The A2 from Zendure has sat at the top of our power banks chart for the past couple of years, with only Xiaomi's Power Bank Pro able to come close in terms of an all-round balance of value, design, durability, speed, pricing and extra features.

Now the A3PD takes its place, offering all the same great features of the A2 with the addition of 18W USB-C Power Delivery (for fast charging and recharging in as little as 3.5 hours), a higher 10,000mAh capacity in an equally portable shell, and a hot new colour option: Flame Red. (Also available in Black and Silver.)

The A3PD is naturally a little more expensive than the A2, but even at £49.99 from Amazon this power bank is unbeatable. It's currently out of stock, but worth waiting for.

Some of the features that make Zendure's power banks really stand out in this crowded market include their support for high-end features such as passthrough charging (the ability to charge your phone and the bank at once from the same power point), long-time standby (up to 95% of the charge will remain after six months on standby), plus incredible efficiency, promising up to 80% of the power is available for charging your connected devices.

The A3PD has a good-looking but, more importantly, crushproof casing that looks seriously tough. We have always loved the design of Zendure's banks, and the new red option is a refreshing break from the hundreds of silver and black plastic banks that pass through our Test Centre.

This particular Zendure model has three ports at one end, with one input, one output, and one that does both. Both Micro-USB and USB-C inputs are rated at 18W, while the full-size USB output is a Quick Charge 3 port that can also deliver 18W.

Four LEDs on its top surface show you how much power remains, and with a 10,000mAh capacity each one corresponds to roughly 2,500mAh (2,000mAh in real terms, since some power is lost during the charging process). Despite all this power it measures just 98x64x25mm and weighs a pocketable 195g.

Also in the box you'll find a sturdy USB cable with a split connector that lets you use either Micro-USB or USB-C. Zendure no longer supplies a carry case, though this power bank is tough enough that you never really needed one anyway.

Now that Xiaomi's power banks are officially available in the UK there is nothing better in terms of value, design and performance.

If you can find it then we recommend the Pro (USB-C) version of this power bank, which has a super-thin 12.58mm design and is clad in tough-feeling yet premium-looking matte-finish aluminium, in rose gold or space grey. It's a great fit in the pocket, with rounded edges that also make it feel great in the hand.

And it will deliver around 7,100mAh to your devices, which is good for two- to three full charges of your phone, at a crazy rate - 18W in and out, with passthrough charging.

If you can't find it then fear not: the Mi Power Bank 2 is a Micro-USB version of the same device, and it's easily available from stockists such as Amazon and GearBest.

It looks almost identical, with the same slick aluminium housing. It's a fraction thicker, at 14.1mm, and can also deliver an 18W output, but the input is rated at 15W and the actual output is 6,900mAh.

All three of these support a low-charging mode suitable for fitness trackers and other low-power tech. Simply double-press the power button to activate.

Currently out of stock at Amazon, but available for just £24.13 from Geekbuying, Tronsmart's PB20 is most definitely worth the money. With a useful 20,000mAh capacity and an informative LCD display there is little wrong with this charger.

The high capacity and 88% conversion rate leads you to be able to enjoy multiple charges from this power bank without its battery depleting. The battery will charge some phones up to five times before needing a recharge, including 3.5 full charges of a Samsung Galaxy S10 or 4.5 iPhone XS charges, making it an impressive device.

The Tronsmart offers 15W fast charging over USB-A or USB-C. There are three USB ports, with the USB-C port also acting as a second input, so you can fast-recharge the power bank at 15W or at 10W over Micro-USB.

There is also a nifty LCD display, which allows you to have an accurate idea of how much power remains - something that is rare for cheap portable chargers. This means you’ll always be able to tell how much charge remains on your battery, which I think we can all agree is very useful.

The Tronsmart is matte black but with a smooth texture, giving it a slick-looking design. Due to its capacity this battery is reasonably heavy (342g) and a little bulky at 137x68.5x26mm, so you may prefer to put it in a bag than slip it into your pocket. However, it weighs no more than is standard for other power banks of this capacity.

Tronsmart's Trim is an interesting power bank, shipping with what appears to be a lanyard but actually unclips to reveal a cable that is Micro-USB at one end and a flat USB-A at the other, making it easy to refill the bank wherever you are.

What's missing from the box is a USB-C cable, which is necessary if you want to take advantage of its 18W Power Delivery port. This is on both the input and output, which means recharging the bank will be much faster when you do so over USB-C rather than 10W Micro-USB. You can also charge your device while charging the bank.

It's worth pointing out that the full-size USB port is also capable of delivering 18W to devices that support it, while VoltIQ ensures it delivers the fastest possible charging speed for whatever you've got plugged into it.

You can use both the USB-A and USB-C ports at once, but the device's maximum output is 18W so neither will run at full-speed.

The Tronsmart Trim has a really nice design, rectangular but slim, at 144x70x12mm, and it weighs just 194g. The black casing has a matt finish that feels lovely in the hand (and not at all slippery), while a rose gold metal trim is seen around the edges.

There's 10,000mAh of juice inside the bank, which should equate to around 6,500mAh usable power.

It's available now from Amazon at £24.18, and ships with an 18-month warranty.

The Iceworks 7000 is a very similar setup to the Flux Charger below, with a lower price (£19.95 at Amazon) and easier availability, but just the one built-in cable.

The version we're testing is a USB-C model, with that being very much the standard for new Android phones today, but it does rule out iPhone users and those running older Android phones with a Micro-USB connection.

The Iceworks is a fast charger for your phone or tablet, with both input and output rated at 15W. The output is of the USB-C variety too, so you can use your standard phone charger to juice it up in around four hours, and it'll recharge while charging your connected phone.

Perhaps more interestingly, the USB-C input is also an output, so you can actually charge two connected devices at once if required.

The design is good, but while it's just 9mm thick it still feels rather large for a 7000mAh power bank (of which you'll see around 4,550mAh). It's taller and wider than our connected Galaxy S8 at 156x78mm, which makes it feel less comfortable when stashed in a pocket.

But assuming you'll be throwing this charger in a bag it won't weigh you down at 159g, and we like not having to carry separate cables. You don't really need it, but the mesh carry case supplied in the box is a nice touch.

Yet another 10,000mAh variation on the Anker PowerCore series is this Lite model. This one is a similar shape to the Slim, but with a textured top surface that aids grip in the hand and more rounded edges. Four LEDs are tucked away on the side and easy to miss.

It's exactly the same price, at £25.99/$33.99 from Amazon, and has the same usable capacity of around 6,500mAh. That's enough for two- to three charges of your phone, depending on the model.

Where this model differs is with its two inputs: one Micro-USB and the other USB-C (you can't use both at once, and it still doesn't support passthrough charging), making it easier to charge up the bank with whatever cable you have to hand (a Micro-USB is supplied in the box along with a cloth carry case). Both are rated at 10W, which is pretty fast.

This is not a PowerIQ 2.0 model like the Slim, which means it isn't able to match the output speed from a single chipset. This power bank's full-size USB output maxes out at 12W, which is still very fast, but it's not Quick Charge fast. 

One of many such devices now coming on to the power bank market, the 5,000mAh AirBank is able to not only charge a device attached using a USB cable, but it can also wirelessly charge compatible smartphones.

It has an interesting design with 12 rubber suckers (six on each side) to hold your phone in place, which makes it very practical but is easily caught on the lining of your pocket and, let's be honest, looks a little odd. Still, we can't complain it's just another boring black plastic power bank.

We'll see more and more of these wireless power banks coming on to the market, and at £49.99 (buy here) you will almost certainly be able to find cheaper - and faster - examples. 

The AirBank supports Qi charging up to 5W, which is painfully slow. Wireless charging has moved on since the days when this was the maximum possible, and many new flagship phones are beginning to follow suit.

If you can't bear to wait so long to charge your phone then there's also a full-size USB output rated at 2.4A, offering 12W charging for a connected phone. You could even charge two devices at once, although the capacity is not sufficient to fully charge more than one.

QDOS' AirBank will work with phones in their cases provided they are not more than 3mm thick, and at up to 6mm distance. Although it says the device must be plugged into a power source for wireless charging to work, we found it would wirelessly charge our phone when running on the battery too.

Aukey's 20,000mAh power bank is appealing for three reasons: its price, at £39.99/$39.99 from Amazon, its large capacity, and its number and variety of ports.

You get three full-size USB outputs, as well as a single USB-C. You can also use this USB-C port to recharge the power bank, which is the fastest method, or you can use a Lightning or Micro-USB input (the latter oddly hidden around the corner from the other ports), so it will work with whatever cable you happen to have to hand. For what it's worth a USB-C cable is supplied in the box.

This isn't going to be the fastest power bank for charging multiple devices, however. While the USB-C can output up to 3A (15W), the remaining three outputs must share the same amount between all three. So if you plug in three devices they are each going to charge at a slow 5W. Still, all those ports could prove very convenient if you have multiple devices.

And if you are charging more than one device then you're going to need lots of juice. With a rated capacity of 20,000mAh you can expect around 13,000mAh to be available to your devices. That might charge an iPhone seven times, or a typical Android phone four times.

Once depleted the large battery will take 10 hours to recharge, though you can continue charging attached devices in the meantime.

The trade-off for all this power is size, and this Aukey charger is huge. It's much larger than our phone at 200mm long and 96mm wide, though also reasonably skinny at 14mm. It's as heavy as it looks at 435g, and feels quite bulky.

The design is also rather basic, a matt black plastic slab with a shiny plastic bumper running around the circumference. The Aukey logo is printed on the front and four small LEDs are visible on the side to show how much power remains.

Another dual-input power bank is the A20 from Romoss. This 20,000mAh power bank has both Micro-USB and Lightning inputs, which makes it easier for iPhone users to recharge the bank without having to also carry around a Micro-USB cable.

The A20 was supplied to us from GearBest, a Chinese importer, where it costs £23.16/$29.26. That's actually a very good price for a power bank of this capacity, but we tend to refrain from reviewing power banks available only in China - they are so easily and cheaply available in the UK that it makes little sense to import them.

Available in rose gold or grey, despite its low price the A20 has a fancy aluminium coating that makes it feel pretty cool. But save for the design, Lightning input and capacity (of which around 13,300mAh should be available to your devices), there's nothing particularly exciting about this power bank.

There's no support for passthrough charging, which is on our list of must-haves for high-capacity power banks (especially given this one will take 13 hours to charge over the 10.5W input), and neither is it particularly fast. Though one of the two outputs is rated at 10.5W, the second is just 5W, and if you use both together that 10.5W is shared between the two resulting on slow charging from both.

Still, if needs must, this bank could potentially charge your iPhone seven times. Just be aware that with big capacity comes big weight: the A20 weighs a very noticeable 491g.

We've concentrated on standard USB power banks in this chart, but that's to ignore an entirely new category of devices that build in USB Power Delivery support. Power Delivery devices can output up to 100W, which means they are technically capable of driving a USB-C-powered laptop or games console.

Power Delivery chargers can be confusing, however, since not all make it clear in their marketing their exact power output, and some are a long way from that magical 100W. This is actually more important than most users will realise, too: a 29W power bank isn't going to charge a laptop that requires 45W.

It's no surprise that Power Delivery banks cost more than standard power banks, and that's why you'll find Zendure's offerings toward the bottom of our chart. Most users will not need to spend this amount on a power bank, but for those who do they make excellent purchases.

The A6PD (reviewed here) is a 20,100mAh power bank with a 45W output, usually available from Amazon for £69.99/$72.99. If this isn't enough juice then there's also the A8PD, which has a 26,800mAh capacity but slightly lower 40W max output. It costs £99.99 (also via Amazon). 

Aside from the capacity the two power banks also differ in the number of outputs they offer. While the A6PD offers a single full-size USB output, a USB-C input/output and a Micro-USB input, the A8PD has swaps the Micro-USB port for an additional three full-size USBs. It will charge in just five hours using a 30W USB PD charger.

In other respects the two Zendure power delivery banks offer all the things we expect from Zendure, including the crushproof casing, passthrough charger and higher-than-standard efficiency rating and standby.