frontpage Posted by MinhTrinh • Last Thursday
Apr 10, 2025 5:04 AM
Item 1 of 3
Item 1 of 3
frontpage Posted by MinhTrinh • Last Thursday
Apr 10, 2025 5:04 AM
EF ECOFLOW DELTA 2 Max Power Station Extra Battery
+ Free Shipping$759
$1,399
45% offAmazon
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edit.. just saw EF are selling their refurbs on ebay for the same price. this post is brand new. Gonna pull the trigger.
Our community has rated this post as helpful. If you agree, why not thank killercut
The wire it comes with has an o ring terminal. You just put the o ring on the bolt for the lifepo4 batrery. if you want to put more batteries in parallel you just get a wire with o ring terminals on them and add as many as you want. but you shouldnt need more than 2 or 3. 1 12v 100ah will even suffice for most people. if paralleling additional batteries, make sure they are either full before connecting them together or the voltage is nearly the same. not more than like .2v difference. the batteries will then equalize to the same voltage. if you do series, it gets more complicated and you need to disconnect them every 3-6 months to balance them seperately and only connect them when full and balanced, so paralleling is better since its easier and less problems. 12v 100ah are about 22lbs, so its nice having lighter batteries for when you want to move them around once you get to 12v 200ah or 24v100ah they are double that and a pain to move around.
I thought it was a whole unit as well.
with batteries wired in series at a higher voltage, such as 36v or 48v, you can feed the delta 2 max at (500w+500w), or 1000 watts.
https://www.amazon.com/dp/B08843STJ1?th=1
...and wired the o-ring terminals that come on the end of the alternator charger cables to these clamps (there's a nut provided where you can screw the wire down to the clamps), so i don't have to fiddle around with unscrewing and re-screwing the alternator charger to the battery terminals of each battery.
i can quickly just use the battery clamps to hook up the alternator charger to an external battery, and then, if need be, i can quickly remove the clamps and clamp it on to another spare battery.
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with batteries wired in series at a higher voltage, such as 36v or 48v, you can feed the delta 2 max at (500w+500w), or 1000 watts.
The alternator itself does 800w both ways. Why would you even need to run at over 800w constant? The delta 2 max by itself would only run for 2 hours at like 800w... using the alternator for backup power during a blackout, you would likely draw around 200w-300w, to power a fridge and maybe some led lights and charge a phone and maybe wifi/internet... then recharge via generator during the day at 800w.
the alternator charger does not plug into the solar port. it plugs into the expansion battery port. so, i was talking about for those who do not have an alternator charger, which costs $200-$300, and just want to use an inexpensive o-ring to xt60i cable for around $10-$15 plugged into the pv port.
at 12v they will only be able to feed the solar input ~200 watts using one of those cables. not everyone wants to spend a few hundred on an alternator charger. some might want to use a 15 dollar cable to feed the power station up to 500 watts from an external battery (at higher voltages).
obviously if you have an alternator charger, you can feed the power station up to 800 watts from a 12v or 24v battery or reverse charge and charge the external battery using the power station.
i was using my alternator charger today, so i am familiar with how it functions.
the alternator charger does not plug into the solar port. it plugs into the expansion battery port. so, i was talking about for those who do not have an alternator charger, which costs $200-$300, and just want to use an inexpensive o-ring to xt60i cable for around $10-$15 plugged into the pv port.
at 12v they will only be able to feed the solar input ~200 watts using one of those cables. not everyone wants to spend a few hundred on an alternator charger. some might want to use a 15 dollar cable to feed the power station up to 500 watts from an external battery (at higher voltages).
obviously if you have an alternator charger, you can feed the power station up to 800 watts from a 12v or 24v battery or reverse charge and charge the external battery using the power station.
i was using my alternator charger today, so i am familiar with how it functions.
Yea, but even with using the solar ports, how are they going to charge their lifepo4 batteries. At $220 for the alternator charger they get a 60amp charger. An equivalent car charger or lifepo4 charger would be $220+ anyways. With the ecoflow alternator it does both ways, so win win.
since you mentioned plugging a cheap 12v battery into the solar port, and also mentioned using a car or lifepo4 charger to charge it back up, i was referring to those who want to use this cheaper methodology, who don't have an alternator charger.
some people may have an existing 12v lead-acid battery charger, and it doesn't even have to be a lifepo4 one. you can charge a lifepo4 with a regular battery charger, although it's better to use one specifically suited for lifepo4 if you can.
i was simply pointing out that you can use a cheap 10 or 15 dollar cable to feed your delta 2 max from a cheap 12v lifepo4 battery, but at 12v, it will only be around 180 watts or so. at 24 you can do more like 360 watts, and with a 48v battery or four 12v in series at 48v, you can feed the delta 2 max the full 500 watts from an external battery.
see here for a real-world example on the delta 2 max:
https://youtu.be/tK4JKmfndh8?t=3
of course, i think the alternator charger is a slick and useful device, which is why i got one. and with this device, you can send 800w into the power station, or back out from the power station to charge an external 12v or 24v battery (won't work with 36v or 48v).
home depot is selling the delta pro ultra 6.144 kwh batteries for $1599. (even less if you use a home depot coupon, like $15 off $100, or $75 off $500, etc.) that battery has three times the capacity as this one (6kwh vs. 2kwh), but three of these at $759 totals $2277, vs. $1599 for the same capacity of the delta pro ultra battery. of course, i realize that the delta pro ultra battery does not work with the delta 2 max, but the battery is still overpriced for the capacity you get.
which is why killercut was suggesting you can buy non-ecoflow batteries to expand the capacity of your delta 2 max. for $759, you can almost buy a 48 volt server rack battery, which is 5.12 kwh, vs. this one, which is only a measly 2 kwh.
so, you are paying nearly 2 1/2 times the price per watt, compared to a budget brand server rack battery, just to add a couple kwh of battery storage.
i get that it is nice to have the matching ecoflow branded expansion battery, and it seamlessly integrates and communicates with the ecoflow power stations, but imo, it's still not worth it for this price.
if it were me (i realize everyone is different and may not agree), but i would rather take the $759 and buy a bluetti elite 200 v2, which i think is an overall better power station than the delta 2 max. you still get your 2 kwh of battery capacity, but you also get an extremely efficient (and quiet) 2600-2800+ watt inverter, in a nice compact form factor, that can allow you to take in up to 1000w more solar.
i just don't think this deal is all that great. a good deal on this battery would be more like 500 or 600 tops.
home depot is selling the delta pro ultra 6.144 kwh batteries for $1599. (even less if you use a home depot coupon, like $15 off $100, or $75 off $500, etc.) that battery has three times the capacity as this one (6kwh vs. 2kwh), but three of these at $759 totals $2277, vs. $1599 for the same capacity of the delta pro ultra battery. of course, i realize that the delta pro ultra battery does not work with the delta 2 max, but the battery is still overpriced for the capacity you get.
which is why killercut was suggesting you can buy non-ecoflow batteries to expand the capacity of your delta 2 max. for $759, you can almost buy a 48 volt server rack battery, which is 5.12 kwh, vs. this one, which is only a measly 2 kwh.
so, you are paying nearly 2 1/2 times the price per watt, compared to a budget brand server rack battery, just to add a couple kwh of battery storage.
i get that it is nice to have the matching ecoflow branded expansion battery, and it seamlessly integrates and communicates with the ecoflow power stations, but imo, it's still not worth it for this price.
if it were me (i realize everyone is different and may not agree), but i would rather take the $759 and buy a bluetti elite 200 v2, which i think is an overall better power station than the delta 2 max. you still get your 2 kwh of battery capacity, but you also get an extremely efficient (and quiet) 2600-2800+ watt inverter, in a nice compact form factor, that can allow you to take in up to 1000w more solar.
i just don't think this deal is all that great. a good deal on this battery would be more like 500 or 600 tops.
Forget the bluetti, go for the delta 3 pro if you need more power. Refurbished for $2000 on ebay or get the 2 pack from costco and return rebuy when the price drops again. It has 240v which makes it a lot more useful. Also has higher voltage solar input so you can connect some serious solar arrays.
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yeah, the delta pro 3 does 2600w solar input, while the bluetti maxes out at 1000w, but when it's one third of the price, three of the bluettis can take in just as much solar.
the delta pro 3 was $2000 new (nor refurb), not long ago, and if someone requires 240v, at that price or lower, i think it's a good choice. i would like one.
i like the ecoflow styling/design better than the bluetti, and i think ecoflow has a nicer app, but based on raw performance, the bluetti has a more robust inverter, is more efficient with less idle consumption, in a noticeably smaller form factor than the delta 2 max.
the elite 200 v2 was released more recently (november 2024), so that's why it has surpassed the delta 2 max in performance. i'm sure when ecoflow eventually releases the delta 3 max, i will probably want it more than the bluetti.