3000Mah power bank. 3000mah power bank

Our favourite portable chargers and power banks rated and reviewed, plus an in-depth buyer’s guide

by Matt Jones

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In recent years, the rise of portable battery chargers or power banks has meant that heading into the great outdoors no longer means going off-grid. And being able to keep your devices charged even when you’re miles from the mains has some undeniable benefits. After all, a functioning phone can be a lifesaver in an emergency. We’ve tested ten of the best portable power banks and solar chargers for backpacking in a range of sizes and capacities. So whether you’re after a small, lightweight pal or a rugged, heavy-duty Hero, there should be something for you. This group test also includes three solar-powered chargers. These offer an alternative solution to the perennial power problem for adventurers planning to spend multiple days in the wilderness.

What Makes The Best Portable Power Pack?

Firstly, think about how much power you’re likely to need and how long you might be away from a power source. This will dictate what size power bank you need in terms of battery capacity, which is usually measured in milliamp hours (mAh).

To help you out, note that it typically takes 2,500 to 3,500mAh to charge a modern smartphone (though many factors can affect power consumption). Charging a GPS unit or digital camera is likely to consume a similar amount of power, while charging a head torch, smartwatch or GoPro will consume much less. High-powered devices like tablets and laptops are the biggest drain on battery capacity.

Put simply, the larger the rated capacity (in mAh), the more juice the power bank can store – though the trade-off is increased size and weight. So if you’re only carrying a smartphone on a day walk and just want a back-up power source, look for a.sized battery charger. On the other hand, if you’re planning to spend multiple days in the wilderness carrying a number of different devices (like a GPS, phone, GoPro and digital camera), then you’re going to need one of the bigger power banks around (probably 20,000mAh).

To power multiple devices effectively you’ll also need a power bank that supports simultaneous charging, i.e. one that has at least two or more outlet ports. Many of the latest models also offer features such as quick charging through high-speed USB or USB-C connectivity, as well as in-built technologies to prevent over-charging and optimise charging efficiency.

Durable Power Banks

Also consider your environment. In damp, humid conditions or on expeditions you might need a waterproof and rugged power bank, which can cope with moisture or even complete immersion as well as bumps and knocks. If so, look for a product with a certified IP (International Protection) rating, which is usually expressed as two letters or numerals, e.g. IPX6 or IP67. This standard classifies the degree of protection provided against intrusion, dust, accidental contact and water.

“It typically takes 2,500 to 3,500mAh to charge a modern smartphone”

As well as being impact and water-resistant, power banks specifically designed for the great outdoors often have LED lights, so they can be used as torches. This can be a useful additional feature, as can power banks with integrated charging cables – so you don’t have to remember to bring separate cables with you.

Other devices have integrated or add-on solar panels, which offer the ability to top up the power using energy from the sun. Solar panels are becoming more efficient all the time, meaning that this is now a viable option for those planning to spend days or even weeks off-grid. Most solar panels trickle-charge a power bank over a period of several hours, but others can also be plugged directly into your device.

GP Batteries Charge AnyWay

Price: £29.99 Weight: 224g Capacity: 10,400mAh Dimensions (L x W x D): 81 x 64 x 25 mm

One of the most innovative bits of outdoor kit we’ve seen recently, The Charge AnyWay from GP Batteries is a 2-in-1 battery charger and power bank. It comes with 4 x nifty RecyKo rechargeable AA batteries. These batteries can all be used separately from the power bank. That means that with the power bank and these batteries, you’ve got the versatility to charge your smartphone or battery-powered devices like a headtorch. It’s easy to use too, thanks to a dual color LED indicator that displays charging status. In-built safety protection offers security against overheating, overloading or short circuits.

Pros: Lightweight, versatile, easy to use and eco-friendly, since it uses rechargeable batteries rather than a lithium ion cell, and reduces your reliance on single-use AA batteries. Cons: Not the speediest. It takes about 6 hours to fully charge the supplied 4 x AA RecyKo AA batteries. It’s also not as quick as other portable chargers when used as a power bank due to the 1A USB output.

Biolite Charge 20

Price: £40 Weight: 166g Capacity: 5,200mAh Dimensions (L x W x D): 108 x 44 x 20mm

The smallest power bank on test, the Biolite Charge 20 weighs under 200g and slides easily into a It has a 5,200mAh capacity – enough for about two smartphone charges. It is easy to operate. There’s just a single button that lights up a four-LED indicator telling you how much juice is left. There’s one micro-USB input and one 2.1A USB output, offering fairly swift charging. The stainless steel housing is sleek and durable, while a flip-top lid helps to protect the ports from dirt and moisture. The Charge 20 has an IPX6 rating, offering resistance to rain and spills. It is supplied with its own charging cable.

Pros: Lightweight, compact and durable. Just slip it into a and head out into the hills for peace of mind, knowing you can keep your phone alive throughout the day. Cons: Single outlet port and limited battery capacity means this little guy reaches his limits when it comes to charging bigger devices.

Goalzero Venture 70

Price: £136.95 Weight: 485g Capacity: 17,700mAh Dimensions (L x W x D): 170 x 103 x 29mm

The Goal Zero Venture 70 is a seriously rugged, waterproof power bank with an IP67 rating. It has a fairly generous 17,700mAh capacity – enough to charge a smartphone five times (though the manufacturer quotes up to six charges). The two high-speed 2.4A USB outputs can charge two devices simultaneously.

The Venture 70 also has a Smart charge feature that can identify different devices. It then applies the fastest charging profile possible, without risk of overheating or overcharging. It also allows pass-through charging. That means you can safely charge devices from the power bank even when it’s plugged into the mains. We also liked the built-in 65-lumen LED torch, which has two brightness settings and three strobe modes, including SOS.

Pros: Packed with useful features and some sophisticated internal tech. The extremely rugged, waterproof housing with integrated cables makes the Venture 70 a very practical option for the great outdoors. Cons: It’s the heaviest power bank in this round-up, and also the most expensive. If you really want to get the best out of the product you’ll need to read the instruction manual. That explains how to initiate the Smart charge sequence whenever you plug in a device for the first time.

Zendure A6PB

Price: £80 Weight: 392g Capacity: 20,100mAh Dimensions (L x W x D): 168 x 85 x 28mm

Zendure’s A6PB cutting-edge power bank is equipped with USB-C and 3.0A USB outlet ports for Rapid charging of two devices simultaneously. It has a generous 20,100mAh capacity, enough to fully charge an iPhone X 5½ times. We found that real-world performance matched the manufacturer’s claims. It also offers pass-through charging. Auto-detection means that devices start to charge as soon as they are plugged in. Adaptive charging automatically adjusts the output to charge your device at optimum speed. The A6PD also has in-built protection against short circuits, power surges, overheating and overcharging. It comes with a protective cloth pouch and USB cable.

Pros: With the quickest charge times of any power bank in this round-up, the A6PD is ideal for those with the latest devices who need their juice fast. Cons: Although housed in an extremely rugged composite case, this power bank does not carry an IP rating and is not waterproof.

GP Batteries M-Series MP15MA

Price: £34.99 Weight: 347g Capacity: 15,000mAh Dimensions (L x W x D): 140 x 75 x 24mm

With USB-C and twin 2.4A USB outputs, the GP Batteries M-series power bank supports the latest devices and offers speedy charging. You can charge up to three devices simultaneously. The 15,000mAh capacity gives a real-world performance of about four to five smartphone charges (though the manufacturer quotes six). It’s very simple and easy to use – a single button with four LED indicator lights and device auto-detection means you can just plug in and go. It is supplied with a 2-in-1 micro-USB and USB-C cable.

Pros: Striking a good balance between capacity, weight and size, this is a versatile all-rounder at a competitive price. For us, it’s the best value option in this test. The triple outlet ports are very useful, while USB-C input/output supports the latest devices and permits Rapid mains charging. Cons: Though the case features anti-slip rubber coated edges that may help to absorb minor impacts, the power bank does not carry an IP rating. Nor is it supplied with a protective pouch.

Outdoor Tech Kodiak Plus 2.0

Price: £59.99 Weight: 290g Capacity: 10,000mAh Dimensions (L x W x D): 123 x 88 x 28mm

Thanks to its IPX7 rating, this power bank by Outdoor Tech can be submerged in 3ft of water for up to 30 minutes. That makes it well-suited to the most demanding conditions. It also has a built-in 100-lumen torch with three light settings – another useful feature for the great outdoors. The design is compact and relatively lightweight, while the 10,000mAh capacity gives you real-world performance of a little over three full smartphone charges. However, although there are two USB outlet ports, only one of these supports high-speed charging. The Kodiak Plus 2.0 does not have charge-through capability either.

Anker Powercore 20100

Price: £34.99 Weight: 353g Capacity: 20,100mAh Dimensions (L x W x D): 173 x 67 x 26mm

This slim-line power bank has two 2.4A USB outputs for high-speed charging, augmented by Anker’s PowerIQ Smart charge and voltage boost technology. This identifies your device and adjusts voltage output accordingly, while also compensating for cable resistance. It’s all intended to deliver the fastest possible charging speed, even when charging two devices simultaneously.

Real world performance was very good. The large 20,100mAh capacity gives five to seven smartphone charges, depending on the model. The Powercore 20100 also has built-in protection from power surges and short circuits. It comes with a micro USB cable and a travel pouch.

Pros: Slim design, simple to use and good performance. High battery capacity and competitively priced too. Cons: We wish it had a USB-C port. The only other real drawback is that the plastic case is not IP-rated against impact or moisture, meaning it’s not as tough as some other power banks we tested. Basically, don’t drop it or let it get wet!

Ravpower Xtreme RP-PB41

Price: £36.99 Weight: 459g Capacity: 26,800mAh Dimensions (L x W x D): 178 x 85 x 27mm

This Ravpower Xtreme power bank boasts triple 2.4A USB ports so you can charge three devices simultaneously at high speed. An impressive array of built-in technology protects against overheating, overcharging, short circuits and power surges. It also automatically adjusts charge output and voltage for optimum charging speeds. It’s incredibly simple to use, with a single button that displays a four-LED power indicator to let you know how much juice you have left. Not that you’re likely to run out, given the whopping 26,800mAh battery capacity. That gives you nine full charges for the iPhone X, which is impressive. It is supplied with a micro-USB cable and a travel pouch.

Pros: Huge battery capacity, multiple outlets, high-speed charging, easy to use and very well-priced. Cons: Inevitably, this power bank is fairly heavy. We also wish it had a USB-C port – though the latest 26800mAh Ravpower model (the PB058) has added this feature. Our only other negative is that this power bank isn’t IP-rated, so it isn’t as tough as some.

WakaWaka Power With Solar Panel And Link

Price: Power £49.99, Solar panel and link £79.99 Weight: Power 165g, Solar panel and link 751g Capacity: Power 3,000mAh, Solar panel and link max 10W output Dimensions (L x W x D): Power 125 x 83 x 21mm, Solar panel (folded) 170 x 170 x 28mm

A compact and lightweight power bank with an integrated solar panel that can fully recharge its 3,000mAh internal battery in 12-18 hours of sunlight. The WakaWaka Power has a single 2.1A USB output and a micro-USB input (so you can charge it from the mains too). In addition, the Power has a 70-lumen LED torch with four brightness settings and SOS mode. The 3,000mAh capacity gives you about 200 hours of light or one full smartphone charge, and charging speed is fairly swift. The power bank has a swivelling base that enables you to place it at almost any angle. This is ideal for positioning it as a camp lantern or adjusting the solar panel to ensure it is in direct sunlight.

To boost the capability, you can also add a separate folding solar panel with a max 10W output. It connects to the Power via a link box. This also has a second USB port so you can charge another device simultaneously. Setup is simpler than it sounds, and the Power’s LED indicators tell you how much juice it has left as well as how effectively it is charging from the sun.

Pros: It has a useful LED light and enough juice to give your smartphone a full charge. When coupled with the separate solar panel and link, its capabilities are drastically increased for off-grid trips. The 10W panel has a bigger output than any other solar charger we tested. Cons: The Power is obviously limited by its small 3,000mAh capacity, though WakaWaka also sell 5,000 and 10,000mAh power banks that are compatible with the solar panel and link. However, the key drawbacks of the system are cost and weight. Though it has a big 10W output, the solar panel is heavy, while the total cost of the Power, solar panel and link is nearly £130. And like all solar-powered systems, you’re obviously reliant on several hours of sunshine to get optimum results. The panel itself delivers solid performance though.

Freeloader Sixer Plus Supercharger Solar Panel

Price: Sixer £69.99, Supercharger £49.99 (or buy together as the Off Grid Adventurer bundle for £110) Weight: Sixer 250g, Supercharger 311g Capacity: Sixer 6,000mAh, Supercharger max 5W output Dimensions (L x W x D): Sixer 134 x 83 x 30mm, Supercharger 275 x 180 x 15mm

Another compact and relatively lightweight power bank with an integrated solar panel that can fully recharge its 6,000mAh internal battery in 28 hours of sunlight. However, with the Supercharger solar panel attached, charge time is reduced to around 8 hours, or 6 hours if all the solar panels are in direct sunlight. The Freeloader Sixer has a 2.1A USB output as well as integrated micro-USB and lightning cables, enabling up to three devices to be charged simultaneously.

Pros: Easy to use thanks to the LCD screen’s clear icons that indicate remaining battery life and charging source. We liked the integrated charging cables too. The 5W Supercharger solar panel is impressively thin and light. It also comes with Velcro straps to attach it to a rucksack. The solar cells are efficient enough to charge even in overcast conditions. That makes the system a good option for off-grid adventurers – provided you’ll see some sun. Cons: The integrated support stand used to position the Sixer is flimsy and snapped on test. Though marketed as impact- and water-resistant, it does not carry an IP-rating. It does have a rubberised cover to help protect against damage, but this needs to be removed to use the integrated charging cables.

Powertraveller Extreme Solar – Best In Test

Price: £115 Weight: Extreme 280g, Solar panel 284g Capacity: Extreme 12,000mAh, Solar panel max 5W output Dimensions (L x W x D): Extreme 140 x 78 x 28mm, Solar panel (folded) 275 x 180 x 15mm

This combination battery and solar charger kit consists of two components. There’s a 12,000mAh capacity power bank and a separate folding solar panel of clamshell design that delivers a max output of 5W. The power bank has a 2.0A USB output as well as a USB-C port and, uniquely among the power banks in this test, a 12V DC outlet. This makes the Powertraveller a versatile option for charging multiple devices quickly, from SLR cameras and GPS devices to the latest smartphones. It’s housed in a tough, rugged, waterproof case with an IP65 rating, meaning it is dust-proof and waterproof (though not immersible). The power bank also supports pass-through charging and is supplied with an array of cables to fit various devices.

The solar panel is compact and lightweight. It unfolds to 210 degrees and will charge in low light conditions. A flashing LED light shows green for optimum charging, red for lower-quality conditions. Handily it also comes with a Velcro strap that enables you to attach the panel to a rucksack.

Pros: Very versatile thanks to multiple outlets, including USB-C and a 12V DC output. Decent battery capacity gives up to five full smartphone charges. This is also the toughest solar charger on test, making it our preferred option for multi-day wilderness trips. Cons: Few drawbacks other than the standard proviso that applies to all solar-powered products – you’re obviously reliant on several hours of decent sunshine to get good performance. However, even when used as a standard power bank the Powertraveller performs extremely well.

Does a 3000 mAh portable power bank charge a 3000 mAh phone? Gary explains

If you have a device like the Samsung Galaxy S7, which has a 3,000 mAh battery, how much capacity do you need in an external battery pack? 3,000 mAh, right? Wrong! Let me explain.

Portable power banks (external battery packs) are a popular accessory for smartphone users. They are basically a big battery in a plastic case with a USB port. You can use them to recharge you smartphone when you aren’t near mains electricity or when you want to charge your phone while on the go. The main characteristics of a portable charger is its capacity, quoted in milliamp hours (mAh). The come in all shapes and sizes from around 2,000 mAh to 20,000 mAh and beyond.

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So if you have a device like the Samsung Galaxy S7, which has a 3,000 mAh battery, how much capacity do you need in an external battery pack? 3,000 mAh, right? Wrong! Let me explain.

Experiments

To see how much capacity is needed to recharge your smartphone we are going to need to do a little bit of experimentation plus some maths! First the experiments. I bought 3 portable power packs from Amazon: A 3,100 mAh Samsung Portable Charger, a 3,350 mAh PowerCore lipstick-sized portable charger from Anker, and a 16,100 mAh Amazon Basics portable power bank.

With each of the power packs fully charged I started charging some completely depleted phones and recorded how much each battery pack was able to deliver. For example I took the 3,100 mAh Samsung power bank and charged a Samsung Galaxy S7 from 0% to… Want to take a guess? The S7 has a 3,000 mAh battery and the 3,100 mAh battery pack can charge it to 71%. That is 2,130 mAh of charge.

I got similar results for the Anker PowerCore. It managed to charge a phone with a 2,850 mAh battery from 0% to 82%, that is 2,337 mAh of charge from a 3,350 mAh rated portable charger. As for the Amazon Basics power bank, I needed to charge several phones to empty this beast! It managed to charge the Sony Xperia X from zero to full, and then a Moto G from nothing to 100%, and then the Samsung Galaxy Note 5 from 0% to 100%, and then the Samsung Galaxy S7, and finally it charged the Note 5 (which I had drained) from 0 to 43%. In total it managed to output 12,380 mAh.

As you can see, none of the power banks are delivering their full capacity. Doesn’t matter if it is a small power bank or a huge one, none of them hit the advertised mAh capacity. Why is that?

The maths

Each battery pack quotes its capacity in mAh, however most of them also quote a second number, the watt-hours (Wh). You don’t often find it on the website selling the charger, but on all three I did find it on the label of the unit. For example, the 3,100 mAh (that is 3.1 Ah) Samsung Portable Charger has a capacity of 11.78 Wh. Remembering that a Watt is calculated by multiplying Amps by Volts, then how many volts is this battery? 11.78 divided by 3.1 is 3.8 volts. Performing the same calculation on the other power banks gives an answer between 3.6 and 3.8 volts.

Generally the batteries in smartphones and the batteries in power banks run at 3.7 volts. But here is the thing, USB ports and the charging circuits work at 5 volts. When you connect your smartphone to the USB power on the battery pack it is actually working at 5V, not 3.7V. To go from 3.7V to 5V some conversion is needed. Since the Watt capacity is fixed, then going from 3.7V to 5V will decrease the number of amperes that the power bank can supply. That means that a 11.78 Wh battery (3,100 mAh at 3.8V) can deliver 2,356 mAh at 5V.

But, when the electricity reaches the phone it is converted again, from 5V down to probably 4.2V or 4.4V. So a 11.78 Wh battery (3,100 mAh at 3.8V) can deliver 2,804 mAh at 4.2V. Each of these conversions to step up the voltage and then to drop it down again causes power loss, anywhere from between 8% to 25% (depending on the design and quality of the converter).

[related_videos title=”Gary Explains” align=”left” type=”custom” videos=”696393,695569,694411,691474,683935,681421,679133″]You will have noticed that your phone can become warm on the back while charging, that is partly the power loss during the voltage conversion. The actual efficiency numbers aren’t known (other than what we can find through empirical testing), as it depends on the battery pack and on the phone being charged.

The Samsung battery pack managed 2,130 mAh in testing, which is less than the theoretical maximum of 2,804 mAh (at 4.2V). Therefore between the battery pack and phone there is a loss of around 24%. There are other unknowns like the quality of the batteries in the power banks and the real capacity level of those batteries,

When the same calculations are performed for the Anker and the Amazon Basics chargers we get close to the observed results. Each phone and power pack will be slightly different in terms of its efficiency, for example the bigger Amazon Basics charger did better in terms of efficiency, but remember that I had to charge several different phones to deplete it, and each of those phones has its own charging characteristics. We can come up with an approximate formula like this:

To double check my results I hunted around on the internet for other examples of people charging their phones from portable power banks. From consumers asking why they didn’t see the full capacity of the power bank, to popular YouTube videos about battery packs, I gathered data and tested it against my calculations. The biggest unknown is the efficiency of the voltage conversion in the power bank and phone. However the formula above works… more or less!

Wrap-up

Of course when you are buying a power bank you might not have time to start multiplying capacities by 3.7 then dividing by 4.2 and then factoring in the efficiency etc. So here is my rule of thumb: a portable power bank will deliver about 2/3 of its advertised mAh capacity. So if you have a 3,000 mAh phone, you multiply by 3 (giving 9,000) and then divide by 2 (giving 4,500) to get the size of the battery pack you need for one charge. If you want 2 charges then double that, and so on.

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If you are being really lazy then just go with double, i.e. 3,000 mAh smartphone needs a 6,000 mAh battery pack for one charge. There will be some juice left over, but erring on the side of caution has its benefits.

One final thing, I would like to give a big shout out to Uki from the Android Authority forums who asked me this question a couple a months ago. Great question Uki, sorry it took so long to make the video about it!

What are your experiences with portable battery banks, do you get the same results as I do? Please let me know in the Комментарии и мнения владельцев below.

Does a 3000 mAh portable power bank charge a 3000 mAh phone? Gary explains

If you have a device like the Samsung Galaxy S7, which has a 3,000 mAh battery, how much capacity do you need in an external battery pack? 3,000 mAh, right? Wrong! Let me explain.

Portable power banks (external battery packs) are a popular accessory for smartphone users. They are basically a big battery in a plastic case with a USB port. You can use them to recharge you smartphone when you aren’t near mains electricity or when you want to charge your phone while on the go. The main characteristics of a portable charger is its capacity, quoted in milliamp hours (mAh). The come in all shapes and sizes from around 2,000 mAh to 20,000 mAh and beyond.

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So if you have a device like the Samsung Galaxy S7, which has a 3,000 mAh battery, how much capacity do you need in an external battery pack? 3,000 mAh, right? Wrong! Let me explain.

Experiments

To see how much capacity is needed to recharge your smartphone we are going to need to do a little bit of experimentation plus some maths! First the experiments. I bought 3 portable power packs from Amazon: A 3,100 mAh Samsung Portable Charger, a 3,350 mAh PowerCore lipstick-sized portable charger from Anker, and a 16,100 mAh Amazon Basics portable power bank.

With each of the power packs fully charged I started charging some completely depleted phones and recorded how much each battery pack was able to deliver. For example I took the 3,100 mAh Samsung power bank and charged a Samsung Galaxy S7 from 0% to… Want to take a guess? The S7 has a 3,000 mAh battery and the 3,100 mAh battery pack can charge it to 71%. That is 2,130 mAh of charge.

I got similar results for the Anker PowerCore. It managed to charge a phone with a 2,850 mAh battery from 0% to 82%, that is 2,337 mAh of charge from a 3,350 mAh rated portable charger. As for the Amazon Basics power bank, I needed to charge several phones to empty this beast! It managed to charge the Sony Xperia X from zero to full, and then a Moto G from nothing to 100%, and then the Samsung Galaxy Note 5 from 0% to 100%, and then the Samsung Galaxy S7, and finally it charged the Note 5 (which I had drained) from 0 to 43%. In total it managed to output 12,380 mAh.

As you can see, none of the power banks are delivering their full capacity. Doesn’t matter if it is a small power bank or a huge one, none of them hit the advertised mAh capacity. Why is that?

The maths

Each battery pack quotes its capacity in mAh, however most of them also quote a second number, the watt-hours (Wh). You don’t often find it on the website selling the charger, but on all three I did find it on the label of the unit. For example, the 3,100 mAh (that is 3.1 Ah) Samsung Portable Charger has a capacity of 11.78 Wh. Remembering that a Watt is calculated by multiplying Amps by Volts, then how many volts is this battery? 11.78 divided by 3.1 is 3.8 volts. Performing the same calculation on the other power banks gives an answer between 3.6 and 3.8 volts.

Generally the batteries in smartphones and the batteries in power banks run at 3.7 volts. But here is the thing, USB ports and the charging circuits work at 5 volts. When you connect your smartphone to the USB power on the battery pack it is actually working at 5V, not 3.7V. To go from 3.7V to 5V some conversion is needed. Since the Watt capacity is fixed, then going from 3.7V to 5V will decrease the number of amperes that the power bank can supply. That means that a 11.78 Wh battery (3,100 mAh at 3.8V) can deliver 2,356 mAh at 5V.

But, when the electricity reaches the phone it is converted again, from 5V down to probably 4.2V or 4.4V. So a 11.78 Wh battery (3,100 mAh at 3.8V) can deliver 2,804 mAh at 4.2V. Each of these conversions to step up the voltage and then to drop it down again causes power loss, anywhere from between 8% to 25% (depending on the design and quality of the converter).

[related_videos title=”Gary Explains” align=”left” type=”custom” videos=”696393,695569,694411,691474,683935,681421,679133″]You will have noticed that your phone can become warm on the back while charging, that is partly the power loss during the voltage conversion. The actual efficiency numbers aren’t known (other than what we can find through empirical testing), as it depends on the battery pack and on the phone being charged.

The Samsung battery pack managed 2,130 mAh in testing, which is less than the theoretical maximum of 2,804 mAh (at 4.2V). Therefore between the battery pack and phone there is a loss of around 24%. There are other unknowns like the quality of the batteries in the power banks and the real capacity level of those batteries,

When the same calculations are performed for the Anker and the Amazon Basics chargers we get close to the observed results. Each phone and power pack will be slightly different in terms of its efficiency, for example the bigger Amazon Basics charger did better in terms of efficiency, but remember that I had to charge several different phones to deplete it, and each of those phones has its own charging characteristics. We can come up with an approximate formula like this:

To double check my results I hunted around on the internet for other examples of people charging their phones from portable power banks. From consumers asking why they didn’t see the full capacity of the power bank, to popular YouTube videos about battery packs, I gathered data and tested it against my calculations. The biggest unknown is the efficiency of the voltage conversion in the power bank and phone. However the formula above works… more or less!

Wrap-up

Of course when you are buying a power bank you might not have time to start multiplying capacities by 3.7 then dividing by 4.2 and then factoring in the efficiency etc. So here is my rule of thumb: a portable power bank will deliver about 2/3 of its advertised mAh capacity. So if you have a 3,000 mAh phone, you multiply by 3 (giving 9,000) and then divide by 2 (giving 4,500) to get the size of the battery pack you need for one charge. If you want 2 charges then double that, and so on.

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If you are being really lazy then just go with double, i.e. 3,000 mAh smartphone needs a 6,000 mAh battery pack for one charge. There will be some juice left over, but erring on the side of caution has its benefits.

One final thing, I would like to give a big shout out to Uki from the Android Authority forums who asked me this question a couple a months ago. Great question Uki, sorry it took so long to make the video about it!

What are your experiences with portable battery banks, do you get the same results as I do? Please let me know in the Комментарии и мнения владельцев below.

Nomaday Power Bank

• 1 year warranty
• Fast delivery
• 14 days of return

3 000 mAh power bank LED indicator Built-in hook handle 2 ports: USB-A and USB-C

Material: zinc hook / aluminium body Suggested branding: silkscreen-laser Ø5.23 x 1.37”

EXTRA POWER, ANYTIME

The Nomaday Power bank is the battery boost you need while on the go. Enjoy convenient access to a 3 000 mAh capacity quick and powerful top up charge. Compatible with all USB devices.

MAKE AND SHAPE

Designed with a cylinder metal body in a convenient to carry size, the Nomaday Power Bank also includes an easy to use built-in clip. Attach it to your backpack, or shoulder bag and give your battery a charge while on your commute, or before jumping on a call. It’s designed to go with you for the day.

RECHARGE AND REPEAT

The LED indicator will let you know when it’s time to recharge your Nomaday Power Bank. Simply use the USB-C supplied cable to achieve a full charge in 3.5hrs.

Guillaume Delvigne

After graduating in 2002, he started his career with prestigious designers like George J. Sowden or Marc Newson. He evolves mainly in the fields of furniture, object, lighting and interior design.

Which MagSafe battery pack is best? 6 Expert Picks

ZDNET tested the best MagSage battery packs on the market to see which can best power your iPhone. Compare leading models from Apple, Anker, and more.

Jason Cipriani is based out of beautiful Colorado and has been covering technology news and reviewing the latest gadgets as a freelance journalist for the past 13 years. His work can be found all across the Internet and in print.

Lena Muhtadi Borrelli has several years of experience in writing for insurance domains such as Bankrate, allconnect, Healthline, Reviews.com, HomeInsurance.com, My Slumber Yard and MYMOVE. She is a financial expert who previously worked for Morgan St.

Sean Jackson is a creative copywriter living in Florida. He’s had work published with CNET, Realtor.com, theScore, ESPN, and the San Francisco Chronicle.

Jason Cipriani is based out of beautiful Colorado and has been covering technology news and reviewing the latest gadgets as a freelance journalist for the past 13 years. His work can be found all across the Internet and in print.

Lena Muhtadi Borrelli has several years of experience in writing for insurance domains such as Bankrate, allconnect, Healthline, Reviews.com, HomeInsurance.com, My Slumber Yard and MYMOVE. She is a financial expert who previously worked for Morgan St.

Sean Jackson is a creative copywriter living in Florida. He’s had work published with CNET, Realtor.com, theScore, ESPN, and the San Francisco Chronicle.

No matter how much Apple touts the longevity of the latest iPhone’s battery, users know it never seems to last all day.

Wireless battery packs that employ Apple’s MagSage technology offer an even more compact solution to the ever-helpful portable power banks, so you can ditch the wires entirely to power your iPhone 12-14 generation model on the go.- including the mini and Pro Max.

ZDNET went hands-on with the best and latest MagSafe battery packs on the market, testing them for efficient charge rate, portability, and charging pass-through capabilities to help you confidently decide which is the most practical and powerful option for your phone. Our first pick, the myCharge MagLock Magnetic Powerbank is budget friendly, has a built-in speaker that signals charge level and connection, and has a unique design that keeps the pack from overheating. Read on to see how other models compare and which is right for you.

myCharge MagLock Magnetic Powerbank

Best MagSafe battery pack overall

• Comprehensive functionality
• USB-C port
• Built-in speaker signals charge level and connection
• Budget-friendly

Features: Capacity: 3,000mAh, 6,000mAh, 9,000mAh | Charging Port: USB-C | Power button: Yes

The latest company to offer a MagSafe compatible battery pack is myCharge with its MagLock lineup. The MagLock lineup has three different options, ranging in capacity and price. A 3,000mAh option is 50, 6,000mAh is 60 and the 9,000mAh pack is 70.

The MagLock has a unique raised design where the pack connects to the phone. According to myCharge, the gap between the phone and the battery pack allows both devices to remain cooler than the competition, which leads to better efficiency and faster charging rates. When you connect the pack to your phone, it plays a short sound to let you know the pack is in use. Another sound plays when you remove the pack from your iPhone.

There’s also a power button, but I haven’t had to use it. I just attach the pack to my phone, let it charge, and then remove it. The MagLock is charged via a USB-C connection, and functions as a wireless charging pad if you place your phone on the pack while it’s plugged in.

Apple MagSafe battery pack

Best MagSafe battery pack for native integration

• Deep integration with iOS takes full advantage of the battery pack
• Smart charging ensures proper iPhone and battery pack charging
• Your iPhone uses reverse wireless charging to charge the pack
• Compact size

Features: Capacity: 1,460mAh/ 11.13Wh | Charging Port: Lightning | Power button: No

Apple’s MagSafe battery pack is the second smallest battery pack I tested, even though pictures can make it look big. Inside are two battery cells with 11.13 Wh of capacity. Don’t expect the battery pack to charge your iPhone from 0 to 100. Wireless charging is highly inefficient due to several factors (heat being one of them). You’re more likely to get around a 60% charge on the iPhone 12 Pro, and for most, that’s more than good enough to get through a long day at work or when traveling.

At 100, the MagSafe battery pack is the most expensive pack of the lot. Its tight integration can arguably justify Apple tax with iOS 14.7 and above; when you place the pack on a compatible iPhone, you’ll see an animation on your screen letting you know how much of a charge the pack has. It will automatically begin charging your phone. The first time you attach one to your phone, you’ll also see an alert letting you know it will keep your phone at 90% to protect your battery. The battery widget built into iOS will show the pack’s current charge level, right alongside your iPhone and other accessories.

Charging the battery pack is done via a Lightning connector on the bottom of the pack. If you use a 20W adapter, you can charge both the pack and the iPhone at the same time by plugging the connector into your iPhone. Your iPhone will then use reverse wireless charging to top off the battery pack.- the first time we’ve seen such a feature in use from any iPhone model.