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 s...
Forum Discussion
IMO you don't need "hands on experience", but you do need some ability to "critical read". PT can do that same as the rest of us.
So far my experience with SiO2 shows they do the depth of discharge as claimed, but I have not confirmed much of the other data claims.
You have to distinguish between data sheet stuff and dealer sales claims, which we all are able to do too.
Looking at Azimuth dealer claims trying to sell SiO2s, eg they push the cold weather operating range as -40C.
But Stark brand AGMs also claim -40C to 60C operating range, so what is so special about SiO2 in the cold? Beats me. Would have to do more research if I cared.
http://www.wegosolar.com/products.php?product=SKR%252d125AGM-Stark-AGM-12V-Solar-Battery-Sealed-125A
Speaking of "sales" note that is really a 105AH batt at the 20 hr rate. Another trick is if they use the 10 hr rate like ISTR SiO2 does in some blurbs. Got to pay attention!
Claim is "faster charging" with SiO2. That is where I always want to see the actual charging profiles with times etc for a side by side comparison.
Usually you see that faster charging has to do with a lower internal resistance. Maybe. Sometimes they mean you can use a higher amp charging rate and that makes for less time. But if you use the same 55 amp charger it will do 55 amps and no more in each case.
So the SiO2 spec says IR is "under 6.8 mOhms". The Stark AGM says 5 mOhms. So how can the SiO2 be faster? But these IRs are at 77F. We don't know the IRs at different charging rates and where along in SOC the IRs are. Makes you wonder how the SiO2 could be "faster"
They both have charging limits of about 27% so you can't use a bigger amp charger to get a faster time like you could with LFP, eg.
So here is their claim for "faster charging"
https://azimuthsolar.ca/wp-content/uploads/2019/11/Azimuth-Silicon-Dioxide-4-Pager-min-1.pdf
2 x faster! 3 hrs vs 6 hrs . So how far down in SOC is the starting point where you can charge it up to what SOC ? "Regular" 100AH batts take a very long time to get from 90 to 100% SOC. On generator (their sales pitch for less gen time) you stop the charge at 90 anyway. So what is the comparison in time for doing 50-90s?
Seems like a bogus sales claim to me! It could turn on where along in SOC it goes from constant amps to tapering amps. That is why we need the charging profiles to compare them.
Anyway, I will check for that with my SiO2s and see how it goes.
I do think the data sheet stuff can be believed but you have to watch out for those "sales" guys. :( (and that is just as true for LFP ads on "faster charging" with no side by side charging profiles)
So far my experience with SiO2 shows they do the depth of discharge as claimed, but I have not confirmed much of the other data claims.
You have to distinguish between data sheet stuff and dealer sales claims, which we all are able to do too.
Looking at Azimuth dealer claims trying to sell SiO2s, eg they push the cold weather operating range as -40C.
But Stark brand AGMs also claim -40C to 60C operating range, so what is so special about SiO2 in the cold? Beats me. Would have to do more research if I cared.
http://www.wegosolar.com/products.php?product=SKR%252d125AGM-Stark-AGM-12V-Solar-Battery-Sealed-125A
Speaking of "sales" note that is really a 105AH batt at the 20 hr rate. Another trick is if they use the 10 hr rate like ISTR SiO2 does in some blurbs. Got to pay attention!
Claim is "faster charging" with SiO2. That is where I always want to see the actual charging profiles with times etc for a side by side comparison.
Usually you see that faster charging has to do with a lower internal resistance. Maybe. Sometimes they mean you can use a higher amp charging rate and that makes for less time. But if you use the same 55 amp charger it will do 55 amps and no more in each case.
So the SiO2 spec says IR is "under 6.8 mOhms". The Stark AGM says 5 mOhms. So how can the SiO2 be faster? But these IRs are at 77F. We don't know the IRs at different charging rates and where along in SOC the IRs are. Makes you wonder how the SiO2 could be "faster"
They both have charging limits of about 27% so you can't use a bigger amp charger to get a faster time like you could with LFP, eg.
So here is their claim for "faster charging"
https://azimuthsolar.ca/wp-content/uploads/2019/11/Azimuth-Silicon-Dioxide-4-Pager-min-1.pdf
2 x faster! 3 hrs vs 6 hrs . So how far down in SOC is the starting point where you can charge it up to what SOC ? "Regular" 100AH batts take a very long time to get from 90 to 100% SOC. On generator (their sales pitch for less gen time) you stop the charge at 90 anyway. So what is the comparison in time for doing 50-90s?
Seems like a bogus sales claim to me! It could turn on where along in SOC it goes from constant amps to tapering amps. That is why we need the charging profiles to compare them.
Anyway, I will check for that with my SiO2s and see how it goes.
I do think the data sheet stuff can be believed but you have to watch out for those "sales" guys. :( (and that is just as true for LFP ads on "faster charging" with no side by side charging profiles)
