The 5 Biggest Myths About Smartphone Batteries (and Why They’re Mostly False)

There are a lot of commonly held beliefs out there about how you should and shouldn’t charge the batteries in your smartphone. You know the ones I’m talking about: Don’t keep your phone plugged in all night. You need to “train” your battery to hold a charge.

Well, it turns out that a lot of those tips are pure hooey. To help you sort the facts from the fiction, here’s the truth about five of the most prevalent myths about smartphone batteries. Don’t say we’ve never done anything for you.

1. Keeping your phone plugged in damages its battery

You’ve certainly heard this one before: Keeping your phone plugged in all night when you go to sleep will supposedly overwhelm your handset’s battery, damaging it and keeping it from being able to hold a charge.

The truth of the matter, however, is the exact opposite. Your smartphone is intelligent enough to recognize when its battery is fully charged and, when it does, will stop pulling in power.

In fact, most of today’s phones are so smart that they only pull in a full stream of power until their batteries are charged to about 80 percent. After that, they’ll “trickle” charge until they’re full.

Verdict: BUNK.

2. Charge your phone only when its battery is dead

There’s not a lick of truth to this one. Lithium-ion batteries — the kind that power modern phones, tablets, and other smart devices — don’t suffer from the so-called “memory effect” that beset old Nickel-cadmium (NiCd) and Nickel-metal-hyrdide (NiMH) batteries.

The “memory effect” was said to kick in when you started charging a battery before it was completely empty. By doing that, you’d essentially reset how much charge the battery would think it could hold. So if you started charging a battery at 50 percent, the next time it got to 50 percent it would think it was empty.

There’s been plenty of debate over the years about whether that memory effect was a real thing or if it’s just an old wives tale that somehow became accepted as fact. But whatever its merits, it doesn’t apply to the lithium-ion batteries that power your gadgets today.

Verdict: MALARKEY.

3. Charging your phone kills its battery over time

This one is true, but with a caveat. The fact is, lithium-ion batteries do lose the amount of power they can hold with each charge cycle. But as Apple explains, a charge cycle has nothing to do with how often you charge your battery. Rather, it’s actually how often the battery discharges 100 percent.

So let’s say you discharge your phone’s battery by 50 percent one day then recharge it overnight. The next day, you do the same thing again. Those two days of discharging half your battery’s power adds up to one charge cycle.

So, yes, your battery will lose capacity over time. But not as quickly as you might have thought.


4. Don’t use your phone when it’s charging

This myth purports that, if you use your phone while it’s charging, you’re going to get electrocuted. But that’s simply not going to happen.

The only reasons you might really be electrocuted is if (a) you’re charging your phone while using it in the bathtub or (b) you’re charging it with some kind of cheap, knock-off charger (for more on those, see the next one).

But if you’re sitting at your desk and texting or talking on the phone while it’s charging using the charger it came with (or a reputable replacement), you should be absolutely fine.

That said, if you need to charge your phone quickly, your best bet is to leave it alone while it’s plugged in. That’s because the longer the screen is on, the more power it will use and the longer it’ll take to get fully juiced.


5. Using third-party chargers will ruin your phone’s battery

There’s actually a bit of truth to this myth, though it has to do more with knock-off chargers (i.e. those made without the original manufacturer’s blessing) than those made by third-party vendors (which meet the original charger’s specs).

If you buy a super-cheap charger online, and it’s not approved to work with your particular smartphone, it could in fact damage your phone’s battery, or even cause your phone to catch fire. But again, that’s only if you’re using an unlicensed knock-off charger.

If, however, you buy a licensed third-party charger from your local electronics store that’s compatible with your smartphone, you’ll be fine.


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