Whst kind of batteries?

[pengyou]

what kind of batteries do you have in your solar energy systems? If lithium ion, are they based on 18650 cells or prismatic?

[EastCoastCB]

https://www.google.com/search?q=sola...ch=skoolie.net

[Doktari]

I have Nissan Leaf Lithium ion batteries which are not 18650 and not prismatic. They are pouch cells in a big metal case. They are better voltage for 48 volt inverter than for 24 or 12 volt inverter. Need to be kept in temperature conditioned space also. Do not charge while near freezing and never below freezing. Of course like all Lithium chemistries do not overcharge.

[PNW_Steve]

Flooded lead acid.

Take a look at the batteries section over at solarpaneltalk. There are some great stickies regarding battery selection and maintenance.

https://www.solarpaneltalk.com/forum...energy-storage

[Johnny Mullet]

I am using (2) 6 volt golf cart batteries wired in series for 12V and 235 amp hours. No issues at all.

[Doktari]

You’ll get a lot of opinions regarding batteries. I hope your ready for a lot of reading. The solarpaneltalk website does have a lot of good information. Batteryuniversity.com has loads of information also. If solar and short buses weren’t my main hobby currently I’d consider downsizing to a single Northstar AGM battery in a van. I was inspired by a thread where someone used one for 5 years even with a small fridge. Ventilation fans, lights, and other small loads. He took it out for capacity testing and it still could handle 70 amps for a while, an hour I think. He tried to kill it but it wouldn’t die so he put it back in. I dont remember for exactly how long. This was near SanDiego in a relatively stable temperature which helps for testing.
My old house batteries besides the Nissan Leaf batteries I’m hoping to try are gel and small agm UPS which are at outside ambient temperature in a much cooler climate than San Diego coastal climate so they are sluggish during the Winter when the power is needed. They get voltage sag when cold. So I baby them. Considering building a insulated battery box but I have grid power currently and am waiting until I find a good off grid location. Temp compensated charging is important for the health of the batteries when they are exposed to temperature swings. I read temp compensation for Lithium is about half that of lead acid and can be ignored especially as they should be placed in a frost proof container anyway.
I believe Northstar agm is comparable to Optima agm but much more selection with Northstar. They cost a premium. The person who tested one also improved his van charging system with voltage adjustment and temperature sensor on the alternator.
I hauled 400 lbs of lead agm ups batteries in my cargo trailer for two years. I eventually got tired of pulling the extra weight. It did put them to good use. If all goes well the new setup with the Leaf Lithium batteries will be half the weight and four times the capacity of the agm batteries in the cargo trailer. In a big bus the weight isn’t so much of a concern. I’m pulling the cargo trailer with a short bus and a 350 V8 gasser. If I had a big bus I’d still consider FLA L16 or golf cart batteries.
Now I’m considering putting the Nissan Leaf batteries in a neighborhood electric vehicle someone gave me and limping along on my old lead acid batteries a while longer. So as you see there’s lots of circumstances involved.
It’s looking like the debate over LFP or NMC batteries is ongoing but NMC is gaining credibility and acceptance with each new generation. It’s still early but the range and capacity of the 2019 NMC is much higher than previous. Comparable to LFP. I’m hoping my generation NMC 2 Leaf modules will power this NEV adequately or beyond my wildest dreams for solar. Knock on wood....
I keep hearing about other batteries over the years then nothing. Nada. There are better batteries. But they cost a fortune or are made from unobtainium. Or they weigh a massive amount.

[pengyou]

Thanks! So my guess is that most people are using some variation of lead-acid batteries. There are some good reasons to do so. Even though they cost more, I am looking at lithium-xxx because they take up less space and they weigh much less - not so concerned about the weight on the bus but the weight on my body to move them. The pouch batteries, as you put it (I have heard people call them prismatic, maybe a brand name carry over?? are lighter than the 18650 cells but usually need more protection. I will read some more. Thanks for the directions!

[brokedown]

Lithium is great as long as you have a good quality battery management system. If you allow them to run out of spec, they won't last very long at all. I went with AGM and I'm about 3 years into ownership of them. The only times I'm upset about them is when I have to lift them. When these expire and need to be replaced I will likely go with pairs of 6v batteries.