So im wondering why some are not using their packs? If you know there is calendar aging, and the battery is slowly dieing anyways, why not use it? Is it just because your overall usage is low and not necessary? If that were the case, why such a large bank? I guess for extended outages or extended sub-optimal PV days. Just thinking out loud here.
I just don't see why you would waste money letting the packs age on their own. Im genuinely curious.
Being off grid, I’m mindful of my usage. I could use my batteries maybe a little more, but we’re living comfortably at current usage levels. We built to our place energy efficient and bought the most efficient appliances we could.
I personally do not want to draw my battery down to 20 or 30% every night. What if you have a very bad PV day the next day, or two or three? To me, sunshine is free, propane for the generator to charge batteries, gets very expensive. I guess being completely off grid, having a prepper like mindset, my approach to this solar set up is just different. I have dual inverters, in case one gives a problem. Using a 16s4p battery pack, so that itself is a back up. If I need to work on one pack, I’ve got three more. I rather have plenty of power in reserve, rather than just barely get through each night?
My thoughts are, my current battery pack will last me a minimum of 10-15 years if not longer. So, hopefully, by the time it needs replacing, battery technology should be more advanced and maybe affordable?
Based on what I have seen and read about these LiFePo4 batteries, there seems to be a lot of uncertainty about how long they actually will last and how much they actually degrade. It seems that different folks with varying batteries have different results.
To add to it, I have more panels than I needed to hopefully account for panel degradation over the years and help collect more sunlight on cloudy days.
There’s a saying that says:
You got one, you got none.
If you got two, you got one.
Below is from a similar thread where I posted:
“So I’m running a 16s4p power-wall made of 64, 304ah cells with Batrium BMS. Set to 90% as my max full charge and 20% as my minimum. So far NO full cycles in 11 months off grid. However, the lowest SOC I’ve recorded is two nights, one at 53% and one at 56%. However, my average nightly draw down is typically between 65% and 75% so far, and that depends on the time of year”
