Of course inverter batteries must be replaced and will not last forever except you are talking of recycling them. But we want to show you in this article, how you can make the batteries last longer than it would have.
As you know, batteries are perhaps the costliest investment you make in a solar/inverter power system installation. This means that frequent change of your batteries will incur a lot of cost and will destroy the argument that solar is cheap.
So how can we get the most out of our batteries before replacing them?
- Now the first thing is your inverter charger. This one is very important because the amount of charge your battery receives can affect its life span. Your inverter must be able to charge your batteries as fast as you use it. For example, if you do not have solar yet installed, you have to know that the inverter is the primary charger you have. In an example where you have 8 of 200AH batteries and you want to charge it with a 48V 20A charger, you will have a 48V 400Ah battery bank against 48V 20A. Ideally, it will take 400Ah/20A which is 20 hours to charge the batteries! Its actually more if you factor in other losses. So you see why your inverter size matters a lot.
- Charger settings: You must set your charger or inverter to cut off battery use at most 80% but preferably 60%. This applies especially to lead acid battery which do not tolerate very deep discharge. Batteries are measured in cycles against the percentage depth of discharge. The deeper you discharge, the more you reduce the cycle.
- System sizing: Please make sure you size your system appropriately. If your experienced installer recommends say 16 pieces of battery, do not buy only 4 pieces without reducing your load also significantly. Heavy load on battery will discharge it faster and reduce the life span.
- Ventilation: Batteries perform best in a well ventilated space. Make sure where the battery bank is installed is airy or air conditioned.
- Get a high quality battery: No matter how careful you are, a bad battery will always fail you. Make sure you purchase a well rated battery that is genuine and up to its rating. Good batteries perform better and last longer because some of them has patented technology that encourages the optimal interactions of the internal battery chemistry thereby prolonging its life.
- Install a solar system too: You will need to additionally add extra charging power from the sun to sustain your battery life. Installing panels will reduce the load on the battery especially during the day and this can double the life span of your battery.