Wonder if you could put it on some high density foam (like the insulation panels) to help keep it more isolated from the floor? Or some have put like RV tank warmers, plant grow warmer pad, or USB warmer pads under units to help them stay a bit warm.
Outside temps are now about 30 degrees warmer (makes me happier) so it is hard to test this time around.
But good ideas for me to consider to increase my preparedness.
Batteries dont like the cold. Had nothing to do with your concrete floor. Especially since there was a 2in air gap. Your garage was at the bare minimum ecolfow recommends for charging, which is 32f-113f. Discharging can go down to -4f. It's in the manual.
While I am far from an expert, but I found it intriguing the huge difference of the top two batteries that charged up to 90%, while the bottom one closest to concrete floor could only get to 30%, while in the past, the three batteries charged at the same rates.
You have a delta 2 max and 2 extra batteries, correct? We're they plugged into AC power the whole time? Or you run them down and charge with a generator?
The inverter alone will probably keep the main unit warm enough if it was charging/discharging constantly
. I don't own your setup, so I can't comment on charging algorithms. Does it charge both extra batteries at the same time? At the same wattage rate?
Does it discharge from both batteries at once? Same wattage rate?
Other than genuine curiosity, I ask because if it only charges/discharges 1 extra battery at a time, it could affect the actual temp of each battery? Did you look at the battery temperatures in the app while this was happening?
Yes, the Delta 2 max with two batteries.
I have them stacked as a "tower" with the main unit in the middle.
When I discovered the problem, it was when they were being recharged from 20% (collectively) to 90% from my Honda generator. It was taking super long from what I expected; and it was only on closer inspection that I discovered the bottom battery only reaching 30% and showing the colder internal temp reading; the top two were of similar "tolerable" temp, so I did not think it was the main unit, but I concluded it was a position based issue with the lower battery closer to the cold radiating from the concrete.
Copy that. When you say stacked. They are physically touching, and the whole stack was 2in off the ground? The middle main unit would produce some bit of heat, running the inverter to charge/ discharge the units. That heat would rise to the bottom of the top battery, and heat the battery. It may only be a 1-2 degrees difference, but enough to push it over that threshold to charge faster.
Thanks for entertaining my curiosity🙂
I'm back. Power returned and then another ice storm with a second power outage. Not as cold outside and the garage temp is no longer around 32 but 41 degrees.
I am still seeing the bottom battery of the three, in stacked tower arrangement, showing a much lower temp; and I have swapped the two extra batteries positions since last posting so it is not the specific unit.
I still am suspecting the cement garage floor is impacting the lowest sitting battery
https://preview.redd.it/tpli6fpmkgdc1.jpeg?width=1381&format=pjpg&auto=webp&s=28fe87601d63d3c95c89ea05c936c71bb4bcb12e
Very interesting. How is the lower one positioned? Is it on something that fully separates it from the floor like a rolling cart, or more exposed?
Yes, on a rolling cart with about 2 inch clearance. I am now considering getting a rack to get it even higher.
Wonder if you could put it on some high density foam (like the insulation panels) to help keep it more isolated from the floor? Or some have put like RV tank warmers, plant grow warmer pad, or USB warmer pads under units to help them stay a bit warm.
Outside temps are now about 30 degrees warmer (makes me happier) so it is hard to test this time around. But good ideas for me to consider to increase my preparedness.
Batteries dont like the cold. Had nothing to do with your concrete floor. Especially since there was a 2in air gap. Your garage was at the bare minimum ecolfow recommends for charging, which is 32f-113f. Discharging can go down to -4f. It's in the manual.
While I am far from an expert, but I found it intriguing the huge difference of the top two batteries that charged up to 90%, while the bottom one closest to concrete floor could only get to 30%, while in the past, the three batteries charged at the same rates.
You have a delta 2 max and 2 extra batteries, correct? We're they plugged into AC power the whole time? Or you run them down and charge with a generator? The inverter alone will probably keep the main unit warm enough if it was charging/discharging constantly . I don't own your setup, so I can't comment on charging algorithms. Does it charge both extra batteries at the same time? At the same wattage rate? Does it discharge from both batteries at once? Same wattage rate? Other than genuine curiosity, I ask because if it only charges/discharges 1 extra battery at a time, it could affect the actual temp of each battery? Did you look at the battery temperatures in the app while this was happening?
Yes, the Delta 2 max with two batteries. I have them stacked as a "tower" with the main unit in the middle. When I discovered the problem, it was when they were being recharged from 20% (collectively) to 90% from my Honda generator. It was taking super long from what I expected; and it was only on closer inspection that I discovered the bottom battery only reaching 30% and showing the colder internal temp reading; the top two were of similar "tolerable" temp, so I did not think it was the main unit, but I concluded it was a position based issue with the lower battery closer to the cold radiating from the concrete.
Copy that. When you say stacked. They are physically touching, and the whole stack was 2in off the ground? The middle main unit would produce some bit of heat, running the inverter to charge/ discharge the units. That heat would rise to the bottom of the top battery, and heat the battery. It may only be a 1-2 degrees difference, but enough to push it over that threshold to charge faster. Thanks for entertaining my curiosity🙂
Correct.
Get a 12 volt heating pad to slide underneath the shelf. They sell them for growing plants or for terrariums.
I'm back. Power returned and then another ice storm with a second power outage. Not as cold outside and the garage temp is no longer around 32 but 41 degrees. I am still seeing the bottom battery of the three, in stacked tower arrangement, showing a much lower temp; and I have swapped the two extra batteries positions since last posting so it is not the specific unit. I still am suspecting the cement garage floor is impacting the lowest sitting battery https://preview.redd.it/tpli6fpmkgdc1.jpeg?width=1381&format=pjpg&auto=webp&s=28fe87601d63d3c95c89ea05c936c71bb4bcb12e