Power Your Weekend with Durable, Smart Energy
The Anker 521 Portable Power Station (PowerHouse 256Wh) is your compact, long-lasting solution for off-grid power. Featuring Anker’s proprietary InfiniPower™ technology, this LiFePO4 battery station provides reliable power for 10+ years of everyday use.
Key Features
- Long-Lasting Battery: Equipped with a 256Wh LiFePO4 battery and InfiniPower™ tech, designed for 3,000+ charging cycles.
- High Output: 300W rated AC output with SurgePower up to 600W for powering small appliances and electronics.
- USB-C Fast Charging: 60W USB-C PD port enables direct charging for laptops and tablets—no bulky bricks required.
- Versatile Charging: 6 ports include 2×AC outlets, 2×USB-A ports, 1×USB-C port, and 1×car outlet.
- Ultra-Portable: Lightweight and compact, perfect for camping, road trips, or home emergency kits.
Technical Specifications
| Battery Type | LiFePO4 (Lithium Iron Phosphate) |
| Battery Capacity | 256Wh / 80,000mAh |
| AC Output | 300W (600W Surge) |
| USB-C PD Output | 60W |
| Total Ports | 6 (2×AC, 2×USB-A, 1×USB-C, 1×Car Socket) |
| Weight | Approx. 8.2 lbs |
| Color | Black |
| Charging Methods | Wall Outlet or Solar Panel (sold separately) |
| Connector Type | USB Type-C |
What’s in the Box?
- 1 × Anker 521 Portable Power Station (256Wh)
- 1 × DC Adapter
- 1 × Car Charging Cable
- 1 × User Guide
- 5-Year Manufacturer Warranty
Ideal For: Weekend camping, off-grid travel, emergency backup, CPAP machines, outdoor events, and powering sensitive electronics safely.
It’s a great little machine but don’t trust the indicator, it’s 40% off.
⚡ What Makes It Great:
Built to Last: With InfiniPower technology and LiFePO4 batteries, this thing is made for longevity. Knowing it’s built to last over a decade with daily use gives me peace of mind. You can feel the quality in the build too—it’s rugged, impact-resistant, and clearly designed for the long haul.
Perfect for Weekend Trips: The 256Wh capacity is ideal for recharging phones, tablets, portable lights, and even a mini fan or camera setup. I took it on a two-day trip and still had juice to spare.
USB-C Port is a Game Changer: The 60W PD USB-C port means no more bulky adapters for your laptop or other devices. Just plug and go. I use it for both my MacBook and my Switch—no problems whatsoever.
SurgePower Up to 600W: This was a pleasant surprise. The 300W rating with 600W peak support let me power a mini-fridge and an electric kettle (separately, of course) without issue.
6-Port Convenience: The mix of 2 AC ports, 2 USB-A, 1 USB-C, and a car outlet makes this incredibly versatile. Whether I’m charging a phone, running lights, or plugging in my camera gear, I’ve got plenty of options.
🔋 Final Thoughts:
If you’re looking for a true energy backup solution that’s also perfect for travel, camping, or emergencies, this is it. Anker knocked it out of the park with this one. I can’t imagine not having it now—it’s one of those purchases that feels instantly worth it.
Highly recommend it—no regrets whatsoever.
To spend even _less_ on this type of power bank, I would actually suggest considering a power station without a 120v inverter, like the C300DC or C200DC, which right now are $50 and $70 less than the 521, respectively.
At best, power inverters are around 90% efficient, meaning you waste 10% of your power converting from DC to AC. So you're much better off getting USB-C or 12V car adapters for all your stuff, you'll get longer use of your electronics, and a lighter power bank without a noisy inverter.
Tonight I heard a whirring noise from one of the boxes. When I picked it up, the box was warm. I took the power station out of the box and turned the "plug" button on and off a few times. As soon as the station was out of the box, it cooled quickly and the fan turned off automatically. But for a little while, whenever the plug button was "on", the fan started running again.
Apparently the automatic cooling fan had turned on while the station was inside the box. Since the packing material is a closed-cell foam material and it completely blocks the fan vent, running the fan just created more heat. The station tried to cool itself, and instead it made itself hotter.
I'm not sure why the cooling fan turned on. It was about 80 degrees in that room this afternoon. Maybe when I boxed it up last night I accidentally pressed a button, and the 80 degree room plus the warmth from the "on" plugs triggered the fan to run, which made the box even warmer, etc.? The station's power had dropped from 100% yesterday to 37% today so it must have been running for a while. Last night I thought I had all buttons turned off, but I could have possibly have bumped a button while packing up.
Long story short-- next time I'm double-checking that all buttons are off before closing the lid. I'll update this if it happens again, but wanted to take a moment to warn everyone else that this can happen.
Also, there is no power switch to let you know the unit is on or off. There is a switch to turn on and off the display, however it's not always functional, as i far as i can tell, once the unit has been sitting inert for a while. This is puzzling to me why this function was omitted. You can't tell if it's working sometimes or what the charge level is. Could be I'm confused, but that itself is a condition that may be noteworthy. It's not obvious or intuitive how to tell if the unit is functioning or charged unless you insert a plug into it, then notice the display. The instructions do not mention an on and off switch.
Keep in mind the corresponding carrying bag, a bit pricey for it's size, does not have room to accommodate the AC power adapter for charging the unit, and from pictures, it seems to have barely enough room to store the cables, much less any AC pigtails or AC adapters or 12V DC extension cables. I used a Canon DG200 gadget bag for cartage and storage. Works fine. Many are available as used on eBay as i write this review for less cost than the Anker bag.
Overall, i think it's a good unit, so i'm keeping it.
Now on to the design of this wonder. First, the cooling fan is pretty loud when it runs, but even worse it's inconsistent. Imagine watching a movie and it's silent, but then wrrrrrrrrr. A cheap 80mm computer fan would run off the native voltage and do a better job at cooling and being functionally silent, since you could easily tune it out.
Love the standard socket for 10 amps of 12v and the USB-C for 12 amps of 5v. Paired with the AC, this thing can be used with adapters galore to power practically anything on the go. But the 7909, Anker? Its a niche barrel adapter at best, and it's hard to find specific adapters that convert to it. The included socket to 7909 adapter means you can jury rig some charger out of the panel you have, but a banana plug, standard 5mm barrel, or even an SAE adapter would be so much more compatible with adapters and panels already on the market, especially at the simple 65w charging speed this model is limited to.
Other than those 2 design gripes, the rest is very easy to love. The thing looks amazing and sleek. It's got well more than enough power to do practically anything you like for a night or 2 of light glamping, or for a night of watching movies in a power outage. It's light enough to put in a backpack and not overall bulky for its power density. You could probably do a solid week of work on a modern laptop before needing to recharge this thing.
I got it to run my pellet stove during power outages, stove was rated at 15 watt so assumed it should. Was 80% charged when arrived, I topped it off using the ac charge cord in about 15 min. Display read 100% which I saw some reviews stating it only would go to 99%. I tried it on my pellet stove and it ran through the reset cycle just fine which had me excited. Then it would start but then shut off and start again over and over. Evidently the stove draws more on start than the 521 can handle, the stove didn't have any start up specs. I'm sure it would run it if it would start.
It's a well built, very portable battery pack so I figured I would keep it for internet/wifi backup and device charging as a ups taking advantage of the ability to charge while in use. Will update on how that works seeing some found issues with shut down while using it this way. If it does work I will probably purchase the anker solar panel for charging also which at this point is needed even though they say any panel can be used. You can if you can find the adapter to fit the 521 which it doesn't look available except with the anker panel at this point. I have looked some and so far only found the 8 mm which people say does not work.
Awesome for charging devices and running low Amp ac gadgets or lights for the price, runs a small fan fine.
Could stand faster charging in both ac and solar. Advertising is a little misleading as to what it will run which can make it a disappointing purchase. Will update on how it runs my gateway/wifi.
Update. It keeps shutting off when trying to run home wifi. Basically only good to charge devices and run lights.
I have been looking for a smaller "solar generator" that will be used daily to transfer solar power from my big, fixed, LFP battery - the later sits in my basement connected to panels on the side of my house.
Key features needed were easy to carry, relatively fast charging, pass-through charging, PD output - plus the standard AC, 12V, and USB outputs. The Anker fit all of these plus the LFP battery is an advantage for a unit that will get cycled many times a week.
I've had it for a week now, and it does basically do what I want, but it has limitations. The biggest is the lack of a real "off" mode: if I fully charge it and leave it in economy mode with all ports off it still uses 1 to 2% per day. My EcoFlow units and Jackery units have a true off and drop by less than that in a week. For that alone it drops 2 stars.
More minor concerns:
1. Max AC ouput is only 200W, so I can't run anything needing more than that. Many units, even with the relatively small battery in this unit, can put out more than that.
2. The max power input is about 65W (by solar, AC, or PD); yes, I can get around that by combining solar/AC with PD input, but I wish I could use higher solar input so I could get full advantage from at least a 100W panel.
Note that when looking at the solar input side I couldn't find anything about the max input voltage - while you can use a panel providing more current than the max input (it will only take what it can use) excess voltage can fry a unit. I looked in the manual and on the Web site and couldn't find anything. I sent an email to support, asking for the max VOC allowed, and their response was I could use a "any (12V-28V) solar charger with DC 7909 Male connector" - not a great response as a solar charger typically has a controller, which would conflict with the one in the unit, and there are lots of MC4 to DC7909 adapters available (and no mention that the voltage that matters is the VOC). Still, it means I can use my "12V" panels that have VOCs from 18V to 25V (a have a few panels) without problem.
So, for my purpose the unit is fine for what I paid ($209) but others may be better for your needs.
Final note: many focus on the 3000 cycles of the LFP over the 500+ cycles of a typical NMC unit, but for most this is irrelevant. Few will go through a charge cycle more than twice a week, which means 104 cycles a year or 5+ years to reach that 500 cycles, and even then, the battery doesn't die at 500 cycles, it just drops to 80% of the original capacity. Don't buy one just because it has LFP unless you charge through a cycle more than twice a week.
Update: I tried to charge it by solar for the first time today. I tried two different panels, both of which work with my Jackery 240, and neither worked with this unit. In one case, the jack that was tight in the Jacker wobbled in the Anker, so it may be a connector issue with both. I've contacted tech support.
I also saw some odd behavior with AC output yesterday: I tried to top up my EcoFlow unit from 75% to 80% for storage, plugging it in to the Anker. The EcoFlow was set to slow charge mode, so it should have pulled well under 200W, yet it just sat there clicking, unable to pull enough power to start. I was able to charge it with the 12V outlet from the Anker, but need to test the AC output more; maybe the EcoFlow pulled more than expected to start charging by AC.
Update 5/21. I can't charge this with solar. Tech support said I need a 7909 connector, not the 8mm one which is pretty standard - and they don't sell a cable for solar charging or have one to recommend. I bought an 8mm to 7909 adapter and tried that today: doesn't fit. So, the Anker is going back.
So much potential here, from a company that is normally great, but this one product is flawed.
Update 5/30. After a lot of communication with Anker tech support, they provided one of their solar panels to try. It is a nice panel and works well with their unit and with my EcoFlow unit. I think that the solar charging issue I have comes down to an oddity with the connector, and if you have the right adapter the unit charges well with solar (within the limits of the 65W max input). Their panel comes with the adapter, and I assume that such adapters will be more readily available soon.
So, if you don't need solar charging or either buy their panel or find the right adapter, it is a good unit. Not perfect because of the 65W solar limit and 200W max output, but pretty good, and it comes with great tech support. So my, my review goes up to 4 stars.
Update Sept 19, 2022: The unit has been in use daily, primarily to top up my phone, tablet, and similar things, plus to top up tool batteries by DC or AC output. Working fine. I did some capacity tests with a 70W bulb and was pleased to see that it has a pretty efficient AC inverter, with low power loss. Another positive: with the right adapter cable, I can reliably charge this at 65W by solar, in addition to DC and AC.
But a big negative: the display cannot track low power/USB usage. If all I do is use it for topping up phones and tablets by USB all week, it will stay at 99% and then switch off at zero. I don't see the same with problem with AC usage. (Recalibrating by a full charge, drain until power off, and a full charge, makes no difference.) Not a huge issue for me: when it dies unexpectedly from USB use I'll just use another battery unit while this one is being charged, but it is a problem.