03-14-2019, 03:53 PM
I like the idea of total lifetime amp hours rating, or better yet lifetime KWH in terms of expected battery life, instead of cycles which can be so vague.
while many AGMs are heavier and come in at a lower AH rating for the same size battery, if one were to rate them in KWH, since they usually maintain higher voltage under discharge, they would likely come out ahead on the total capacity rating, but in AH only, it artificially makes the flooded battery appear to have higher capacity for less$$ and less weight when the AGM, if properly recharged would have been able to power more for longer anda larger lifetime AH/WH
Also the 50% rule with lead acid gets smeared out of place, with people thinking that if they go below 50% then the battery is doomed, but in relity as long as it is not brought down o 20% and left there for days on end, the total lifetime KWH is likely the same as if one observed the 50% rule.
i've got hundreds of cycles well below 50% on my AGM but proper and full recharges are done often. Its lifetime KHW is no doubt impressive so far, but I could only roughtly guestimate the amount if i were to put the thought into it and run some numbers, hich I will not bother with.
If Lifepo4 are really finicky about living fully charged, perhaps lower the absorption voltage or take a panel or two off line after sundown when sunny skies are expected the next day, Whether taking panes offline in direct sun when making lots of amps is detrimental to panels, well it is a possibility, and one I avoid and recommend be avoided when possible.
One reason i have not pursued lithium is one supposedly has to unlearn the get it full asap keep it full for best service life of lead acid mentality. i guess the only time you really need to fully charge lithium is when you need their full capacity for that next discharge.
Looks like someone could heat a good amount of water electrically with their excess solar and keep the lithium from sitting full all afternoon.
while many AGMs are heavier and come in at a lower AH rating for the same size battery, if one were to rate them in KWH, since they usually maintain higher voltage under discharge, they would likely come out ahead on the total capacity rating, but in AH only, it artificially makes the flooded battery appear to have higher capacity for less$$ and less weight when the AGM, if properly recharged would have been able to power more for longer anda larger lifetime AH/WH
Also the 50% rule with lead acid gets smeared out of place, with people thinking that if they go below 50% then the battery is doomed, but in relity as long as it is not brought down o 20% and left there for days on end, the total lifetime KWH is likely the same as if one observed the 50% rule.
i've got hundreds of cycles well below 50% on my AGM but proper and full recharges are done often. Its lifetime KHW is no doubt impressive so far, but I could only roughtly guestimate the amount if i were to put the thought into it and run some numbers, hich I will not bother with.
If Lifepo4 are really finicky about living fully charged, perhaps lower the absorption voltage or take a panel or two off line after sundown when sunny skies are expected the next day, Whether taking panes offline in direct sun when making lots of amps is detrimental to panels, well it is a possibility, and one I avoid and recommend be avoided when possible.
One reason i have not pursued lithium is one supposedly has to unlearn the get it full asap keep it full for best service life of lead acid mentality. i guess the only time you really need to fully charge lithium is when you need their full capacity for that next discharge.
Looks like someone could heat a good amount of water electrically with their excess solar and keep the lithium from sitting full all afternoon.
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