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Can 280/300ah cells reliably drive 2000w pure sine inverter

sunrise

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Hi all,
I am wondering if these 280/300/310ah cells can reliably power a 2000w inverter continuously (> 10 minutes) in a 12v setup? Let's assume BMS can handle this.
I plan to build a 4s 12v system in an RV with a Renogy 2000w pure sine wave inverter, and run some high wattage appliances like coffee maker, toaster, hair dryer with it. So the battery needs to be able to handle ~180-200A discharge for more than 5 minutes.
I don't need to charge them at this rate, they will be charged at < 50A.
This is still well below 1C (280a) but greater than 0.5C

Thanks in advance!
 
Hi all,
I am wondering if these 280/300/310ah cells can reliably power a 2000w inverter continuously (> 10 minutes) in a 12v setup?
You mean these cells?
 
You mean these cells?
yeah, these 280ah cells popular on this forum. I don't know which brand/seller has ones that can handle 200a discharge though. I remember a few days back I read some brand are only good for 0.5c continuous discharge. That won't work in my application.
 
it is easiest if you just convert all your loads and sources into watts and/or watt hours so you do not get confused by the battery bank voltage.

with a 300Ah battery cell a 4S (12V system) means you have 4* 3.4v * 300Ah which is around 4080 watt hours.

ignoring ALL cable and inverter losses and assuming the BMS can handle whatever current draw is needed you get:

a 2000w inverter would draw a current of 2000 / (3.4v * 4) = 147Amps (thats a lot hehe) to support a 2000W load.

since you have a 4080 watt hour battery you can run a 2000watt load for:

4080w / 2000 = 2hours

in reality you do not run the batteries until they are dead and the inverter/wiring will use power as part of the conversions.
 
yeah, these 280ah cells popular on this forum. I don't know which brand/seller has ones that can handle 200a discharge though. I remember a few days back I read some brand are only good for 0.5c continuous discharge. That won't work in my application.
The devil is in the details.
Have a look at the spec sheet I linked, look for max continuous discharge.
Whatever battery you buy, be sure to look at the data sheet.
 
You mean these cells?

The devil is in the details.
Have a look at the spec sheet I linked, look for max continuous discharge.
Whatever battery you buy, be sure to look at the data sheet.
Thanks! If they really perform as stated in datasheet, then it's all good.
 
Thanks! If they really perform as stated in datasheet, then it's all good.
2000 ac watts / .85 conversion factor / 1.12 ripple factor / 10 volts low cutoff = 263.529411765 service amps.
263.529411765 service amps / .8 fuse headroom = 329.411764706 fault amps
@Hedges ^

Which is below 1c(280 amps)
 
it is easiest if you just convert all your loads and sources into watts and/or watt hours so you do not get confused by the battery bank voltage.

with a 300Ah battery cell a 4S (12V system) means you have 4* 3.4v * 300Ah which is around 4080 watt hours.

ignoring ALL cable and inverter losses and assuming the BMS can handle whatever current draw is needed you get:

a 2000w inverter would draw a current of 2000 / (3.4v * 4) = 147Amps (thats a lot hehe) to support a 2000W load.

since you have a 4080 watt hour battery you can run a 2000watt load for:

4080w / 2000 = 2hours

in reality you do not run the batteries until they are dead and the inverter/wiring will use power as part of the conversions.
Thank you, I know how to calculate the ah numbers. My question is how reliable these 280ah cells are @ 0.5-1C continuously.
 
Thank you, I know how to calculate the ah numbers. My question is how reliable these 280ah cells are @ 0.5-1C continuously.
That depends on a lot of really murky factors.
If you get the real deal from the manufacturer probably no problem.
If you get them from some broker who intercepted cells destined for landfill probably not going to work.
 
Last edited:
There are some good brokers that have a proven track record on this forum.
 
Last edited:
Thank you, I know how to calculate the ah numbers. My question is how reliable these 280ah cells are @ 0.5-1C continuously.
wow... you are really asking for a reading of the tea leaves then ;)

if you want "guaranteed" performance then you almost certainly need to purchase a pre-validated system...and price would be painful.
You can also buy X(what you need)+N(extra that you can test and swap with) cells and you yourself can build a matched system that you know will meet your needs.

It is often much cheaper to "over spec" (4S2P) so you are not trying to hit some space/volume requirements...unless you are trying to fit this is a small volume(boat, space vehicle) where performance is key driver.

even good suppliers sometimes get a bad battery...even good companies sometimes PRODUCE bad batteries!

if you want reliability then either you, or "someone", has to test each component to meet your specific needs.
 
wow... you are really asking for a reading of the tea leaves then ;)

if you want "guaranteed" performance then you almost certainly need to purchase a pre-validated system...and price would be painful.
You can also buy X(what you need)+N(extra that you can test and swap with) cells and you yourself can build a matched system that you know will meet your needs.

It is often much cheaper to "over spec" (4S2P) so you are not trying to hit some space/volume requirements...unless you are trying to fit this is a small volume(boat, space vehicle) where performance is key driver.

even good suppliers sometimes get a bad battery...even good companies sometimes PRODUCE bad batteries!

if you want reliability then either you, or "someone", has to test each component to meet your specific needs.
Thanks, due to space constraint I can't have these cells in 4s2p configuration, My current setup is actually 4s2p of 105ah cells, with 2 120A JBD BMSes. the inverter I have is a 1000W one so they do fine. in theory they should be able to pump out 210A per data sheet, but the tiny terminal screws (M4?) and busbars make me not wanting to try that
 
Get welded studs, and buy bus bars with proper 6mm holes. Clean and prep the connections very carefully, use no-alux or something to avoid corrosion. Torque to spec.

Over 100a the connections and terminations start to matter a lot, and these aluminum terminals are SOFT.

Double the cells to reduce the power. Either 24v or 2x12v.

Good luck and let us know how it goes.
 
OP:
Is your inverter really rated at 2000W continuous output and at what temperature?
 
OP:
Is your inverter really rated at 2000W continuous output and at what temperature?
I "think" he is in the planning stages and wants to know if a 300Ah 4S battery pack could supply a 2000W load for at least 5-10minutes...

so the answer is YES, ...if... your battery pack can handle a constant load of at least 150amps (so thats 0.5c for a 300Ah pack), and your bms+inverter can handle that continuosly as well.
Due to your space constants you will need to watch your heat; bigger wires and oversizing the bms would be a good idea.

I am not sure where 200Amps came from in first post as 200Amps * 13v = over 2000 watts unless you are thinking the conversion losses.
All the loads you mentioned are mostly resistive so no reactive surges to worry about.

so just make sure you get constant discharge 1C batteries...
 
I suggest you should have a compression rig.
Also Stress test the cells and you an ir temperature sensor to monitor the cells.
I've noticed that the cell temperature increase with high dishcarge rates.
Particularly in the low knee.
 
There are some good brokers that have a proven track record on this list.

Get welded studs, and buy bus bars with proper 6mm holes. Clean and prep the connections very carefully, use no-alux or something to avoid corrosion. Torque to spec.

Over 100a the connections and terminations start to matter a lot, and these aluminum terminals are SOFT.

Double the cells to reduce the power. Either 24v or 2x12v.

Good luck and let us know how it goes.
Thanks! agree that the connections and terminations matter a lot over 100a. That's one of the main reason I want to build a new battery bank.
 
I "think" he is in the planning stages and wants to know if a 300Ah 4S battery pack could supply a 2000W load for at least 5-10minutes...

so the answer is YES, ...if... your battery pack can handle a constant load of at least 150amps (so thats 0.5c for a 300Ah pack), and your bms+inverter can handle that continuosly as well.
Due to your space constants you will need to watch your heat; bigger wires and oversizing the bms would be a good idea.

I am not sure where 200Amps came from in first post as 200Amps * 13v = over 2000 watts unless you are thinking the conversion losses.
All the loads you mentioned are mostly resistive so no reactive surges to worry about.

so just make sure you get constant discharge 1C batteries...
Thanks! I will likely use one of the brokers on this forum to get the cells, not sure if they supply BMS as well. I have purchased many things from aliexpress and I have to say I'd rather pay a little more to have a good mood :D
 
Hi all,
I am wondering if these 280/300/310ah cells can reliably power a 2000w inverter continuously (> 10 minutes) in a 12v setup? Let's assume BMS can handle this.
I plan to build a 4s 12v system in an RV with a Renogy 2000w pure sine wave inverter, and run some high wattage appliances like coffee maker, toaster, hair dryer with it. So the battery needs to be able to handle ~180-200A discharge for more than 5 minutes.
I don't need to charge them at this rate, they will be charged at < 50A.
This is still well below 1C (280a) but greater than 0.5C

Thanks in advance!
I have the eve 280AH cells and they can handle the discharge necessary to run a 2000 watt inverter. Due to losses and voltage sag, expect amperage to be in the 170-190 amp range for 2000 watts, not 2000 divided by 12. The bigger issue is whether a cheap Renogy inverter can handle 2000 watt continous. I have friends with Renogy stuff and my educated guess is no. There is a reason their inverters are so much cheaper than reputable brands like Victron, Xantrex etc.
 
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