Battery build question using 16s battery pack

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hacksics

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Hello all,

I'm new to this forum and recently I got 16s EV battery module from used EV battery pack. The cell arrangement is 16s / 26Ah battery. I have following questions and your expert help much appreciated.

1. I'm hoping to use Daly 16s BMS for the module ref: https://www.aliexpress.com/item/32881579216.html?spm=a2g0o.store_pc_allProduct.8148356.5.cdd17b913E0GR3 . Will 60v/60A should be enough -- 3600w peak power?
2. Also I have 3 modules and was thinking an effective way to use all the packs. Can I install BMSs in each of the three modules and connect battery modules in parallel? Will the BMSs work without any issue and effectively give 78Ah (26Ah x 3) capacity ? I've contacted Daly and they said they do not recommend connecting BMSs in parallel. What does that mean?
3. What should be the inverter/hybrid inverter I choose for this? My confusion is most inverters are either 12v or 24v or 48v. Why 60v inverters are not common? Can I use 48v inverter with my 60v battery module? Is there any other disadvantage than not using the full capacity of the battery? Can you recommend few good inverters for 16s battery pack?

thanks
Sam.
 
1)Install one bms parallel the three modules at the cell level. Parallel at the cell level. Get a Bms at least twice the planned draw so 120A
if you are pulling 3600 watts and 1 bms shuts off then the other two would have to handle 60 amp being 26A bms's they both would shut down. cascading problems unless the BMS's each can handle at least 60A you might be able to get away with having three BMS's.
2) see above
3) means not to have separate BMS's for each module see above
3) because most inverters are geared towards the Lead acid 12v 24v and 48v. look at victron, outback, midnite, higher end inverters for 60v compatible inverters
The BMS is not the place to cut costs.
Later floyd
 
Thanks Floyd for the quick reply. I though about using single BMS and use 16s 3p setup. But the issue is that 16 cells in each battery module are soldered together and I have no way of removing it and creating 16s 3p setup. Any thoughts?

I will look in to Victron option. Thanks for this
 
Connect each cell balance lead 1-1-1, 2-2-2, 3-3-3 on up to 16 then connect the modules in parallel. Double and triple check each cell's voltage matches the other cells voltage before you connect the wires together.
The Victron is considered one of the best if not the best inverter around. Just be warned that victron is tailored to the lead acid battery, the terms used reflect this. The other inverters I mentioned are good too. Get one approved for use where you are. Also Sized for your usage plus 25-50% just in case. If you use heavy inductive loads a low frequency inverter/ auto transformer is called for. Make sure the inverter is pure sine wave. I have an offgrid 6kW Growatt low frequency inverter. Not one of the best but if I ever get it connected it will work fine
Later floyd
 
Thanks Floyd. What is the gauge of the wires should I use for 1-1-1, 2-2-2, etc.. ? I assume 18~22 AWG would just work fine? or should I use thick wires allowing parallel connected cells to balance in case?

I did some research and almost all hybrid inverters I can find my area are rated for 48v or less than that (24, or 12v). With 48v I can still use the 60v battery pack but it will not be charged to 100%. Am I correct?

Again thank you for helping out. I'm new to this and so excited.

Thanks!
 
Most inverters are rated at nominal voltage 48v would be 14s 51.8v voltage range that is used often is 3.4v-4.1v (47.6-57.4v)
your 16s nominal voltage 59.2v if you used the same voltage range 54.4-65.6v. in order for you to get to 60v your high voltage per cell would be 3.75v and much of the energy is above that voltage. but yes you could limit the voltage you would be losing a big chunk of power.
Keep looking and checking specs on inverters SMA sunny islands go to 63v, look at growatt and mppsolar
Someone else will chime in who knows more about the various inverters.
later floyd
ps yes 18 AWG would be fine even 22 can handle blancing on most BMS's
 
I use GTIL2 inverters. My battery is 16s Li-ion Chevy volt. I use 6 of the 60v batteries wired in parallel. They are grid tie limiting inverters that can use batteries. They have a 1kw and 2kw inverter that can use a battery from 45-90v. My max battery voltage is 64v. Could charge it higher but I’m close to 4.1v per cell at 64v. I use one 100amp Chargery bms. My array is 5660w but I only charge with 4000w and inverters use max of 3100w. I attached a bms sense wire to each cell on each battery. then each number cell-bms wire is wired to the same cell Number on the other battery. So 6 batteries means there’s 96 wires from each cell and 6 grounds one for each battery. after combining them there’s 16 wires (one for each cell number) and 1 ground which I attach to the bms cell wiring harness.
Only problem with using one bms is if one cell sense wire is disconnected then the bms won’t know about it which could cause issues. If wires are soldered then that shouldn’t happen. If one cell goes to zero volts the the bms won’t see that either but before the cell gets to zero volts the bms will alarm-disconnect the battery

There is other inverters that can use a 16s Li-ion battery voltage. Outback 68v, solark can almost at 63v, victron 66v, Reliable brand inverters can be made for whichever battery voltage you want, MagnaSine I think is 65v
 
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Thank you guys.

Grid tile inverters work but I'm actually looking for hybrid solution (grid power + battery as backup). I want inverter to function as UPS in that case. I was looking at EASUN products where they have 5kw hybrid inverters that can be connected grid, solar and battery. It also has a battery charger in-built. However most of these type only have 48v battery packs. But this one says it has overcharge protection on 65V. I'm wondering if it can go up to 65v.

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