These LiFePO4's are AWESOME

dexter12353

So some background - 2 years ago we decided to go down the route of Off-Grid.  I've posted in here a few times as I've made upgrades to the system.  When I originally did the buildout on the system, I went with 200ah 12v size 8D FLA batteries - And that was approx $6400 investment.  They worked well, At first.

Fast forward 2 years later - I have 3 pallets out back stacked with 8Ds, and only had 12 batteries properly functioning.  What a disaster.  Expensive mistake.

The problem came from a few sources - I moved out of state for work, and was no longer home to do proper maintenance.  The cells got rode hard and put away dry (Literally).  As a result, the capacity went through the floor and the generator was auto-starting anywhere from 3 times to 10 times per night - the batteries were holding practically nothing.

Struggle, struggle, struggle, until one of my youtube followers reached out to me and taught me about Prismatic lithium.

I was very hesitant at first as I feared for fires caused by battery packs - This was also part of my initial design choice to go with the lead acid batteries.  Come to find out that the prismatic LFP cells are far more stable than say, 18650 technology, easier to keep balanced, etc.

So here I am now, I got my first 100ah pack of LFP.  Yes, this pack is undersized for my loads and usage, however, it's a stepping stone to both learn from and to save up cash for a bigger bank.

These things are truly amazing, I am down to 1 generator cycle at night, which tells me they are holding at least 5x more usable power than the FLA's

Here's my install video: https://www.youtube.com/watch?v=EQZOCH6_3g8

Gullo

Hi there,

That looks like a fun build. You have a lot to be proud of! I'm wondering, though; why did you bottom balance the calb cells rather than top balancing? I see that you programmed your own PLC to serve as the programming for your BMS - - - ? Do I understand that correctly?