Originally Posted by turf
who has tried them, what's your experience? I'm looking at you JD!
I've been called out!!!
Mine are Lithium Iron Manganese Phosphate (LiFeMnPO4), or simply LFMP. I have 10,000 watt hours capacity configured as a 24 volt bank. This translates to 400 Ah @ 25 volts (or 800 Ah @ 12.5 volts). 85% of that is usable so about 680 amp hours. That is in in a rather small and light package of 230 pounds and 22” X 19”x 10”.
I LOVE THEM!! Of course, I paid a small fortune for them so I have to love them.
That said, I really do love them! They charge incredibly quickly, I don't have to worry about discharge rate (C-Rates) and damaging them, and there is zero maintenance (watering). The BMS is really nice as it takes care of the charging details as well as a high and low voltage cutout relays to protect the batteries and the "monitor" screen is very nice with all the data that it provides.
As always, I'd like to have more... maybe a 20,000 watt hour bank and 4,000 watts of solar?!?!?
For full-timing use, it is a fairly easy decision to go with lithium. Doing an apples to apples comparison is difficult but if you can get close, it is easy to see that Lithium is the way to go. One must compare actual usable hours, expected life (charge cycles), as well as how 'hard' you plan to run them. Its just that initial investment that is tough.
The only negative that I can think of is a shore/generator battery charger. I do not currently have one as there are no good ones available - yet. All of my charging is from solar and this has worked just fine for fourteen months. Still, I keep looking (and pinging the company from which I purchased the system). There are some options but none are plug and forget, as I would like. There are many folks with no/limited solar using lithium so they must be charging from shore power so there must be something available. Maybe they are abusing their investment?? I don't know, never been a priority so I've never spent significant time on it. Maybe there are more options for 12V lithium chargers than there are 24V (as I need).
I've run the new air conditioning from battery and it works just great! I also run a Samsung residential refrigerator 24x7, Samsung microwave/convection oven, NuWave induction cooktop, electric coffee maker, TV, Dish Wally receiver, lights, water pump, vent fans, laptop/phone chargers, CPAP machine, cordless drill/tools, band saw, radial arm saw, soldier iron, cell booster/amplifier, and all the other little things that one has around the house that requires electricity.
For comparison sake, to achieve the same usable Ah with 6V GC (golf cart) batteries one would need 14 batteries. That would weigh something around 850 lbs before building a rack system to hold all that weight. All of the interconnect cables would be interesting, watering them would be an all day project!
One would still be limited by C-Rate (both charge and discharge) and a string this long has some other issues that present some challenges/limitations.