I'm running an off-grid 24v hybrid charger/inverter with solar panels and 6 AGM 12v 100Ah cells arranged as 3 pairs in parallel, nominally giving 300Ah at 24v (7.2kWh), but sometimes, especially in the winter, the battery gets too low to run the coffee machine (needs 60A from the battery for a couple of minutes!).
I have enough solar panels to quickly get the battery up to 100% (reported by the charger/inverter's monitoring software) even in a short spell of sunshine, but I feel if I could store more then it would even out and compensate for the days when there is little or no direct sunshine.
I'm thinking of adding 2 or 4 more of the same cells, in pairs, hoping to lift the capacity to 9.6kWh or 12kWh.
I wonder if there are any potential issues I should consider before adding cells, so I asked at the company where I bought the originals.
The response suggests new cells would not play well with the old ones, even though they are less than 2 years old, and I'm advised to consider replacing the whole lot with new, and even switching to lead crystal instead of lead acid. That would be £3000 just to match the existing 7.2kWh, and another £1000 for each 100Ah uplift, where each additional 100Ah of AGM would be about £500.
I can't help feeling this is the sales guy selling, rather than helping me get the best to meet my needs.
So, I need impartial, expert advice regarding whether adding a new pair of cells (same manufacturer, chemistry, voltage, capacity, etc.) would be a problem.
And, if the problem is real, is there anything I can do when adding said cells to mitigate the risks.
All help gratefully received.
I have enough solar panels to quickly get the battery up to 100% (reported by the charger/inverter's monitoring software) even in a short spell of sunshine, but I feel if I could store more then it would even out and compensate for the days when there is little or no direct sunshine.
I'm thinking of adding 2 or 4 more of the same cells, in pairs, hoping to lift the capacity to 9.6kWh or 12kWh.
I wonder if there are any potential issues I should consider before adding cells, so I asked at the company where I bought the originals.
The response suggests new cells would not play well with the old ones, even though they are less than 2 years old, and I'm advised to consider replacing the whole lot with new, and even switching to lead crystal instead of lead acid. That would be £3000 just to match the existing 7.2kWh, and another £1000 for each 100Ah uplift, where each additional 100Ah of AGM would be about £500.
I can't help feeling this is the sales guy selling, rather than helping me get the best to meet my needs.
So, I need impartial, expert advice regarding whether adding a new pair of cells (same manufacturer, chemistry, voltage, capacity, etc.) would be a problem.
And, if the problem is real, is there anything I can do when adding said cells to mitigate the risks.
All help gratefully received.
