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Why 8 times 280Ah 48V batteries instead of just one 2240Ah 48V battery?Went through all the information and yt videos and decided to place the order for 9 Chargery bms systems, wanted to have an extra on hand. After reading over them all Batrium still seems super nice but the chargery is much less overall and seems very easy to work with.
I had looked at that but many responded that 16s by 8 would be easier to manage and monitor.Why 8 times 280Ah 48V batteries instead of just one 2240Ah 48V battery?
For me it seem a lot easier to connect 8 cells in parallel to create one big 2240Ah cell and connect those in 16S battery.
After you need a cheap, but super nice, Zeva 16S bms and a large 500A contactor. That it, no?
And now you got a fail on one cell..you got no spare...what do you do...you dismantle all pack..? In the 8p16s you just disconnect one pack (the one With the faulty cell) and you got time to fix the problem, you can disconnect a pack to top balance it if needed...it's flexible.Why 8 times 280Ah 48V batteries instead of just one 2240Ah 48V battery?
For me it seem a lot easier to connect 8 cells in parallel to create one big 2240Ah cell and connect those in 16S battery.
After you need a cheap, but super nice, Zeva 16S bms and a large 500A contactor. That it, no?
Simple. You identify the faulty 2240Ah cell, after you identify and remove the single 280Ah faulty cells and continue to operate your 48v 1960Ah battery for the time you shout your cell supplier to had sold you crappy cellAnd now you got a fail on one cell..you got no spare...what do you do...you dismantle all pack..?
Simple. You identify the faulty 2240Ah cell, after you identify and remove the single 280Ah faulty cells and continue to operate your 48v 1960Ah battery for the time you shout your cell supplier to had sold you crappy cell
After you add a new 280Ah cell and you will be able to operate your 48v 2240Ah battery.
In my case, I have more confident in cells than in electronic BMS. So, to me, less fairly reliable BMS and more ultra reliable busbar is the way to go.
We take care of Intellectually disable people that do not have family or homes, and they do not understand many of the normal energy saving ideas. And by law we have to leave if we loose power for more than a day to a hotel which is extremely tiring, so we are taking steps to keep the power on and save on monthly costs. I need to take a few pictures just removed the ballasts and floruenscents from all the lights and put in led in the basement and kichetchen, laundry areas. Probably will not add to much but everything will help.Wow...1800kwh a month...? That's what I use in a year...?
But 400wh a month, a 20% decrease is already quite nice..!
Yes, but with multiple packs, you have to consider the not negligible fact that you will have to balance the batteries before put them back parallel (all batteries at similar voltage, if no there will have big current flow).So you need to cut all charge/discharge twice, it's rather inconvenient. If you have multiple packs you can repair the faulty one while continuing to use the remaining ones
If I have to do a single large (100 kWh and +) battery like that with only 16 large cells (2240Ah) I think it's would not be a crazy idea to have two identical BMS with the master driving the show and the second bms simply waiting to replace the master in case of fail.Then you would want the redundancy of multiple packs. With one big pack if your only BMS fails then the whole system is down. Having no SPoF plays a big role in having a high availability.
Yes, but with multiple packs, you have to consider the not negligible fact that you will have to balance the batteries before put them back parallel (all batteries at similar voltage, if no there will have big current flow).
Also, this imply more contactors (or at least kill switchs), more lugs, crimps, wires... so more chance of trouble.
Flexibility have a cost and it's often at the cost of reliability.
but never from 8 battery+8 bms.
If I have to do a single large (100 kWh and +) battery like that with only 16 large cells (2240Ah) I think it's would not be a crazy idea to have two identical BMS with the master driving the show and the second bms simply waiting to replace the master in case of fail.
Still it's easier to build, manage and monitor fewer components, contacts and crimps.Actually if each independent pack has the same complexity as the one pack solution (let's say cells + BMS + fuse + disconnect for example) the end result will be more reliable, even if the total number of parts is higher.
Well, the important here is we had explain some reasons to choose how to connect large group of cells with some advantage and disadvantage.
Now kromc5, or others reader, can choose their preferred battery configuration based on those reasons.
Timers on corridors lights, on tv set and all those things, forcing them to get up and "add" some more time to this device that will finally shutdown automatically..? Well, first analysing where the energy is going then actions should be easier.We take care of Intellectually disable people that do not have family or homes, and they do not understand many of the normal energy saving ideas. And by law we have to leave if we loose power for more than a day to a hotel which is extremely tiring, so we are taking steps to keep the power on and save on monthly costs. I need to take a few pictures just removed the ballasts and floruenscents from all the lights and put in led in the basement and kichetchen, laundry areas. Probably will not add to much but everything will help.
Perhaps I'm wrong, but I would say that as soon as your repaired pack is topbalanced, you could put it in parallel, just program the bms for a low discharge rate like 10A.. and the pack should go down to those others pack.Yes, but with multiple packs, you have to consider the not negligible fact that you will have to balance the batteries before put them back parallel (all batteries at similar voltage, if no there will have big current flow).
Also, this imply more contactors (or at least kill switchs), more lugs, crimps, wires... so more chance of trouble.
Flexibility have a cost and it's often at the cost of reliability.
I'm a big fan of keep it simple stupid solutions with no extra components, but I understand some people can prefer flexibility... but never from 8 battery+8 bms.
If I have to do a single large (100 kWh and +) battery like that with only 16 large cells (2240Ah) I think it's would not be a crazy idea to have two identical BMS with the master driving the show and the second bms simply waiting to replace the master in case of fail.
Allow me to clarify what I am trying to point out.
We use our batteries to “supply” us with power. As an example let’s use a 48v battery, 16 cells at 3v each.
At 100 amps that “supplies” 4800 watts.
Each individual cell supplies 300 watts.
So each cell is responsible for 1/16 th of the power supplied.