What power banks are best for hiking in 2020?
Disclaimer: This guide is my initiative and isn’t requested by or paid for by any brand and I haven’t received compensation by anyone for it.
Power banks are a bit misleading. Ever notice that your 10.000mAh power bank doesn’t recharge your phone 3 times, even though it should have enough power? That is because it doesn’t have 10.000mAh available for your phone. Just knowing the mAh of a battery pack is like you’re trying to determine how long moving will take while only knowing how big your truck is and not how fast it can go. And even if you know the theoretical speed, you have to take into account red lights, traffic jams and bathroom breaks. This article takes does all that, so you can simply see the end result: what power bank gets me the most power for the least weight.
So, without further ado I present to you the best and worst performing power banks suitable for hiking. These are power banks with a maximum of 20.000mAh advertised capacity because more than that is seldomly needed. Some popular power banks aren’t on the list though, why not? Well because to give you a proper comparison I need to know the efficiency of the power bank and there aren’t many sites testing this reliably. So this is a merging of data available at Powerbank20.com, Hardware.info, Techtest.org and PCWorld.com.
The best in a weighted ranking
Out of ~85 power banks these score the best and worst. To come to this score I’ve taken into account the energy to weight ratio of the device, charging speed, discharging speed and the fact that a smaller capacity power bank needs relatively more material (casing, ports, chips, etcetera) than a larger power bank.
Energy to weight ratio
The most important metric to calculate the score of a power bank is its energy to weight ratio. To come to this we need to follow a couple of steps, first we need to calculate the actual capacity available to you in a power bank. So I’ve got this analogy, it isn’t 100% correct but will do the job. Like I said earlier lets say the mAh of a power bank is the capacity of a truck. In that case the speed of the truck is Voltage. The Li-ion batteries in these power bank are 3.7V. But USB ports require you to travel at 5V. If you want to go faster you need to streamline your truck, now it has less capacity but can go faster. So 10.000mAh at 3.7V becomes 7.400mAh at 5V.
That 7.400mAh is the theoretical capacity it can transfer to your phone, that is already a loss of over 25% compared to the advertised capacity! Now comes the next step, efficiency. The circuit in you power bank that converts the voltage isn’t 100% efficient. Some capacity will get lost along the way. Bad circuits lose over 30% of the power in this process while awesome circuits only lose a couple percent. If we combine the theoretical capacity and the efficiency we get actual mAh available to you. So the most efficient 10.000mAh power bank in the chart has an output 7200mAh while the worst one barely provides 5000mAh. A huge difference! Now if we divide the Watt hour we can derive from this by the weight of the power bank we get Wh/kg or simply said: an energy to weight ratio.
The best small power banks
Small <7000mAh power banks are great if you are just out there for a couple of days maximum and need it just to power your phone for some navigation and photo’s on airplane mode, and perhaps an occasional head light or satellite communicator. These power banks will never provide the best energy to weight ratio because you need – relative to larger capacity power banks – still a lot material for housing, you still need a circuit, ports, lights, etcetera. But in the end they are still lighter than larger power banks so if you simply don’t need the extra capacity, go for a small one in this category.
Remarkable in the small power bank category
There aren’t that many small power banks out there that have been tested at the required 2A for this article so the differences are huge here. And the bottom half is probably not worth your consideration. The Anker PowerCore II 6700 comes out on top here with the RAVPower 6700 RP-PB060 behind but that one is only 17th overall in the ranking. Am I making it too difficult for these small power banks? I don’t think so, the RAVPower is very light but hasn’t got a great circuit and its efficiency is only 76%. If it had and efficiency around 95% like the top contenders in the other categories it would end up in first place here!
Other then that we see the Omars 5000. It is a bit heavier but still light and recharges 50% faster than the Anker and RAVPower so it is back at 75% capacity in about an hour, which is great if you just have a short stop at a restaurant or in a town. Another one worth mentioning here is the Apollo Traveller 5000. Heavy, very heavy for its capacity, you can easily get double the mAh for the weight. But it does have an enormous potential for charging speed. With a 60W charger it is back at 75% in about 15 minutes! Now a 60W charger is very heavy and not really suited for hiking. But with a small 30W Anker PowerPort Atom PD 1it is still ready to go in 30 minutes. For some that might be worth the weight penalty.
The best medium size
These are probably best suited for most hikers, with an advertised capacity of between 7.000mAh and 14.000mAh you can probably keep your phone, headlight, satellite communicator and headphones running for a week if you’re careful (flight mode, etcetera). The best of these offer a lot more capacity than the small power banks for just a little bit of extra weight. And it usually comes with benefits like pass through charging which allows you to charge both the power bank and your devices at the same time, several ports, and both high speed charging and discharging.
Remarkable in the medium power bank category
There are a lot of good options here. We see a couple of famous names like Anker, RAVPower and Xiaomi but at the very top there are some lesser known names. But one stands above the rest head and shoulders regarding the energy to weight ratio; The Nitecore NB10000 with its carbon fiber housing and efficient circuit just leaves the competition in the dust. The Tecknet, Charmast and Silicon Power are all very good power banks, light and efficient which gives them a great energy to weight ratio but they are simply outclassed by the one company that truly focused on creating an ultralight battery pack. Remarkable is that all power banks in the top here have 10.000mAh advertised capacity and offer fast charging at around 18W.
The best large power banks
This category of up to 20.000mAh advertised is for hikers who go longer stretches without power and might have extra's like a camera to recharge, listen to a lot of music and film often. Or simply for those who want to be sure they've got enough juice in colder environments or more unpredictable parts of the world. The top contenders here offer the best energy to weight ratio of all power banks suitable for hikers. They also tend to have higher input and output wattage for faster charging and enough ports to charge everything you need, even all together.
Remarkable in the large power bank category
The first thing to notice here is that the Charmast and Silicon Power at the top appear to be the same power banks, just like in the medium category. And again they score great. Very lightweight and efficient. A possible downside is that with 18W recharge speed they still need quite some time before they are ready to go again, over three and a half hours to get back to 75%. If a fast recharge is your top priority take a look at the Xiaomi Mi 3, Blitzwolf and Elecjet. All three can get you back on the road in less than two hours. The Xiaomi and Elecjet could potentially even do this in one and a half hour but that requires you to take a 45W charger that is both larger and heavier. Realistically most hikers will choose for something lighter like the Anker 30W PowerPort Atom PD 1 with these power banks which puts them on an even level.
How everything is calculated
- ((Advertised capacity in mAh * 3,7) / 5) * Efficiency
This is one of the most important metrics that are usually not visible when you look for a new power bank: how much of the advertised capacity can actually be transferred to my phone. First we want to know the theoretical number. So we take the advertised mAh and multiply it by the voltage for which this actually is the mAh. With Li-ion batteries this is 3.7V. Then we divide it by the voltage that is used for the output, and that is 5V for USB ports. That means a 5.000mAh power bank can theoretically put 3700mAh in your phone. A 10.000mAh has 7400mAh, and a 20.000mAh power bank 14800mAh so we are left with Theoretical output * Efficiency.
But that is just theoretical output. The circuit that converts the electricity from 3.7V to 5V isn’t 100% effective and you will lose some power along the way. That is why we need to know the efficiency of a power bank. I don’t own all these power banks myself and don’t have the measuring equipment, so I rely on external data from Powerbank20.com, Hardware.info, Techtest.org and PCWorld.com. To get consistent data these sites test the efficiency at a certain output. For years the standard has been 5V at 1A. That means a discharge speed of 5W. But these days barely anyone uses these very slow speeds anymore so testing the efficiency of a power bank at these speeds don’t represent real world usage. So I’ve only included power banks that have been tested at 5V at 2A, so 10W, double the speed. And the differences are quite big. For example the famous Anker PowerCore 20100 has an efficiency of 91,6% at 5W, which is great, but drops down to 70% at 10W! A lot of the circuits in older power banks were designed to be efficient at lower speeds and lose a lot of efficiency when you use Quick charge or a similar technology. That also means that some of these power banks that are able to discharge at much higher speeds, like 30W, might be more or less efficient at those speeds.
Energy to weight (Wh/kg)
- ((Output mAh * 5) / 1000) / Weight in kg
Now that we know the actual output of a power bank we can calculate the most important metric for this article: how much power do I get for the weight? First we want to get away from mAh because as we’ve seen it is dependent on other metrics. So by multiplying the output mAh with the voltage for which this is true, 5V, and dividing the outcome by a 1000 we get Watt hour. An independent metric that always works and can be easily compared. An iPhone 11 has a 12Wh battery, a Macbook Pro 16″ has 100Wh and and cheapest version of a Tesla Model 3 has 50.000Wh (50kWh). Now we’ve got Wh / weight in kg so we divide the Wh by the weight of the power bank in kg to get Wh per kg.
The great thing about this metric is that there are several ways to achieve this. One power bank might get a high Wh/kg by using a thin and light shell material while another uses a very light (but not very efficient) circuit or the other way around; take a small weight hit but have a very efficient power bank. Whatever their choice, the Energy to weight metric simply shows you; how much power does this power bank pack for its weight.
- (Energy to weight + ((Charge speed * 2) + (Discharge speed / 2)) – ((Advertised mAh / 1000) * 3,5))
The Weighted ranking is of course the most controversial, because it is simply an arbitrary rating I came up with and not an objective point of measurement. Basically it consists out of four parts. The most important one is logically the first; Energy to weight. Then comes a combination of how fast can you recharge the power bank and how fast can the power bank charge your electronics; ((Charge speed * 2) + (Discharge speed / 2)). Out of these two the speed of recharging is a lot more important than the speed of discharge. Simply because the second one doesn’t matter as much while hiking. You often have limited time in town so getting your power bank filled up again while having lunch or being in town for a couple of hours is great and very helpful. But it doesn’t matter that much if your phone takes 2 hours or 6 hours to recharge fully at night while laying in your tent. The last part; ((Advertised mAh / 1000) * 3,5)), is a penalty for power banks with more capacity. You need relatively little extra shell material for more capacity, small power banks still need input and output ports, indication lights, a conversion circuit etcetera. So if you don’t compensate for capacity the smaller power banks will always lose from larger power banks.
By taking all these factors into account we get a ranking that provides a good indication of which power banks might be interesting for hikers, and which aren’t.