Wattstanding
EcoFlow RIVER 3 Plus Smart Extra Battery (EFEB300)

Product image: EcoFlow

Expansion battery · EcoFlow

EcoFlow RIVER 3 Plus Smart Extra Battery (EFEB300)

EcoFlow · 286 Wh add-on

The short answer

The EcoFlow RIVER 3 Plus Smart Extra Battery (EFEB300) adds 286 Wh of storage. EcoFlow lists it at $159, about $556 per kWh.

Capacity
286 Wh
Chemistry
LiFePO4
Weight
7.7 lb
Price seen
$159

Good fit if

  • You already own the compatible base unit and need longer runtime
  • You prefer adding storage to adding a second station

Look elsewhere if

  • You do not own the compatible base unit
  • You need more output watts — an expansion battery adds energy, not power
$159EcoFlow listed price (base model) · seen 30 Sep 2026
View at EcoFlow

Every link opens the product page for this exact model. We may earn a commission; it never changes what we publish. Disclosure

What it adds

An expansion battery adds watt-hours to a compatible power station without adding output: the base unit's inverter still limits how many watts you can run, but you can run them for longer.

Practical noteWe could not match this battery to a station in our catalog from the listing text. Check the seller's compatibility list before buying.

Fit check before you buy

An expansion battery only works with the units its maker lists.

✓ Required? Check firsti Good to know
  • ✓Compatible base unitConfirm the exact base model and version with the seller.
  • ?Connection cableSome expansion batteries need a specific cable or adapter that may be sold separately.
  • iWeight7.7 lb as stated.

Specifications

Each figure is labelled with where it comes from. Numbered references link to the source list below.

Manufacturer storeRetailer listingWattstanding calculationNot verified

Published specifications

Battery capacity286 Wh[S1]Manufacturer store
Output (as stated)140 W[S1]Manufacturer store
Battery chemistryLiFePO4[S1]Manufacturer store
Weight7.7 lb[S1]Manufacturer store

Wattstanding calculations

Price per kWh$556Wattstanding calculation

Limitations to weigh

  • Specifications are the maker's or seller's; Wattstanding has not tested this product.
  • Compatibility is the seller's statement; confirm it for your exact base unit and version.
  • Prices change; confirm the price and what is included.

Alternatives worth comparing

Anker SOLIX BP1000 Expansion Battery - 1056Wh LFP (For C1000) (A17611Z1-85)1,056 Wh; $221 more
VTOMAN LIFEBMS 1548Wh Extra Battery for FlashSpeed 1500/1000/6001,548 Wh; $221 more
Dabbsson DBS1700B Expandable Battery1,700 Wh; $540 more
EcoFlow DELTA 3 Max Plus (2048Wh) Smart Extra Battery2,048 Wh; $700 more

Where to buy

Our link opens this exact product page. Prices and stock change; check before you order.

$159EcoFlow listed price (base model) · seen 30 Sep 2026
View at EcoFlow

Every link opens the product page for this exact model. We may earn a commission; it never changes what we publish. Disclosure

Questions buyers ask

Will the EcoFlow RIVER 3 Plus Smart Extra Battery (EFEB300) work with my power station?
Check the seller's compatibility list for your exact base model.
Where can I buy the EcoFlow RIVER 3 Plus Smart Extra Battery (EFEB300)?
1 seller list it: EcoFlow.

Sources and verification

  1. EcoFlow — EcoFlow RIVER 3 Plus Smart Extra Battery — product page and specifications Retrieved 30 Sep 2026

Wattstanding has not tested this product hands-on. This reference is compiled from the sources above; our calculations are labelled and show their working. Electrical work belongs to a licensed electrician. Last verified 30 Sep 2026. How we work