Stupid battery and solar questions
I figure I am going to have a lot of them, so I better put all in one thread :B. My situation: - I mainly want solar for running residential freezer and fridge, maybe also for charging my shave ...
Forum Discussion
Do take note that battery temperature and ambient temperature can be quite different, especially when higher amps are used to get the battery to absorption voltage.
My AGM right now reads 85.6 degrees with the sensor on the middle of the side of the battery case. It is being held at 14.3v and is accepting 3.8 amps.
Ambient temp is 74F and was 64F at daybreak. i had taken 53Ah from it overnight, and fed it 40 meanwell amps at 10:30. It was 71F at 10:30am before 40 amps were applied. Now it is 85.6f and not really increasing any more. Battery monitor is wrong stating 2Ah from full. It will get rezeroed tonight after sundown.
Much of my previous charging was justing using ambient temps as a voltage baseline, and actual data reveals my battery was significantly hotter than ambients, and my chosen voltage, higher than it needed to be.
This is one of the AGMS with no upper limit on charging amps. it should heat up less than other AGMS whose max initial current is limited to 30%.
This battery is also under the vehicle. I assumed it would not get as hot as in the engine compartment, but the temperature sensor revealed this assumption to be false as well, the battery is still bathed in engine heat. If it stays cooler than it would in the actual engine copmpartment is something I do not have data on, as I have no battery in there at the moment and no plans to add one.
The temperature sensor on the battery case has been quite an eye opener for me.
Not too much I could do about charging voltage before I got the Meanwell RSP-500-15 or added an adjustable voltage regulator on my alternator with voltage potentiometer on dashboard. My solar controller is programmable, but does not have the option for a battery temp sensor so it too was likely seeking a absorption voltage at 77F, when the battery was often likely much hotter than that.
For all my previous imprecision regarding Absorption voltage and actual battery temperature, this current AGM battery is still performing splendidly, in my opinion, having watched the trends and tendencies closely of many batteries throughout their cycle lives with an AH counter.
Voltage held under load is impressive. With 45Ah removed of 90 total available AH when new, voltage when loads are removed quickly rebounds to above 12.2. It will be 3 years old in November and has about 350 deep cycles on it today with a couple hundred more shallow cycles on it, and a couple thousand engine starts.
Performance wise, it is spanking the screwy31, and has destroyed no clothing. I think I am an AGM convert, but will stick with the AGMS that openly state they have no upper limits on charging amps like Odyssey, lifeline and Northstar.
Any battery I use has to be able to shrug at 40 to 60 amps charge current, and much more briefly when alternator and wiring are still cold. This is at odds with the low and slow solar as such batteries seem to require higher currents when deeply cycled, but all 3 sources have kept this battery well into the impressive zone.
If I did not have high amp charging sources available, low and slow solar only, I would use flooded batteries only
My AGM right now reads 85.6 degrees with the sensor on the middle of the side of the battery case. It is being held at 14.3v and is accepting 3.8 amps.
Ambient temp is 74F and was 64F at daybreak. i had taken 53Ah from it overnight, and fed it 40 meanwell amps at 10:30. It was 71F at 10:30am before 40 amps were applied. Now it is 85.6f and not really increasing any more. Battery monitor is wrong stating 2Ah from full. It will get rezeroed tonight after sundown.
Much of my previous charging was justing using ambient temps as a voltage baseline, and actual data reveals my battery was significantly hotter than ambients, and my chosen voltage, higher than it needed to be.
This is one of the AGMS with no upper limit on charging amps. it should heat up less than other AGMS whose max initial current is limited to 30%.
This battery is also under the vehicle. I assumed it would not get as hot as in the engine compartment, but the temperature sensor revealed this assumption to be false as well, the battery is still bathed in engine heat. If it stays cooler than it would in the actual engine copmpartment is something I do not have data on, as I have no battery in there at the moment and no plans to add one.
The temperature sensor on the battery case has been quite an eye opener for me.
Not too much I could do about charging voltage before I got the Meanwell RSP-500-15 or added an adjustable voltage regulator on my alternator with voltage potentiometer on dashboard. My solar controller is programmable, but does not have the option for a battery temp sensor so it too was likely seeking a absorption voltage at 77F, when the battery was often likely much hotter than that.
For all my previous imprecision regarding Absorption voltage and actual battery temperature, this current AGM battery is still performing splendidly, in my opinion, having watched the trends and tendencies closely of many batteries throughout their cycle lives with an AH counter.
Voltage held under load is impressive. With 45Ah removed of 90 total available AH when new, voltage when loads are removed quickly rebounds to above 12.2. It will be 3 years old in November and has about 350 deep cycles on it today with a couple hundred more shallow cycles on it, and a couple thousand engine starts.
Performance wise, it is spanking the screwy31, and has destroyed no clothing. I think I am an AGM convert, but will stick with the AGMS that openly state they have no upper limits on charging amps like Odyssey, lifeline and Northstar.
Any battery I use has to be able to shrug at 40 to 60 amps charge current, and much more briefly when alternator and wiring are still cold. This is at odds with the low and slow solar as such batteries seem to require higher currents when deeply cycled, but all 3 sources have kept this battery well into the impressive zone.
If I did not have high amp charging sources available, low and slow solar only, I would use flooded batteries only
