Yes, you may want to add temperature control to your BMS requirement. Or even some kind of AC or DC heating element. Of course plenty of insulation in your battery enclosure.Should I get something that prevents the batteries from being charged when temps are too low or too high? Are most charge controllers able to be adjusted to not allow the batteries to be discharged past a certain limit and to prevent charging above some limit.
Why are you using that instead of LiFePO4?If I use Nissan Leaf modules to build a 48V battery what sensors and controls will it require?
If I use Nissan Leaf modules to build a 48V battery......
Initially, I did not see the OP question as prospective. If he still has a choice I would recommend using LFP which can be purchased new for less than used Leaf modules. Then he can safely put them in the cabin.Why are you using that instead of LiFePO4?
Cost.Why are you using that instead of LiFePO4?
Cost.
If he still has a choice I would recommend using LFP which can be purchased new for less than used Leaf modules.
With some silly zoning issues I'm allowed to use an external generator but I may not have a permanent solar system. My array will be quickly removable and all my equipment and batteries will be in a very small trailer that is mobil. The cabin will be "fed" through a generator cable to and from proper generator receptacles and plugs (240v30a). The regulation does not prohibit solar generators so my system will be mobil and I will not be forced to use a stinky noisy generator when I can use clean quiet solar.Initially, I did not see the OP question as prospective. If he still has a choice I would recommend using LFP which can be purchased new for less than used Leaf modules. Then he can safely put them in the cabin.
Cost.
What does that 80% refer to? I see these percentages in the ads and know that it has something to do with being used up but what is used up, the number of cycles usefully left in the batteries or the voltage or wattage or amperage...? I can't associate the word capacity to anything meaningful to me. I've seen many G1 Leaf packs rated 60% and G2 Leaf packs rated at 70%. My math says that 6/7=86 which means that 60 is 14% less than 70, but the prices were 1800 and 2500 and 18/25=72 so the 1800 is 28% less than 2500. I would expect the capacity difference to correlate with the price difference but it doesn't.I think in Watt hours. In 2016 I bought a Nissan Leaf pack for $1500 so $1800 is not a bad deal. The capacity was only 80% so in your case that is still a good price of $100 per kWh.
Also, the higher the voltage of the battery the proportionately less a reduction in ah results in a loss of kWh? I used to be very good at math but that was a very long time ago and I'm "rusty".Would I be understanding correctly that because watts=volts x amps that a reduction of ah would not be one to one when looking at kWh but a loss in the same direction?
Just do the math.Would I be understanding correctly that because watts=volts x amps that a reduction of ah would not be one to one when looking at kWh but a loss in the same direction?
I was referring to 80% of capacity. Depending on how you want to measure it Amphours or Watthours. It is hard to know how many cycles are left. When buying a pack it is hard to do a test unless the seller lets you take the lid off. Even then only measuring internal resistance is the only rest that can be done quickly. A full charge/discharge would take hours and need access to power.What does that 80% refer to?
I just bothered to read the power bio under your post and you might not know everything but I'd guess you know enough. So then I went back and re-read all your posts above, feeling stupider and stupider as I went. The conclusion I've come to is that the biggest piece of work that I have left to do is to come up with the right questions; I'm pretty sure you've got the answers and I just need to know how to ask what I want to know. As you are beginning to use LFP's and you've been using Leaf modules can I assume that both can be good ways to go, especially for a rather small system? Am I correct that used Leaf batteries are significantly cheaper than new LFP's. Cheap is doubly important to me because it's part of my nature and because I'm retired on a rather tight budget. I have a very tiny cabin in the woods which I would like to be slightly civilized. I have a composting toilet, a very large water tank, and abundant sunshine. I also have a nasty bureaucracy to deal with (mentioned above). I could probably make do 3/4 of the year with a quiet little inverter generator but I would not enjoy that much. I would like to have a water line from my tank to the cabin with an on/off switch on the pump. I would also need heat tapes to protect the water tank and the line to the cabin and the lines in the cabin With that I will keep a small cistern in the loft full the water that will just be for washing dishes, cooking and brushing teeth etc. I'd like to power a cellular based security system. I'll have wood heat and electric for A/C, the smallest 115v mini-split. I will probably watch tv, listen to the radio and browse the internet via laptop. I know nothing about some of the things I've heard about such as using a phone for a wifi hotspot. When 5G comes in around here perhaps I'll be able to stream movies. That sounds perfect to me and I hope that is doable. I'll require some outlets both indoors and out so that I can run something like a saw or compressor once in a while.I was referring to 80% of capacity. Depending on how you want to measure it Amphours or Watthours. It is hard to know how many cycles are left. When buying a pack it is hard to do a test unless the seller lets you take the lid off. Even then only measuring internal resistance is the only rest that can be done quickly. A full charge/discharge would take hours and need access to power.