Lithium Titanate
Hi All, I got a quote on Lithium Titanate "Max discharge rate is 10 C so 900 amps for 90 ah and 1200 amps for 120 ah The 120 will be 30% more expensive than the 90. Price for 90 ah is $150...
Forum Discussion
3 tons,
The issue with solar charging seems to be the capacity of the charge controllers. An 80 amp is $600 to $800 smackers. There are a few 100 amp controllers, but at least one of them is a "swindle" as it can't do 100 amps at 12 volts. So even a single LiFePo4 is going to exceed what solar can produce.
Suppose we take 14.6 as the "bulk" voltage. 80 x 14.6 = 1168 watts.
The same sort of limit happens with converters and inverter/chargers. Assuming 200 amp-hours of Li the power factor corrected Magnum maxes out at 127 amps. 127 x 14.6 = 1874 watts--so it would exceed what a 15 amp circuit could handle. So, I would have to scale back the voltage to 14.1. Or if I wanted the 14.6 volts, I would have to limit the Magnum to 123 amps.
So faster charging is not really going to be that much faster, especially with a large bank.
I would not think any serious boondocker would have less than 2 to 3 hundred amp-hours.
So the only "real" chemical advantage of the LI is that they don't sulphate.
The "physical" advantage is that they weigh a lot less than flooded batteries.
I want 600 amp-hours of SiO2. They would charge at .25 C or 150 amps. I have no way to provide them with 150 amps.
I know that BFL13 noted tapering on SiO2--but I do not know if he was charging at 14.6 volts. They, too, do not suffer from sulphation. Their ability to be used at -40 is needful for me--and I won't have to jump through hoops to prevent alternator damage, nor use dc to DC charge devices (though that would be a benefit, given my business use where I might well drive for 5 hours in a day).
I just today found out that SiO2 are lighter than flooded batteries of similar capacity. They are a bit cheaper than LiFePo4 from places such as Battleborn or Lion.
If you "roll your own" LiFePo4 then we get to about $368 USD. The folks at Lac La Biche quoted $313 (usd) for a drop in 12 volt 100 amp-hour with BMS.
The issue with solar charging seems to be the capacity of the charge controllers. An 80 amp is $600 to $800 smackers. There are a few 100 amp controllers, but at least one of them is a "swindle" as it can't do 100 amps at 12 volts. So even a single LiFePo4 is going to exceed what solar can produce.
Suppose we take 14.6 as the "bulk" voltage. 80 x 14.6 = 1168 watts.
The same sort of limit happens with converters and inverter/chargers. Assuming 200 amp-hours of Li the power factor corrected Magnum maxes out at 127 amps. 127 x 14.6 = 1874 watts--so it would exceed what a 15 amp circuit could handle. So, I would have to scale back the voltage to 14.1. Or if I wanted the 14.6 volts, I would have to limit the Magnum to 123 amps.
So faster charging is not really going to be that much faster, especially with a large bank.
I would not think any serious boondocker would have less than 2 to 3 hundred amp-hours.
So the only "real" chemical advantage of the LI is that they don't sulphate.
The "physical" advantage is that they weigh a lot less than flooded batteries.
I want 600 amp-hours of SiO2. They would charge at .25 C or 150 amps. I have no way to provide them with 150 amps.
I know that BFL13 noted tapering on SiO2--but I do not know if he was charging at 14.6 volts. They, too, do not suffer from sulphation. Their ability to be used at -40 is needful for me--and I won't have to jump through hoops to prevent alternator damage, nor use dc to DC charge devices (though that would be a benefit, given my business use where I might well drive for 5 hours in a day).
I just today found out that SiO2 are lighter than flooded batteries of similar capacity. They are a bit cheaper than LiFePo4 from places such as Battleborn or Lion.
If you "roll your own" LiFePo4 then we get to about $368 USD. The folks at Lac La Biche quoted $313 (usd) for a drop in 12 volt 100 amp-hour with BMS.
