The biggest problem with NiFe batteries

Almost all large rechargeable deep cycle batteries in keeping use are Lead-acid type. (You will find some NiCads being used, however for most reasons the high initial expense, and also the high cost of disposal, doesn't justify them). A couple of Lithium-Ion types are beginning to create the look of them, but they are a lot more costly than Lead-acid and many charge remotes don't have the right setpoints for correct charging.
The acid is usually 30% Sulfuric acid and 70% water at full charge. NiFe (Nickel-Iron) batteries can also be found - these possess a lengthy existence, but instead poor efficiency (60-70%) and also the currents will vary, which makes it harder to match with standard 12v/24/48v systems and inverters. The greatest trouble with NiFe batteries is perhaps you can have to set up 100 w to obtain 70 w of charge - they're a smaller amount efficient than Lead-acid. That which you save money on batteries you'll have to compensate for by purchasing a bigger cell system. NiCads will also be inefficient - typically around 65% - and incredibly costly. However, NiCads could be frozen without damage, so might be sometimes utilized in places that the temps may fall below -50 levels F. Most AGM battery will even survive freezing without any problems, despite the fact that the output when frozen is going to be little or free.