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Research: Smartphones with the best batteries

Smartphone technology is always marching forward, progressing rapidly with new hardware improvements with each iteration and model revision.

Faster processors, infinity displays, better cameras, waterproofing, facial recognition — the list goes on.

But what’s the use of having all these fancy features if your smartphone battery can’t even last through a full day?

Thankfully, smartphone makers are already making strides in improving battery life. How? By optimizing software and by sticking in a bigger battery, of course.

Here’s our list of the best smartphones that can last you for a full a day and more with just a single charge.

iPhone 8 Plus

The iPhone 8 Plus may not have the largest iPhone battery around but it has the longest battery life among the current crop of iPhones, trumping the iPhone X, the iPhone XS and even the iPhone X Max.

It’s likely due to its smaller LCD screen and hardware/software optimizations that pushes it ahead of Apple’s flagship smartphone.

The iPhone 8 Plus can last up to 13 hours of internet use compared to 11 hours on the iPhone X. This means it typically lasts a full day of heavy use on a single charge. And like the iPhone XS Max, the iPhone 8 Plus (and the iPhone 8) also supports quick charging and wireless charging.

The battery life difference may not be significant but the price is. Unlike the iPhone XS Max, which starts at $1099, a brand new iPhone 8 Plus starts at $699.

iPhone XS Max

If you’re looking for a newer Face ID-enabled iPhone then the iPhone XS Max has the best battery life among the latest iPhone models.

With its more efficient A12 Bionic chip and larger battery, it can last longer than both the iPhone X and the iPhone XS, good enough for a whole day of use.

It still can’t beat the older iPhone 8 Plus in terms of battery capacity though and it’s super pricey at $1099.

Razer Phone

The Razer Phone is a premium Android smartphone meant for high-performance gaming on the go. As such, it has fancy buzzwords typically meant for the home theater — high-end Dolby Atmos sound, a 120Hz ultra-motion screen and support for Netflix’s 4K HDR and Dolby Digital Plus formats.

Powering all this goodness is a large 4,000mAh battery. However, to take advantage of this extra juice, you’ll have to tone some of its nicer features down a bit. Limit its display refresh rate down to 60Hz and you can squeeze out around two days of normal usage out of this beast.

You can get one of the best multimedia experiences on the go with the Razer Phone for around $699.

Samsung Galaxy Note 9

Now, here’s another smartphone with one of the biggest batteries ever. The Samsung Galaxy Note 9’s whopping 4,000mAH battery is much bigger than the Note 8’s 3,300 and combined with a much more efficient processor, it can last hours longer between charges.

The Note 9 can take around a day and a half of normal usage and you can probably push it to more than two days if you tweak its settings. It also supports fast charging and wireless charging so you won’t be left without juice for long.

Cramming a 4,000mAH battery in the Note 9 is a bold move from Samsung in light of the whole Note 7 battery recall fiasco but so far, so good — it looks like the company has figured it out.

Motorola Moto Z2 Play

The Motorola Moto Z2 Play is a mid-tier Android smartphone with a 3,ooomAh battery. Its specs are not exactly impressive, what with its 5.5-inch screen, lack of wireless charging and a middling Qualcomm Snapdragon 625 processor.

But for what it lacks in bells and whistles, it makes up for it with its impressive 31-hour battery life.

If you’re looking for a no-frills budget phone that can last you a day or two, then the Moto Z2 is worth a look.

Cat S61

When it comes to ruggedness and durability, CAT is making a name for itself with its line of shock-resistant, dust-resistant and waterproof Android smartphones.

While its flagship CAT S61 smartphone boasts unique features like a thermal imaging camera, a laser-assisted distance measuring tool and a built-in indoor air quality monitor, it also has a big 4,650mAh to juice it all up.

With this kind of power, this smartphone can last around two days of normal usage on a single charge.

The CAT S61 may not come cheap at around $999 but it has many functions that you can’t find on any other smartphone. It’s certainly worth a serious look.

Moto E5 Plus

Don’t let the Moto E5 Plus’ bargain bin price fool you, it has a massive 5,000mAh battery, one of the largest ones around. This can definitely last you for around a day and a half of heavy use.

It also supports quick charging so you can top it off with extra hours of usage with just 15 minutes of charging.

The Moto E5 Plus other specs are decent too — a large 6-inch HD display, 12MP rear and 8MP front cameras, 3GB of RAM and 32GB of storage.

For around $210, the Moto E5 Plus is one of the best budget smartphones out there.

Blackberry Key2

If you fancy having a good old hardware QWERTY keyboard on your phone, with a superior battery to boot, then the Blackberry Key2 is worth a look.

Although it carries the Blackberry pedigree, the Blackberry Key2 is actually manufactured by TCL under the name “Blackberry Mobile.”

The Key2 is an Android handset rocking a powerful quad-core Snapdragon 660 processor juiced up by a large 3,500mAh battery, enough to run it for around 25 to 35 hours before charging. It also has Qualcomm Quick Charge 3.0 support, good for squeezing hours of use with just 15 minutes of charge time.

Check out the Blackberry Key2 now for around $650.

The dos and don’ts of battery charging

To extend the longevity of your smartphone’s battery, here are a few dos and don’ts of battery charging you may not know about.

1. Don’t let your phone drain down to zero

To make your smartphone’s lithium-ion battery last longer, do not to drain it down completely.

Lithium-ion batteries don’t have the “memory effect” that older nickel batteries were prone to have. Nickel batteries had to be drained completely because they tend to forget part of their total capacity if they’re not down to zero before recharging.

In lithium-ion batteries, it’s the exact opposite. If you drain a lithium-ion battery down to zero, you are actually diminishing its capacity so it is advised to actually manually turn your phone off before it “dies.”

2. Do maintain your battery charge level between 40 percent and 80 percent

The ideal charge level for a stable battery is in the upper mid-range. Keeping a battery between 40 percent and 80 percent charged as often as possible will help you get the most out of its lifespan.

This is because a battery containing a higher voltage is under considerably more stress, and stress can potentially have degrading effects on the overall battery life by wearing down the battery’s internal chemistry.

3. Do unplug once it’s fully charged

The myth that overcharging the battery once it is already at 100 percent will damage it is actually partially true.

Modern batteries have mechanisms in place that prevent additional voltage once a battery has reached its maximum charge. However, there are what are known as “trickle charges,” which continually seep into the battery to maintain its 100 percent charge level.

Holding a battery at 100 percent all of the time does place more stress on the battery overall, so it still may impact its overall lifespan.

4. Don’t charge your smartphone overnight

We’ve warned you about the dangers of overcharging your phone. This usually happens when we go to bed, plug our smartphones in then leave them charging overnight.

If you’re like me, there’s nothing like waking up to a smartphone charged to 100 percent, ready to take on the day’s work! But can this habit really diminish our smartphone’s battery capacity?

The good news is that modern smartphones have built-in chips that keep them from overcharging. They’re smart enough to stop taking in excess electrical currents once it reaches a full charge.

The bad news is that due to the inherent properties of lithium-ion batteries, smartphone batteries are gradually losing their capacity with each charging cycle. This is why people typically start noticing a significant degradation in their smartphone’s battery capacity after two years of constant discharging and recharging.

By keeping your phone on the charger overnight, every night, while you’re sleeping, you’re keeping it on the charger for about three to four months a year. This means, while plugged in, it’s always in a state of discharging and recharging, slowly using up another cycle.

5. Do store at 50 percent charge

If you’re storing your phone unused for an extended amount of time, it is advisable to keep the battery charged at 50 percent before turning it off for storage.

For even longer periods, they recommend turning on the phone every six months or so and plugging it in to charge it back to 50 percent.

Lithium-ion batteries apparently have a tendency to destabilize if left discharged for a period of time. If destabilized, a lithium-ion battery could exhibit the thermal runaway effect and explode.

Fortunately, modern lithium-ion batteries have built-in self-destruct mechanisms that will kick in before destabilizing. If the self-destruct circuit is triggered, however, the battery will never be usable again.

6. Squeeze more life out of your smartphone battery

If you want to squeeze more life out of your smartphone’s battery, it’s important that you wait until a certain percentage before plugging it in, unplug when it’s fully charged, resist charging it overnight and always store it at 50 percent.

7. Just make sure you have a portable way to charge your phone

Finally, portable chargers are always a good idea to have. No matter where you are, in the backyard, at the store, or camping, it can never hurt to make sure you continue to follow all the tips to maintain a healthy battery.

To learn what drains your phone’s battery life in the course of a day, check out this tip and solve your power woes!

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