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Best $1500 option for 4000 watt hours of battery power? Help......I'm getting very lost in this.

BB has theirs for 899 but you'll lose 5ah. @Just John's link says 999?
No, I said that Costco frequently carries them at two for $1500, but don't currently, and gave a link to the manufacturers website.

 
Really? I'll have 4-100ah BB wired in parallel (4800w)?
(100ah/12) * 4 = 4800

I'll use 4/0 across 8ft to get to the inverter. You're above suggests that's not possible, or at least, shouldn't be done?
Are you planning on using all 4800 watts in an hour? That's a heck of a load at 12 volts.
If not, the calculate based on what your PEAK usage is.
A typical US house outlet is wired/fused for 15 amps at 120v (or about 1800 watts per hour).
 
I'm getting a bit confused here. My load that I'm aiming to supply is approx. 400 watts for up to 8 hours.

Also, I thought I got a great deal on these 2x 200AH LithPO4 for $1528. delivered? Is it proper to show a link? I got to this link from Will's site.

I guess what I'm asking is if there are better options out there for that money today, I could cancel this order??
 
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I'm getting a bit confused here. My load that I'm aiming to supply is approx. 400 watts for up to 8 hours.

Also, I thought I got a great deal on these 2x 200AH LithPO4 for $1528. delivered? Is it proper to show a link? I got to this link from Will's site.

I guess what I'm asking is if there are better options out there for that money today, I could cancel this order??
ready to go.. that sounds like a good deal
 
I'm getting a bit confused here. My load that I'm aiming to supply is approx. 400 watts for up to 8 hours.

Also, I thought I got a great deal on these 2x 200AH LithPO4 for $1528. delivered? Is it proper to show a link? I got to this link from Will's site.

I guess what I'm asking is if there are better options out there for that money today, I could cancel this order??
So, under 40 amps continuous. Unless you have some massive surge, 0 gauge (not 0000 gauge) would suffice without breaking a sweat, over a distance of 8 feet (16 feet, since both positive and negative count). The 0 gauge would pretty much work for handling all 200 amps they would be capable of. The 100 amp BMS (especially two in parallel) should be able to handle that (or about a 2000 watt inverter).

 
Arriving Jun 9 - Jun 14


2
12V 200Ah Lithium Iron LiFePO4 Deep Cycle Battery, Built-in 100A BMS, 2000+ Cycles, 280amp Max, Perfect for RV, Solar, Marine, Overland, Off-Grid Application;
Sold by: Ampere Time US
There was an additional coupon for $39.20 bringing the total to 1528.78. This seems to be WAY less than I've seen for 400AH of LiFePO4. Am I missing something guys??
$783.99
Business Price
Condition: New
Buy it again

That is a good price, don't worry.
You could build bigger batteries yourself cheaper, but for a pre-built battery that is a good price.
I have no knowledge of their quality, but if you believe Amazon reviews, it's good.
 
Really? I'll have 4-100ah BB wired in parallel (4800w)?
(100ah/12) * 4 = 4800

I'll use 4/0 across 8ft to get to the inverter. You're above suggests that's not possible, or at least, shouldn't be done?
I personally would never you only 12v for that wattage but the calculation was just as an example.
In your case I would most likely wire it 2S2P for 24v 200 amps.
Now just because you have 200amps it does not mean you can't use a 100 amp fuse or breaker and wire combo.
It all goes back to what do you need.
The wire gauges I noted where from this chart.
 
So, under 40 amps continuous. Unless you have some massive surge, 0 gauge (not 0000 gauge) would suffice without breaking a sweat, over a distance of 8 feet (16 feet, since both positive and negative count). The 0 gauge would pretty much work for handling all 200 amps they would be capable of. The 100 amp BMS (especially two in parallel) should be able to handle that (or about a 2000 watt inverter).

I was thinking of something like this for a all in one, would this be a good size for me?

MPP Solar LV2424​

 
I was thinking of something like this for a all in one, would this be a good size for me?

MPP Solar LV2424​

I'm trying to figure out why you want a 2400 watt inverter to run a 400 watt load.
You were asking about cable sizes to run a 400 watt load, and now ask if a 2400 watt inverter is a good size for you?

I have no idea. For 2400 watts at 24v, you will need to supply about 125 amps (inverter efficiency). 2400 ÷ 24 = 100 amps. This is very different than 400 watts. Can those batteries handle being run in series? A lot can't.
 
I'm trying to figure out why you want a 2400 watt inverter to run a 400 watt load.
You were asking about cable sizes to run a 400 watt load, and now ask if a 2400 watt inverter is a good size for you?

I have no idea. For 2400 watts at 24v, you will need to supply about 125 amps (inverter efficiency). 2400 ÷ 24 = 100 amps. This is very different than 400 watts. Can those batteries handle being run in series? A lot can't.
Hi John, I had read Will's article saying you should buy a larger inverter than you need. I just bought 2x200 AH LiFePO4 ampere time batteries. Right for now, I'll have no solar panels but hope to in a year and just want to get it right the first time.

Yes, the batteries can be run in series.

Now, I'm thinking of just getting a 24V charger/inverter but not sure what I need to get this started properly. It's been too confusing to look at all of the options and I need it to simply be a overnight backup for now, that I can recharge the next day either by the grid or my Honda I2200 generator.

I have too much other stuff happening to learn it all right now today, so I want to solve my immediate needs for now and grow later on, (adding solar panels and disconnects. I'll be happy right now to run extension cords to my refrigerators and fans. Then next year add solar.

I also thought I should get an inverter that would allow both refrigerators the starting current they need if both came on at once (1500 Watts) while I had other loads going.

I thought Inverters could handle "surge watts" but I don't know what size to get and be able to handle the surge?

I had started out buying a 12 volt 1000 watts, 2,000 surge inverter but returned it after learning I was way better off with 24 volts. I would like to keep the costs down and don't want more than I need.
 
Since you already bought 2 units of 12V-200Ah batteries, and your constant load is 400W, purchasing a 2400W cont. inverter (12V), it will work for your 400W refrig. In the future, if you want to upgrade, then you can do it. Make sure, you have proper wire from batteries to an inverter, correct fuse between batteries and an inverter (at the positive side). Note: just be mindful, that each battery is limit to 100Ah.
 
Since you already bought 2 units of 12V-200Ah batteries, and your constant load is 400W, purchasing a 2400W cont. inverter (12V), it will work for your 400W refrig. In the future, if you want to upgrade, then you can do it. Make sure, you have proper wire from batteries to an inverter, correct fuse between batteries and an inverter (at the positive side). Note: just be mindful, that each battery is limit to 100Ah.
Thanks. I've already decided to go 24 volts and when both refrigerators start it's 1400+ watts
 
Thanks. I've already decided to go 24 volts and when both refrigerators start it's 1400+ watts
Yes, looked up the specs on the MPP model you asked about. It is capable of 60 amp charge to 24v batteries. So about 15 amps A/C (very common single household circuit size, and depending on efficiency). Likely, as long as your Honda can put out that amount for hours on end, it will work for you. I would go ahead and wire, fuse, or circuit breaker it for 200 amps, in case you decide to get a second set of batteries. Assuming you get a 100% efficient inverter (no such thing) you can run 2400 watts off a 24v battery rated at 100 amps (what you purchased). Keep your usage under 2000 watts, otherwise you might be killing the BMS built into the batteries.
 
I personally would never you only 12v for that wattage but the calculation was just as an example.
In your case I would most likely wire it 2S2P for 24v 200 amps.
Now just because you have 200amps it does not mean you can't use a 100 amp fuse or breaker and wire combo.
It all goes back to what do you need.
The wire gauges I noted where from this chart.
I can't rig it for 24v - the inverter will only accept 12vdc.

I used this chart that seems to imply I'm ok?
 
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