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Discussion Starter · #1 ·
Did a search, didn't find what I was looking for. I am picking up 8 modules that are 44v each, to run in series. The car isn't ready for them yet, so they will sit on the bench. What is everyone doing to keep them charged and ballenced while they wait to go into to car? I plan on playing with the Orion BMS while they sit, so I'll need to figure all that out as well.

Thanks in advance for opinions and advice for this setup.
 

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Did a search, didn't find what I was looking for. I am picking up 8 modules that are 44v each, to run in series. The car isn't ready for them yet, so they will sit on the bench. What is everyone doing to keep them charged and ballenced while they wait to go into to car? I plan on playing with the Orion BMS while they sit, so I'll need to figure all that out as well.

Thanks in advance for opinions and advice for this setup.
Are they Lithium Ion? Missing quite a bit of information to give good advice but generally with Lithium Ion you darin them or charge them to 50% capacity and store them this way. Internal capacity fade is very small and they can sit for a very long time with no maintenance. However, I would suggest you look and see who the manufacturer of the cells are and follow their recommendations.
 

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Sorry for the lack of information. They are LG Chem Lithium. Basically the same as the 60.8V ones, just 12 in series instead of the 16 in series.

They come with the stock BMS boards on the sides of them, I'll need to figure out if I take those off to use the Orion, or just plug the Orion into them.
 

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Sorry for the lack of information. They are LG Chem Lithium. Basically the same as the 60.8V ones, just 12 in series instead of the 16 in series.

They come with the stock BMS boards on the sides of them, I'll need to figure out if I take those off to use the Orion, or just plug the Orion into them.
I couldn't find the specifications on these cells contact evwest looks like they sell them
 

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Hey, I bought my cells back in February of last year, They started out at 26.4 volts, they are now down to about 26.28v. They are Tesla modules with 18650 cells. The BMS boards are all going to be proprietary, and I am not sure that they will really be of any use - although I have not really dug into what people are working on as far as hacking that sort of thing. Its way over my head, at any rate. I did have one module that dropped about a quarter of a volt relative to the other ones, and I think it might have been that BMS board. After I unplugged them, they stopped diverging. I would suggest you do the same.

Each BMS board will have a wiring harness that connects to each cell, and possibly to some thermistors as well. You will probably want to find the mating harness on digikey, and that is what your Orion BMS will connect to.

As long as there is no load on the cells, they should stay pretty well balanced. I think you could easily go a year or two without worrying about them. I did have problems with my BMS tap wires corroding, but this might just have been a fluke. If at all possible, I would try and store the batteries somewhere clean and dry without big temperature and humidity fluctuations, though.
 

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Hey, I bought my cells back in February of last year, They started out at 26.4 volts, they are now down to about 26.28v. They are Tesla modules with 18650 cells. The BMS boards are all going to be proprietary, and I am not sure that they will really be of any use - although I have not really dug into what people are working on as far as hacking that sort of thing. Its way over my head, at any rate. I did have one module that dropped about a quarter of a volt relative to the other ones, and I think it might have been that BMS board. After I unplugged them, they stopped diverging. I would suggest you do the same.

Each BMS board will have a wiring harness that connects to each cell, and possibly to some thermistors as well. You will probably want to find the mating harness on digikey, and that is what your Orion BMS will connect to.

As long as there is no load on the cells, they should stay pretty well balanced. I think you could easily go a year or two without worrying about them. I did have problems with my BMS tap wires corroding, but this might just have been a fluke. If at all possible, I would try and store the batteries somewhere clean and dry without big temperature and humidity fluctuations, though.
That is good useful nformation. I would like to note one thing. Lithium batteries don't drop much voltage over time but they capacity will fade. I had some I stored a year and they were all close to the same voltage, they were LiFePO4 cells so they were all around 3.3 volts, however when I discharged them they only had about 45Ah in a 100 Ah cell. Not to worry though, I cycled them three times and the third time I got 100Ah.
 
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