So, I have solar power system and it is as follows:
- 2 AGM batteries each 100 Ah
- 2 solar panels, 24 volts, 250 watts each
- a controller
- an inverter
the batteries are connected in series to give a total of 24 volts and 100 Ah which in total is 2400 Watts. On the other hand, the panels are connected in parallel because they are already a 24 volt system.
Now when I first started using my system I noticed that the total daily charge is around 20-40 Ah which to me was not logical because I expect the batteries to charge around 60-80 Ah on a daily basis since I use the batteries as much as possible before my inveters beeps.
After a while I noticed an unexplainable degradation in the system performance so I did some measurements.
During the charging phase while in sun light I have noticed that the two batteries had almost the same reading which was around 13.8V. However, after using the batteries for about 6 hours, I have noticed that one battery was reading ~12.4V while the other was reading around ~8.2V.
So I turned off my inverter and after a while the first battery still read ~12.4V while the other read ~10V.
Now I want to know what caused my batteries to degrade and what can be done about it.