Anker 521 portable power station review
256Wh of LiFePO4 in the cargo area, and an honest look at whether a delivery driver has any use for it.
A 256Wh LiFePO4 power station with two AC outlets, a 60W USB-C port, two USB-A ports and a car outlet.
Check price on AmazonSpecifications
| Spec | Detail |
|---|---|
| Capacity | 256Wh |
| Continuous output | 300W |
| Peak output | 600W |
| Cell chemistry | LiFePO4 |
| Ports | 2 AC, 2 USB-A, 1 USB-C (60W), 1 car outlet |
| Stated lifespan | Up to 10 years, per Anker's InfiniPower claim |
| Warranty | 5 years |
| Approx. price | Around $260 |
Specifications above come from Anker's published specifications. Treat pricing as approximate, since Amazon pricing moves.
What it does well
- LiFePO4 rather than standard lithium-ion, which is the single most important line on the spec sheet for something that lives in a car. It tolerates heat and cycle count far better.
- Two real AC outlets, so it runs things a car socket cannot: a laptop charger, a small fan, a heated blanket on a cold morning wait.
- A 5 year warranty, which is unusually long for this category and tells you what Anker expects the cells to do.
- Six ports means it charges the phone, the headset and the tablet at once, which is the actual daily use rather than the emergency use.
Where it falls short
- 256Wh is not much once an AC outlet is involved. It is roughly a laptop workday or many phone charges, and it is nowhere near enough to run anything that heats or cools for long. Anything with a heating element will empty it in under an hour.
- It weighs enough and takes enough cargo space to matter in a vehicle where cargo space is the constraint on how many packages fit.
- For the money, a delivery driver gets more practical value from a power bank plus a good car charger. This is a camping and outage product that happens to work in a car.
- Recharging it needs either mains power at home or a long stretch of driving on the car socket, and 12V charging on the car outlet is slow.
What owners report
Owner reviews are consistent that the 521 is the size most people should have bought instead of something bigger, and that the LiFePO4 chemistry is the reason they are still happy with it after a couple of years. Reports from people who use it for outages and car camping are the most positive and the most detailed.
The recurring complaint is the 300W ceiling. Owners repeatedly describe buying it and then discovering that the appliance they wanted to run draws more than 300W, and that the peak rating does not help with a sustained load. The second recurring note is fan noise under load, which is expected but catches people out when they try to sleep near it.
Who it suits
- Drivers doing long stacked days who want to run a laptop, a fan or a heated blanket during waits.
- Anyone who wants one purchase that covers car use and home outages.
- Drivers in climates where sitting in a stationary vehicle for an hour is genuinely uncomfortable.
Who should skip it
- Anyone whose only real need is a charged phone. Buy the Anker 737 and stop there.
- Drivers short on cargo space, which is most drivers in a small car.
- Anyone hoping to run a kettle, a heater or a compressor fridge for a full block. Read the wattage on the appliance first; the maths does not work.
Alternatives worth considering
Charges phones and most USB-C laptops, costs less, and lives in a door pocket instead of a cargo area. For the overwhelming majority of delivery drivers this is the right product.
Check price on AmazonIf the vehicle is running anyway, a strong car charger solves the same problem for a fifth of the price. It just does nothing when the engine is off.
Check price on AmazonThe built-in cable removes the thing that actually goes wrong, which is a cable left at home. Less capacity than the 737, but it is the one you will always have with you.
Check price on AmazonCommon questions
What can a 256Wh power station actually run?
Small electronics for a long time and anything that heats or cools for a very short time. A phone many times over, a laptop for most of a working day, a small fan for hours. A heated blanket, a kettle or a portable fridge will drain it fast or exceed the 300W limit outright.
Power station or power bank for a delivery driver?
Power bank, for almost everyone. The power station only wins when you need a real AC outlet away from the engine. Our power bank versus car charger comparison covers the cheaper end of the same decision.
Why does LiFePO4 matter for a car?
Heat is what kills batteries, and a parked car in summer is one of the harsher places you can leave one. LiFePO4 cells tolerate heat and repeated cycling much better than standard lithium-ion, which is why Anker can put a 5 year warranty on it.
Will it charge while I drive?
Yes, through the car outlet, but slowly. The 12V socket is current-limited, so treat driving as topping it up rather than filling it. Mains charging at home is the practical way to keep it full.
Is it worth it if I only do a few blocks a week?
No. Work out what a block nets you in the Flex earnings calculator. At a few blocks a week this is several days of profit spent on a convenience you will use occasionally.
Keep reading
- Power bank vs car charger for delivery drivers
- Anker 737 power bank review
- Amazon Flex earnings calculator
This review draws on published specifications, manufacturer figures and the consensus of verified owner reviews. We have not tested this product ourselves, and we say so rather than implying otherwise. As an Amazon Associate we earn from qualifying purchases.