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frontpageDavid_David posted Sep 01, 2025 01:15 PM
frontpageDavid_David posted Sep 01, 2025 01:15 PM

Costco Members: EcoFlow RIVER 3 Plus Smart Extra Battery (EB600)

+ Free Shipping

$256

$320

20% off
Costco Wholesale
25 Comments 11,197 Views
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Deal Details
EcoFlow via Costco Next has for Costco Members: EcoFlow RIVER 3 Plus Smart Extra Battery (EB600) on sale for $255.99. Shipping is free.

Thanks Community Member David_David for sharing this deal

Note: Need to be Costco member, logged into your account, and click thru to Ecoflow Costco Next Portal

About this Item:
  • Expand the capacity of the RIVER 3 Plus to 858Wh
  • An additional 140W of USB-C input and output option
  • Enjoy a wireless Pogo Pin connection—no cables or screws required
  • Reduce your load by using the Extra Battery independently

Editor's Notes

Written by citan359 | Staff
  • About this Deal:
    • Valid through 9/14, while supplies last.
  • About this Store:
    • If you don't have a Costco Warehouse Membership, you can sign-up here
    • You can view Costco's return policy here.
  • Additional Notes:
    • Please see the original post for additional details & give the WIKI and additional forum comments a read for helpful discussion.

Original Post

Written by David_David
Community Notes
About the Poster
Deal Details
Community Notes
About the Poster
EcoFlow via Costco Next has for Costco Members: EcoFlow RIVER 3 Plus Smart Extra Battery (EB600) on sale for $255.99. Shipping is free.

Thanks Community Member David_David for sharing this deal

Note: Need to be Costco member, logged into your account, and click thru to Ecoflow Costco Next Portal

About this Item:
  • Expand the capacity of the RIVER 3 Plus to 858Wh
  • An additional 140W of USB-C input and output option
  • Enjoy a wireless Pogo Pin connection—no cables or screws required
  • Reduce your load by using the Extra Battery independently

Editor's Notes

Written by citan359 | Staff
  • About this Deal:
    • Valid through 9/14, while supplies last.
  • About this Store:
    • If you don't have a Costco Warehouse Membership, you can sign-up here
    • You can view Costco's return policy here.
  • Additional Notes:
    • Please see the original post for additional details & give the WIKI and additional forum comments a read for helpful discussion.

Original Post

Written by David_David

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Top Comments

GoGo98102
481 Posts
193 Reputation
Are you comparing temu to Costco, from 7 months ago, AND a pricing mistake?

24 Comments

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Sep 03, 2025 03:34 PM
491 Posts
Joined Dec 2009
justwannaSep 03, 2025 03:34 PM
491 Posts
Quote from speedy777 :
This is not good price. I've seen this in store $220 few weeks ago. It is nice for charging phone, but not enough wattage for other appliances during an emergency. We need new battery technology that around 2000W and similar in size.
You are referring to a different product, the River 3 Plus Wireless. The product in this post is an add-on battery that connects to the bottom of the main unit and increases its capacity.
Sep 03, 2025 04:07 PM
219 Posts
Joined Apr 2015
clarkr32Sep 03, 2025 04:07 PM
219 Posts
In comparison this specific item is $400 on Amazon
Sep 03, 2025 04:37 PM
184 Posts
Joined Sep 2006
mer30Sep 03, 2025 04:37 PM
184 Posts
"For any items purchased on the supplier website, the supplier will ship, provide customer service and handle returns. Purchases at the supplier do not qualify for Costco Executive benefits and are not included in the 2% reward calculation."
Sep 03, 2025 04:53 PM
4,276 Posts
Joined Nov 2006
ZanthexterSep 03, 2025 04:53 PM
4,276 Posts

Our community has rated this post as helpful. If you agree, why not thank Zanthexter

Quote from Plutomania :
Quote from NE0tekk [IMG]https://slickdeals.net/images/misc/backlink.gif[/IMG] :
Quote from Plutomania [IMG]http://i.slickdeals.net/images/midnight/misc/backlink.gif[/IMG] :
Costco Next products don't carry Costco's guarantee. Each brand has different terms.
EcoFlow's Temu store is run by EcoFlow and shipped direct from EcoFlow, same as Costco Next.
Pricing mistake 7 months ago, or not, the EB600 a 572Wh battery at $256 is 45 cents a watt hour. High quality generic LiFePO4 batteries are 15 cents a watt hour or less.
I'm new to these small portable battery packs. Would you happen to have any links to the high quality 15 cents per watt hour battery packs? Been seeing so many deals pop up but never sure which ones are high quality and at a good price.
I'm referring to batteries, not battery packs. Look at Eco-Worthy's or DC House's (same company) eBay store.
And you have to buy an extra charger and you have to buy cables and you have to jury rig something up so it will charge when it needs to and so on.
Just because a stand alone battery is cheaper doesn't make it better for everybody's needs.
This just works. You buy it, you lift up the main unit, you put it on top, and you are done. You now have three times the battery capacity in a less than horrible looking form factor. You can even easily detach the extra battery, take it someplace else to charge, and bring it back home in the event of an outage. Or you could charge it off your car's cigarette lighter using any standard charger. Of course, the more power it outputs, the better.
It is easy. Easy often costs more than whatever is cheapest. People's time and aggravation has a value that gets ignored in many of these conversations.
This will run my CPAP machine, my nightstand lamp, and will also charge my smartwatch and my phone, and it will cover all of that for a three day outageThis will run my CPAP machine, my nightstand lamp, and will also charge my smartwatch and my phone, and it will cover all of that for a three day outage. I've tested it.
It will actually run them longer than the larger Delta 3+ because the inverter and other electronics draw less power. If you only need a few hundred peak watts, this is a more efficient device than the larger units. Same applies if you're trying to back up electronics.
And it's a taller, more compact and nightstand friendly shape than the bigger unit.
I am not disagreeing that buying just a battery and your own charger and an inverter and all the separate components works out cheaper. It does.

But good luck taking that pile of wires and boxes camping. And it won't look great piled up next to your bed. Or if you're like us, and you're installing them at a dozens od businesses, you won't get all the convenient remote monitoring without even more hassle. We use them to back up our point of sale systems. They have been working much better for us than our old APC battery backups. And no, we don't have the space for the Delta III Plus under the counters. We needed small and compact.

Money isn't the only consideration. The difference between being cheap and frugal is frugal is about getting a great price on what you want or need. Cheap is just buying cheap because it's cheap.
1
Sep 03, 2025 09:22 PM
2,411 Posts
Joined Dec 2010
coachclassSep 03, 2025 09:22 PM
2,411 Posts
Quote from Zanthexter :
Just because a stand alone battery is cheaper doesn't make it better for everybody's needs.
Sure, this might work better for some. But it's good to just inform (rather than berate) people, which I think is the right tone to take with these complicated product threads.

You can get a plain 1280Wh LiFePO4 battery, more than twice the capacity of this EcoFlow deal, for $160 any day. With the battery, it's pretty easy to plug it into the DC input of the existing 300Wh ecoflow unit to extend the life.

And then you can charge the battery separate from the Ecoflow unit with a cheap charger or any solar setup. The specific Ecoflow extra battery pack seems to need to be charged on the Ecoflow portable unit itself.
Sep 03, 2025 09:57 PM
5,807 Posts
Joined Dec 2004
CaleoSep 03, 2025 09:57 PM
5,807 Posts
Quote from Zanthexter :
Quote from Plutomania [IMG]http://i.slickdeals.net/images/midnight/misc/backlink.gif[/IMG] :
Quote from NE0tekk [IMG]https://slickdeals.net/images/misc/backlink.gif[/IMG] :
Quote from Plutomania [IMG]http://i.slickdeals.net/images/midnight/misc/backlink.gif[/IMG] :
Costco Next products don't carry Costco's guarantee. Each brand has different terms.
EcoFlow's Temu store is run by EcoFlow and shipped direct from EcoFlow, same as Costco Next.
Pricing mistake 7 months ago, or not, the EB600 a 572Wh battery at $256 is 45 cents a watt hour. High quality generic LiFePO4 batteries are 15 cents a watt hour or less.
I'm new to these small portable battery packs. Would you happen to have any links to the high quality 15 cents per watt hour battery packs? Been seeing so many deals pop up but never sure which ones are high quality and at a good price.
I'm referring to batteries, not battery packs. Look at Eco-Worthy's or DC House's (same company) eBay store.
And you have to buy an extra charger and you have to buy cables and you have to jury rig something up so it will charge when it needs to and so on.
Just because a stand alone battery is cheaper doesn't make it better for everybody's needs.
This just works. You buy it, you lift up the main unit, you put it on top, and you are done. You now have three times the battery capacity in a less than horrible looking form factor. You can even easily detach the extra battery, take it someplace else to charge, and bring it back home in the event of an outage. Or you could charge it off your car's cigarette lighter using any standard charger. Of course, the more power it outputs, the better.
It is easy. Easy often costs more than whatever is cheapest. People's time and aggravation has a value that gets ignored in many of these conversations.
This will run my CPAP machine, my nightstand lamp, and will also charge my smartwatch and my phone, and it will cover all of that for a three day outageThis will run my CPAP machine, my nightstand lamp, and will also charge my smartwatch and my phone, and it will cover all of that for a three day outage. I've tested it.
It will actually run them longer than the larger Delta 3+ because the inverter and other electronics draw less power. If you only need a few hundred peak watts, this is a more efficient device than the larger units. Same applies if you're trying to back up electronics.
And it's a taller, more compact and nightstand friendly shape than the bigger unit.
I am not disagreeing that buying just a battery and your own charger and an inverter and all the separate components works out cheaper. It does.

But good luck taking that pile of wires and boxes camping. And it won't look great piled up next to your bed. Or if you're like us, and you're installing them at a dozens od businesses, you won't get all the convenient remote monitoring without even more hassle. We use them to back up our point of sale systems. They have been working much better for us than our old APC battery backups. And no, we don't have the space for the Delta III Plus under the counters. We needed small and compact.

Money isn't the only consideration. The difference between being cheap and frugal is frugal is about getting a great price on what you want or need. Cheap is just buying cheap because it's cheap.
Well said. I'm all for "DIY" when it's appropriate but sometimes no-hassle convenience is what makes sense. Can you get more power output or battery capacity for less money? Sure. But it's not going to be as convenient or easy to use. It also may not be as safe or dependable, depending what you buy and/or how you configure/use it.

Folks here on slickdeals get caught up far too often being insistent on the cheapest possible option, every time. Sometimes that can get you into trouble.
Sep 03, 2025 10:41 PM
4,276 Posts
Joined Nov 2006
ZanthexterSep 03, 2025 10:41 PM
4,276 Posts
Quote from coachclass :
Sure, this might work better for some. But it's good to just inform (rather than berate) people, which I think is the right tone to take with these complicated product threads.
I agree, which is why it gets soooo annoying when people constantly imply folks are stupid for wanting to buy something like the River 3+.

They're usually very dismissive of peoples concerns about size, wife approval, convenience, ease of use, how them want to spend thier time, etc. A lot of people really do NOT want to DIY things. Especially things that can be lethal if mishandled. They want to buy it, unbox it, plug it in, and done.

I happen to be one of them with certain things. I don't want to make maintaining my 3D printer a hobby, I want to make 3D printing a hobby.

I also don't want to make building and maintaining a solar / backup installation my hobby, I just want to not be woken up gasping for air when my CPAP cuts off due to a power outage, and to get a few nights good sleep after a hurricane.

I have things I do want to do with my time, like go visit my son or watch a good movie, or design something fun and new to make with my printer.

Quote from coachclass :
You can get a plain 1280Wh LiFePO4 battery, more than twice the capacity of this EcoFlow deal, for $160 any day. With the battery, it's pretty easy to plug it into the DC input of the existing 300Wh ecoflow unit to extend the life.
Sure, attaching an external battery via the solar inputs is doable. But by the time you buy the charger, the wires, the tools, the fuse, all the rest, you've added significantly to the cost. You've also added a lot of hassle and an ongoing attention sink as you manually manage the external battery.

It will also look like a mess unless you spend even more on a nice enclosure. (No one wants a plastic storage tub next to thier bed.) And of course peoples time has value. I bill $175/hr for mine. It makes more sense for me to work a little overtime than it does for me to futz around with a DIY thing to save money. (I like to futz around with some DIY stuff for the fun of it... But that's a hobby.)

If I was focused solely on price, I wouldn't buy Ecoflow at all.

I also wasn't kidding about the lethality bit. I've got a few dozen of the River 3+ across all of our locations. I can't risk being liable for a janky DIY solution in a cupboard underneath the front counter getting bumped or moved or spilled or piled on top of by a careless employee.

The River 3+ "just works". And we aren't stupid for being willing to pay for that.

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Yesterday 03:12 AM
166 Posts
Joined Mar 2018
PlutomaniaYesterday 03:12 AM
166 Posts
My point was that even on sale it's still expensive. Some may actually be better off buying a Delta 3 Plus than a River 3 Plus and EB600. They'd get more battery for not much more money, size, and weight.
Brands like to engineer problems (proprietary standards) that they "fix" with overpriced accessories. It's like printer cartridges vs ink tanks.
Nothing wrong with making informed buying decisions. And yes, sometimes an overpriced battery in a shiny black plastic case is what the user requires.
1
Today 10:40 AM
4,276 Posts
Joined Nov 2006
ZanthexterToday 10:40 AM
4,276 Posts
Quote from Plutomania :
My point was that even on sale it's still expensive. Some may actually be better off buying a Delta 3 Plus than a River 3 Plus and EB600. They'd get more battery for not much more money, size, and weight.
Brands like to engineer problems (proprietary standards) that they "fix" with overpriced accessories. It's like printer cartridges vs ink tanks.
Nothing wrong with making informed buying decisions. And yes, sometimes an overpriced battery in a shiny black plastic case is what the user requires.
I am all for making well informed decisions...

An informed buyer would know that the Delta 3+ has a shorter run time vs the River 3+ w/ EB600 over multiple days because it has higher idle draw.

An informed buyer would know that the Delta 3+ costs more.

That it takes up more space.

That you can't leave the Delta 3 powering something important while you take 2/3 of it's battery elsewhere to charge and bring back.

And that if you aren't trying to power SDS drills or fridges, the extra peak power of the Delta is irrelevant.

They would also know that if someone makes $25 an hour, and takes 4 hours to research, purchase, assemble, and troubleshoot the DIY thing, when you add that to the cost of the battery, charger, fuse, wires, case, etc. the DIY option costs MORE than this "overpriced battery". The EB600 is the cheaper option when you factor in ALL costs.

For someone that needs less than 600W peak and needs that to last for a few days, and wants it to be compact, the River 3 / Reiver 3 + EB600 is the better choice. That it comes in a nice looking shiny black case, that's just bonus.

Because factoring in ALL the above is what an informed buyer does.

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