FLA replacement help

[Yvan]

Hello, at the moment I have 8 x 6v 235 ah fla batteries wired for 12 v in my bus. I would like to upgrade to LiFeP04 batteries, and support Will while I’m at it.

I have no issues assembling a battery bank from components purchased from Will. I would like a battery bank that’s at least as powerful as what we have. Our system is set up for 12v and would like to maintain that aspect of our system.
In short I need batteries, BMS with cold protection and everything needed to join them all together. Safety is my priority.

Here is a little description of our system

https://www.facebook.com/1762164787435935/posts/1882910412028038

 

[Steve_S]

Theoretically you have 940Ahrs of useable lead @ 50% DOD to replace.
Your likely going to need to improve on the amount of panels to be able to fully charge your batteries, I can't imagine with only 4, 320's you ever had the lead fully charged in a day (the only way to really verify that is with a Hydrovolt testing of the gravity in every cell).

 

[Yvan]

Theoretically you have 940Ahrs of useable lead @ 50% DOD to replace.
Your likely going to need to improve on the amount of panels to be able to fully charge your batteries, I can't imagine with only 4, 320's you ever had the lead fully charged in a day (the only way to really verify that is with a Hydrovolt testing of the gravity in every cell).

Normally by 10 am we are fully charged and in float charge mode. Also most days we are on the road, so the alternator helps in charging as well. The only time we could need more is when we run the mini split A/C all day
How much capacity of LiFeP04 batteries do you recommend?

 

[SolarRat]

Nice setup. If it's working well why change?

 

[Steve_S]

Normally by 10 am we are fully charged and in float charge mode. Also most days we are on the road, so the alternator helps in charging as well. The only time we could need more is when we run the mini split A/C all day
How much capacity of LiFeP04 batteries do you recommend?

You're the one to know how much you use per day and how much autonomy you want IF you cannot generate or get power to recharge (say alternator fails, someone steals genny etc not likely but you never know) I figured you had 940Ahrs usable right now, that's a LOT of lifepo, ie the equivalent of 9 Battleborns @ $1,000 each. Do you need that ? I dunno, you do. At least you have a good solid baseline as to your usage with the experience you have using your batteries & system as configured.

 

[SolarRat]

Theoretically you have 940Ahrs of useable lead @ 50% DOD to replace.

8 x 6v 235ah would be 470ah @ 50%....So 400-500ah of LFP should do.

 

[Steve_S]

8 x 6v 235ah would be 470ah @ 50%....So 400-500ah of LFP should do.

Ohhhh crap I fell asleep at the wheel, LMAO
24V. 4 x 6v @235Ah = 24V@235 + 1 Parallel bank @235Ah for a total 24V/470Ah

Yvan does not mention IF that 235Ahr rate is at 20Hr or not.
My own FLA bank is 8x 6v/428Ahr@20 set as 4s2p giving me 24V / 856Ahr@20 gross or 428Ah useable @ 50% DOD
using Rolls Surette S-550's.

 

[Yvan]

You're the one to know how much you use per day and how much autonomy you want IF you cannot generate or get power to recharge (say alternator fails, someone steals genny etc not likely but you never know) I figured you had 940Ahrs usable right now, that's a LOT of lifepo, ie the equivalent of 9 Battleborns @ $1,000 each. Do you need that ? I dunno, you do. At least you have a good solid baseline as to your usage with the experience you have using your batteries & system as configured.

If I could get 8-900 Ah that would be amazing, but the reason I posted here is to get a list of what I need to do it safely, but without paying for brand name batteries.

 

[Yvan]

Nice setup. If it's working well why change?

The lead acid batteries are at the end of their useful life. We are in our bus almost full time, so it goes through about 300-320 charge/discharge cycles per year. They are close to 1000 cycles as we speak.

 

[Steve_S]

My bank of FLA's are dying as well after a hard life and semi-abusive maintenance. So step one was a 24V/400AH LFP pack (see ShunBin thread in my sig, What an experience but learned tons). If you build yourself 2x 560AH packs (16x280AH 8S2P) one BMS per pack you'll get the most bang for buck. Your looking at $2200 USD plus BMS, fusing and any casing you may want.

280AH cells Below

Szxuba Grade A Eu Stock Rechargeable 3.2v 280ah Lifepo4 Lithium 280ah Energy Storage Battery Cell - Buy Lifepo4 280ah Battery,Eu Stock 280ah Lifepo4 Battery Cell,Lifepo4 280ah Product on Alibaba.com

Szxuba Grade A Eu Stock Rechargeable 3.2v 280ah Lifepo4 Lithium 280ah Energy Storage Battery Cell - Buy Lifepo4 280ah Battery,Eu Stock 280ah Lifepo4 Battery Cell,Lifepo4 280ah Product on Alibaba.com

www.alibaba.com

Or IF you want 24V/300AH 16x152AH Cells in 8S2P @ $1363 USD plus BMS, Fusing & wire.

This product is no longer available.

This product is no longer available.

www.alibaba.com