10.Screenshot by Jason Cipriani/CNET

Location control

Android is finally getting more granular control over how an app can use location information. Currently, you can give an app access to your location either all the time or not all. With Android 10, you will gain the option of letting an app access your location information only while you’re actively using the app. Not only is this a privacy matter, but it’s sure to help save on battery life.

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The new privacy settings in Android 10 are long overdue. Screenshots by Jason Cipriani/CNET

Privacy settings

With Android 10, there’s now a dedicated Privacy section in the settings app. Opening it will reveal the various permissions apps can request for things like calendar, location, camera, contacts and microphone.

Android has lacked a clear-cut way to view what apps have access to what data on your device. The new section makes it easy to discover and revoke permissions for specific apps. Take a few minutes to learn exactly what can be done in the new Android 10 Privacy settings page. Trust us, it’s worth it. 

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Android 10’s new notification settings will help you limit the dings and beeps coming from your phone. Screenshots by Jason Cipriani/CNET

Better notification controls

When you long-press an alert, you’re now given two different options: Alerting and Silent. Selecting Alerting will allow the app to make sound with each new alert. Silent will not make a sound or cause your phone to vibrate. You can further tailor how notifications behave by going into Settings > Apps & notifications > Notifications.

This is a small but important feature because you no longer have to dig into the Settings app to figure out how to customize an app’s alerts. You simply long-press, pick an option and you’re done

Live Caption

As a way to make Android more accessible, Google developed Live Caption. The feature will live-caption any video that’s being played, without a data connection. To activate Live Caption, play a video and then press a volume button. The volume slider that shows up will have a caption button at the bottom — tap it. You can then move around the caption by dragging it around the screen. 

You can install Android 10 if you have a Pixel phone, then be sure to familiarize yourself with gesture navigations and dig into the new privacy settings. 

Source: https://www.cnet.com/how-to/android-10-8-of-the-best-features-and-how-to-use-them/

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iPhone 11? Phone XI? Exactly What Will Apple Name Its 2019 Phones?

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Tomorrow, Tuesday, September 10, Apple will introduce its latest iPhones, plus a new Apple Watch and perhaps more stuff.

Apple invite
The invite to tomorrow’s Apple keynote.APPLE

But while we think we know what we’re getting, we still don’t know for sure what the new iPhones are going to be called.

Regular Forbes readers will know that this guessing game is something I do each year. And my track record in 2018 and 2017 is quite remarkable. Well, what I mean is, as you’ll have seen if you clicked on those links, I’m usually wrong.

In 2017 I did think iPhone X was a good name but plumped for another name in the end. Last year, I was completely wrong.

So, at least I’m consistent, right?

Let’s see if I can score a hat trick with a look at the contenders…Today In: Innovation

iPhone 11

Could this be the name? I’m hoping so, mostly because I honestly can’t wait for Tim Cook to say, at last, “these iPhones go to 11”. Though whether a Spinal Tap reference really will make the keynote is another matter.

Well, there’s something straightforward about this, and since we’re all already talking about the iPhone 11, it would make a lot of sense to go with this name. I think it’s pretty likely. But, never forget, Apple doesn’t like to be predictable.

Also, there are three iPhones in the 2018 range, likely to be mimicked this time around. So, which iPhone would be the iPhone 11? When the iPhone X launched, it was the flagship, so does that mean the iPhone 11 will be the replacement for the iPhone XS? I don’t think so.

XR
The current range of iPhone XR colors.APPLE

The entry-level iPhone XR, arguably the most successful phone Apple released last year, is now very much a member of the family. Just as XR indicates an ‘X’-type phone, so this year I think the XR replacement will have 11 in its name.

In fact, as it’s the popular and most affordable iPhone, perhaps it should have the iPhone 11 name all to itself.

What does that mean for the replacements for iPhone XS and iPhone XS Max?

iPhone
iPhone XS Max – a new Max is about to be announced, we think.APPLE

Max makes a return

The one thing I’m sure of is that the word Max will be in the name of the largest iPhone, the presumed 6.5in screener to replace the iPhone XS Max. Before the XS Max, that sized phone was called a Plus size by Apple. To remind you that the display went edge to edge, Apple called it Max. As the next phone will have the same all-screen effect, I am sure Max will be in the mix.

How about Pro?

Pro came up as a possible name choice in 2017 for what turned out to be iPhone X. If the XR replacement is just called iPhone 11, then what do you call the XS replacement? One rumor doing the rounds in iPhone 11 Pro, or just iPhone Pro.

This is not a bad idea, but there’s one sticking point for me: the Lightning connector. While it’s true the first iPad Pro had a Lightning socket, the move to USB-C on the more recent models indicated the importance of the versatile, universally used connector, and now the whole iPad Pro range has USB-C.

I don’t think any iPhone will have a USB-C connector this year.

Of course, Apple can say that one of the reasons the iPad Pro has USB-C is to make it easier to connect the tablet to external devices such as monitors, and that won’t be the purpose with the iPhone, so Lightning is fine, thank you very much.

If it is Pro, then what?

Then there’s the question of whether it should be iPhone Pro or iPhone 11 Pro. Once that’s decided, where do you put the Max? iPhone Pro Max or iPhone 11 Pro both sound like a health supplement, so maybe it could be iPhone 11 Max Pro.

But that’s quite a mouthful.

How about iPhone XI?

Although Apple has favored roman numerals, I don’t think they’ll be used this year. After all, almost everyone talks about the iPhone X, sounding the X as a letter not as ten.

Although Apple is proud of the iPhone X, I think it will move on to regular numbers this time around. Not least so everyone says it right.

What’s the answer then?

I’m betting on iPhone 11 for the XR replacement. Then iPhone 11 with a suffix for the XS successor and the same including the word Max for the largest model. On balance, I think the most likely names for these two are iPhone 11 Pro and iPhone 11 Pro Max or, just possibly, iPhone 11 Max Pro.

But you never can tell with Apple. Only hours until we know.

Source: https://www.forbes.com/sites/davidphelan/2019/09/09/phone-11-phone-xi-exactly-what-will-apple-name-its-2019-phones/?ss=consumertech#2eb9a7ec2c7e

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Employees who are treated rudely get their revenge with the silent treatment, research shows

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Employees who are treated rudely at work get their revenge by withholding important information from colleagues and managers, new research shows.

The British Academy of Management’s annual conference in Birmingham heard today [Thursday 5 September] that employees who experience workplace incivility are more likely to engage in “deviant behaviors” directed toward both colleagues and the organization.

Researchers asked almost 300 employees in US firms to rate how rude colleagues had been to them, and how much they kept silent in order to get even or to harm their employers.

Three academics at the Universite de Pau et des Pays de l’Adour in France conducted online surveys with 297 employees working in various industries in the United States, a representative sample of the workforce.

Professor Jean Pierre Neveu, Dr. Ghulam Murtaza and Rahman Khan asked the employees to rate on a scale of 1 (never) to 5 (every day) how often a colleague or boss had been rude to them during the previous two months. They also asked them to rate from 1 to 5 how much they had remained silent about an important matter when they should have spoken up, in order to get even with a colleague or hurt their employer.

The researchers found that the average score for the rudeness experienced was 2.12, and that for every 1 unit increase, the likelihood that workers would remain silent increased by about a third. An employee who experience rudeness every day would be around twice as likely to remain silent as the average.

Employee silence, an increasingly recognized phenomenon, can be costly for organizations. Examples include staff failing to speak up when workplace plans and procedures are riddled with inaccuracies or faulty thinking.

“Experiencing incivility at work leads to deviant silence in which an individual withholds useful information to harm someone,” Mr Khan told the conference.

Staying silent was “a response to experiencing incivility because the individual thinks that it’s fair to retaliate against the perpetrator,” he said.

“Employees intentionally remain silent about important issues because they perceive their work environment is not conducive for it, which can posit serious harm to the organizations.

“Experiencing workplace incivility may not only be harmful to a victim’s mental health but can also motivate him or her to make unethical choices. In turn, such deviant behaviors can hurt an organization’s culture as well as its financial condition.”

Mr Khan said that staying silent could backfire and created a vicious cycle. “Deviant behavior like hiding valuable information can lead colleagues or superiors to make wrong decisions and may cause negative emotions in them thus further leading to subsequent mistreatment targeted towards the perpetrator as they want to pay him back.”

Source: https://phys.org/news/2019-09-employees-rudely-revenge-silent-treatment.html

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