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Anker 535 PowerHouse vs Anker 521 PowerHouse

Side-by-side on the specs that decide it — surge, capacity, runtime and price.

Both models' specs verified against manufacturer listings · Last updated

The short answer

Anker 521 PowerHouse costs $180 less. Whether that gap is worth closing depends on what you need to run.

⚠️ Before you buy

Neither of these will start a sump pump or well pump — both surge below the ~3,400W those motors need. If home backup with pumps is your use case, look at higher-surge models instead of either of these.

Anker 535 PowerHouse

A durable half-kWh unit for devices and light loads. Dependable, but the low output and slow charging make it a device-first companion.

Best for: Campers charging phones, laptops and lights, not appliances.

Where it falls short:

  • 500W output is device-scale
  • 120W solar input, slow recharge
Anker 521 PowerHouse

A pocket-scale LiFePO4 unit for keeping devices alive. 200W of output means it's a charger, not an appliance station.

Best for: Travelers and campers topping up phones, cameras and a laptop.

Where it falls short:

  • 200W output runs devices only
  • 256Wh is small
SpecAnker 535 PowerHouseAnker 521 PowerHouse
Price $429 $249
Capacity 512 Wh 256 Wh
Continuous output 500 W 200 W
Surge output 750 W 300 W
Battery LiFePO4 LiFePO4
Rated cycles 3,000 3,000
Weight (lighter wins) 16.7 lb 8.2 lb
Max solar 120 W 100 W
Recharge time (faster wins) 2h 30m 2h 30m

Runtime head-to-head

ApplianceAnker 535 PowerHouseAnker 521 PowerHouse
Refrigerator
Mini fridge13.8 hrs
Chest freezer
CPAP machine10.9 hrs5.4 hrs
Sump pump
Anker 535 PowerHouse
Price →
Anker 521 PowerHouse
Price →