SiO2 Batteries and High Amp Draws
SiO2 is a specialty battery type that most folks would have no use for vs the usual RV battery types. They cost a lot too.( I had a special reason to get one)
Here is some info on them --I am not selling them!!! Just trying to show what they are
https://azimuthsolar.ca/product/12v-100ah-sio2-battery/
One big thing they are supposed to be good for is high amp draw loads for their size in AH. So here is what I found on that:
1. The 200AH bank (two 100s) with the 2000w MSW inverter and my wiring job has a voltage drop that stays about the same for the same load at any SOC above inverter shut-off voltage.
2. The MW draws about 55 amps and the kettle draws about 89 amps and the furnace in the TC draws about 3.5 amps.
So example using kettle to boil water for cup of instant coffee. (No advice needed on making coffee, you latte bunch, thanks anyway :) )
A. Monitor before start--142AH, 12.7 volts, 71% SOC
After start- 88.7 amps draw, 11.7 volts, about five minutes kettle off
Monitor now--135AH, 12.5 volts (rising slowly), 68%
So that time 89/142 is a 63% draw.
B. Before-- 113AH, 12.3 volts, 57%
-11.5v at 88a
-11.2v at 90.5a
-11.1v at 90.6a
After= 106AH, 53% SOC
So that time 90/110 is an 82% draw.
(note how inverter amps go up as voltage goes down--"inverter creep" The inverter did not alarm at the 11.1 but would have at 11 but still run until shut off at 10 something. Both times cost about 7AH each
C. Another example kettle and furnace on 107AH and now 90.1 amp draw voltage 10.9 and inverter beeping
So that time 90/107 is an 84% draw.
I first got one SiO2 to run the MW (700w RCA) in the TC and did a quick test where ISTR it ran its 55 amp draw for over 30 minutes till SOC was about 20% afterwards. The battery discharge tables in their specs showed the discharge time was close to specs for that size draw.
The comical thing is I learned the MW can heat the water enough to make my coffee using fewer AH than the kettle in the TC.
-kettle 5 minutes at 89 amps --voltage drop 1.0 volt
-MW 3 minutes at 55 amps (MSW inverter. A PSW inverter would draw more amps but not take as long to heat the water, but still use more AH than the MSW depending on your version of hot enough)--voltage drop 0.8 volt.
Note the kettle also needs more water than needed for a cup to reach its minimum fill level marker, and it gets the water too hot. Yes I can use the propane stove with a pot of water and do it that way--if desperate!
However that is in the TC with the small MW and MSW. In the MH the MW is bigger and the inverter is PSW, so the kettle is a valid choice.
So that was pretty good IMO. For those kinds of high draws I would need four 6s at 50% SOC or 90/230 = 39% draw to stay above inverter alarm at 11 volts
Here is some info on them --I am not selling them!!! Just trying to show what they are
https://azimuthsolar.ca/product/12v-100ah-sio2-battery/
One big thing they are supposed to be good for is high amp draw loads for their size in AH. So here is what I found on that:
1. The 200AH bank (two 100s) with the 2000w MSW inverter and my wiring job has a voltage drop that stays about the same for the same load at any SOC above inverter shut-off voltage.
2. The MW draws about 55 amps and the kettle draws about 89 amps and the furnace in the TC draws about 3.5 amps.
So example using kettle to boil water for cup of instant coffee. (No advice needed on making coffee, you latte bunch, thanks anyway :) )
A. Monitor before start--142AH, 12.7 volts, 71% SOC
After start- 88.7 amps draw, 11.7 volts, about five minutes kettle off
Monitor now--135AH, 12.5 volts (rising slowly), 68%
So that time 89/142 is a 63% draw.
B. Before-- 113AH, 12.3 volts, 57%
-11.5v at 88a
-11.2v at 90.5a
-11.1v at 90.6a
After= 106AH, 53% SOC
So that time 90/110 is an 82% draw.
(note how inverter amps go up as voltage goes down--"inverter creep" The inverter did not alarm at the 11.1 but would have at 11 but still run until shut off at 10 something. Both times cost about 7AH each
C. Another example kettle and furnace on 107AH and now 90.1 amp draw voltage 10.9 and inverter beeping
So that time 90/107 is an 84% draw.
I first got one SiO2 to run the MW (700w RCA) in the TC and did a quick test where ISTR it ran its 55 amp draw for over 30 minutes till SOC was about 20% afterwards. The battery discharge tables in their specs showed the discharge time was close to specs for that size draw.
The comical thing is I learned the MW can heat the water enough to make my coffee using fewer AH than the kettle in the TC.
-kettle 5 minutes at 89 amps --voltage drop 1.0 volt
-MW 3 minutes at 55 amps (MSW inverter. A PSW inverter would draw more amps but not take as long to heat the water, but still use more AH than the MSW depending on your version of hot enough)--voltage drop 0.8 volt.
Note the kettle also needs more water than needed for a cup to reach its minimum fill level marker, and it gets the water too hot. Yes I can use the propane stove with a pot of water and do it that way--if desperate!
However that is in the TC with the small MW and MSW. In the MH the MW is bigger and the inverter is PSW, so the kettle is a valid choice.
So that was pretty good IMO. For those kinds of high draws I would need four 6s at 50% SOC or 90/230 = 39% draw to stay above inverter alarm at 11 volts
