Hello all. We have been living off grid for about 2 years now. We have a 12 volt system because the only thing plugged i that we use is a car fridge. So we have 2 280 watt panels. That go into a 40 amp CC. We use 4 210 6 volt batteries. We have had this for the 2 years. About a month ago we had a baby and decided to get new battery's and get a mini fridge. So we got 4 230 6 volt batteries and a 30 watt freezer. Here's the issue. Everything's plugged in normal. We unhooked everything so only solar was at batteries. The CC will read batteries at 100% then they start dropping when sun goes down with nothing plugged in. I even unhooked 2 batteries so it was just the 2 6 volts and it does the same. Any ideas why batteries aren't staying charged?
Battery set up help
- Thread starter Dwd902
- Start date
This has likely always happened, and you just never noticed it.
Almost a certainty that they are staying charged. The CC is probably reporting SoC based purely on voltage, which is a horrible way to report SoC. Once you stop charging a battery, it's voltage will drop.
You can confirm this by reporting the actual voltage of the battery bank.
If you actually want to know the state of charge of your batteries, you need a battery monitor:
Congrats on the new baby. I don't know how that played into a decision to marginally increase your battery bank. Your usage dictates how much battery and how much panel you need. Given your prior loads, I would be surprised if you needed new batteries to power the new items.
What did you do with the old batteries?
Are all batteries flooded lead acid? Do you properly maintain them?
Almost a certainty that they are staying charged. The CC is probably reporting SoC based purely on voltage, which is a horrible way to report SoC. Once you stop charging a battery, it's voltage will drop.
You can confirm this by reporting the actual voltage of the battery bank.
If you actually want to know the state of charge of your batteries, you need a battery monitor:
Off-grid Solar Battery Monitors
Building a vehicle mounted solar power system? Let me help.
www.mobile-solarpower.com
Congrats on the new baby. I don't know how that played into a decision to marginally increase your battery bank. Your usage dictates how much battery and how much panel you need. Given your prior loads, I would be surprised if you needed new batteries to power the new items.
What did you do with the old batteries?
Are all batteries flooded lead acid? Do you properly maintain them?
Sorry I wasn't very clear. Its 4 new batteries the old batteries are at a different location. We just got 4 new for less stress in case something happens due to breastmilk storage. They are properly maintained and lead acid. I will purchase a battery monitor and see if that changes anything. Thank youThis has likely always happened, and you just never noticed it.
Almost a certainty that they are staying charged. The CC is probably reporting SoC based purely on voltage, which is a horrible way to report SoC. Once you stop charging a battery, it's voltage will drop.
You can confirm this by reporting the actual voltage of the battery bank.
If you actually want to know the state of charge of your batteries, you need a battery monitor:
Off-grid Solar Battery Monitors
Building a vehicle mounted solar power system? Let me help.www.mobile-solarpower.com
Congrats on the new baby. I don't know how that played into a decision to marginally increase your battery bank. Your usage dictates how much battery and how much panel you need. Given your prior loads, I would be surprised if you needed new batteries to power the new items.
What did you do with the old batteries?
Are all batteries flooded lead acid? Do you properly maintain them?
Gotcha. The battery monitor works by counting the current that goes through it and then compares that to the amount you programmed in. A % SoC is reported on that basis.
Lastly, unless your batteries are in a temperature controlled environment, you need temperature compensation during charge.
Lastly, unless your batteries are in a temperature controlled environment, you need temperature compensation during charge.
