Just some questions about batteries guys. We have 16 US Batteries equivalent of trojan L16s or close to them. I would need to look it up to get the exact model number. They are 9 and 7 years old. They would run the house durring the day but only while there was sunlight, after that they would quickly drain charge, we would typically be using somewhere around 30 to 40 amps load on a 24volt battery bank. I did the math once and I remember thinking that they should last for about a day. We are using an Old DR inverter and they only seem to last about 4 hours after sunset. Last Night I wired the inverter to be able to charge from the grid for the first time and today we equalized the batteries with about 80 amps of current as opposed to the 22 amps that we recieve maximum from the array. I use to know alot about batteries back in High School, when I worked with the electric car program, but I seem to have forgotten most of it. They appear to be lasting better now after today's equalizing. Is there something we should be watching out for, or something we should be doing to improve thier performance? We kept them charged and equalized them with array for for the first 9 years but very seldom did we actually cycle the batteries to the extent that they we made for. At least to the best of my knowledge this is true. So my I guess my question is, is there method for equalizing betteries to get as much of thier performance back as possible or have we done everything that we can? Right now Without load, they stay around 27.5 volts. All cell levels are full.

sounds like they're just getting older and can't deliver their full ratings anymore. eqing helps keep everything full and equally charged and maintenance intervals should be increased gradually.

9 years is pretty close to end of life for L16 sized batteries ...

The basics are you have to know your loads and compare to your charging source ... allow for no more than 60% discharge and 65% overall efficiencys

Battery are rated for number of discharges and vary based on discharge amount. You get more cycles the shallower the discharge cycles.

Even if floated for there life, there are other thing that kill batterys and for LA, your already on borrowed time

Thats pretty much what I thought. We will do our best to squeeze the last of the life out of these that we can, but in a couple years I will probably need to replace them. They still charge to 30v on equalize and between 27 and 28 volts durring normal charge but they never seemed to perform to thier specifiecations on discharge. Maybe we just put more load on them then I realized over the years. They were hardly used for the past 6 years of thier life, just in the event of power outage and occationally when we worked on the main ac box (Grid disconnected). They also never had enough power to have properly equalized the batteries until now. Although for the first 2 or 3 years my father used the batteries for backup and for an alternative to grid power to try to reduce our light bill, but stopped when we had 3 computers going most of the time, it was just too much load. They were probably cycled pretty heavily in those first 3 years.

yes, i meant to add that new batteries should be on the horizon and don't mix any new ones with those old ones even on a temporary basis.