pianotuna wrote:
Steve as far as advantages to, SiO2 don't need a way to protect an alternator, nor do they need more than a garden variety converter, or battery charger. So the space taken up by the SiO2 may be less than what is required for an LiFePo4, and so may be the weight--unless we are taking a pretty large bank.
you joking right? right now a 260 amp bank of 6v Si02 is 140 to 160 Lbs depending whoes weights you believe. a 280 AH LFP is 48lbs so that is two 6V batteries. that is just advertised AH, if we want to make that usable then we are looking at 210Ah of SiO2 to 252Ah of Lfp. so simular and not out of the question for a camper. a older one like mine couldn't do the SiO2 unless I put them inside.
the 6v SiO2 are normaly 783.95 each but on sale right now for 666.35. so 1572.00 ish + tax if you dont get them on sale, or about 1333.00ish if you are ready to buy now. not bad pricing for the larger capacity more heavy built batteries.
High cycle life – 2800 Cycles at 50% DoD
I can get the Lfp for about 1000.00 if you have to change out the converter section because you have a older unit that isnt Li compatable then add 200. my 5th and my camper both are Li compatable already with the converter and the solare so no extra for me.
high life cycle - 3500 cycles at 100% DoD ( close to 7000 at 50% DoD)
one fo the things that realy pushes me towards the LFP is the state of charge tables. the LFP battery wont drop below 12.5V untill it is lowered to 14% of its capacity, and it stays above 12V till around 2%. that means for inverter use and such you can draw the battery down much farther before you get stupid low voltage alarms. the Sio2 the voltage drops below 12.5 @ 50% depth of charge and drops below 12V @ 20% which is still pretty respectable concidering a normal lead acif drops to 12.5 @80% Dod and below 12V @ just under 50% DoD.
as for the charge from the battery. I dont use that on anything I own, as the newer trucks and altanators don't play well with any kind of battery so doesnt matter which battery I use a DC-DC charger is the only option for me. the smart altanators are very good at making your starting battery and altanator life better than in the old days but they suck when you use them to charge the camper batteries. so a DC to DC charger should be an upgrade for any type of battery if you want reliable charging with the new smart altanators.
even if you dont need one that can easily be tucked away anywhere (behind the power pannel in the camper the roof of a storage space, so as for taking up room thats a mute point also, but even if you stack everything up outside in a pannel the Lfp will still take up less apsce as it is only 12x6x8" where the SiO2 would be 22x7x10.5" if you went with the single 12V 270Ah SiO2 it is 10.59x 20.47x9.09", nice option but being one piece hard to put anywhere in a camper. for your 5th wheel that might be a good option though... and as I have said before in a 5th that is used like you do , then ya SiO2 are the better option for you.
For me not so much as I wont camp in -30C heck -10 is probably the coldest for me and having the LFP inside the heated camper it wouldnt matter what the temp is out side as long as I can run the furnace, so I guess -10 to -20 would be my cut off to get the furnace or a battery warmer going.
with the shipping prices of LFP coming down so much in the last year unless you have a reason like camping in the cold winter for extended periods with out your batteries in a heated space there is no reason not to go with the LFP. they are now by far the cheepest per usable AH out there. if you go for cycles at the same AH use they are probably 1/2 the cost of SiO2.
Either one for a older fellow like us will probably be the last battery we buy but who would have thought the day would come when we could pass batteries down to our kids?
Steve
