Take charge when buying a power bank

Take charge when buying a power bank

WHILE our smartphones and tablets are getting more advanced each day, battery tech has remained stagnant for years.

To mitigate this, device and platform makers have taken turns to come up with ways to prolong battery life, be it at the operating system level or at the hardware level.

To shorten charging wait times, we also have things like Qualcomm's Quick Charge and Oppo's "VOOC" rapid-charge technology.

Still, the improvements are inevitably negated as we do more on our devices. This is why many of us turn to power banks and battery cases.

Between a power bank and a battery case, my advice is pretty straightforward: The former is great if you don't want to bulk up your device all the time and you don't mind carrying a small brick with you; the latter is better if you're looking for an integrated protective case plus extra battery solution.

Here are some tips on what to look out for when buying a power bank:

KNOW YOUR DEVICE'S BATTERY CAPACITY

"How big a power bank do I need?" is probably the most common question I get. You first need to know your device's battery capacity.

Take the iPhone 6s, for example - it has a 1,715mAh battery.

But a 1,715mAh power bank might not be able to recharge it fully.

Due to voltage boosting and current conversion during the charging process, some energy is lost.

In my experience, the real-world conversion rate of power banks can vary between 60 and 75 per cent.

So, consider getting a power bank with at least 25 per cent more capacity than your device's battery. In the case of the 6s, get at least a 2,200mAh unit to ensure a full recharge.

FACTOR IN USAGE PATTERNS

A small power bank or battery case isn't useless. It really depends on your needs.

If you always end the day with 15 per cent left on your 6s, Apple's new Smart Battery Case may be all you need. Even if it can't charge the 6s from 0 to 100 per cent, you'll end the day comfortably with, say, 50 per cent of battery life left.

Of course, getting a high-capacity power bank has its advantages.

It enables you to charge your device many times over. If you always forget to charge your device overnight or are always on the go and a power outlet is hard to come by, it makes sense to get a bigger power bank.

Also, bigger power banks tend to come with more than one output port so you can charge more than one device at the same time.

TAKE NOTE OF CHARGING SPECS

The battery inside a power bank is only half the story; the other half depends on other features the maker has built into the device.

Here are three I pay attention to:

Power bank's output power

Many smartphone-oriented power banks have an output of 1A (over 5V), which is fine if your device accepts only up to 1A.

But many devices, like the newer iPhones and Android devices that support fast charging, are able to accept different current and voltage levels.

So, it's good to know how fast your device can charge, and find a power bank that supports this.

For iPhones and iPads, I suggest power banks that have 2.4A outputs; for Android devices, at least 1.5A.

If your device supports Qualcomm's Quick Charge tech, your fastest charge will come from a port that supports the respective Quick Charge standard.

The ability to work with higher currents and more voltage levels dynamically is basically Quick Charge's secret sauce. Power banks that support Qualcomm's fast charging tech will be quick to point it out on their packaging.

Power bank's input power

This refers to the power the power bank is able to accept when you're recharging it. The higher the input, the faster it'll recharge. This is more important if you have a high-capacity power bank.

For a 20,000mAh power bank with a 0.5A/5V input, it'll take two full days to recharge. So if you're buying a big power bank, make sure the input port supports at least 2A over 5V.

Some premium power banks also support Qualcomm's Quick Charge at its input port. This allows the power bank to recharge at an even faster rate, assuming a Quick Charge-compatible USB charger is used too.

Using a 20,000mAh power bank as an example, if it supports recharging at 2A but over 9V due to Quick Charge, it'll take just under seven hours to completely recharge.

Power adapter

Many power bank makers don't throw in a USB charger because you're expected to use the one that came with your mobile device. That's usually fine as many smartphone and tablet USB chargers today are capable of 2A at 5V.

The problem is not all USB chargers are the same and many people make the mistake of using very old USB chargers to charge their power banks.

If your power bank takes forever to recharge, what you can do is check if your USB wall charger is providing sufficient power. Charging a power bank through a computer's USB port is also not advised, unless you're geeky enough to know and ensure that it's providing sufficient power.

LITHIUM ION OR LITHIUM POLYMER?

Should you buy power banks with lithium ion batteries or lithium polymer ones? It doesn't matter.

While there are charging and discharging differences between the two, they are, for the most part, indistinguishable to end users.

Some people may argue that thin, lithium polymer batteries in a softer case are more dangerous than lithium ion batteries encased in a harder shell.

But manufacturers have measures to reduce safety risks, whether through improving the electrolyte used (for lithium polymer ones) or via better safety mechanisms and power bank case designs.

It's not so much what type of battery is used but who makes it.

PAYING MORE FOR QUALITY AND SAFETY

Since batteries can explode, some power bank makers will tell you (usually on the packaging) where they source their batteries from. Such disclosures are welcomed but the battery is only one of the many components in a power bank.

The design of the circuit board, the quality of the chips used and how safety mechanisms are implemented also play a role when it comes to safety.

Unfortunately, while there are hundreds of power bank makers out there, only a handful are forthcoming.

If you aren't the technical type, the simplest way is to just buy from brand names or reputable vendors with proven track records.

If there's an unfamiliar brand you wish to try, at least do some research on the Internet to see if there's any feedback from other users.

Also, when something sounds too good to be true, it usually is. There are decent and cheap power banks out there, such as those from Xiaomi, but for such power banks, some features are left out to keep the price down.

If you see a $20 power bank that claims to have a 20,000mAh battery, two smart 2.4A ports and one Quick Charge 2.0 port, and is as thin as a pencil, let me know - I'll be more than happy to unmask the fake unicorn.


Visit Hardware Zone for more stories.

This website is best viewed using the latest versions of web browsers.