Ok great and would this one work or is there one that you recommend?
https://www.amazon.com/dp/B09W9T8D2...L9HMAP20K&ref_=list_c_wl_lv_ov_lig_dp_it&th=1
I have got it all figured out and I think I will be building a wooden enclosure for it instead of using the metal one it came with.
I built up my battery bank from Chevy Bolt battery modules. The process is a bit different, but does share a lot of the same issues. One big difference, the Bolt cells are pouch style with tabs spot welded to the bus bars.
Building your battery into 4 separate 3P7S batteries will give you some options later. For "24 volts" you run the 4 batteries in parallel and they will share the current. But I think the BMS you linked is a bit light. 40 amps each x 4 is 160 amps total. At 24 volts, that is almost 4,000 watts, so it might be enough, but only if the 4 batteries share the load current equally. The cells can take more current, so I would go with a higher current BMS to be on the safe side, and also reduce the series resistance. The other issue is the BMS you linked is a split port type. IF all of your charging is from a DC charge controller, and all of your loads are separate from any charging source, it can work, but most here use a common port BMS and the charge and discharge both flow through the same port. The charge rate on that separate port is only 10 amps also. Even with 4 in parallel, that is a maximum of 40 amps of charge current, or under 1,000 watts of charge power on a 24 volt system.
Here is the 100 amp common port "Smart" version with Blue Tooth.
I am using a pair of the dumb version, no blue tooth. They have been working just fine for nearly 2 years now. I miss the cell monitoring, and wish I had gotten the smarter version. My other bank is using a JK-BMS with a 200 amp rating, blue tooth monitoring, and 2 amps of active balancing. It's a great part, but you do pay for it, to about $300 now for the 200 amp up to 24S unit I have. Many "Smart" BMS units can be programmed for a range of cell counts and charge/discharge voltage and current protection limits. Another option I am looking at is the new "100 Balance" BMS units. The look like Day, only blue instead of red, and I have heard they are made at the same factory. They claim to use active balancing similar to the JK BMS. They are priced between the basic Daly and the JK family for similar ratings.
If you do decide to go to 48 volts later, you may want to check now if the BMS you choose will support it. Some BMS units can't ever tolerate a shut down event when wired in series with another BMS. This happens because the voltage across the MOSFETs will be near double if it has to shut down. If you find a smart programmable BMS that can run from 7 or less cells up to 14 or 16 cells, then you can just wire up the common BMS across all of the cells. 14S for Li NMC EV cells, or 16S for LFP cells to make 48 volts.
Just to be sure, what is the height of your C-Max battery module? If you see 5 amps shown on the cells, it sounds like the 1.4 KWH Hybrid battery pack. I drive a C-Max Hybrid. Those cells are small, but can crank out crazy current. The 24 amp Energi cells are not much bigger, but they pack in 24 amp hours. The maximum current is actually close. The hybrid also has a few less cells. I think it is just 76S instead of 84S.
srikobatteries.com
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