Battery Bank - sourcing and set up

[JosephBr108]

Hello all!

I'm new to solar systems and am installing one in my RV. I'm planning on ordering 6 or 8 of these batteries: https://www.alibaba.com/product-det...4520d22qNJc8&bypass=true&fullFirstScreen=true

First of all, do you think these are good batteries to purchase vs the more mainstream method of purchasing battleborn batteries? Also, once I'm ready to order these batteries from Alibaba, does anyone know what Trade Terms I should select? It's been recommended I ship by sea, but for the Trade Terms should I ship EXW or FCA or FAS or FOB or CFR or CIF etc??

I want to wire 4 of them in parallel to get 12V 280AH. BUT, can I wire two more in series to maintain 12V but increase the overall battery bank capacity? OR would I just have to purchase 8 of them and make two, 12V 280AH batteries?

In ADDITION, I've got some questions regarding my general solar system set up.

A picture of my wiring diagram is attached. I've essentially copied this wiring diagram - https://faroutride.com/interactive-wiring-diagram/

I'm planning on purchasing 4 of these 175 watt panels (here) and wire them in a series. To accommodate this system, I need an 80 amp charge controller and am planning on getting one of these (here).

Questions:

1. How do I determine the the size of each circuit breaker needed? (I'm still figuring our needed wire gauges so am not worried about that yet.)
2. What is this terminal fuse for in their diagram?
3. I've read that for an 800 solar watt panel set up, I would need a 300+ amp hour lithium battery. The total amp hours of the battery bank I'm purchasing is 280AH. Is it actually necessary for me to have a larger battery bank for this system (700 watts from panels) or is that a nice-to-have given the larger capacity to generate electricity and store it?
4. Do you know what this the solenoid shut off valve for propane does? I'm trying to figure out if I need it.

I've learned a lot, but all of the sudden trying to put it all together feels like a daunting task. I'm hopeful that it will click. I'm trying to just focus on one section at a time, but I do have to essentially comprehend the entire system before I can order all of the necessary parts.

Thank you all for your help!

 

[Forbisher]

You connect four 280Ah x 3.2 volt cells in Series to get 12.8 volts at 280Ah
You can not add two more 3.2 volt cells to four 3.2 volt cells that are connected in Series.

You could parallel connect four more 280Ah to the four cells at 3.2 volts then Series connect those making a eight cell 560Ah 12 volt battery Or make two separate 4 cell 12.8 volt batteries.
You will need a BMS.

Your 175 watt panels are only about 10 amps each so four panels in Series are still only 10 amps total so why do you think you need a 80 amp SCC?
That Outback is overkill for your 4 panels.

The 280Ah batteries from Xuba have very long threads about them here with how to order.

 

[Forbisher]

First determine the size of your battery bank by figuring out what your daily usage will be and allow for how many days without sun you want to have capacity for.
Then calculate how many panels needed to charge your battery bank on available sun hours
Those 175 watt panels may not be your best choice.
Once you decide on panels you can choose and size a SCC and panel connections.

 

[Steve_S]

FIRST: DO NOT BUY ANYTHING !!!
Have a plan and understand everything from the bottom up beforehand. Failure to Plan is a Plan to Fail. (and it can get very costly)

It is an RV so sticking to 12VDC makes sense as it's already wired to use that and 120VAC as well (I assume).
My suggestion / recommendation is always KISS (Keep It Simple Silly) and don't get over complicated.
I would suggest two, 12V/280AH setup in parallel giving you 560AH gross @ 12VDC with 120-150A BMS
- (gross = 100% full use, normally we keep between 80-90% max use to maximize lifecycles)
- * two packs gives some redundancy & fall back if something goes awry.
For an Inverter/Charger I would highly recommend the Samlex EVO 3012 which is a Pure Sine, Low Frequency 3000W, 12V Inverter/Charger combo with built in ATS, Solar Input port and TWO AC connections (one for shore power, one for genset). These will auto-sense shore power, and switch over to it to charge the battery bank & provide pass through power simultaneously.
REF: https://www.samlexamerica.com/products/ProductDetail.aspx?pid=573 See Link in my signature for a brief overview.

The FlexMax SCC is Tier-1 Good Quality product but I have to say RED FLAG on that price... it's too good ! These normal retail around $800 USD +/- for sales / specials. I have seen factory returns, refurbished & used units at that price, make sure it is New Unopened WITH Warranty (grey market ones have no warranty, factory refurbs have limited warranties).

Solar Panels: Realize that 12V panels cost typically 2X what normal 24V+ panels do and most certainly do not produce the same amount of juice. The voltage of the panels is moot relative to battery as the SCC converts to the Batt Voltage, having 150VDC @ 30A off the panels to charge batteries is pretty normal actually. Now I certainly would not suggest 72 Cells solar panels but good 60 Cell panels are used on RV's and boats too. 60 Cell panels are usually 3' wide by 5-1/2' long. Usually people go for the smaller panels at greater cost due to space issues or having to work around things (roof AC for example). You may want to have a peek at https://store.santansolar.com/product-category/solar-panels/ and give it some thought. Jinko, Canadian Solar & SunPower offered on the site are tier-1 class panels.

hope it helps,
good luck
Steve

 

[JosephBr108]

FIRST: DO NOT BUY ANYTHING !!!
Have a plan and understand everything from the bottom up beforehand. Failure to Plan is a Plan to Fail. (and it can get very costly)

It is an RV so sticking to 12VDC makes sense as it's already wired to use that and 120VAC as well (I assume).
My suggestion / recommendation is always KISS (Keep It Simple Silly) and don't get over complicated.
I would suggest two, 12V/280AH setup in parallel giving you 560AH gross @ 12VDC with 120-150A BMS
- (gross = 100% full use, normally we keep between 80-90% max use to maximize lifecycles)
- * two packs gives some redundancy & fall back if something goes awry.
For an Inverter/Charger I would highly recommend the Samlex EVO 3012 which is a Pure Sine, Low Frequency 3000W, 12V Inverter/Charger combo with built in ATS, Solar Input port and TWO AC connections (one for shore power, one for genset). These will auto-sense shore power, and switch over to it to charge the battery bank & provide pass through power simultaneously.
REF: https://www.samlexamerica.com/products/ProductDetail.aspx?pid=573 See Link in my signature for a brief overview.

The FlexMax SCC is Tier-1 Good Quality product but I have to say RED FLAG on that price... it's too good ! These normal retail around $800 USD +/- for sales / specials. I have seen factory returns, refurbished & used units at that price, make sure it is New Unopened WITH Warranty (grey market ones have no warranty, factory refurbs have limited warranties).

Solar Panels: Realize that 12V panels cost typically 2X what normal 24V+ panels do and most certainly do not produce the same amount of juice. The voltage of the panels is moot relative to battery as the SCC converts to the Batt Voltage, having 150VDC @ 30A off the panels to charge batteries is pretty normal actually. Now I certainly would not suggest 72 Cells solar panels but good 60 Cell panels are used on RV's and boats too. 60 Cell panels are usually 3' wide by 5-1/2' long. Usually people go for the smaller panels at greater cost due to space issues or having to work around things (roof AC for example). You may want to have a peek at https://store.santansolar.com/product-category/solar-panels/ and give it some thought. Jinko, Canadian Solar & SunPower offered on the site are tier-1 class panels.

hope it helps,
good luck
Steve

WOW! Very helpful. thank you very much Steve.

I'm looking into the Samlex EVO 3012. Do you know off hand how much it costs?

You're right about the FlexMax SCC. People in the commentary says it came with no warranty and is indeed refurbished, but there don't seem to be any complaints of it not working. This product is linked (to Amazon) in Will Prowse's website - https://www.mobile-solarpower.com/the-off-grid-king-power-anything.html. Do you agree with MBR (above commentator) that this SCC is indeed overkill for my set up?

- I'm still needing to clarify the size of each breaker and what terminal fuses I need. I am using this diagram as my primary reference https://faroutride.com/interactive-wiring-diagram/

- Do you think I do indeed need 300+ AH battery bank for a solar panel close to 800 watts, as referenced in Will Prowse's website for The Off Grid King set up? https://www.mobile-solarpower.com/the-off-grid-king-power-anything.html

- As for the solar panels, do you recommend 60 cells simply due to size? So, it sounds like more volt output for the solar panel set up is optimal? Do you recommend greater than 24V panels? Those Jinko panels seem to be a really good buy, I haven't seen brand new 400 Watt panels for $200.

Side note, so I'm assuming you do consider those batteries from Alibaba to be a good buy? I have read some of the threads on this forum for these Xuba batteries. Seems like a safe buy? I'm am planning to purchase 8 of them to create 2, 12V 280Ah batteries.

I really appreciate the help! Finding people willing to shell out thorough advice on this stuff from anyone not belonging to a company has not been an easy find.

 

[Steve_S]

WOW! Very helpful. thank you very much Steve.

I'm looking into the Samlex EVO 3012. Do you know off hand how much it costs?

You're right about the FlexMax SCC. People in the commentary says it came with no warranty and is indeed refurbished, but there don't seem to be any complaints of it not working. This product is linked (to Amazon) in Will Prowse's website - https://www.mobile-solarpower.com/the-off-grid-king-power-anything.html. Do you agree with MBR (above commentator) that this SCC is indeed overkill for my set up?

- I'm still needing to clarify the size of each breaker and what terminal fuses I need. I am using this diagram as my primary reference https://faroutride.com/interactive-wiring-diagram/

- Do you think I do indeed need 300+ AH battery bank for a solar panel close to 800 watts, as referenced in Will Prowse's website for The Off Grid King set up? https://www.mobile-solarpower.com/the-off-grid-king-power-anything.html

- As for the solar panels, do you recommend 60 cells simply due to size? So, it sounds like more volt output for the solar panel set up is optimal? Do you recommend greater than 24V panels? Those Jinko panels seem to be a really good buy, I haven't seen brand new 400 Watt panels for $200.

Side note, so I'm assuming you do consider those batteries from Alibaba to be a good buy? I have read some of the threads on this forum for these Xuba batteries. Seems like a safe buy? I'm am planning to purchase 8 of them to create 2, 12V 280Ah batteries.

I really appreciate the help! Finding people willing to shell out thorough advice on this stuff from anyone not belonging to a company has not been an easy find.

I don't know how much a Samlex EVO 3012 sells for, they are not bargain / value grade equipment.

Nothing wrong with having a more capable SCC than you need at the start - things change and upgrades happen. IMO it isn't overkill. BUT I am corned with Grey Market / Refurbs...

800W of panel is not that much and let's face it, the top of an RV etc is not optimal placement unless you are at the Equator and even then. I know a lot of folks go for the smaller 12V panels for RV and Boats but they are crazy priced compared to he 24V+ panels. Mounting can be a problem, would not want them to become sails at 60 MPH or have them fly off into a cops windsheild. You would have to know how the RV'ers use them and what is best really. 400W+ Panels are too new to be in the used supply side, they are usually 72 Cell and most often bi-facial.

I started the second thread on XUBA's (link in my signature) and am using 280Ah cells from them.

 

[JosephBr108]

I don't know how much a Samlex EVO 3012 sells for, they are not bargain / value grade equipment.

Nothing wrong with having a more capable SCC than you need at the start - things change and upgrades happen. IMO it isn't overkill. BUT I am corned with Grey Market / Refurbs...

800W of panel is not that much and let's face it, the top of an RV etc is not optimal placement unless you are at the Equator and even then. I know a lot of folks go for the smaller 12V panels for RV and Boats but they are crazy priced compared to he 24V+ panels. Mounting can be a problem, would not want them to become sails at 60 MPH or have them fly off into a cops windsheild. You would have to know how the RV'ers use them and what is best really. 400W+ Panels are too new to be in the used supply side, they are usually 72 Cell and most often bi-facial.

I started the second thread on XUBA's (link in my signature) and am using 280Ah cells from them.

Just put in my order for 8 of XUBAs 280Ah cells. Payment is pending.

Roger that. So, mind me asking what 80 amp SCC you would recommend?

Gotcha, yes haha. Definitely would want to try and avoid having panels fly off my roof on the freeway. I'm going to call SanTan tomorrow to see if they have recommendations for the roof of my RV. Thank you for the reference. They have some of the best priced panels I've seen so far.

 

[jwelter99]

One word of advice.... do not blindly follow the advice to build multiple 12V batteries with separate BMS and parallel them. This is a simple DIY approach but very far from optimal and best practice. Spend some time researching this in detail. This forum is a great source of advice and ideas; but also much is opinion based on "it is how I do it so it must be best".