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DELL Latitude E6320 laptop battery

Posté le 14/10/2017 à 06:35 - poster un commentaire

Dubai International Airport in the United Arab Emirates is the busiest airport in the world and handled 78 million passengers in 2015. It is the main hub for Emirates which flies direct to the US. It has been suggested that the fact that Emirates, Etihad Airways and Qatar Airways were included in this ban by the US but not the UK could be more to do with actions by their US competitors than anything related to safety.US airlines have long complained that the Gulf State airlines receive subsidies from their governments and so represent unfair competition. President Trump has been threatening to deal with these airlines and protect the US’s national carriers.For travellers needing to go to the US who would normally travel through one of the effected airports, all electronic devices other than mobile phones will have to be packed in checked-in luggage.All of the advice from insurers, travel sites and the TSA themselves has always been not to pack an expensive laptop in checked in luggage. If you do, then make sure that there is a backup left at home or work, that the computer is locked and preferably the disks encrypted.Make sure the device is switched off and not simply asleep. Putting the device in a protective sleeve may help with impacts and using a solid shell suitcase an advantage.For some travellers, leaving laptops in checked in luggage will represent a security risk and it is highly likely that security agencies, amongst others, will take advantage of the relative ease of access to targeted devices to examine them.

If at all possible, take an alternative inexpensive laptop, Chromebook or tablet instead. Keep sensitive documents on a USB and not on the device.It is entirely possible that other countries may follow the move of the US and UK but it may still be possible to take a different airline using a route that doesn’t go through the Middle East.Another option is not to travel to the US at all. 6,600 academics have signed a pledge to boycott all international conferences held in the US in response to Trump’s first Muslim Ban.Right before Christmas, Consumer Reports, one of the most famous product review publications, announced that it could not recommend Apple's latest MacBook Pro because of inconsistent battery life.But shortly after the review was published, questions about Consumer Reports' testing surfaced, such as how it claimed to get both 3.75 hours of battery life and 19.5 hours from the same laptop — which is obviously a huge disparity. Turns out, it was a software issue, Consumer Reports said in a blog post on Tuesday. Consumer Reports now says the MacBook Pro is poised to receive a recommended rating again if battery life remains consistently high. We communicated our original test results to Apple prior to publication on Dec. 22 and afterward sent multiple rounds of diagnostic data, at the company’s request, to help its engineers understand the battery issues we saw in our testing, Consumer Reports wrote in a blog post.

After investigating the issue, Apple says that the variable battery performance we experienced is a result of a software bug in its Safari web browser that was triggered by our test conditions.Apple said that the issue was related to a setting that Consumer Reports uses on its testing. We learned that when testing battery life on Mac notebooks, Consumer Reports uses a hidden Safari setting for developing web sites which turns off the browser cache. This is not a setting used by customers and does not reflect real-world usage, an Apple spokesperson told Business Insider. “We appreciate the opportunity to work with Consumer Reports over the holidays to understand their battery test results. We learned that when testing battery life on Mac notebooks, Consumer Reports uses a hidden Safari setting for developing web sites which turns off the browser cache. This is not a setting used by customers and does not reflect real-world usage. Their use of this developer setting also triggered an obscure and intermittent bug reloading icons which created inconsistent results in their lab. After we asked Consumer Reports to run the same test using normal user settings, they told us their MacBook Pro systems consistently delivered the expected battery life. We have also fixed the bug uncovered in this test. This is the best pro notebook we’ve ever made, we respect Consumer Reports and we’re glad they decided to revisit their findings on the MacBook Pro.”

Battery life is an explosive issue. Literally, as Samsung is discovering to its dismay. The company’s Galaxy Note 7 smartphone was praised upon release for best-in-class battery life, far outpacing its key competitor, the iPhones 6S and 7 Plus. Then it started blowing up. Samsung issued a recall and replace programme, and the replacements also started blowing up, forcing the company to suspend production entirely.The affair marks the latest road block on the long fight to improve the batteries that power our electronics. While processing speed doubles around every 18 months, battery capacity takes almost a decade to improve to the same degree. That gap is starting to cause problems, but as Samsung has found to its cost, it’s not easy to fix.A smartphone often lasts less than a day, a laptop sometimes only a few hours and an electric car struggles to go 350 miles. So why is it that battery life is still such a problem – and when are we going to fix it?Batteries are small containers of chemical energy. When a smartphone is plugged into the mains, electricity is used to reset a chemical reaction within the battery, transferring electrons from the negative anode to the cathode – the positive end of the battery.

Once charged, the battery can then create electricity by driving electrons through a circuit, in this case a smartphone, to the anode and will continue to do so until all of the electrons contained within the battery have transferred to the anode or a built-in switch disconnects the battery.Inside a typical battery you have an anode, a cathode and electrolyte – something for the positive ions to travel through.Lithium-ion batteries found in most smartphones and electronics have a metal oxide cathode made of a cobalt, nickel, manganese or iron mix, a porous graphite anode that holds lithium ions within it and a lithium salt electrolyte.Positively charged lithium ions travel through the electrolyte from the anode to the cathode driving electrons through the smartphone as required and back to the anode.The principle of the battery may be simple, but the chemistry and technology to make it work is not. The major limiting factor for batteries is their energy density.A battery can only generate as much electricity as its chemical components can store energy. Everything that is not the active material within the battery is effectively dead weight, including the casing, the controller chips, the wires to carry the current out – they all add weight but not power.

A typical lithium ion battery within a smartphone has an energy density around 150 Watt-hours per kilogram (Wh/kg). While Lithium ion battery energy density has improved since its introduction in the early 1990s, it is held back by its construction and chemistry.The only way to immediately increase a smartphone’s battery life with current technology is to increase the power efficiency of the smartphone’s electronics and increase the size of the battery – but thinner and thinner smartphones demand thinner and thinner batteries.Battery life doesn’t stay constant for the entire life of a smartphone – it diminishes slowly over time, as the battery is discharged and recharged.This is because the chemical reaction that produces the electricity causes thin layers of lithium to be laid down on the electrodes, which reduces the amount available to generate electricity and increases the internal resistance of the battery.The higher the resistance the harder the battery has to work to maintain a usable voltage and so the amount of power it can produce per charge decreases. You might remember this bit from school:Batteries with much higher energy density than lithium-based cells are already available, but they aren’t safe enough for use in portable electronics.

“The more energy you put into a box, the more dangerous it’s going to be,” says Dr Billy Wu, lecturer at Imperial College London’s Dyson School of Design Engineering. “Safety is absolutely key and thermal management is crucial. If a battery heats up beyond 80C you hit what is called thermal runaway, where the components start to decompose, and that’s when it can explode.”The specific cause of Samsung’s issues with exploding batteries is unknown, the company just cites “a battery cell issue”.In the immediate term, battery advances will come by bringing existing lithium-ion technologies closer to their theoretical limits, which will increase the power density of batteries.A typical lithium-ion battery using lithium manganese oxide has a theoretical power density of 280 Wh/kg, but the final product only has 150Wh/kg so there is certainly room for improvement.“It’s about optimising the structure within the battery,” says Wu. “If you imagine inside your battery you have this porous structure full of the active material.”“For higher power output, you need a more porous structure to increase the surface area and allow more lithium ions through at any one time, but because it’s got more holes it holds less active material, which in turn gives you lower capacity.”

New, advanced battery chemistries such as lithium-sulphur and lithium-silicon are also being worked on, with companies around the UK currently developing the technology.Solid state batteries are one possible future, where the liquid electrolyte in the battery is replaced by a solid substance, which will provide significant safety improvements.“The main advantage of solid state batteries is that you can go back to using lithium as the anode material, which has really good power and energy density, but wasn’t safe with liquid electrolytes,” explains Wu.Solid-state batteries will remove the need for the porous carbon anode and therefore removes more of the weight from the battery that doesn’t contribute to generating power.Metal air batteries, using zinc, lithium or aluminium are also on the horizon, but are 20 years away from being available in a commercial application according to Wu.There are a few things you can do to help prolong the life of your battery. The nature of the chemical reaction inside the battery means that it has to work harder in the last 20% of discharge and above 80% of charging.Keeping a lithium ion battery roughly between 80% and 20% of charge will help it keep a greater amount of its capacity for longer. Smart power management systems are currently being developed that do just that when plugged into a wall overnight.

Batteries should never be left constantly plugged in, which is particularly applicable to laptops. They are kept in better working order if they are discharged and recharged every so often. Once a month should do it.On Tuesday morning, Microsoft announced Windows 10 S — a brand-new version of its flagship operating system, aimed squarely at undermining the meteoric rise of Google's low-cost Chromebooks in the American classroom.So what does the S stand for? Streamlined, significant performance, security, explains Microsoft Windows boss Terry Myerson. But I personally like to think of it as the 'Soul' of today's Windows.Windows 10 S is designed to run well even on lower-end laptops, promising a boost to battery life and speed over your everyday Windows computer.But those perks come with a caveat: You can only download and use apps from the Windows Store app market. That means, at least, you'll be using Microsoft's own Edge web browser, in lieu of any other browsers in the store.That's key for classrooms, Myerson says, where teachers want control over what apps their students can use, and students want something with great battery life and a selection of familiar Windows software. Minecraft, for instance, won't run on a Chromebook, nor will the full desktop versions of Microsoft Office.

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