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upgrading from FLA to LiFePO4. Suggestions for: Best communication, Bttry mgmt sys, best lifetime, best storage and least maintenace?

Sun_Dried_Toad

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Sep 6, 2020
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48v system.

Sol-Ark 12k all-in-one

8,650w PV

totally off-grid home.



we are building a new home. will be off-grid. when we move, we will expand/upgrade our current system. current system is 2440w and supports about 40% of our home off-grid.

currently, we use 300AH of FLA Trojan T-1275. they work quite well, but I do not want to have to check and maintain FLA at the new home.

as of right now, I am leaning towards Fortress eFlex. that said, we all know they are crazy expensive, but I like the built in BMS and communication with the sol-ark unit. stand alone wifi communication to my phone is a bonus as well.

can i do as good or better with another plug and play option? would it be better to build DIY?
 
I use three eFlex batteries with my Sol-Ark 12K and they are really good. I also have an EG4LL and it's a night and day difference. The eFlex is a Tier one battery and the fully certified for Grid tied installations. The BMS inside is an industrial BMS used in the Aviation market with a built in Class T Fuse. The thing that sets them apart is that they don't use MosFets for the internal battery connection but instead use a industrial Relay. The Relay gives them a much lower ESR so basically they charge about 40% faster than the lower priced batteries like the EG4LL and they can also discharge much more power if needed. On a sunny day my 10Kwp of panels will charge the 3 eFlexes fully by 11am. The EG4 will still be at 70% and take until 12:30pm to fully charge. Fortress powers customer service is the best CS that I have come across, it is actually better than Sol-Arks. They will literally spend hours with you on the phone helping you with the setup.
The construction of the battery is like a Tank, it has a 4mm thick aluminum case and is air tight.
The both companies work very closely together so closed loop battery communication between the Inverter and the battery is excellent and very easy to setup.

I also like the eVault Max but my electrical room is not in the garage and that 500lb beast was just going to be to hard to get into the electrical room without some serious amount of man power.
 
I use three eFlex batteries with my Sol-Ark 12K and they are really good. I also have an EG4LL and it's a night and day difference. The eFlex is a Tier one battery and the fully certified for Grid tied installations. The BMS inside is an industrial BMS used in the Aviation market with a built in Class T Fuse. The thing that sets them apart is that they don't use MosFets for the internal battery connection but instead use a industrial Relay. The Relay gives them a much lower ESR so basically they charge about 40% faster than the lower priced batteries like the EG4LL and they can also discharge much more power if needed. On a sunny day my 10Kwp of panels will charge the 3 eFlexes fully by 11am. The EG4 will still be at 70% and take until 12:30pm to fully charge. Fortress powers customer service is the best CS that I have come across, it is actually better than Sol-Arks. They will literally spend hours with you on the phone helping you with the setup.
The construction of the battery is like a Tank, it has a 4mm thick aluminum case and is air tight.
The both companies work very closely together so closed loop battery communication between the Inverter and the battery is excellent and very easy to setup.

I also like the eVault Max but my electrical room is not in the garage and that 500lb beast was just going to be to hard to get into the electrical room without some serious amount of man power.
Dang Dude.

I hear ya but You are talking about $700 a KWH?.
$13000/18kwh.
Man this batteries better cook breakfast for that kind of price.

Can we not just buy the same BMS and make our own?

There is also these batteries made up in Amish county.

I know Gains Solar and Engineer 775 have used them and when I priced them they were not as cheap as The EGL but seemed at least comparable.

 
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Yep they are not cheap, but if you look at all the Tier one batteries on the market they are actually in the same price range if not cheaper.
EcoDirect LFP Batteries
But if they last twice as long as my EG4LL then it really did not cost me any more money.
 
Yep they are not cheap, but if you look at all the Tier one batteries on the market they are actually in the same price range if not cheaper.
EcoDirect LFP Batteries
But if they last twice as long as my EG4LL then it really did not cost me any more money.
I hear ya but that just hurts my soul to pay that much for some cells, case and BMS.

I could just about replace my whole battery bank for 2 of those 18.5 KWH batteries.

I won’t live but maybe 20 more years at most so I guess I’m looking at it from that standpoint.
 
At the time when I purchased them the choice was either Tier 1 or DIY a bank of batteries from Alibaba.
There was no low cost server rack packs back then and the Wife factor was really a huge consideration.
I really wanted something that would be very reliable and user friendly. The Wife was very skeptical of solar. I had to guarantee her that this was not going to be some hobby project that might break down and leave her stranded in the dark at night.
Overall no regrets, she is happy and the performance of the packs has been flawless.
 
Here is a fairly current list of all AC, DC and SA commercial batteries. Not all are available in the US but the availability & number of products is increasing and this listing is updated frequently to reflect that. If you are "Wallet Heavy" you can go the Rolls Royce route or if you are just an average Jow just trying to get along there are good brands at good $ values as well (EG4 as one example).


FYI, only a few months ago no one heard of Server Rack Mount Batteries but Telecom Batteries (which these are) became popular as Server Rack Batteries and well there came the "product line" which is trendy "now" and therefore more demand = more $ and so the circle of commerce continues. Tesla's PowerWalls also was a contributing factor in making such happen, which is a good thing.

NB: Please, do NOT confuse a Tesla PowerWal with any Server / Telecom Rack battery. The only thing in common for real, is they are battery storage systems, there is a heap load more to a PowerWall than just Battery & BMS. A Different Animal, very much so.

Final Note: INSURANCE !
What a FUGLY Beast Insurance Co's are ! Cautiously and carefully inquire what your insurance co will want in order to cover your Solar / Battery installation. Some are a ROYAL PITA and demand everything be listed, pro installed "only" with heaps of paperworkd & inspections, while others are more reasonable. You really would not want to install anything that VOIDS Insurance ! AND let's be perfectly honest here, any excuse an Insurance Co can find to not pay out will be used and they are really getting bad about that... there are horror stories about with insurance.

Hope it helps, Good Luck.
 
Here is a fairly current list of all AC, DC and SA commercial batteries. Not all are available in the US but the availability & number of products is increasing and this listing is updated frequently to reflect that. If you are "Wallet Heavy" you can go the Rolls Royce route or if you are just an average Jow just trying to get along there are good brands at good $ values as well (EG4 as one example).


FYI, only a few months ago no one heard of Server Rack Mount Batteries but Telecom Batteries (which these are) became popular as Server Rack Batteries and well there came the "product line" which is trendy "now" and therefore more demand = more $ and so the circle of commerce continues. Tesla's PowerWalls also was a contributing factor in making such happen, which is a good thing.

NB: Please, do NOT confuse a Tesla PowerWal with any Server / Telecom Rack battery. The only thing in common for real, is they are battery storage systems, there is a heap load more to a PowerWall than just Battery & BMS. A Different Animal, very much so.

Final Note: INSURANCE !
What a FUGLY Beast Insurance Co's are ! Cautiously and carefully inquire what your insurance co will want in order to cover your Solar / Battery installation. Some are a ROYAL PITA and demand everything be listed, pro installed "only" with heaps of paperworkd & inspections, while others are more reasonable. You really would not want to install anything that VOIDS Insurance ! AND let's be perfectly honest here, any excuse an Insurance Co can find to not pay out will be used and they are really getting bad about that... there are horror stories about with insurance.

Hope it helps, Good Luck.
That list is kind of old and there are way to many NMC batteries included in the list.
I agree with you that Homeowners Insurance is a big issue. If a persons finances for the project are low then yes it's probably a good idea to see what the Insurance company says and to get it in writing. If you do have the Money then go with a Tier one battery pack with all of it's certifications. That way you will have no issues with the utility company or your insurance company. BTW it's hard to believe but Fortress is actually a lot cheaper than most of the other solutions. I like the ARK batteries price point, I just wish I knew who they got their cells from.
Also I do not like the 5 year warranty, it's half the time of the industry standard.
 
FYI, only a few months ago no one heard of Server Rack Mount Batteries

Rubbish. The earliest Pylontech server rack battery setup i’ve seen in action was installed in 2014. BYD B-Box was launched in 2017.

They were both made using cheap cells and ancillaries, and have proven to have a shorter lifespan than a pack compromised of quality cells (eg Winston).

They are convenient, but more expensive and less reliable than a well made DIY system. Of course the vast majority of DIY systems are not well made.

You need to get a system that suits your precise needs. If you don’t have the skills and understanding to put together a DIY system the server racks may be a good option.
 
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