Lithium Iron Phosphate batteries are the future without a doubt mainly because they last longer, charge quicker and can discharge to 100 percent with no damage. There are some downsides though and we wish to make you aware of them.
Currently the technology is new and we don’t know how long they’ll actually last though best guess is at least twelve years though a number of commercial lead acid batteries will easily last that long.
They are expensive and the cheaper ones available are mass produced in China by companies that may not be around in ten years. Prices will come down eventually but we’re not there yet.
The biggest problem we at Land and Sea Solar see with them is the lack of compatibility with the other components such as the inverters and solar charge controllers and the difficulty in determining how full the batteries are. This all comes down to the battery’s Battery Management System or BMS and it’s ability to communicate with the inverter and the state of charge (SOC)meter. If all the gear is integrated and communicates fully with each other that is called Closed Loop Communication. That’s the only way the inverter’s meter can accurately report how full the battery bank is and the most accurate way for the solar to charge the batteries.
We refuse to sell or install any lithium system that can’t closed loop communicate. Now here’s the problem, most of the batteries flooding the market don’t close loop their BMS with most of the inverters available. It’s like the left hand doesn’t know what the right hand is doing and that’s the current situation. Some battery companies are getting ready to make their own inverters but currently the good choices are few and far between. For off grid systems the choices are even fewer.
One popular but expensive choice is the Sol-Ark inverter paired with SimpliPhi batteries. Fortress was offering a battery that closed looped as well but they quit supporting that as they plan to launch their own inverter. We don’t endorse being the first person on your block to try any new product and we prefer a wait and see approach regarding new offerings.
Schneider also allows for Close Looping with a few brands and models of battery but we find Schneider lacking and cumbersome in some of their system integration and navigation and we are leaning towards the Sol-Ark systems at this point.
If you can wait, then please wait and prices will come down and the companies will eventually get sorted out on their offerings.