Van Build - Need help on Solar

[Stephen Shreds]

Hey everyone!

I just recently purchased my Ram Promaster 2500 159" WB.




I have been trying to plan my solar setup around my computer. This is the setup I am thinking of building.

--------------------------------

3 - 300w Renogy panels: https://www.amazon.com/gp/product/B07K43DZFR/ref=ox_sc_act_title_6?smid=A05654602L3XUQ70M87BV&psc=1

1 - solar Charge Controller 150v/50a: https://www.amazon.com/gp/product/B07KB4N13B/ref=ox_sc_act_title_4?smid=A2P9F29Y7BYBUO&psc=1

1 - 2000w Inverter: https://www.amazon.com/gp/product/B07GDH711G/ref=ox_sc_act_title_1?smid=A1SK9IS6JDBCLC&psc=1

1 - Battery protector: https://www.amazon.com/gp/product/B07PJ1LJFR/ref=ox_sc_act_title_1?smid=AERMGYAT5R869&th=1

1 - Temperature/Voltage Sensor: https://www.amazon.com/gp/product/B07FK6H3YF/ref=ox_sc_act_title_3?smid=AERMGYAT5R869&psc=1

--------------------------------

With all this being paired up with the 2 24v battery pack the I will build.

8 - 200ah lithium power cells: https://www.amazon.com/gp/product/B07P6XVRG1/ref=ox_sc_act_title_5?smid=A2UWFUXH0IWODZ&psc=1
1 -80a 24v daly seperate port bms: the one will links to in his list.
Now my questions are with all these added together will I still have only 200ah at 24v? If so would I have to buy 16 of these to get 400ah?

When separating those to two batteries = 2 - 8 cell packs how do you attach two bms to solar? Each bms attached to each battery with the negative end going to a negative bus bar. Then each positive to a dedicated solar bus bar going to the positive terminal in the solar charger.


If you have a setup close to this let me know how it works!
Thank you for the help in advance.

Shreds.

 

[Will Prowse]

Watch this video:

Use one BMS (as in video). And use a common port BMS. And connect solar charge controller directly to battery bank.

Run the loads through the BMS.

Now the tricky part. Connect solar charge controller directly to LiFePO4 battery bank. Charge the battery bank up until one of the cells hits 3.65v. Check voltage of entire battery bank, and use this voltage as the upper limit voltage of your pack. Set it as absorption on your SCC. If cells are matched and healthy, this will work nicely for years to come. The cells will charge up until the lowest capacity cell is full, then charge controller wil stop charging. LiFePO4 can handle some over charging, so its safe. And it will never reach that point if you have good cells and upper limit voltage is set.

Did that make sense? I hope so. I need to make a video on it

 

[Stephen Shreds]

Hey will thanks for the reply! I am a visual learner so a video would be greatly appreciated!


From my understanding of the video
Connecting 8 200ah cells like that will increase my usable amp hours. Taking a 24v 200ah 8 pack dividing that into 4 12v 200ah 2 pack increasing my usable amp hours from 200ah to 800ah?

I think I got that. There wasn't numbers being thrown around in the video that's why I am guessing the amp hours.

Is there any reason why I should use a common port bms over the separate port bms?


Charge battery pack until one reads 3.65v. Then read the value of the whole battery we will call that number "X". Set max charge voltage to "X"
Not sure what absorption means in relation to SCC.

If cells are matched

Bottom balanced right?


If I am correct then I got it.

If not then I have a phd in D U M B

 

[Stephen Shreds]

Now the tricky part. Connect solar charge controller directly to LiFePO4 battery bank. Charge the battery bank up until one of the cells hits 3.65v. Check voltage of entire battery bank, and use this voltage as the upper limit voltage of your pack. Set it as absorption on your SCC. If cells are matched and healthy, this will work nicely for years to come. The cells will charge up until the lowest capacity cell is full, then charge controller wil stop charging. LiFePO4 can handle some over charging, so its safe. And it will never reach that point if you have good cells and upper limit voltage is set.

Would I need to choose a different charge controller? since 24v to 12v needs more amps?