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diy solar

Future of DIY LiFePO4 looks bleak…

This thread is about to celebrate it's 3 year birthday!
My brother after Thanksgiving dinner was blabbing about one of Will's videos where Will stated it was cheaper to purchase premade batteries than DIY.

My brother is now an expert because he watched a few of Will's videos.

My response, "My batteries are 280Ah, cells run $74 each plus shipping which varies according to the quantity and whether you want the $330 Luyuan box with it that includes shipping. JK BMS with screen is about $125. About $1800 for 280Ah while a 100Ah premade server rack battery with metal case is about $1300 average. Which is the better deal? And yes, I belong to his online forum".
 
For me, 115kWh ESS in factory packs (using your figures)
1300 $1100 x 23 packs = $29,900 $25,300 USD Edit per @Brucey below.
or
1800 x 8 pack = $14,400 USD
Which is the better deal?!
 
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My brother after Thanksgiving dinner was blabbing about one of Will's videos where Will stated it was cheaper to purchase premade batteries than DIY.

My brother is now an expert because he watched a few of Will's videos.

My response, "My batteries are 280Ah, cells run $74 each plus shipping which varies according to the quantity and whether you want the $330 Luyuan box with it that includes shipping. JK BMS with screen is about $125. About $1800 for 280Ah while a 100Ah premade server rack battery with metal case is about $1300 average. Which is the better deal? And yes, I belong to his online forum".
And the individual cells are even cheaper now, especially if going with an 'off brand' name, or sourcing from China. IIRC, many of the premade batteries use 'off brand' cells.

I don't always agree with 'the experts'.
 
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My brother after Thanksgiving dinner was blabbing about one of Will's videos where Will stated it was cheaper to purchase premade batteries than DIY.

My brother is now an expert because he watched a few of Will's videos.

My response, "My batteries are 280Ah, cells run $74 each plus shipping which varies according to the quantity and whether you want the $330 Luyuan box with it that includes shipping. JK BMS with screen is about $125. About $1800 for 280Ah while a 100Ah premade server rack battery with metal case is about $1300 average. Which is the better deal? And yes, I belong to his online forum".
It's not 1300 anymore. They're as low as 720. And if you go with 50ah, 450 for 2. Battery wars are bringing prices down
 
I like the control and experience of the DIY packs.
We may see solar inverters move away from 48v one day, and all the DIY packs can be opened and rearranged for the new voltage if that comes to pass.
If one cell in a pack shows signs of weakness in 8 years - I have spares to swap in.
Projects like ICE-to-Electric lawn tractor would be a snap.
Need a 72volt pack for a special project - not a problem,
If I want to expand my 24v system by re-building a 48v pack into two 24v - can be done in no-time.
too much fun.
I keep playing with the idea of a 100kWh mega-pack that can slide into a pick up box, or between the C-channel rails of a trailer - for added EV range...love seeing the cell prices continue to drop.
 
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My brother after Thanksgiving dinner was blabbing about one of Will's videos where Will stated it was cheaper to purchase premade batteries than DIY.

My brother is now an expert because he watched a few of Will's videos.

My response, "My batteries are 280Ah, cells run $74 each plus shipping which varies according to the quantity and whether you want the $330 Luyuan box with it that includes shipping. JK BMS with screen is about $125. About $1800 for 280Ah while a 100Ah premade server rack battery with metal case is about $1300 average. Which is the better deal? And yes, I belong to his online forum".
If he was talking about say running four ecoworthy 280ah 12v in series, at $400 each with 20% off coupon you are at $1800+$60 for a balancer. Agreed when compared to an off the shelf 14-16kWh battery at $3200+ there can be significant savings to diy.

I would say the general pricr bar for a 5 kWh rack mount is now at $1100 with the midnite solar unit.
 
High voltage just seems way too logical to not go that way...
just like 12v to 24v to 48v - generally to keep the amperage below 200-400
but then we see larger and larger inverters - 10kW and 12kW inverters look 'common place' now.
Moving towards a full 200A 240 service? - 48kW inverter or two 24kW paired up...
but wire them with what wire? 750MCM cables? Higher voltages would cut these down to normal wire sizes again.

Remember not long ago, PV line voltages were 140-250vDC and jumped up to 500v and more, reducing current and wire sizes.
and EV batteries have gone up to 800v on some models.
 
High voltage just seems way too logical to not go that way...
just like 12v to 24v to 48v - generally to keep the amperage below 200-400
but then we see larger and larger inverters - 10kW and 12kW inverters look 'common place' now.
Moving towards a full 200A 240 service? - 48kW inverter or two 24kW paired up...
but wire them with what wire? 750MCM cables? Higher voltages would cut these down to normal wire sizes again.

Remember not long ago, PV line voltages were 140-250vDC and jumped up to 500v and more, reducing current and wire sizes.
and EV batteries have gone up to 800v on some models.
Sure seems logical.
 
Control. Reason I went the DIY route. As recently stated it gives me designer flexibility. I can mix and match and restructure my cells in multiple configurations. I am in that current situation. I have a misbehaving cell in one of my batteries. If the cells were welded as in most prebuilt. I would have a very heavy paperweight with a bunch of wasted cells because the one runner (or lagger) limited the capacity. I will be pulling the cell and mixing and matching into two 12v lower demand batteries and replacing with a batch I just received from Amy (top notch product by the way!).

Yes, there is the convenience factor with prebuilt and it is a dopamine rush looking at all the "shiny" bits and pieces. Until the next model comes along to make it obsolete. With DIY I have total control over the cell configuration, voltage, BMS, case, display and more. With prebuilt if something goes wrong, I can get in line with the others who are still trying to get their unit serviced, IF they can afford or work out the freight shipping to move it back and forth.
 
It's not 1300 anymore. They're as low as 720. And if you go with 50ah, 450 for 2. Battery wars are bringing prices down
Links? Can't be much quality there for $720 on a 48V 100Ah.

Anyway, 280 Ah pack at $1800 is $6.43/Ah while 100 Ah for $720 is $7.20/Ah.

That is 10.69% cheaper. It can be even cheaper if you don't use the Luyuan box. $1800 - $330= $1470

That is $5.35/Ah which is 25.69% cheaper.

When you start building 114 Kwh banks, that 10.69% to $25.69% adds up. Take the bank I'm currently building, the box was $200, paint and material will put it at around $800 total. The JK's with screens 125 x 8= $1,000. Class T's were $60 x 8= $480. Luyaun EVE new cells at $74 (shipping not included) x 128 = $9,472. Cables and busbars another $300. Total = $12,062

Meanwhile the 100Ah server rack battery cheapie for $720 (need a link for that), will take 23 batteries (shipping not included) x $720 = $16,560. I would have no control over the quality. Take this AO Lithum thread. You can have it, I wouldn't put that in my house or shop. I still beat it with the 114 Kwh bank by 27%.

In reality, the $1300 is average price for something comparable to what I build and 23 x $1300= $29,900 My box is 59.65% less.

If your income increased by 27%, would you accept it? How about 59.65%?
 
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High voltage just seems way too logical to not go that way...
just like 12v to 24v to 48v - generally to keep the amperage below 200-400
but then we see larger and larger inverters - 10kW and 12kW inverters look 'common place' now.
Moving towards a full 200A 240 service? - 48kW inverter or two 24kW paired up...
but wire them with what wire? 750MCM cables? Higher voltages would cut these down to normal wire sizes again.

Remember not long ago, PV line voltages were 140-250vDC and jumped up to 500v and more, reducing current and wire sizes.
and EV batteries have gone up to 800v on some models.
What do you need it for on the average home? If your house is sucking that much power, then one needs to start looking at conservation before spending a dime on a PV system. Plus, with AC coupling, no need for HV DC batteries or large cables. That would be the direction things would take if very large loads need to be powered.

Tesla was a smart man, he knew AC was better than DC.
 
If he was talking about say running four ecoworthy 280ah 12v in series, at $400 each with 20% off coupon you are at $1800+$60 for a balancer. Agreed when compared to an off the shelf 14-16kWh battery at $3200+ there can be significant savings to diy.

I would say the general pricr bar for a 5 kWh rack mount is now at $1100 with the midnite solar unit.
Go look at my figures and I'm not building a system for house or shop with Eco Worthy batteries in series. Let's face reality at what works and what doesn't.
 
Go look at my figures and I'm not building a system for house or shop with Eco Worthy batteries in series. Let's face reality at what works and what doesn't.
I understand the general advice is to avoid series batteries and sticking with "nominal voltage" to avoid issues. Personally I went the other way starting with four 12v 100ah, then a few of some 24V 100ah in series, then finally a 48v 100Ah rack mount as my first "big boy" battery. While it's nice to be able to see cell voltage etc functionally it's not any different from my random array of batteries. I call it MAIB (multiple array of independent batteries). Even with failure of one or more strings the battery bank continues functioning, my goal at the time being to keep pricing at around $800 or less per 5kWh, and allow for moving by one person.

Now I'm at the diy for 280Ah stage, but will still keep the other 24V and 12V in the system.
 

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