question

@Jack Reeves Just a smal reflection, as you speak about flooded lead acid batteries, do you check regularly the flood levels? This can influence badly the performance of the battery and shorten his lifetime.

The amount of absorption time the charger applies to your batteries varies according to the batteries minimum voltage.

Hi Jack ... Long short story... What is the angle used for your panels ? around 30-35 degrees ? That's the setting used for summer, and in winter the sun light comes with a different angle. By putting your panels at 60 degrees, you will increase your power input for your battery bank. I presume the panels are facing south, so if you have an opportunity adding 1 or 2 more panels, west orientated, you will get the missing needed power. Just install them as a new array and in parallel with your first array. You'll get around 3 extra hours of power to recharge the battery bank.

I had such issues with my first setup and did correct it this way.

Michel

Your voltage at 11.4 to 11.5 every morning is worrying. As mentioned above your Absorption time is calculated by the minimum voltage at the start of charging each day. As your battery voltage is dropping very low each day it either means you are unable to charge the batteries to full each day, leaving a deficit and potentially damaging your batteries. or your load is to large for your battery bank. either way this will lead to problems in the long term. You need to ensure that your solar array is large enough to charge your batteries to full and for longevity on lead acid bateries size your battery bank or reduce the load to get dod to between 40 & 50% max.

Can you confirm if you have managed to charge the batteries to full using your inverter charger and a generator and how this affects the start voltage the following day.

I will second that you are running your batteries too flat. They should last longer if you reduce the use and add more panels. That's really flat for each day of use!

The problem immediately with flooded banks and not treating them right is it is difficult to add more batteries in LATER (like now) after you have already reduced the initial lifespan and ability to hold a charge for a longer time!

1) immediately learn how to use your battery fluids testers and do it! Do NOT let anything fall into those holes (can explode) nor reach in to pull something out EVER (NO metal!)

2) reduce your loads ASAP

3) ADD 2 more panels. Even used grade b ones to bring the voltage and amps up will help tons!

4) run the generator early in the morning and again half way through the evening and again for BULK charging and run if possible to coincide when tapping the batteries for your higher loads -usually flooded batteries ae slow to charge and a generator is more expensive to run and does BEST for bulk charging!

Use solar for absorb and float until you have enough sun or panels to solve the charging issues! Otherwise you'll need 4 new batteries and that will be far more expensive than anything above.

A way to think about it is: you need x power per day; the batteries last longest and work best near full (or at least above half-way flat). You have to charge the batteries ANYWAY to replace x power + at LEAST 10+% more regardles (if you want them to last)

So....why not keep them charged or close to it most of the time so they last (vs drained daily and 1~2 years of productive use)?

You have to get that power in from somewhere, so which is better for YOU; more panels, and/or morning generator use and reducing loads -or- new set of 4 more batteries in the spring (and more panels next winter)?

Don't let let them go below 12v after no loads for 45 min until you get the hang of how you are taxing them and how to keep them charged for long-term use. Mine have lasted 10 years so far but I have only deep-cycled them maybe a dozen times max. so far!