Wednesday, September 30, 2015

Making the Most of Your Device’s Battery

There seems to be a lot of misinformation out there about the best way to care for the battery in your cell phone, laptop, tablet, or other electronic device.  It seems that most people have not been given proper instructions on how to best care for their batteries, and they end up wearing them out prematurely.  By taking care of your battery, you can make your device perform optimally for years.

Technology has changed quite a bit over the years, that’s for certain.  And so have the batteries that power our devices, and the chargers that keep them running.  Unfortunately much of society hasn’t been taught how to care for them to get the most out of them.  So let’s set the record straight.

Myth: I should let the battery on my device drain all the way down before charging it again.

Fact: This was true in the days we used NiCd rechargeable batteries in our devices.  Very few devices still use NiCds; they are heavy and hold relatively little energy.  Today, we use Lithium Ion batteries, and draining a Li-ion battery shortens its life dramatically.  In fact, in some cases when a Li-ion battery is drained all of the way it won’t accept a charge at all.  Bad things happen to Li-ion batteries when they are allowed to get too low.

For example, if a Li-ion battery is allowed to fully discharge, it will only accept a few hundred charges before it dies.  If a battery is only allowed to dip to 90% charge each time it is used, it will be good for many thousands of charge cycles.  A properly cared-for battery can last for many, many years.  A battery improperly cared for can become useless in under a year.

Myth: It is bad to leave my device plugged in all of the time.

Fact: For devices with really primitive charging circuitry, this is actually true.  These devices would overcharge a battery, and damage it. 

But those days are behind us.  Any modern cell phone, laptop, or tablet has intelligent charging circuitry that shuts off the charger when the battery is full, eliminating the need to unplug when the battery is charged.  You don’t need to unplug manually.

You may even see evidence of the intelligent charger.  If your device’s battery charge actually drops while plugged in, this is the intelligent circuitry doing its job, turning on and off to prevent unnecessary wear and tear.  Most devices hide this on/off cycle from you, though, so even devices that stay at 100% when plugged in are still managing your battery properly.

Myth: It doesn’t matter when I plug my device in, the battery is going to wear out in a couple years anyway.

Fact: Batteries actually do have a limited number of charge cycles that they can handle.  And each charge cycle holds just a little bit less energy than the previous.  But the loss in total capacity can be minimized by making sure that batteries aren’t drained any more than they need to be.  The way you handle charging your device can extend or shorten its life significantly.  Deep discharges wear out a battery faster than letting the battery drop just a few percent before plugging it back in.  To maximize the life of your battery, just plug in whenever you can.

Myth: It isn’t good for a battery to only let it discharge a little bit before plugging it back in.

Fact: The Lithium Ion batteries that power our devices actually last longer when they aren’t allowed to discharge much.  They last longer when their charge isn’t allowed to drop.  They “like” to be constantly topped off.  The old NiCd batteries we used years ago worked best when discharged fully before charging, but the Lithium Ion batteries we use today wear out faster when allowed to discharge.  So plug in to keep your devices topped off whenever you can.

Myth: Lithium Ion batteries are dangerous, and can explode, especially if overcharged.

Fact: Lithium Ion batteries are potentially dangerous.  If allowed to overheat they can catch fire –violently – and even explode.  Fortunately, reputable manufacturers place multiple failsafes into modern batteries to prevent this from happening.  The number of cases of batteries overheating or exploding has dropped dramatically in recent years.

But because batteries have to be designed and built properly to prevent overheating, fires, and explosions, you should avoid purchasing no-name aftermarket batteries.  You just can’t be sure if they’re built with the same level of protection as batteries from the original device manufacturer.  It just doesn’t pay to buy batteries from brands you don’t know you can trust.

Myth: All Lithium Ion batteries are the same, so it doesn’t matter if I buy a cheap no-name replacement.

Fact: Batteries are most definitely not all created equal.  Aftermarket batteries often hold less of a charge than the originals (even when labeled as if they held more), and very often aren’t built with the same level of protections against fire and explosion.  They also tend to wear out faster.  It generally isn’t worth it to buy batteries from anyone other than the original device manufacturer, or at least a trusted brand. 

Myth: The battery in my device can’t be replaced.  The cover can’t be removed.

Fact: We have certainly seen a trend in recent years for device manufacturers to take away the ability for owners to swap out a battery by removing access covers.  But in most cases, batteries can still be replaced by a qualified service center.  Don’t be tempted to throw away an old phone just because it doesn’t hold a charge very well.  Replace the battery and keep using the device, or donate it to someone else who can enjoy it.  (Reusing is better than recycling, and far better than discarding.)

Myth: It’s okay to use an aftermarket charger.

Fact: It depends on what type of charger you’re talking about.  If you’re talking about a charger that you plug into a phone or tablet, it may not matter what charger you use in terms of the life of your battery.  But if you’re talking about a charger that you insert a loose battery directly into, it can make all of the difference in the world.  Cheap battery chargers don’t often have the intelligence that they need to maintain a battery properly.  Stick to chargers from the original manufacturers, or at least a well-known and well-respected brand.

Myth: If I don't have time to fully charge the battery, I shouldn't plug my device in to charge because short charging cycles harm my battery.

Fact: False. Even short charging cycles are helpful.  Plug in whenever you can.

Myth: Using a charger with a higher milliamp rating than the original will damage a device/battery.

Fact: The milliamp rating on a charger is simply the maximum amount of current that it can potentially put out.  It doesn’t mean that it will force more current into a device than it can handle.  If a device is designed to draw 500mA, and you plug it into a 1000mA charger, the device will still draw just 500mA.  It is generally just fine to use a charger with a higher milliamp rating, so long as the voltage is correct.

Myth: I should never allow my battery to drain fully.

Fact: Okay, well, yes, you should never drain the battery all the way until your device shuts itself off.  That is bad.  But it is a good idea to drain your battery down to 10% or so a couple times per year.  Not because doing so is actually good for the battery, but because it is actually good for the device it is powering.  It is quite difficult for devices to figure out the charge level of Lithium Ion devices (it involves a lot of guesswork), and putting a device through a discharge / recharge cycle gives the device a chance to re-learn how your battery is operating.  You’ll be rewarded with a more accurate gauge of the amount of battery life you have left.

Myth: It isn’t worth it to do anything to improve the battery life of my device.

Fact: Because draining a Li-ion battery is bad for it, you can extend the life of your device’s battery by taking a few steps to reduce the amount of battery charge being used.  Things like changing the amount of time a device sits idle before automatically going to sleep, reducing the brightness of your screen, using Wi-Fi instead of a cellular connection, or closing apps you aren’t using can make a huge difference, and can extend the life of your battery dramatically.

Myth: It is okay to throw away a used battery in the trash.

Fact: Nope. Lithium Ion batteries should always be recycled.  It is easy to do; most electronics and office supply stores will recycle old batteries for you at no charge (pun intended).

Myth: Batteries perform differently based on temperature.

Fact: This one is actually true.  A warm battery doesn't output as much energy as one at room temperature.  Likewise, a cold battery doesn't output as much as one at room temperature.  Batteries operate most ideally at the same temperatures that we as humans do.

Similarly, batteries charge best at room temperature as well.  A cold battery won't charge as fast as one at room temperature.  And trying to charge a hot battery isn't a good idea.  So if your device is too warm or too cold, give it some time to return to room temperature before plugging it in.

Batteries which become too warm are also damaged by the heat.  A battery that overheats because the device is in the sun, or is hot because the electronics inside have gotten warm, can easily be permanently damaged.

Myth: It's okay to use a battery which has swelled up.

Fact: A battery which has been overcharged or overheated can sometimes swell up and become larger than it is intended to be.  These are potentially dangerous to use.  The act of swelling up can damage some of the protection circuitry inside.  Once a battery has swelled it should be properly recycled and replaced.  There is no way to repair a swelled-up battery.

Myth: You have oversimplified how to care for a battery here.

Fact: Okay, yes, I have oversimplified a bit.  I'm aware that my advice isn't 100% accurate.  I'm aware that modern electronics do push batteries harder than they maybe should.  But I feel my advice is still good because actual battery best practices are too complicated and nobody would ever actually attempt to follow those rules exactly.  We aren't NASA using devices that have to survive in space for a decade.  Nobody would be happy with the battery life of their devices if they followed actual best practices, nobody would take the time to monitor their devices that closely to maintain them perfectly, and any potential damage done by following my advice compared to ideal is for all practical purposes insignificant.  Device owners can benefit significantly from the advice here compared to how they are likely handling their devices now.  So I've opted to simplify the rules to make them easier to follow. So please forgive me for not over-complicating the matter.

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